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Procapra picticaudata is an ungulate endemic to the Tibetan Plateau and is widely distributed in the Three-River-Source region. Predicting the seasonal variations in habitat suitability and understanding the effects of environmental variables on habitat use by this species will help formulate effective conservation strategies and clarify its niche characteristics. Based on point records of the occurrence collected during repeated field surveys in winter (January 2019) and summer (August 2019), we used MaxEnt model to predict the differences in habitat suitability and the distribution pattern of the P. picticaudata in the Three-River-Source region using eight preselected environmental variables. We further explored the influence of those variables on the P. picticaudata ' distribution pattern using environmental response curves. The results showed that the average area under the receiving operator curve values in winter and summer was 0.901±0.023 and 0.882±0.024, respectively, with a good accuracy of fitness. The total area of suitable habitat for P. picticaudata in winter and summer was 6.83×10 4 and 9.78×10 4 km 2 , respectively. The area of suitable habitats in summer increased significantly compared with winter. There was a tendency for P. picticaudata to spread to the south of the Yangtze River Source Park and the Yellow River Source Park in summer. The spatial patterns of habitat suitability in both winter and summer took Three-River-Source National Park as the high-value center and decreased around it. The seasonal average temperature, altitude, population density, and slope were the main environmental variables affecting the distribution of P. picticaudata both in winter and summer. The higher temperatures in summer allowed the suitable P. picticaudata habitats to extend into areas above 5000 m in altitude, and to areas with slopes of less than 25°, compared with winter. The expansion of human activities in summer encroached on the suitable habitat of P. picticaudata .

To understand the synergetic features of economy, society, and ecology in cities, we established an urban ecological-economic-social synergetic index evaluation system from three aspects (per capita green area, per capita GDP, and life expectancy per capita) and created an urban ecological-economic-social synergetic index eva-luation method. We analyzed the synergetic features by comparing the ecological-economic-social synergetic index and comprehensive function scores of 35 typical cities in China. The differences in ecological-economic-social synergy and function score for different city sizes and administrative divisions were investigated, while the synergy level of cities were classified. The results showed that the average ecological-economic-social synergetic index of 35 cities in China was 28.79, with the highest of 3.83 and the lowest of 63.04 in 2016. The synergetic index, urban econo-mic function, and social function were significantly positively correlated with urban population sizes and economic sizes. There were significant differences in synergetic index among cities with different population sizes, economic sizes, and administrative functions. The urbanization in China was still in the status of functional imbalance. Urban development was conducive to improve cities' function, but did not effectively improve the synergy of ecology, economy, and society. The ecological function of cities significantly affected urban synergy, which indicated that the poor urban ecological function was the main restrictive factor for urban synergy in China.

This study assessed the dynamics of lakes in the north Tanggula Mountains in Tibet (NT area) and predicted the spatial changes. We used object-oriented classification and a spectral-angle vector change detection method to generate ecosystem distribution data for the NT area at five-year interval between 2000 and 2015. Based on this dataset, we measured the spatial pattern of lake dynamics and related geophysical and meteorological factors. A boost regression tree model was used to examine the contribution of these variables to lake area change, which were further used in a GEOMOD model to predict the distribution of lakes in 2030. The results showed that the area of lakes increased by 14.2% between 2000 and 2015, which was one of the main forms of ecosystem change in the NT area. In the study region, the area of 10 lakes out of the total 15 lakes with an area greater than 10 km 2 increased and that of another five lakes decreased with a relatively low shrinkage ratio. Both the mean site area and site number of lakes increased, and the percentage of large lake sites increased slightly. Lakes located in areas with high altitude, high slope, low tempe-rature, low precipitation, or near glaciers had a higher probability of size increase. Locales near the current lake sites with low temperature, precipitation, and slope tended to become new parts of extant lakes. Following the trend of the last 15 years, lakes in the NT area would increase by 119 km 2 by 2030, with the main form of lake expansion changing from inundation of area around large lakes to area around smaller sites.

