球探网手机app

 球探网手机app关于本刊影响因子及获奖投稿须知订阅及广告专辑与专题学术会议绿色发表通道优秀论文 
   
Other Issues:  
Volume 40,Issue 10
  • Ecosystem services optional capacity value: A new indicator for valuation of ecosystem services
  • Authors:YANG Haile, WEI Qiwei, CHEN Jiakuan
  • Abstract:The valuation of ecosystem services (ESs) is helpful for effective ES management and scientific payment for ecosystem services (PES). However, there are many limitations to traditional ES valuation approaches, including the theoretical challenges and the practical difficulties. These limitations cause many difficulties in the practice of ES management and PES. To circumvent these limitations, we proposed a new indicator for the valuation ES, which we termed the ES optional capacity value (OCV). The OCV was based on two axioms: (1) human life would end if we lose any essential ES for human survival (such as oxygen or freshwater); and (2) ecosystems cannot provide any benefits to people without human activities. OCV indicates the optional capacity of supporting the total value produced by a human's economic and social activities (TVPH) provided by the total volume of an ES that was indispensable to human survival. OCV was described by the product of TVPH and the selective degree of freedom. The selective degree of freedom was evaluated by the average uncertainty of selecting the ES consumption from the total ES volume. Then, we demonstrated the new insights into OCV to assist in the understanding and quantification of ES, based on a simple case study that valued the OCV of water provision in Zhujiang River Basin (Pearl River Basin), China. The results showed that OCV could directly reflect the relationship among the total volume of an ES, the consumption volume of an ES, and the TVPH. OCV provided a new insight for understanding and measuring the value of ES. In particular, the OCV provided a clear insight into understanding and measuring the value of ES subsidies between regions. It has potential to form a significant framework for valuing ES as a complementary approach to traditional ES valuation.
  • DownLoad:Ecosystem services optional capacity value: A new indicator for valuation of ecosystem services.PDF
  • A review of freezing-thawing cycle effects on key processes of soil nitrogen cycling and the underlying mechanisms
  • Authors:XU Huan, WANG Fangfang, LI Ting, WU Xing
  • Abstract:Freeze-thawing cycle, the repeated freezing-thawing process at surface and a certain depth below soil due to seasonal or diurnal changes in heat, is a widespread natural phenomenon in the soil of middle to high latitude and high altitude. In the context of global warming, the extension and frequency of soil freezing-thawing cycle may be enhanced in some regions due to the increased occurrence of discontinuous snow cover and rain-on-snow events. These changes in freezing-thawing cycle may strongly affect soil physical and chemical properties, as well as soil microbial biomass, microbial composition and structure, which in turn would have profound impacts on the key processes of soil nitrogen (N) cycling. At present, available results of the effects of freezing-thawing cycle on the key processes of soil N cycling remain inconsistent. The underlying mechanism is still not clear and the research methods need to be further explored and innovated. Moreover, a comprehensive understanding of the key processes of soil N cycling in response to different patterns of freezing-thawing cycle is not available. Therefore, on the basis of extensive review of the existing research results, this paper summarized the research progresses and underlying mechanisms of the effects of freezing-thawing cycle on key processes of soil N cycling, including mineralization, immobilization, nitrification and denitrification, N leaching and gaseous loss. Additionally, some deficiencies in current research were pointed out. The possible key topics in the future study were also suggested.
  • DownLoad:A review of freezing-thawing cycle effects on key processes of soil nitrogen cycling and the underlying mechanisms.PDF
  • Soil biota and sustainable agriculture: A review
  • Authors:ZHANG Weixin, SHEN Zhifeng, SHAO Yuanhu, SHI Leilei, LIU Shengjie, SHI Nannan, FU Shenglei
  • Abstract:The sustainable development of agriculture is one of the key bases of continuous prosperity of human civilization. During the progress from primitive farming to industrial agriculture, the influences of "natural force" decreased but those of "anthropogenic regulation force" increased. The oncoming sustainable agriculture aims to integrate the two forces to establish a modern farming system which is expected being characterized by both close-to-nature and high efficiency. However, the conventional reductionism approach fails to fully explore the natural processes in belowground ecosystems due to their extremely high biodiversity, complex biotic and/or abiotic interactions, and great spatial and temporal heterogeneity. Consequently, it is difficult to develop a precision agricultural management to regulate a specific process successfully. Nevertheless, the critical contributions of soil biota to ecosystem services have now been universally recognized. It is an important cutting-edge research field of modern agriculture to fully improve the positive influences of soil biota on sustainable agriculture. In this study, we outlined the history and state-of-the-art in studies of soil biota and sustainable agriculture, summarized the impacts of agricultural management practices on the characteristics of soil biota and soil food webs. We emphasized the critical roles of soil biota community in sustainable farms for improving soil structure and soil fertility and reducing applications of chemical fertilizers and biocides. Finally, the research challenges and prospective research fields as well as the framework of improving the performance of soil biota in the modern farming systems were discussed. We considered that the key aspects in sustainable agriculture studies are soil organic matter, soil structure and soil food web, as well as the inherent connections among them. While the management of soil organic matter is the base and key point in regulating soil structure, soil food web and ecosystem productivity, however, it is also one of the most important uncertainty sources in sustainable farming. The systematical investigation of soil food web characteristics and their ecological functioning in representative agricultural ecosystems, based on application of holistic approaches such as isotope tracing, are needed. Thereby, the key connections among agricultural mode, soil food web characteristic and ecosystem productivity could be explored, and thus, the potential contributions of soil biota to sustainable agriculture could be fully stimulated.
  • DownLoad:Soil biota and sustainable agriculture: A review.PDF
  • A review on river ecosystem health research
  • Authors:
  • Abstract:The river ecosystem provides significant ecosystem services which are the bases of watershed sustainable manangement. Rivers are the natural ecosystems that humans and other living things depend on for survival. Throughout the history of human civilization, river ecosystems have played an important role in the origin and development of human society. Therefore, river ecosystems and human systems are integrated and interacted. By reviewing the current studies, we concluded that the definition of river ecosystem health was determined by the river itself, human demands, and management targets. The influencing factors of river ecosystem health included anthropogenic activities, land use, river habitat, water quality, water quantity, and climate change. Based on these factors, several assessment methods have been developed, including indicative species, integrated index, and mathematical model. Last, we conclued the main issues needing further research, such as the understanding of concept, assessment criteria, and land-water coupling. We must realize that healthy river ecosystems can not completely eliminate the intervence of human activities, which is not a zero-sum game. Therefore, we need to pay attention to the river health to guide river basin managers and protect river ecosystems. The further research should be enhanced by judging the river ecosystem health from a comprehensive view. The health of river ecosystem needs a healthy watershed. As an ecological corridor, river habitat should be investigeated by combining the local and regional influencing factors. The trans-regional comparsion of rive ecosystem health should be developed by a coherent criterion from the water sampling, data analysis, and result assessment. In addition, new data sources can bring benefits for the assessment of river ecosystem healthy, including remote sensing data, spatial data, and other big data.
  • DownLoad:A review on river ecosystem health research.PDF
  • A comparative review of research highlights on ecosystem services of China and USA in the latest 30 years
  • Authors:
  • Abstract:Research on ecosystem services has become one of the hotspots and key issues of ecology, geography and environmental science. Based on SCI-E and CNKI databases, this paper comparative reviewed the research status and hotspots of ecosystem services in China and USA via bibliometric method and text meta-analysis. The results show that: (1) the papers on ecosystem services in China and USA in the latest 30 years was 9327 and 9468, respectively, both increased with a significant growth trend. (2) As to the average quoting frequency per paper and total quoting in both China and USA, Research Center for Eco-environmental Sciences of Chinese Academy of Sciences and Stanford University ranked first in China and USA, respectively. The most published journal in the USA on ecosystem services was Ecological Economics, but the highest quoting journal was PNAS. Acta Ecologica Sinica was the Chinese journal with the most articles on ecosystem service and the highest quoting rate. The most influential scholars in USA are Kremen C and Polasky S, while in China are Ouyang Zhiyun and Fu Bojie. (3) There are different research hotspots of ecosystem service in China and USA in the different periods. As the two major research countries on ecosystem services themes, USA was relatively ahead of China in terms of theoretical research and methods. (4) American researchers focus more on theoretical research and models building, while the Chinese researchers focus more on the basic research and its application. Recently, the researchers in the two countries have paid more and more attention to global issues such as human well-being and ecological security. Ecosystem services, human well-being and scientific decision-making have become new hotspots. In the context of global sustainable development, the two countries have good prospects for communication and cooperation in ecosystem services research.