Despite broad interest in using payment for ecosystem services to promote changes in the use of natural capital, there are few expost assessments of impacts of payment for ecosystem services programs on ecosystem service provision, program cost, and changes in livelihoods resulting from program participation. In this paper, we evaluate the Paddy Land-to-Dry Land (PLDL) program in Beijing, China, and associated changes in service providers' livelihood activities. The PLDL is a land use conversion program that aims to protect water quality and quantity for the only surface water reservoir that serves Beijing, China's capital city with nearly 20 million residents. Our analysis integrates hydrologic data with household survey data and shows that the PLDL generates benefits of improved water quantity and quality that exceed the costs of reduced agricultural output. The PLDL has an overall benefit-cost ratio of 1.5, and both downstream beneficiaries and upstream providers gain from the program. Household data show that changes in livelihood activities may offset some of the desired effects of the program through increased expenditures on agricultural fertilizers. Overall, however, reductions in fertilizer leaching from land use change dominate so that the program still has a positive net impact on water quality. This program is a successful example of water users paying upstream landholders to improve water quantity and quality through land use change. Program evaluation also highlights the importance of considering behavioral changes by program participants.

Two city ecosystem research stations were selected for continuous monitoring of atmospheric fine particulate matter (PM2.5) concentration from June to September 2008, when the Beijing Olympic Games was held. The relationship between meteorological factors, artificial control management measures and PM2.5 dynamic characteristics were analyzed. The results showed that the daily average concentration of PM2.5 at RCEES Station, which is near the 5th North Ring, was 0.067 mg x m(-3) during the study period, and the particle concentration during the Olympic Games was 0.060 mg x m(-3), which was decreased by about 26% compared with the content before the Olympic Games (0.081 mg x m(-3)). As for JX Station located in the 2th South Ring, its daily average concentration of PM2.5 was 0.078 mg x m(-3). Similar to RCEES Station, PM2.5 average content during the Olympic Games (0.069 mg x m(-3)) was 27% lower compared with the content before the Olympic Games (0.095 mg x m(-3)). Two peaks could be found when daily distribution of PM2.5 was displayed, one appeared between 08:00 and 10:00 (the average content for RCEES and JX were 0.068 and 0.089 mg x m(-3), respectively), and the other appeared at 20:00-22:00, which could be attributed to traffic emission and road dust pollution, especially the emission from the growing number of cars in rush hours. Meteorological condition during the whole period was typical in summer in Beijing with both high temperature and humidity. Correlation analysis revealed that the concentrations of PM2.5 had a positive correlation with the air temperature (P < 0.01), while it had no significant relationship with wind speed, relative humidity or precipitation (P > 0.05). Our monitoring results suggested that the artificial air pollution control strategies were effective measures for air pollution control during 2008 Beijing Olympic Game.

Sustainable ecosystem services supply is the basis of regional sustainable development, and human beings can satisfy and improve their well-being through ecosystem services consumption. To understand the relationships between ecosystem services supply and consumption and human well-being is of vital importance for coordinating the relationships between the conservation of ecosystem services and the improvement of human well-being. This paper summarized the diversity, complexity, and regionality of ecosystem services supply, the diversity and indispensability of ecosystem services consumption, and the multi-dimension, regionality, and various evaluation indices of human well-being, analyzed the uncertainty and multi-scale correlations between ecosystem services supply and consumption, and elaborated the feedback and asynchronous relationships between ecosystem services and human well-being. Some further research directions for the relationships between ecosystem services supply and consumption and human well-being were recommended.

The diverse natural environment in China causes the spatial heterogeneity of China population distribution. It is essential to understand the interrelations between the population distribution pattern and natural environment to enhance the understanding of the man-land relationship and the realization of the sustainable management for the population, resources, and environment. This paper analyzed the China population distribution by adopting the index of population density (PD) in combining with spatial statistic method and Lorenz curve, and discussed the effects of the natural factors on the population distribution and the interrelations between the population distribution and 16 indices including average annual precipitation (AAP), average annual temperature (AAT), average annual sunshine duration (AASD), precipitation variation (PV), temperature variation (TV), sunshine duration variation (SDV), relative humidity (RH), aridity index (AI), warmth index ( WI), > or = 5 degrees C annual accumulated temperature (AACT), average elevation (AE), relative height difference (RHD), surface roughness (SR), water system density (WSD), net primary productivity (NPP), and shortest distance to seashore (SDTS). There existed an obvious aggregation phenomenon in the population distribution in China. The PD was high in east China, medium in central China, and low in west China, presenting an obvious positive spatial association. The PD was significantly positively correlated with WSD, AAT, AAP, NPP, AACT, PV, RH, and WI, and significantly negatively correlated with RHD, AE, SDV, SR, and SDTS. The climate factors (AAT, WI, PV, and NPP), topography factors (SR and RHD), and water system factor (WSD) together determined the basic pattern of the population distribution in China. It was suggested that the monitoring of the eco-environment in the east China of high population density should be strengthened to avoid the eco-environmental degradation due to the expanding population, and the conservation of the eco-environment in the central and west China with vulnerable eco-environment should also be strengthened to enhance the population carrying ability of these regions and to mitigate the eco-environmental pressure in the east China of high population density.

Various land uses and enormous environmental pressures are characteristics of suburbs. Full understanding of suburban soil pollution is necessary for urban planning and development. In this study, 167 surface soil samples (0-20 cm) located in suburbs of Beijing between the fifth and sixth ring road were collected based on the 3 km x 3 km grids. The purpose of our investigation is to reveal the accumulating characteristics of As in Beijing suburbs. Results showed that arsenic contents in suburban soils of Beijing ranged from 2.89 mg x kg(-1) to 11.38 mg x kg(-1), with mean of 7.11 mg x kg(-1). The means were in the range of the background values reported in late 1990s, but the values of each quantile were lower than the soil background values reported in early 1980s. Factor analysis suggested that As in Beijing suburban soil shared the same group as those elements coming from parent materials such as Co, Mn and Ni. The spatial distribution map using Kriging interpolation showed that As contents in northwestern, eastern and southeastern parts were higher than those in northeastern and southwestern parts. Those plots with contents of the highest 25% were all located near the pollution sources, while most of those with the lowest 25% contents located far from the pollution sources. Comparison of As contents in different land uses showed that human activities had influence on the accumulation of As in soils. Inhabitation areas and agricultural fields had higher As contents than the green lands and vacant lands. Pollution sources significantly affected the accumulation of As in soils of inhabitation areas, green lands and vacant lands. Arsenic contents in soils near factories were significantly higher than those far from factories and traffic corridors. To sum up, the spatial distributions of As contents in soils in Beijing suburban area were generally determined by the distributions of parent materials, while human activities increased the accumulation of As in soils to some degree.

Aiming at the features of Haihe River basin, and by using RS and GIS technologies in combining with qualitative and quantitative analyses, a regionalization was conducted on the ecological function of the basin. The Haihe River basin could be divided into 5 ecoregions, 24 sub-ecoregions, and 114 eco-functional zones. Furthermore, 11 critical eco-functional zones were identified, according to the dominant functions (water conservation, soil conservation, wind prevention and sand fixation, and biodiversity protection) at basin scale. This regionalization made clear the regions important for the ecological security of Haihe River basin, which could guide the orderly exploitation and utilization of natural resources and the rational distribution of industries, offer scientific basis for the ecological environment protection, and maintain the ecological security of the basin.

A total of 140 endangered species in Hainan Island were selected as indicator species, and their spatial distribution patterns were analyzed by using mechanism habitat model. Based on the iterative operation with systematic conservation planning tool MARXAN, the priority areas of these species were identified and evaluated. The priority areas had an area of 5383.7 km2, accounting for 15.6% of the total land area of the Island, and mainly distributed in some forest regions (Yinggeling, Jianfengling and Wuzhishan) and in northern part water source regions. In the priority areas, the conservation proportion of 11 1st grade indicator species habitats occupied at least 65% of all the habitats. Through the gap analysis of priority areas and current nature reserves, it was suggested that an expansion of Jianfengling, Yinggeling-Limushan, and Wuzhishan-Diaoluoshan nature reserves and the establishment of Baolonglinchang-Linbiling-Fuwanling protection system should be made, and the protection areas for water source conservation and endangered species should be established in the northern part of the Island.