  • DownLoad:A comparative review of research highlights on ecosystem services of China and USA in the latest 30 years.PDF
  • Gross Ecosystem Product accounting for ecological benefits assessment: A case study of Qinghai Province
  • Authors:SONG Changsu, OUYANG Zhiyun
  • Abstract:Conducting ecological benefit assessment is of great significance for promoting ecological benefits to be included in economic and social evaluation system and pushing the construction of ecological civilization. Ecological benefits refer to the beneficial effects of natural ecosystems on human production, living conditions and environmental conditions. Gross Ecosystem Product (GEP) is a measure of the aggregate monetary value of ecosystem goods and services in a given region in an accounting period, which can reflect the ecological benefits of specific area. This research proposed the framework of GEP accounting for ecological benefits assessment, established the accounting indicator system and methods. On the basis of remote sensing data and statistical data, this research took Qinghai Province as a case to measure the GEP for ecological benefits assessment, and analyzed the stakeholders. The research results show that the GEP of Qinghai Province in 2015 was 46.42 billion Yuan, and increased by 32.6% since 2000. More than 80% of these benefits accrue regionally to other provinces out of Qinghai Province. GEP can provide visibility and give prominence to the values of nature and their contributions to human well-being with available data and methods, as well as contribute to ecological benefits assessment, which can be used as an important supplement of GDP in assessment of policy effects and ecological protection effectiveness, also serve as the reference for the establishment of market-oriented and diversified ecological compensation mechanism and the transformation from "lucid waters and lush mountains" to "golden and silver mountains", providing important information for decision makers.
  • DownLoad:Gross Ecosystem Product accounting for ecological benefits assessment: A case study of Qinghai Province.PDF
  • Quantifying the payments for ecosystem services and the value of natural resources based on the indicator of optional capacity value: a case study on water resources supply in Zhujiang River Basin, China
  • Authors:YANG Haile, WEI Qiwei, CHEN Jiakuan
  • Abstract:The ecosystem services (ES) optional capacity value (OCV) indicates the optional capacity of supporting the total value produced by human being's economic and social activities (TVPH) provided by the total volume of an ES which is indispensable to human survival. The OCV is described by the product of multiplying the TVPH by the optional capacity. The optional capacity is defined by the freedom of choosing the ES consumption from total ES volume, which is indicated by the average uncertainty of choosing the ES consumption from its total volume. The average uncertainty is described by log base 2, which indicates the uncertainty in a binary decision and is measured in bits. As combining the socio-economic index (i.e. TVPH) and the ES indexes (i.e. total ES volume and ES consumption), the OCV indicates the socio-economic conditions and the ES conditions at the same time. As the OCV describes the complementarity of development and protection, the usage of OCV in ES management will promote the endeavor for ecological civilization. However, how to introduce the OCV into management practice is still unclear. Especially, the method of how to introduce OCV into the frameworks and methods of quantifying the payments for ecosystem services (PES) and the value of natural resources (VNR) is needed to study urgently. To explore the frameworks and methods of quantifying the PES and the VNR based on the indicator of OCV, we analyzed the OCV of water resources supply in Zhujiang River Basin, China. Then, the PES between hydrologic units was discussed based on the OCV of ES spatial subsidies. The value of water resources in each hydrologic unit was quantified using the OCV of water resources supply. The results showed that the OCV of water resources supply of the hydrologic unit was supplied mostly (nearly 74%) by the subsidies from upstream hydrologic units. The value of water resources in each hydrologic unit (except the Zhujiang Delta) was more or less affected by the socio-economic conditions in downstream hydrologic units. We discussed the framework of the PES along with the principles of (1) interests sharing and responsibilities bearing, and (2) equal pay for equal work and based on the OCV of water resources supply of passing-by water. We also discussed the framework of water resources value quantification based on the OCV of water resources supply in our case study. It is obvious that these two frameworks based on the OCV will coordinate the development between hydrologic units and promote the watershed ecological civilization of Zhujiang River Basin.
  • DownLoad:Quantifying the payments for ecosystem services and the value of natural resources based on the indicator of optional capacity value: a case study on water resources supply in Zhujiang River Basin, China.PDF
  • Ecological asset accounting in North District of Tanggula Mountain
  • Authors:ZHANG Liyun, GUO Keji, LI Bingzhang, Lü Yonglei, ZHANG Lu, OUYANG Zhiyun
  • Abstract:The ecosystem accounting can offer quantitative evidence for evidence-based decision making in ecological civilization building, including ecological asset accounting and ecosystem services accounting. However, the ecological asset accounting system has not reached a consensus by stakeholders. Ecological asset indicates the ecosystems that provide ecological goods and services. In our study, we took the north district of Tanggula Mountain (Tangbei District for short) as a case to do a comprehensive ecological asset accounting. The biophysical account and changes sheet, profit and loss account sheet were built. We established a composite index of ecological asset. The results revealed that the grassland ecosystems were mainly of good level (68.46%). The wetland ecosystems were mainly of excellent level (59.72%). There were 138 kinds of wild fauna and flora, of which ten were state-level key protected animals. The composite index of ecological asset was 79.77 in 2015 that decreased by 3.60% from 2000 to 2015. During the fifteen years, the ecological assets of wetland ecosystem and grassland ecosystem increased by 164.23 km2 and 2.82 km2, respectively. The wetland asset increased by 202.90 km2 mainly because of wetlands recovery (200.50 km2) and decreased by 38.63 km2 mainly due to wetland degradation (36.23 km2). The grassland ecosystem asset increased by 39.18 km2 that mainly caused by grassland expansion and decreased by 36.26 km2 that mainly caused by wetlands recovery (26.20 km2) and desertification (9.65 km2). The comprehensively accounting system of ecological asset meant a lot to implement outgoing accountability regime so as to build ecological civilization in China.
  • DownLoad:Ecological asset accounting in North District of Tanggula Mountain.PDF
  • Application of the gross ecosystem product accounting theory on rural ecological civilization assessment in Hainan Province: A case study of Wenmen Village in Sanya
  • Authors:GENG Jing, REN Bingnan
  • Abstract:Construction of rural ecological civilization is one of the major projects in the ecological conservation of Hainan Province. By cultivating "Civilization Eco-Villages" and creating "Beautiful Villages", the ecological civilization in Hainan Province has gradually advanced in depth, and it has ushered in a rare opportunity for development in the rural areas. The gross ecosystem product (GEP) accounting can play the role of evaluating the performance of ecological civilization through calculating the values of ecosystem products and services, and eventually supply the scientific data to decision makers for finding the balance between ecological protection and rural economic development in the future. At the same time, it can be used to reveal the current resource values of the village that will help to attract more capital, technology, talents and other to the rural area, and make lucid waters and lush mountains invaluable assets. In this paper, GEP of Wenmen Village, Tianya District, Sanya City, Hainan Province was accounted as a case study. The results showed that the GEP of Wenmen Village in 2007 was 10297.79×104 yuan and the value per unit area was 5.06×104 yuan/hm2. The value of ecosystem products accounted for 24.93% and the value of ecosystem regulation services accounted for 75.07%. Among the value of services, the values of water conservation, flooding mitigation, C fixation, oxygen production, and air purification were 3287.44×104 yuan, 1593.32×104 yuan, 2815.31×104 yuan, and 34.72×104 yuan, respectively. The forest land contributed the most to the value of ecological regulation services, accounting for 69.57% of the total value, followed by the farmland (14.86%) and orchard land (11.66%). The study suggests that, with the future strengthening of rural ecological civilization construction, including the improvement of nature resource management system, and the integration of ecological agriculture and rural tourism, it is necessary to improve the content of accounting.
  • DownLoad:Application of the gross ecosystem product accounting theory on rural ecological civilization assessment in Hainan Province: A case study of Wenmen Village in Sanya.PDF
  • Ecological compensation for cross-boundary pollution control of livestock and poultry: a case study of Jiuzhou River Basin in national ecological compensation demonstration area
  • Authors:ZHAO Suqin, SUN Xiang, HOU Donglin, ZHU Yi
  • Abstract:Research on ecological compensation standard is a challenging topic in the field of river basin management. We estimated the cross-boundary pollution caused by pig breeding in Jiuzhou River Basin as a case study, and calculated the total amount of pollutant reduction based on pollutants control targets of COD, TP, and TN. In the estimation process, we set up three typical control scenarios, which included: closing pig farms in forbidden breeding areas, transforming bed breeding mode, and central treating of wastewater. Considering the pollutant reduction target as the principal constraint, a linear programming model was conducted to calculate the input cost of water pollution control under different treatment scenarios; we also modelled the minimum ecological compensation based on these scenarios. Taking the water consumption, water supply and GDP as the main constraints, we established a compensation analysis with the certain proportion of investment from central government, local government of Guangdong and Guangxi province; therefore, the ecological compensation amount of each side was determined based on their investment. In this research, Monte Carlo simulation and sensitivity analysis was applied to estimate the uncertainty of parameters while modelling compensation. All possible values and variance contribution rates to ecological compensation under uncertain model parameters were calculated, these parameters included breeding volumetric ratio (k1), wastewater discharge to river basin in forbidden zone (k2), and daily wastewater discharge amount with loft-bed (k3) and daily wastewater discharge amount under traditional breeding case (k4). Our results show that: (1) the reduction amount of total pollutants for COD was 378752.98 t, 2161.60 t for TP reduction and 13951.70 t for TN reduction under 90% guarantee rate of water quality standard; (2) total amount of ecological compensation was 1.503 billion based on the cost accounting method, and the allocation amount of the central government, local government of Guangxi and Guangdong province was 376 million, 331 million and 796 million, respectively; (3) under the confidence intervals level of 95%, the ecological compensation values in two different scenarios were calculated as 1.25-1.74 billion and 0.93-2.19billion. (4)refering to the sensitive analysis of parameters, the variance contribution rates of parameters k1, k2 and k3 was 79.50%, 18.90% and 1.60%, separately in scenario 1, and 88.80% of parameter k2 and 11.20% for 44 in scenario 2.