According to the connotation of ecosystem services, an evaluation index system for the agro-ecosystem services in the Haihe River basin of China was established, and the economic value of the agro-ecosystem services and environmental costs were evaluated by the methods of market valuation, shadow price, and opportunity cost. In 2005, the total environmental benefit value of the agro-ecosystem services in the basin was 180. 264 billion RMB, with the regulation value of 79.416 billion RMB (44.06%) and the supporting value of 100.848 billion RMB (55.94%). Provision and cultural services were not considered in this research. From the viewpoint of functional type, the ecosystem services value from high to low was in the order of oxygen release > water conservation > nutrient cycling > soil conservation > waste purification > environmental purification > carbon sequestration > straw returning. The environmental costs of the agro-ecosystem were quite high (42. 293 billion RMB), among which, fertilizer loss was 427.42 x 10(4) t, equivalent to 15.191 billion RMB, and greenhouse gases production was calculated as 3599.65 x 10(4) t CO2, equivalent to 27. 102 billion RMB.

The 39-item Parkinson's Disease Questionnaire (PDQ-39) has been tested in many languages, but not in Chinese mainland. We aimed to assess the Chinese (mainland) version of the PDQ-39. Seventy-one subjects with Parkinson's disease (PD) completed the PDQ-39 and the Medical Outcomes Study 36-item Short Form Health Survey (SF-36). All subjects were retested with the PDQ-39 a week later. The united Parkinson's disease rating scale (UPDRS) and the Hoehn and Yahr (H & Y) scale were also used to evaluate the subjects. Reliability was assessed by Cronbach's alpha and intra-class correlation coefficient (ICC). Validity was examined in terms of agreement with SF-36, UPDRS, and H & Y scales. The Chinese (mainland) version of the PDQ-39 demonstrated acceptable reliability (Cronbach's alpha: 0.84-0.88; ICC: 0.56-0.82). The item-total correlations (0.33-0.88) and scaling success rates (77.56%) indicated satisfactory convergent and discriminant validity of the PDQ-39 items. The correlations between related constructs of the PDQ-39 and UPDRS (r=0.44-0.68) and between those of the PDQ-39 and SF-36 (r=(-0.46)-(-0.69)) were all statistically significant (P<0.01). Except for stigma, cognitions, and bodily discomfort, all other dimensions of the PDQ-39 significantly discriminated patients at different H & Y stages indicated by the H & Y scale. Although our observations indicate that some problematic subscales of this version of the PDQ-39 could be improved upon, this study suggests acceptable reliability and validity of the Chinese (mainland) version of the PDQ-39.

Straw returning is considered to be one of the most promising carbon sequestration measures in China's cropland. A compound model, namely "Straw Returning and Burning Model-Expansion" (SRBME), was built to estimate the net mitigation potential, economic benefits, and air pollutant reduction of straw returning. Three scenarios, that is, baseline, "full popularization of straw returning (FP)," and "full popularization of straw returning and precision fertilization (FP + P)," were set to reflect popularization of straw returning. The results of the SRBME indicated that (1) compared with the soil carbon sequestration of 13.37 Tg/yr, the net mitigation potentials, which were 6.328 Tg/yr for the FP scenario and 9.179 Tg/yr for the FP + P scenario, had different trends when the full budget of the greenhouse gases was considered; (2) when the feasibility in connection with greenhouse gas (GHG) mitigation, economic benefits, and environmental benefits was taken into consideration, straw returning was feasible in 15 provinces in the FP scenario, with a total net mitigation potential of 7.192 TgCe/yr and the total benefits of CNY 1.473 billion (USD 216.6 million); (3) in the FP + P scenario, with the implementation of precision fertilization, straw returning was feasible in 26 provinces with a total net mitigation potential of 10.39 TgCe/yr and the total benefits of CNY 5.466 billion (USD 803.8 million); (4) any extent of change in the treatment of straw from being burnt to being returned would contribute to air pollution reduction; (5) some countermeasures, such as CH(4) reduction in rice paddies, precision fertilization, financial support, education and propaganda, would promote the feasibility of straw returning as a mitigation measure.