  • DownLoad:Ecological compensation for cross-boundary pollution control of livestock and poultry: a case study of Jiuzhou River Basin in national ecological compensation demonstration area.PDF
  • Spatio-temporal differentiation of interaction of ecosystem services and regional responses in the “Belt and Road” area
  • Authors:XU Jianying, CHEN Jixing, LIU Yanxu, FAN Feifei, WEI Jianying
  • Abstract:Most developing countries in the "Belt and Road" region are located in the ecological fragile areas, and the spatial allocation of land resources needs to be optimized urgently. The study on interactions between ecosystem services can provide quantitative support for land use decision, but the expression of this interactions varies greatly in different regions. This study based on InVEST model estimated the value of four ecosystem services from 2000 to 2015, including soil retention, water yield, carton storage, and habitat quality. The spatio-temporal differentiation of ecosystem services were also analyzed. In addition, we quantitatively assessed the spatial patters of interactions among different ecosystem services by applying the correlational analysis method and spatial autocorrelation. The results showed that the spatial pattern of soil retention, water yield, carbon storage, and habitat quality in the central and western Asia was all the low value region, while the distribution of the high value region was inconsistent. There was a significant synergistic relationship between the services, but the regional heterogeneity of the cold hot spot pattern was significant. There was a trade-off between the ecosystem services of taiga forest, temperate steppe and shrub in the ecozonal unit. In a country unit, there were synergies and trade-offs between ecosystem services. The synergistic relationship between water yield and carbon fixation has a good response to population distribution, while the response of soil conservation and carbon fixation to population distribution is not obvious. The quantitative assessment of ecosystem services and trade-offs provides a basis for optimal allocation of regional land resources. The results can provide spatial guidance to the international cooperation for ecological protection in the "Belt and Road" region.
  • DownLoad:Spatio-temporal differentiation of interaction of ecosystem services and regional responses in the “Belt and Road” area.PDF
  • Characteristics of coordination changes and spatial coupling relationship between urbanization and ecosystem services
  • Authors:ZHANG Jiatian, JIAO Wenxian, HAN Baolong
  • Abstract:The study of the coupling and coordination relationship between urbanization and ecosystem services as a bridge connecting the natural environment with the social economy has received widespread attention. Selecting 333 cities in China, we calculated the urbanization level and ecosystem service capacity with the integrated evaluation index in 2010 and 2015. At the same time, the temporal and spatial evolution characteristics of the urbanization level and ecosystem service capacity were analyzed, and the spatial econometric model was used to explore the relationship between ecosystem services and urbanization. The study found that: (1) the urbanization level of the cities shows the spatial pattern of "East High-West Low, and South High-North Low". The average value increased from 0.0792 in 2010 to 0.0987 in 2015, which increased by 24.62%. Most cities are still in the preparation development stage, while only Shanghai and Shenzhen have entered a highly developed stage. (2) The urban ecosystem service capacity shows a "Southeast High-Northwest Low" spatial pattern, whose average value increased from 0.2542 in 2010 to 0.2621 in 2015, with an increasing of 3.11%. But the average value of 81 cities dropped from 0.1201 in 2010 to 0.1183 in 2015, with a decreasing of 1.50%, which have formed a spatial aggregation feature of the significant deterioration. (3) By the Spatial Error Model, the regression coefficients of the score of integrated urbanization, population urbanization, land urbanization, and economic urbanization are -0.1303, -0.2019, -0.2404, and 0.1946, respectively. Economic development has become a powerful tool for improving ecosystem services. Finally, we suggest that the coordinated management of ecological space should be strengthened; the inter-regional economic cooperation development mechanism needs to be established; and the population growth, land construction, and economic development should be coordinated.
  • DownLoad:Characteristics of coordination changes and spatial coupling relationship between urbanization and ecosystem services.PDF
  • Changes in landscape pattern of built-up land and its driving factors during urban sprawl
  • Authors:CHE Tong, LI Cheng, LUO Yunjian
  • Abstract:Understanding changes in the landscape pattern of built-up land its driving factors not only helps to solve the eco-environmental problems in cities but also provides a scientific basis for urban land use optimization and landscape planning. In this study, we used multi-source data (e.g., 30 m resolution Landsat images and statistical yearbooks) to analyze changes in sprawl mode, morphology and landscape pattern of built-up land in a rapidly urbanized medium-sized city-Yangzhou City, Jiangsu Province, China. Furthermore, we employed the boosted regression tree method to quantify the effects of geographic and socioeconomic factors on landscape patterns of the built-up land, which revealed changes in the driving factors with the built-up land sprawl. The results showed that the area of the built-up land gradually increased from 1995 to 2015. All of the three sprawl modes (infilling, edge-expansion and leapfrog) appeared in each period, but their relative dominances varied with the built-up land sprawl. The morphology of the built-up land underwent an alternating process of "diffusion" and "coalescence", while the landscape pattern tended to homogenize (i.e., decreased fragmentation and increased aggregation of the built-up landscape). Geographical factors (altitude and distance from the geographical center of a county) played more important roles in shaping landscape pattern than socioeconomic factors. Moreover, the combined effects of geographical factors decreased with the built-up land sprawl, while socioeconomic effects became more significant. Landscape fragmentation of the built-up land increased with increasing altitude and population density and decreasing total population; meanwhile, the landscape aggregation was inhibited. However, effects of other factors (i.e., distance from the center of a county, GDP per capita, and the proportion of secondary industry) on landscape pattern varied with the built-up land sprawl. For example, the promoting effect of GDP per capita on landscape fragmentation turned to an inhibiting effect, while the inhibiting effect of secondary industry turned to a promoting one.
  • DownLoad:Changes in landscape pattern of built-up land and its driving factors during urban sprawl.PDF
  • Assessing landscape ecological risk based on landscape pattern and services in Guangzhou during 1990-2015
  • Authors:LIU Zhenhuan, ZHANG Guojie, FU Fengjie
  • Abstract:Landscape ecological risk assessment (LERA) is an effective tool developed in recent years to support landscape ecological construction and management. The ecological risk caused by landscape change or land-use and land-cover change has received increased attention by policy-makers. High-intensity human activities disturbed the pattern and function of ecosystem and the hotspot of landscape change in urban areas, which contributed to the uncertainty of ecological risk. Therefore, it is urgent to improve the LERA method to provide quantitative analysis for landscape management and comprehensive risk prevention. There are several methods used for LERA such as landscape metrics and landscape source-sink risk. However, the classic model of traditional ecological risk assessment followed the mode of risk source identification-receptor analysis-exposure and hazard assessment. In order to improve the LERA method in urban areas, this research followed the landscape metrics method, but improved the algorithm of vulnerability for landscape services. A series of landscape services indicators were reselected to denote landscape vulnerability, including carbon storage, water provision and purification, soil conservation, and habitat quality. This study used multi-source data to analyze the spatio-temporal changes and characteristics of landscape ecological risk based on 1 km×1 km spatial resolution in Guangzhou, a typical area experiencing rapid urbanization, for the period 1990-2015. The results were as follows: (1) LERA based on landscape pattern and landscape service can effectively evaluate the spatial distribution of urban landscape ecological risk. The low landscape ecological risk type is typical and these areas were regularly distributed over the 25 years. In the study stage, the year of 2000 was the transition period. (2) The landscape disturbance degree of Guangzhou increased first and then decreased over the 1990-2015 period; 2000 was the year when the degree of landscape disturbance changed. Landscape vulnerability is increasing. Together, medium vulnerability and high vulnerability areas accounted for more than 60% of the area; these areas were more common in the south than the north, and more common in the west than in the east. The landscape ecological risk in Guangzhou was increasing before 2000, and showed a tendency to decrease after 2000. (3)The landscape ecological risks transition showed that landscape changes and ecological risk have a good spatial consistency in Guangzhou during the 25-year study period. The area with a low landscape risk was 40.74%, and this area was mostly distributed in the northern mountainous areas. The area with a high landscape risk was 6.67%, the transition from low risk to high risk was 32.28%, and high risk change to low risk was 20.31%. This shows that landscape changes in urban area has a high risk after rapid urbanization. However, the uncertainty of LERA still plagued the application of LERA in policy-making. Further research can pay more attention to the verification of assessment results or use scenario analysis to quantify spatiotemporal characteristics of risk to improve the scientific basis for the early warning and prediction of landscape ecological risk. Then, the LERA applications in urban areas can be acceptable for landscape management or policy-making.
  • DownLoad:Assessing landscape ecological risk based on landscape pattern and services in Guangzhou during 1990-2015.PDF
  • Changes of landscape fragmentation and connectivity with urbanization: a case study of Kunming City
  • Authors:SHI Fangning, LIU Shiliang, AN Yi, SUN Yongxiu, DONG Shikui, WU Xue
  • Abstract:Urbanization can not only change the landscape types and composition, but also change the spatial morphology and decrease the natural habitat connectivity. Depicting the spatial relationship between artificial surface, arable land and natural habitat is of great significance to examine the landscape ecological effects, especially for the interaction between different landscapes and changes of structure and function. The effects of fragmentation and morphological changes on landscape connectivity with urban expansion of Kunming City, Yunnan Province in 1990-2015 were analyzed in this study by using the urban fragmentation index (UFI) to depict the level of landscape fragmentation. Based on morphological spatial pattern analysis (MSPA), seven landscape morphological elements (core, islet, bridge, loop, perforation, edge, and branch) of arable land and natural habitat were obtained. Three edge widths were selected to compare the influence of edge widths on the landscape morphology. The landscape connectivity changes were evaluated by probability of connectivity (PC) and importance value of patches (dPC). The average UFI and dPC were calculated on the grid of 4 km×4 km, and the correlation among different variables were analyzed by the three-dimensional curved surface graph. The results showed that the artificial surface in Kunming has been expanding, occupying a large amount of arable land. The annual increase rate of landscape fragmentation has been increasing in the past 25 years. The results of MSPA indicated that the arable land showed a continuous and stable declining trend, and the landscape morphology of natural habitat showed little change from 1990 to 2010. After 2010, there has been a dynamic process from stability to fluctuation and then to fragmentation. There were significant differences between different edge widths. The wider the edge width was, the more obvious the change of connectivity was. This fact indicated that urbanization had a more serious impact on small green patches. The change of dPC was consistent with that of the UFI, and the change was concentrated in the eastern region of Kunming. With the increase of the UFI, the landscape connectivity decreased year by year. The correlation analysis showed that the landscape connectivity experienced a process from fluctuation to steady decline with the increase of fragmentation. In general, the urbanization of Kunming has caused continuous reduction of arable land. Although the loss of large-scale natural habitat has not been caused by the urbanization, the connectivity has been reduced to a certain extent. It is necessary to control the spatial pattern to avoid the negative impact of the urbanization on the overall landscape connectivity.
  • DownLoad:Changes of landscape fragmentation and connectivity with urbanization: a case study of Kunming City.PDF
  • Comparative study on CO2 emissions from fossil energy consumption and its influencing factors in typical cities of China
  • Authors:ZHENG Ying, LU Fei, LIU Jingru, WANG Xiaoke
  • Abstract:Cities are the main regions of fossil energy consumption and CO2 emissions. Analysis of characteristics of the CO2 emissions from fossil energy consumption in typical cities, and clarification of the dynamics and critical influencing factors of the CO2 emissions in different cities could provide important scientific basis for CO2 mitigation action in urban areas. With the IPCC recommended methods and China-specific emission parameters, the CO2 emissions from fossil fuel combustion were estimated in 11 typical cities from 2006 to 2015. Based on the emission characters and economic development, the 11 cities are categorized into four groups, namely, cities with highly developed economy (including Beijing, Shanghai and Guangzhou), cities with high carbon emission (including Chongqing, Urumqi and Tangshan), cities with low emission and low economic growth (including Harbin, Hohhot and Daqing), and the cities with low emission but high economic growth (including Guiyang and Hefei). Then the urban CO2 emissions were decomposed by Logarithmic Mean Divisia Index (LMDI) method to compare the differences of influencing factors among the above four categories of cities. The results indicated that CO2 emissions from most cities increased during the study period, while the CO2 emissions of Beijing and Guangzhou showed a decreasing trend. The emissions from the industrial sector took the dominant position in both of the total emissions from the cities and their dynamics. The per capita CO2 emissions of different cities showed a similar variation pattern to that of the total CO2 emissions. Cities with highly developed economy had the lowest CO2 emissions intensity (avg. 0.088t CO2/k Yuan), and the values went gradually higher for cities with low emission and low economic growth (avg. 0.282t CO2/k Yuan), cities with low emission but high economic growth (avg. 0.305t CO2/k Yuan), and cities with high carbon emission (avg. 0.662t CO2/k Yuan). For all the 4 categories of cities, both economic development and population size enlargement could lead to CO2 emissions increment, but economic development made the major contribution while the effects of population size were relatively small. Meanwhile, the decrease of energy intensity effect acted as the main driving factor of CO2 emissions reduction, and this reduction effect is stronger in cities with highly developed economy or with high carbon emission than those in the rest two categories of cities. The effect of industrial structure promotion restrained CO2 emissions in 6 cities where the average annual growth rate of the tertiary industry GDP was higher than the secondary industry. The energy structure effect only inhibits the CO2 emissions of Beijing and Guangzhou (with the accumulative contribution at -21.73Mt and -0.03Mt, respectively), where coal's proportion in fossil energy consumption was low and going down fast. While in the cities with high carbon emission, the change of energy structure has the most obvious promoting effect on the CO2 emissions.
  • DownLoad:Comparative study on CO2 emissions from fossil energy consumption and its influencing factors in typical cities of China.PDF
  • “Source-sink” landscape identification of the urban heat island and the cooling efficiency
  • Authors:MA Ruiming, XIE Miaomiao, YUN Wenju
  • Abstract:In the context of rapid urbanization, the difference in cooling efficiency of different landscapes is the basis of understanding the influence mechanism underpinning landscape pattern on urban heat island effect. Existing studies on the heat island effect primarily use land use or land cover as the proxy for the source and sink landscape. This creates an information bias by ignoring the thermal characteristics of the landscape and the thermal relationship with adjacent landscapes. It is deemed necessary to explore the landscape classification method for the urban heat island effect and analyze differences in the cooling efficiency of landscapes with different characteristics. Based on "source-sink" landscape theory, this study constructs a landscape classification method for urban heat island using the western part of Shenzhen City as the study area. Sixteen urban landscape types were divided based on the extraction of surface features such as Normalized Difference Vegetation Index, Normalized Difference Moisture Index, and Impervious Surface Area and land surface temperature from Thematic Mapper remote sensing imagery in 2010. With the analysis of the temperature relationship under the equal distance gradient for landscapes with different surface features, the "source-sink" landscape of urban heat island was identified. On this basis, the composed landscape characteristics of the "source-sink" landscape were analyzed, and the cooling efficiency of landscape with area and temperature as influencing factors was calculated. Combined with the landscape pattern index, the cooling efficiency of separate areas and shapes of the sink landscape was analyzed. Five landscape types were identified as the urban heat island sink landscape. The area is approximately 533 km2, accounting for 45.5% of the total study area. Results of cooling efficiency showed that the cooling efficiency of the "sink" landscape is 1.54, among which the contribution rate of green space and shadow landscape was higher. Based on the analysis of landscape patterns, it was found that the cooling efficiency both first increases and then decreases with the increase of the index value. The results can provide support for the shape and area setting of a cooling landscape in urban planning and urban green infrastructure design decision-making, mitigate urban heat island effect and increase the cooling efficiency at the landscape level.