Based on the questionnaire of World Bank/World Wide Fund for Nature (WB/WWF) management effectiveness tracking tool, a survey was conducted in 535 China nature reserves to assess their management effectiveness, with the countermeasures suggested. The 535 nature reserves had an average score of 51.95, and 69.35% of them had a score less than 60, illustrating that the general management level of our nature reserves was relatively low. There was a significant difference (P < 0.01) in the scores of management effectiveness among the nature reserves of different class and established at different time, i. e., the higher class and the longer establishing time, the higher score of management effectiveness. However, no significant differences (P > 0.05) were observed in the scores among the reserves with different area and type. The average scores of management base, management mechanism, management behavior, and management effectiveness were 1.55, 1.44, 1.52, and 1.90, respectively. The indices (management of protection targets, condition assessment, reserve boundary, resource management, and management agency) had the highest average scores, while equipment use and maintenance, community co-management, budget sources, budget expending and management, and management system and regulations had the lowest ones. The management system for China nature reserves had been generally established, the major targets and their values had been successfully protected, but there were still many problems in the management of China nature reserves, such as management mechanism and management base construction. To improve the management effectiveness, some countermeasures should be taken, e. g., establishing rational distribution and management mechanisms of budgets, strengthening ability construction, and promoting community participation.

Based on the 1976, 1989, 2000 and 2005 remote sensing images and related meteorological data, the landscape pattern change and its ecological effect in Manas River Basin of Xinjiang in 1976-2005 were analyzed with GIS and FRAGSTATES. In the study period, the landscape pattern change in the Basin mainly manifested in the increase of farmland, grassland, and residential area while the decrease of forestland, wetland, desert, and snow and ice coverage. At landscape level, the patch number, landscape shape index, and contagion index increased, while Shannon's diversity index decreased; at class level, there was a greater difference in the heterogeneity index among different kinds of landscape, indicating a complexity of the landscape ecosystem. The landscape pattern change caused the negative ecological effect of wetland area shrinking, but some positive effects such as the decrease of evaporation and the increase of relative humidity. From 1976 to 2005, the wetland area decreased from 415.7 km2 to 297.4 km2, with a decrement of 28%, evaporation decreased by 0.91 mm x a(-1), and relative humidity increased by 0.037% x a(-1).

From the aspects of four ecological themes, i.e., ecological element, ecological process, ecological function and ecological destruction, an indicator framework including 16 indicators was developed to make an integrated assessment on the ecological quality of Beijing urban area. The weights of the indicators were determined by the methods of entropy weight, optimal state weight, and worst state weight, and the ecological element index (EEI), ecological process index (EPI), ecological function index (EFI), ecological destruction index (EDI), and composite ecological index (CEI) were computed by a weighted sum method and served as effective tools for analyzing the evolvement of the ecological quality of Beijing urban area from 1996 to 2005. The results showed that during the period of 1996-2005, the EEI of Beijing urban area did not display visible improvement and maintained a low level, far from the ideal state. The EPI and EFI increased dramatically, and approached to the ideal state in 2005. The EDI fluctuated within a low level, far from ideal state, and did not show an evolutionary trend. The CEI improved year after year, but was still low and did not reach the ideal state. The EPI, EFI, and CEI increased rapidly with economic development when the GDP per capita was less than US $ 3,000, but the decrease was decelerated after the GDP exceeded US $ 3,000. The EEI and EDI were less affected by economic development, but mainly restrained by the natural conditions and global and regional eco-environmental evolvement.

Final energy-carbon consumption by different sectors and fuel types in Beijing from 1995 to 2005 and energy structure were presented according to IPCC reference approach and statistical data. Specific discussion of energy-carbon consumption category of each industry in 2005 was given. From 1995 to 2005, total and per capita final energy-carbon consumption increased respectively by 71.5% and 38.4%, while final energy-carbon consumption intensity descended by 66.2%. The energy-carbon consumption of Industry was the highest and accounted for about 53.0%-68.0% of total energy-carbon consumption (an average of 14.59 Mt), followed by tertiary industry, which accounted for about 15.0%-30.5% (an average of 5.23 Mt). Moreover, compared with 1995, the energy-carbon consumption of urban residential life had increased 2.02 times in 2005. At present, energy-carbon consumption of Industry is still the predominant part, and the adjustment of industrial structure hasn't yet changed its position. The structure of final energy-carbon consumption in Beijing has become steady since 2002. Although energy structure adjustments were conducted, carbon consumption still increased with the increase of energy use.