  • DownLoad:“Source-sink” landscape identification of the urban heat island and the cooling efficiency.PDF
  • Study on the influence of urban green space on the physical and mental welfare of residents
  • Authors:YU Jiali, YAN Lijiao, DENG Jinyang, LI Jian
  • Abstract:Green spaces in cities provide an urban landscape where human beings can live close to nature. The inclusion of green space is an important part of improving the living environment of residents and an effective way to improve their physical and mental health. Taking the main urban area of Hangzhou as the research subject, a remote sensing image of urban green space was interpreted by GIS technology to obtain the green space layout of the main urban area of the city. At the same time, the population density was used as the resistance factor, the number and area of green space within 500m network distance of traffic network as classification standard. Secondly, perceptual data from 665 residents were obtained through questionnaire surveys of 45 high, medium, and low residential areas with different grades. Finally, a structural equation model was used to evaluate the inter-group analysis based on the number of green spaces and playtime, and distinguish the differences between various groups and the causes of these differences. The model was also used to assess the number of green spaces and the area they covered, residents' cognition, motivation, and green space attraction, plus the relationship between health benefits and satisfaction. The results show that the number of urban green spaces and the number of times the residents use the spaces have a significant positive relationship with the residents' well-being. The residents' perceptions of the role of green space and their motives for visiting green space further affect their physical and mental health. Indeed, an understanding of the importance of urban green space will stimulate residents' enthusiasm for using green spaces and increase the frequency with which they visit them. In addition, individuals with different social attributes have different needs for green space; therefore, the resulting welfare effects and level of satisfaction will also vary. Finally, suggestions are made for the future development planning of urban green space from three aspects: increasing the number of street green spaces and neighborhood parks around residential areas, enhancing the attractiveness of green spaces, and raising the awareness of residents of the role of urban green space.
  • DownLoad:Study on the influence of urban green space on the physical and mental welfare of residents.PDF
  • Dynamic analysis of coastal landscape in China's East China Sea based on landform types
  • Authors:TIAN Peng, LI Jialin, YE Mengyao, SHI Xiaoli, WANG Lijia, LIU Ruiqing, WANG Zhongyi, WANG Haifeng, GAO Yang
  • Abstract:Based on the landform information data and six phases of landscape data of the East China Sea, the landform types and landscape dynamics of the continental coast of the East China Sea were studied from 1990 to 2015, and the temporal and spatial distribution of landscape patterns under various topographical types were analyzed. The results showed that: (1) the landform type of the East China Sea coast was dominated by hilly landforms, followed by small rolling hills, plain, platform and medium rolling hills. The forest land was a dominated landscape type, followed by cultivated land and construction land. (2) The change of plain, platform and hilly landforms was mainly based on the conversion of cultivated land to construction land, while the small and medium rolling hills were mainly grassland to forest land. (3) The intensity of landscape change under different geomorphological units was in order of plain > platform > hills > small rolling hills > medium rolling hills. The degree of landscape change in 2005-2015 was less than that in 1990-2005, and the intensity of landscape changes was decreasing. (4) The landform type had great influence on the fractal dimension and stability index of the landscape. The fractal dimension of the waters was the largest in the plain. The fractal dimension of the cultivated land was the largest in the platform and hills, while the dimension of the small rolling hills was the largest in the unused land. The construction land had the largest fractal dimension and the opposite stability index. The cultivated land tended to be stable in low-lying landform types. Forest land and grassland were mostly distributed in hills and mountainous areas with higher elevations. The water area and construction land had the largest fractal dimension and stronger stability in the plain.
  • DownLoad:Dynamic analysis of coastal landscape in China's East China Sea based on landform types.PDF
  • Evolution and simulation of ecosystem patterns in Guangdong-Hong Kong-Macau Bay Area
  • Authors:WANG Wenjing, HAN Baolong, ZHENG Hua, OUYANG Zhiyun
  • Abstract:Rapid urbanization has been one of the primary drivers of ecosystems change in the Guangdong-Hong Kong-Macau Bay Area (the Great Bay Area). To understand these spatio-temporal dynamics, it is important to simulate ecosystem trend and patterns during regional land use optimization, preventing and controlling the ecological risks of urbanization. Based on land use-land cover (LULC) data for the years 2000, 2005, 2010, 2015 and 2018, this paper analyzed the evolution of ecosystem types and landscape patterns in this region. A CA-Markov model was used to simulate ecosystem pattern in 2025. The results showed that: (1) the forests, farmland and urban land were the main ecosystem types in the Greater Bay Area in 2018, accounting for 53.99%, 22.67% and 14.51% of the total area, respectively. (2) From 2000 to 2018, the area of farmland, forest, and wetland decreased by 1983 km2, 740 km2 and 278 km2 respectively, and the area of urban and grassland increased by 2896 km2 and 103 km2, respectively. The growth in urban areas came from the conversion of surrounding farmland, woodland and wetland. Due to poor management, portions of woodland degraded to grassland, leading to the growth of the latter. The change rate of ecosystem types in the Greater Bay Area had obvious periodical characteristics. The fastest period of urban expansion was from 2000 to 2005, leading to a rapid decline in farmland. The rate of urban expansion and farmland reduction slowed after 2005.The speed of forest reduction accelerated in 2000-2015 and slowed down in 2015-2018. The grassland area increased from 2000 to 2015, with a slow growth rate from 2000 to 2010 and a rapid growth rate from 2010 to 2015, then decreased from 2015 to 2018. From 2000 to 2018, the wetland area continued declining with the same speed. (3) Under the effects of demographic urbanization and LULC urbanization, the landscape pattern changed significantly. Fragmentation and separation increased, and the diversity and evenness of the landscape decreased. The Contagion index (CONTAG) increased and the Division index (DIVISION) increased, indicating that the fragmentation and heterogeneity of the landscape increased. The largest patches of farmland and forestland were destroyed, and the Number of Patches index (NP) increased. Urban patches showed a spreading growth, while the urban landscape's degree of fragmentation and separation fell. (4) The ecosystem pattern in 2025 was simulated based on a CA-Markov model, and the accuracy test was carried out by comparison with the actual data in 2015; the Kappa coefficient was 0.94. Compared with 2018, the urban area is projected to increase by 609 km2, extending outward along the larger urban patches, mainly in Guangzhou, Dongguan and Foshan prefectures. The area of farmland and forest ecosystem is projected to decrease by 309 km2 and 316 km2, respectively. The areas of grassland ecosystem and wetland ecosystem are projected to remain unchanged. Based on the change and simulation of ecosystem patterns in the Greater Bay Area, it was found that the farmland protection red line, ecological protection red line and the protection of important ecological space integrity (all national policies) played important roles in reducing the ecological risk of urbanization in a rapidly urbanizing region.
  • DownLoad:Evolution and simulation of ecosystem patterns in Guangdong-Hong Kong-Macau Bay Area.PDF
  • Construction of ecological security pattern based on boundary analysis: a case study on Jiangsu Province
  • Authors:WANG Xiaoyu, CHEN Tianqian, FENG Zhe, WU Kening, LIN Qian
  • Abstract:The ecological security pattern is the basic guarantee and important way to achieve regional ecological security, which can effectively alleviate the contradiction between ecological protection and economic development. Taking Jiangsu Province as the research area, two levels of ecological sources were determined through the importance of ecological services, ecological environment sensitivity and protection level. The ecologically advantageous land-use types containing the cultivated land, forest land and water body were selected for boundary analysis respectively for correcting the resistance surface based on land-use types. The corrected resistance surface was combined with the resistance surface constructed by the spatial distribution of the population to form the comprehensive resistance surface. The ecological corridors were identified based on the minimum resistance model. Then, the provincial ecological security pattern was constructed and optimized. The results show that the primary source area of the study area is 2908.28 km2, accounting for 2.00% of the total area, and the secondary source area is 7944.92 km2, accounting for 9.60% of the total area. The total length of the ecological corridor is 2284.89 km. The areas where the corridors are interconnected, are the integration of the ecological elements. The overall distribution of the ecological security pattern is "four belts and four districts". This paper uses the boundary analysis of the land-use types to construct the resistance surface, which can provide new ideas for the ecological safety pattern construction method. The research results can provide a scientific basis for the regional ecological protection of Jiangsu Province.
  • DownLoad:Construction of ecological security pattern based on boundary analysis: a case study on Jiangsu Province.PDF
  • Effects of water and nitrogen additions on the intra- and inter-annual dynamics of plant nitrogen concentration in Inner Mongolia temperate steppe
  • Authors:GUO Qun
  • Abstract:As a key factor that affects various ecosystem processes, plant nitrogen (N) concentration is very important to forecast the responses of ecosystem to global climate change, e.g., altered precipitation regime and enhanced N deposition. Grassland, one of the most sensitive ecosystems to climate change, has been paid insufficient attentions in terms of the intra- and inter-annual dynamics of plant N concentration. In this study, a five-year manipulative field experiment was conducted by employing N addition (10 g N m-2 a-1) and water addition (80 mm a-1 in terms of five intensities, i.e., 2 mm×40 times, 5 mm×16 times, 10 mm×8 times, 20 mm×4 times, and 40 mm×2 times) in a typical steppe in Inner Mongolia temperate grassland. We analyzed the effects of water and nitrogen additions on the intra- and inter-annual dynamics of plant nitrogen concentration. We found that water addition of 10 mm×8 times and 40 mm×2 times decreased ecosystem plant N concentration in the dry years, while that of 20 mm×4 times increased ecosystem plant N concentration, but these increases or decreases were not significant statistically. Under water additions of other lower intensity (2 mm×40 times and 5 mm×16 times), neither increase nor decrease patterns were clearly observed across years. Plant N concentration of two dominant species, Stipa krylovii and Artemisia frigida, was both lower in the early and late growing season, while it was higher in the middle of the growing season. Water addition decreased plant N concentration of these two dominant species throughout the growing season, but without significance. The N addition enhanced ecosystem N concentration and plant N concentration of two dominant species across the growing season. However, this enhancement could be down regulated by water addition, and this down regulation due to water addition increased with the duration of experiments. The N and water additions both increased inter-annual variability of ecosystem N concentration, while the effects they exerted on intra-annual variability of plant N concentration of two dominant species dependent on the annual precipitation amount. Our work has important implications for model improvement and an advanced understanding of grassland-response to N deposition and the altered precipitation regime.
  • DownLoad:Effects of water and nitrogen additions on the intra- and inter-annual dynamics of plant nitrogen concentration in Inner Mongolia temperate steppe.PDF
  • Multi-scale response of runoff to vegetation and climate change in karst watersheds
  • Authors:ZHU Jingxuan, LIU Wen, LI Zhenwei, LI Xiaohan, ZHANG Zhihui, XU Xianli
  • Abstract:The influences of vegetation cover and climate change on runoff may have scale dependence. However, few studies have been carried out in the southwest karst region with vulnerably ecological environment and complex geological structure. Therefore, we selected the study area in the Xijiang watershed with four sub-watersheds (Yujiang, Hongshuihe, Xunjiang, and Wuzhou), which is characterized by typical karst landforms in southwest China. The objective of this study is to investigate the multi-scale responses of runoff to vegetation and climate change in karst watersheds. The Mann-Kendall trend test is used to analyze the trends in runoff, Normalized Difference Vegetation Index, precipitation, potential evapotranspiration, and temperature in these watersheds from 1982 to 2015. Furthermore, the correlation of runoff with vegetation and climate factors at different scales was quantified. Additionally, runoff was predicted by using the multivariate empirical mode decomposition method. The results indicated that the runoff of the Hongshuihe watershed showed a significant decreasing trend (P<0.05). The main representative scales for runoff were 3 years and 5 years in the Yujiang watershed, 10 years and 22 years in the Hongshuihe watershed, and 3 and 22 years in Xunjiang and Wuzhou watersheds. It was found that scale-dependent relationships between runoff and its influencing factors. At different scales, precipitation and potential evapotranspiration were always significantly correlated with runoff (P<0.05), while the temperature and NDVI were no significantly correlated with runoff at some scales in four watersheds. The multivariate empirical mode decomposition method (R2: 0.81-0.86) was more accurate at predicting runoff than the stepwise multiple linear regression (R2: 0.69-0.78). The study can provide the scientific basis for the rational utilization of water resources, the sustainable development of social economy, and ecological environment protection in karst watersheds.
  • DownLoad:Multi-scale response of runoff to vegetation and climate change in karst watersheds.PDF
  • Time-lay effects of climate on water use efficiency in the Loess Plateau of northern Shaanxi
  • Authors:DUAN Yifang, REN Zhiyuan, SUN Yijie
  • Abstract:Based on the primary data such as temperature, precipitation, MODIS-GPP and MODIS-ET datasets at monthly scale from 2000 to 2014, using pixel-based time-lay patial correlation analysis, the climate time-lag effect of water use efficiency (WUE) and its effective factors on the Loess Plateau of northern Shaanxi were analyzed. The results showed that under the influence of the ecological project of converting farmland to forestry or grassland and the climate change, the interannual WUE in the Loess Plateau of northern Shaanxi showed a fluctuating trend, among which, 2001-2003 decreased significantly, 2003-2005 and 2010-2013 increased significantly, and the change ranged from 1.06 to 1.67 gCmm-1m-2 from 2000 to 2014. Influenced by different vegetation types, the intraannual WUE showed three kinds of changes: rapid double peak, slow double peak and single peak. WUE in the Loess Plateau of northern Shaanxi had obvious time-lag effect on precipitation, and the lag time was mostly 3 months. But the response degree and time-lag of WUE to precipitation in I-1, I-2, II-2 and III-3 eco-functional areas were significantly lower than those in other eco-functional areas. However, the time-lag effect of WUE to temperature was weak, and the lag time of WUE to temperature was 1-2 months, which only lied in III-2 and III-3 eco-functional areas. The time-lag effect of WUE to precipitation under different vegetation types was more significant. WUE of desert vegetation had the strongest time-lag effect to precipitation, with the lag time of nearly 3 months, while the lag time was the weakest under coniferous forest, with the lag time of 2.1 months. But the time-lag effect of WUE to temperature was generally weak. The time lag of WUE to temperature under coniferous forest was 15 d, and there was no time-lag under most other vegetation types. The sensitivity of time-lay effect on climate to vegetation coverage had a threshold effect. When the vegetation coverage was higher than 62.3%, the time-lag effect to precipitation gradually weakened, and that to temperature gradually appeared.
  • DownLoad:Time-lay effects of climate on water use efficiency in the Loess Plateau of northern Shaanxi.PDF
  • Effects of simulated acid rain on soil respiration and microbial diversity in Moso bamboo forest in subtropical China
  • Authors:WANG Nan, PAN Xiaocheng, BAI Shangbin
  • Abstract:Acid rain is an important phenomena in global climate change and it can strongly influence forest ecology. Many studies have shown the impacts of acid rain on soil respiration, but the results are very different due to the different species and environmental conditions. The persistent acidification of soil caused by acid rain has an important impact on the carbon cycle of the Moso bamboo forest ecosystem. To quantify the effect of acid rain on the soil ecosystem of Moso bamboo forest in subtropical China, the experiment of soil by simulated acid rain in the field was carried out for two years of 2016-2018. Two treatments of the simulated acid rain with pH value of 4.0 (T1) and 2.0 (T2) were set, at the same time taking pH value of 5.8 (CK) as control. The relationship between soil CO2 emission and soil microbial diversity in the Moso bamboo forest of Tianmu Mountain National Nature Reserve under the simulated acid rain was analyzed, and the relationship between soil respiration, soil microbial and soil physical and chemical properties in subtropical Moso bamboo forest was determined. The results showed that soil respiration rate increased firstly and then decreased after the buffer period under the action of acid rain, and the intensity of the action was T2>T1. The sensitivity of soil respiration to temperature in different treatments from high to low was T2, CK, T1, and increased seasonally with increasing temperature. PCR-DGGE analysis showed that strong acid rain treatment inhibited the growth of soil bacterial community and the order of soil bacteria diversity and richness from high to low was CK, T1, and T2. The weak acid rain had a positive effect on the diversity and abundance of soil fungi, and the opposite was strong acid rain. The effects of acid rain resulted in the decrease or disappearance of Bacillus, Caulobacter, Cystobacteraceae, Bradyrhizobium and Candida, as well as inhibiting soil respiration, while Carnobacterium, Propionibacterium, and Clostridium played greater roles in soil respiration under the simulated acid rain. Soil pH, available potassium, soluble organic carbon and microbial biomass carbon were closely and positively correlated with the soil microbial community structure under simulated acid rain treatment, while alkali nitrogen and available phosphorus were negatively correlated with the soil microbial community structure. In general, simulated acid rain can significantly inhibit soil respiration in Moso bamboo forests, and change soil microbial community structure and diversity. These results provide theoretical basis for further study on the response mechanism of soil ecosystem of Moso bamboo forest to environmental problems.