The characteristics of environmental geochemistry of heavy metal pollutant cadmium (Cd) in the surficial soil of Guiyang, Guizhou, China was studied. The baseline concentration of Cd in soil and the geochemistry norms have been established to distinguish the nature or artificial influence on the environment. The statistical analysis indicated that the baseline of Cd in Guiyang was 0.068 mg/kg. Geoaccumulation index analysis indicated that the unpolluted surface soils accounts for 40%, and 19% between nonpollution to mid-pollution, 14% for mid-pollution, 19% between mid-pollution to severe pollution, 7% for severe pollution, only 1% between severe pollution to super severe pollution. The maximum of Cd contamination degree (CD) is 12.1. CD analysis indicated that the unpolluted surface soils accounts for 57.9%.

To quantify the variations of methane fluxes from different aquatic vegetation zones, two-year measurements were measured at different aquatic vegetation zones and water depths using static chamber technique during two growing season from April to October in 2003 and 2004. Results showed that the average emission flux of CH4 from Potamogeton pectinatus (submerged macrophyte) growing zones was (3.44 +/- 1.60) mg x (m2 x h)(-1), 78.06% lower than that from Phragmites australis (emergent macrophyte). Significant seasonal and diurnal variations of CH4 emission were observed for Phragmites community; however, the variations were minor for P. pectinatus. Sediment temperature at 5 cm and photosynthesis active radiation were important factors influencing seasonal and diurnal variations of CH4 fluxes from Phragmites zone. Annual methane flux from the lake was 1 024.6 t and 1 156.7 t in 2003 and 2004, respectively.

Airborne bacteria are important biological components of the aerosol. They have a close relation with human health. The much higher concentrations can result in kinds of microbial disease. Using BIOLOG identification technology, the study on the community structure and dynamics of airborne bacteria was carried out in three typical functional areas in Beijing by systemic site sampling. Results show that the gram positive bacteria contributing 80%-85% were much more than the gram negative bacteria. Amongst 47 genera of bacteria including 31 Gram positive bacteria and 16 Gram negative bacteria, Micrococcus, Staphylococcus, Bacillus, Corynebacterium, and Pseudomonas were dominant, and Micrococcus contributing 20%-30% was the most dominant genus. The concentration of airborne bacteria was significant lower in GGR than in CER and MTL. In a year, the bacterial concentrations of summer and autumn were much more than those of winter and spring in CER and MTL, and there were no significant variations of bacterial concentrations in GGR. In different periods, the lower concentration of airborne bacteria was exhibited at 13:00.

Precipitation is considered to be the primary resource limiting terrestrial biological activity in water-limited regions. Its overriding effect on the production of grassland is complex. In this paper, field data of 48 sites (including temperate meadow steppe, temperate steppe, temperate desert steppe and alpine meadow) were gathered from 31 published papers and monographs to analyze the relationship between above-ground net primary productivity (ANPP) and precipitation by the method of regression analysis. The results indicated that there was a great difference between spatial pattern and temporal pattern by which precipitation influenced grassland ANPP. Mean annual precipitation (MAP) was the main factor determining spatial distribution of grassland ANPP (r(2) = 0.61, P < 0.01); while temporally, no significant relationship was found between the variance of ANPP and inter-annual precipitation for the four types of grassland. However, after dividing annual precipitation into monthly value and taking time lag effect into account, the study found significant relationships between ANPP and precipitation. For the temperate meadow stcppe, the key variable determining inter-annual change of ANPP was last August May precipitation (r(2) 0.47, P= 0.01); for the temperate steppe, the key variable was July precipitation (r(2)= 0.36, P= 0.02); for the temperate desert steppe, the key variable was April-June precipitation (r(2)=0.51, P< 0.01); for the alpine meadow, the key variable was last September-May precipitation (r(2)= 0.29, P < 0.05). In comparison with analogous research, the study demonstrated that the key factor determining inter-annual changes of grassland ANPP was the cumulative precipitation in certain periods of that year or the previous year.

An investigation on fungal types, concentrations, and their dynamic variation in outdoor environments was carried out in three different functional areas around one year in Beijing. Results show that the fungal concentrations varied widely and the average was (1164.8 +/- 73.2) CFU x m(-3), ranging from 23.6CFU x m(-3) to 13 959.5 CFU x m(-3). The most common culturable airborne fungi in all seasons and all functional areas were Cladosporium , nonsporulating fungi, Alternaria, Penicillium and Aspergillus. The most dominant fungus was Cladosporium, which contributed to more than 1/3 of the total. The fungal levels in culture and education region (CER) and garden green region (GGR) were highest in the fall and summer, and lowest in the winter and spring, while the seasonal variation in main traffic line (MTL) was not significant. The fungal concentrations in CER and GGR were significantly higher than in MTL (p <0.05). No statistically significant difference exists between CER and GGR.