  • DownLoad:Effects of simulated acid rain on soil respiration and microbial diversity in Moso bamboo forest in subtropical China.PDF
  • Effect of soil-rock interface on soil organic matter hydrolase activity under different disturbance gradients in Karst Critical Zone
  • Authors:WANG Siqi, XUE Yafang, WANG Ying, YANG Liyang, ZHANG Yongqing, TIAN Jing
  • Abstract:Soil enzymes play an important role in the material cycle and energy flow of soil ecosystem, and are strongly affected by land use patterns. Karst area has the characteristics of wide exposed area of rock and shallow discontinuity of soil layer, and increased with the aggravation of human interference intensity. However, the progress on the response of soil enzymes related to carbon and nitrogen cyclingto exposed rock (soil rock interface) under different land use disturbance gradients is weak. In this study, we selected Chenqi and Tianlongshan river basins in karst area of Guizhou Province as the research areas to explore the differences of soil organic matter hydrolase activities and their driving factors of soil-rock interface under four different disturbance gradients: primary forest, secondary forest, abandoned farmland and cultivated land. The results showed that: (1) when the land use pattern changed from forest to abandoned farmland or cultivated land,the content of soil organic carbon (SOC), total nitrogen (TN), nitrate nitrogen (NO3--N), ammonium nitrogen (NH4+-N) and SOC/TN decreased with the increase of human disturbance intensity. The pH, SOC and NH4+-N contents of the soil-rock interface were higher in the four soils with different disturbance intensities. (2)Soil enzyme activities differed significantly between soil-rock interface and bulk soil under different disturbance gradients. The activities of β-1,4-glucosidase (βG), β-1,4-xylanase (βX), cellulose disaccharide hydrolase (CBH) and α-1,4-glucosidase (αG) related to carbon cycle were higher in abandoned farmland and cultivated land than in primary and secondary forests.The β-1,4-N-acetylglucuronidase (NAG) and leucine aminopeptidase(LAP) related to nitrogen cycle showed higher activity in primary forest and abandoned farmland. All the hydrolases had the highest activity at the rock-soil interface of abandoned farmland. (3) RDA analysis showed that the content of dissolved organic carbon (DOC) had the greatest influence on soil hydrolase activity, and contributed to the variation of 33.4% (P=0.002). Soil pH, SOC and NH4+-N were significantly correlated with enzyme activities. In conclusion, land use and rock exposure significantly affected the physical and chemical properties and hydrolase activity of soil; at the same time, the soil rock interface of the abandoned farmland maintained a high carbon and nitrogen turnover enzyme activities, which reflected that the nutrient cycling function of soil still existed under long-term restoration. The results further indicates that returning farmland to forest and grassland are of great significance to ecosystem restoration and sustainable use of land resources in karst areas.
  • DownLoad:Effect of soil-rock interface on soil organic matter hydrolase activity under different disturbance gradients in Karst Critical Zone.PDF
  • Reconstruction of above-ground biomass and net primary productivity of dominant tree species in Guizhou forests over past five decades based on tree-ring data
  • Authors:LIU Libin, XU Haiyang, GUO Yinming, LIANG Hui, LU Xiaoming, ZHANG Hui, LIANG Eryuan, NI Jian
  • Abstract:Tree-ring widths and allometric functions were used to reconstruct above-ground biomass (AGB) and net primary productivity (ANPP) of six dominant tree species (Tianlongshan Mt.: Platycarya strobilacea, Machilus cavaleriei; Maolan: Platycarya strobilacea, Pinus massoniana; Leigongshan Mt.: Pinus armandii, Pterostyrax psilophyllus) in three typical forests of Guizhou Province (karst evergreen and deciduous broadleaved mixed forests in two sites and another site of typical evergreen broadleaved forest). Similarity and dissimilarity of AGB and ANPP of different tree species, as well as the effects of climate change in the past five decades on ANPP were compared between karst and non-karst regions. The results showed that coniferous trees presented wider mean tree-ring widths than broadleaved trees. The mean ring-widths of coniferous trees and broadleaved trees in karst regions were narrower than those in non-karst region. The trees in karst regions indicated higher AGB and larger variation ranges than those in non-karst region. The ANPP of broadleaved trees and coniferous trees in karst regions were 2.4 ±1.2 kg a-1 individual-1 and 4.6 ±4.1 kg a-1 individual-1, respectively in the past five decades, which were significantly lower than those in non-karst region (5.6 ±4.8 kg a-1 individual-1 and 12.4±7.7 kg a-1 individual-1, respectively). Tree ANPP increase in karst regions was more related to mean annual temperature than growing season precipitation, and tree ANPP increase in non-karst region showed significant relationships with both mean annual temperature and growing season precipitation. ANPP of coniferous trees was more sensitive to climate change than that of broadleaved trees in both karst and non-karst regions.
  • DownLoad:Reconstruction of above-ground biomass and net primary productivity of dominant tree species in Guizhou forests over past five decades based on tree-ring data.PDF
  • Effects of simulated precipitation addition on growth and root morphological characteristics of desert plant seedling
  • Authors:LI Xinle, ZHANG Jingbo, DONG Xue, XIN Zhiming, DUAN Ruibing, LUO Fengmin, LI Yonghua
  • Abstract:Precipitation is the most important limiting factor for processes and functions of desert ecosystems and desert plant seedlings are extremely sensitive to precipitation changes during the growing season. In order to explore the response of desert plant seedlings to future precipitation pattern changes, two typical desert plant seedlings (Nitraria tangutorum and Artemisia ordosica) in Ulan Buh desert were selected as research objects. The artificial simulated precipitation addition experiment was conducted with five different gradients (CK: natural precipitation, A: +25% precipitation, B: +50% precipitation, C: +75% precipitation, D: +100% precipitation) based on the precipitation of growing season from June to September to study the growth of two plant seedlings and the response of root morphological characteristics to precipitation changes. The results showed that 1) different precipitation treatments had significant effects on the shoot growth of Nitraria tangutorum and Artemisia ordosica seedlings (P <0.05). The height, average crown, and base diameter of Nitraria tangutorum and Artemisia ordosica seedlings were significantly higher than the CK and increased with the amount of precipitation(except for the base diameter of Nitraria tangutorum).2) There were significant differences in total root length, total surface area, average diameter, total volume, number of root tips and number of branches between precipitation treatments(P <0.05). For the Nitraria tangutorum seedlings, the root parameters of B and C treatments were significantly greater than those of CK, A and D treatments, and there was no significant difference between B and C treatments (except for the average diameter); for the Artemisia ordosica seedlings, the total root length, total surface area, total volume, number of root tips and number of branches increased gradually with the increase of precipitation, while the average diameter increased first and then decreased, and reached the maximum under B treatment.3) Precipitation addition treatment significantly reduced the root-shoot ratio of Nitraria tangutorum seedlings, but had no effect on the seedlings of Artemisia ordosica, and the root-shoot ratio of Nitraria tangutorum seedlings was significant greater than the seedlings of Artemisia ordosica.4) The roots diameter of two seedlings were mainly distributed in 0-0.5mm and 0.5-1mm, and the ratio of fine root (<2mm) reached the maximum value under B and D treatment, respectively. It suggested that Nitraria tangutorum and Artemisia ordosica seedlings could adjust shoot growth and root morphology to adapt precipitation changes.
  • DownLoad:Effects of simulated precipitation addition on growth and root morphological characteristics of desert plant seedling.PDF
  • Simulating evapotranspiration of the desert riparian Populus euphratica Olive. forest based on an improved dual-source model
  • Authors:GAO Guanlong, FENG Qi, LIU Xiande
  • Abstract:Evapotranspiration (ET) is a key component of water cycles and energy balance, quantification of which is important for revealing the eco-hydrological processes in arid and semi-arid areas. Taking the desert riparian Populus euphratica Olive. forest as the study object, we studied the diurnal and phonological variations of ET based on the data measured from the eddy covariance instrument, simulated ET of the P. euphratica forest using an improved dual-source Penman-Monteith-Priestley-Taylor (PM-PT) model and analyzed the parameter sensitivity. Results showed that: (1) the diurnal variations of ET of the P. euphratica forest both increased firstly, and then decreased during the growing seasons in 2014 and 2015, respectively. With the enhancement of solar radiation in the forenoon, the temperature raised gradually, ET increased and peaked at about 12:00. Afterwards, solar radiation weakened, the temperature decreased gradually, the relative humidity increased and the vapor pressure deficit decreased, and ET decreased accordingly. (2) The seasonal variations of ET of the P. euphratica forest increased firstly, and then decreased. Total ET during the growing seasons in 2014 and 2015 were 612 mm and 658 mm, respectively. ET accumulated in fruit and seed dispersal periods were the main parts, especially in fruit period. The accumulated ET were 316 mm and 348 mm, accounting for 51.65% and 52.87% of total ET in each growing season in 2014 and 2015, respectively. The average values of ET in seed dispersal period were slightly lower than those in fruit stage. The accumulated ET were 261 mm and 271 mm, accounting for 42.71% and 41.12% of total ET in each growing season in 2014 and 2015, respectively. Because the leaves of P. euphratica were not fully formed in leaf development stage and the leaf activity decreased gradually in leaf discoloration stage, the average values of ET in both stages were the lowest. (3) Compared with the traditional dual-source Shuttleworth-Wallace (SW) model, the improved dual-source PM-PT model is optimized in terms of the model structure and parameter numbers, and its accuracy is also higher. (4) The improved PM-PT model had the greatest sensitivity to net radiation.
  • DownLoad:Simulating evapotranspiration of the desert riparian Populus euphratica Olive. forest based on an improved dual-source model.PDF
  • Estimation of soil erosion based on the RUSLE model in China
  • Authors:LI Jialei, SUN Ranhao, XIONG Muqi, YANG Guocheng
  • Abstract:The revised universal soil loss equation (RUSLE) is an empirical model to predict water erosion (soil erosion); however, the model calculation has limitations at large scale. We calibrated the rainfall erosivity factor (R factor) based on climate zones and the cover-management factor (C factor) based on land-cover types and agricultural crops. The support practice factor (P factor) was also revised based on crop types and land slope. Using the RUSLE, we estimated the annual soil erosion reference values in China in 2000, 2005, 2010 and 2015. The results indicate that: (1) in 2015, the hotspots with major erosion rates are predicted to occur in downstream Yangtze River, Yunnan-Guizhou Plateau, Loess Plateau, and the foothill area of Kunlun Mountains, accounting for 9.65% of the statistical area. (2) The hotspots with a rapid increase of erosion during the study period are located in the arable area of Xinjiang, Sichuan Basin, southeastern Yunnan-Guizhou Plateau, Yangtze Plain and Northeast Plain, which cover 10.36×104 km2. (3) The erosion areas with a significant decrease are distributed in the southern and eastern Loess Plateau, Qinling Mountains and Southeast coast of China. These regions cover an area of 13.60×104 km2. By calibrating the parameters of RUSLE model, this study obtained the spatial and temporal differentiation rules of soil water erosion at a national scale, which could provide a basis for formulating soil restoration measures in different regions.
  • DownLoad:Estimation of soil erosion based on the RUSLE model in China.PDF
  • Simulating the leaf stomatal conductance of the desert riparian Tamarix ramosissima Ledeb. based on three empirical models
  • Authors:GAO Guanlong, FENG Qi, LIU Xiande, LI Wei
  • Abstract:Stomata are accesses of moisture and CO2 and gateways for evaporation and gas exchange. Estimating leaf stomatal conductance (gs) is pivotal for the further estimation of transpiration rates as well as the energy and mass balances between the air and plants. Based on the data collected from the Alxa Comprehensive Observation Field of the Community Hydrothermal Balance in the lower reach of the Heihe River, we measured the gs of Tamarix ramosissima and analyzed diurnal variations under clear weather conditions using a LI-6400 portable photosynthesis system. Meanwhile, by combining micro-meteorological and physiological data, we modeled the gs of T. ramosissima based on the three most commonly used empirical models. The results showed that: (1) the diurnal variations of the gs of T. ramosissima first increased and then decreased. With the gradual enhancement of solar radiation in the morning, the temperature and the transpiration rate gradually increased, and gs increased accordingly, peaking between 10:00 and 12:00 h. On most observational days, gs fluctuated to a certain extent around 12:00 h, and this was due to the high temperatures that caused the stoma to close. Afterwards, solar radiation weakened, air temperature decreased, the relative humidity in the air increased, the water vapor pressure inside and outside the leaves decreased, and gs decreased, which led to a decrease in the transpiration rate. (2) We modeled gs using three commonly used (semi-) empirical models (Jarvis; Ball-Woodrow-Berry, BWB; and Ball-Berry-Leuning, BBL), and we concluded that the Jarvis model always gives the most reliable performance with a modified coefficient of efficiency (E1), modified index of agreement (d1), and determination coefficient (R2) at values of 0.775 and 0.891, 0.887 and 0.945, and 0.590 and 0.645 in 2015 and 2016, respectively. (3) The accuracy between the BWB and BBL models was similar, indicating that there was no obvious difference between vapor pressure and relative humidity that influenced gs.
  • DownLoad:Simulating the leaf stomatal conductance of the desert riparian Tamarix ramosissima Ledeb. based on three empirical models.PDF
  • The differences between extracting vegetation information from GF1-WFV and Landsat8-OLI
  • Authors:ZHAO Linlin, ZHANG Rui, LIU Yanxu, ZHU Xicun
  • Abstract:With the development of remote sensing technology, medium and high resolution images are playing an important role in vegetation monitoring. In order to define the advantages of high resolution sensors in extracting vegetation information of different ecosystems, this research select urban and forest as target area in Olunchun autonomous banner, Inner Mongolia. Two kinds of sensor images, GF1-WFV and Landsat8-OLI, were used as comparison dataset to explore the difference of vegetation extracting using different spatial resolution in these two ecosystems. The results showed that: (1) compared with GF-1, Landsat 8 showed opposite overestimation and underestimation of its vegetation index in urban areas and forest areas, while the Normalized Difference Vegetation Index (NDVI) and Soil-adjusted Vegetation (SAVI) of GF-1 in urban areas were 5.69% and 1.41% higher than that of Landsat 8, and 0.77% and 5.86% lower in forest areas. (2) High-resolution images avoided the green vegetation of urban (71.30% and 71.31% of GF-1 vegetation, 58.28% and 58.30% of Landsat 8) and bare land and roads of forest (94.97% and 94.92% of GF-1 vegetation, 95.00% and 94.99% of Landsat 8) were omitted. (3) In terms of graded area, compared with GF-1, Landsat 8 underestimates 6.67% and 6.77% of low coverage levels in urban areas, and overestimates 12.11% and 12.47% of high coverage levels in forest areas. This research reflects it is more necessary to use high-resolution images as vegetation monitoring tools in low green built-up areas and high density forest areas.
  • DownLoad:The differences between extracting vegetation information from GF1-WFV and Landsat8-OLI.PDF
  • Variations of undergrowth species diversity on Camellia oleifera plantations in Guangxi
  • Authors:XIA Yingying, HAO Bingqing, JIANG Zepeng, LIU Kai, MAO Zijun
  • Abstract:In the present study, we selected seven typical Camellia oleifera plantations in Guangxi to examine the diversity of their undergrowth species. Specially, we focused on the study of its species composition, structural features and diversity. Our results are as follows. First, Sanjiang (SJ) had the most abundance number of families, genera and species of shrubs and herbs in the C. oleifera community, whereas Bama (BM) and Laibin (LB) had relatively least abundance number. In addition, the common species were dominant only in the BM shrubs layer, while the dominant species of shrubs and herbs in all other communities were cross-species. Secondly, the difference in Margalef index was only significantly among shrubs diversity. In contrast, the difference in the indexes of Margalef, Simpson and Shannon-Wiener for herbs diversity were all significant. Thirdly, the regression analysis showed that the relationship between latitude and numbers of single-species in shrubs layer, families, genera, species, and single-species in herbs layer and the total genera and species exhibited a quadratic model. Similarly, the tendency between the average annual temperature and the numbers of families, genera, species, and single-species in herbs layer, the effective accumulative temperature and the numbers of genera, species, and single-species in herbs layer, the average annual rainfall and the number of single-species in shrubs layer also showed quadratic model. Finally, the species in different C. oleifera communities were observed to show a few similarities. Cluster analysis with similarity metrics showed that the undergrowth species of the plantations in SJ, Babu district in Hezhou (HZ), Cenxi soft branch Camellia oleifera seed orchard (CX) and Nanning (NN) were classified into the same class, while the undergrowth species of the plantations in Fengshan (FS), BM and LB belonged to another class. In summary, the regional variation of undergrowth species in Guangxi C. oleifer plantations was closely related with the habitat heterogeneity in different areas.
  • DownLoad:Variations of undergrowth species diversity on Camellia oleifera plantations in Guangxi.PDF
  • Evolution law and attribution analysis of potential evapotranspiration in Liaoning Province
  • Authors:CAO Yongqiang, QI Jingwei, WANG Fei, LI Linghui, LU Jie
  • Abstract:Based on daily meteorological data from 21 meteorological stations in Liaoning Province from 1965 to 2017, Penman-Monteith method, wavelet analysis method, sensitivity coefficient and factor analysis method were used to explore the spatiotemporal variation of potential evapotranspiration and the quantitative analysis of its main meteorological elements. The results show that: (1) from the perspective of the temporal change, the potential evapotranspiration in Liaoning Province has a significant downward trend, with a change rate of 2.89 mm/a and a multi-year average of 955.82 mm. The potential evapotranspiration of the 20 meteorological station has been decreasing, but that of one meteorological station has been increasing. On the spatial scale, the potential evapotranspiration of Liaoning Province decreased from west to east. (2) The potential evapotranspiration is most sensitive to relative humidity and least sensitive to minimum temperature. (3) The average wind speed is the meteorological factor that has the greatest influence on the potential evapotranspiration, and the relative humidity has a negative correlation with the potential evapotranspiration.
  • DownLoad:Evolution law and attribution analysis of potential evapotranspiration in Liaoning Province.PDF

您是本站第 104439296 位访问者

Copyright © 2005-2019   
地址:北京海淀区双清路18号
  邮编:100085    电话:010-62941099
  E-mail : shengtaixuebao@rcees.ac.cn
本系统由提供技术支持