A biogeochemical model (DNDC) is combined with a plant ecological model to estimate N2O emission from rice paddy fields in the Yangtze River Delta region. The model is driven by local meteorological, soil, and physiological data and is validated for 1999 and 2000 at a site in the region, which showed that the simulated N2O emissions agree fairly well with the observed data. This adds some confidence in the estimated N2O emissions during 1950 and 2000 in the Hangzhou Region. A significant correlation between the N2O emissions and the population for the Hangzhou Region is found, which is due to a combination of increased application of fertilizers and cultivated area. Such a correlation can not be established for the whole Yangtze River Delta region when the data of both urban and rural areas are included. However, when the data from the heavily urbanized areas are excluded, a significant correlation between population and N2O emissions emerges. The results show clearly that both the temporal and the spatial N2O emissions have significant positive relationship with population under traditional farming practice. These results have implications for suitable mitigation options towards a sustainable agriculture and environment in this region.

This study improved the application of the Holdridge life-zone model to simulate the distribution of desert vegetation in China which gives statistics to support eco-recovery and ecosystem reconstruction in desert area. This study classified the desert vegetation into four types: (1) LAD: little arbor desert; (2) SD: shrub desert; (3) HLHSD: half-shrub, little half-shrub desert; (4) LHSCD: little half-shrub cushion desert. Based on the classification of Xinjiang desert vegetation, the classical Holdridge life-zone model was used to simulate Xinjiang desert vegetation's distribution and compare the Kappa coefficient result of the model with table of accuracy represented by Kappa values. The Kappa value of the model was only 0.19, it means the simulation result was poor. To improve the life-zone model application to Xinjiang desert vegetation type, a set of plot standards for terrain factors was developed by using the plot standard as the re-classification criterion to climate sub-regime. Then the desert vegetation in Xinjiang was simulated. The average Kappa value of the second simulation to the respective climate regime was 0.45. The Kappa value of final modeling result was 0.64, which is the better value. The modification of the model made it in more application region. In the end, the model's ecological relevance to the Xinjiang desert vegetation types was studied.

Carbon output through urban domestic garbage is one part of carbon cycle in urban ecosystem which is related to some environmental pollution. Researches on carbon output through urban domestic garbage is the foundational work on carbon cycle in urban ecosystem, but also can help to analyze the influences of residents' consumption on environment. Based on data got through sampling and collecting, the status and trend of carbon output through domestic garbage in Haikou was analyzed. The results showed that, the total carbon output through 26.92 x 104 t of domestic garbage is 10.51 x 104 t and the carbon output per capita everyday is 0.326 kg/(cap. d)(-1) in 2001. About 31% of the total carbon will be transferred into methane, carbon dioxide and organic matter in extravasate. About 69% of the total carbon will be sequestrated in landfill. Because 33% of the sequestrated carbon originate from atmosphere, urban domestic garbage may be a carbon sink. From 1991 to 1999, the carbon output through Haikou's domestic garbage is annually increasing by 9.55%, and the output of sequestrated carbon is annually increasing remarkably by 13.23%. The increase of carbon output is significantly correlated with the increase of expenditure per capita and population, which shows expenditure per capita and population have some effect on carbon output.

Limited water resources, increasing demand, low use efficiency, and serious pollution result in severe water resource difficult in China. The evaluation of addressing water problems and the search for effective countermeasures that ensure sustainable water use are key to China's sustainable development. The "compound water security" consists of food security, life security, environmental security, and economic security. By establishing a conceptual model, the water security of China has been simulated in terms of four scenarios called BAU (the business-as-usual scenario), TEC (the technology and economics scenario), IVL (the institution, values, and lifestyles scenario) and TSD(toward sustainable development) in this paper. The results indicated that water crises, especially water shortages, are being experienced now and will continue to do so for a relatively long time in China and that it is possible to reach a basic balance between supply and demand of water and grain under the TSD developing pattern by a series of approaches including technological innovation, policy adjustments, and behaviour inducement.