Regular quantitative assessments of regional ecological environment quality(EEQ)and driving force analyses are highly important for environmental protection and sustainable development.Northern China is a typical clim...Regular quantitative assessments of regional ecological environment quality(EEQ)and driving force analyses are highly important for environmental protection and sustainable development.Northern China is a typical climate-sensitive and ecologically vulnerable area,however,the changes in EEQ in this region and their underlying causes remain unclear.Traditional evaluations of EEQ rely primarily on the remote sensing ecological index(RSEI),which lacks assessments of indicators such as greenness(NDVI),humidity(WET),heat(LST),and dryness(NDBSI).To address these issues,this study employs the principal component analysis method and the Google Earth Engine to construct an RSEI suitable for long-term and large-scale applications and analyzes the spatio-temporal variations in the RSEI,NDVI,WET,NDBSI,and LST.Additionally,geographical detectors are utilized to analyze the driving factors affecting EEQ.The results indicate the following.(1)The RSEI shows a fluctuating upward trend,with an average value of 0.4566,indicating a gradual improvement in EEQ.The EEQ exhibited significant spatial heterogeneity,with a pattern of lower values in the west and higher values in the east.(2)The NDVI and WET exhibit fluctuating increasing trends,indicating improvements in both indices.The NDBSI shows a fluctuating decreasing trend,whereas the LST presents a fluctuating increasing trend,suggesting an improvement in the NDBSI and a slight deterioration in the LST.NDVI and WET demonstrate a spatial pattern characterized by low values in the west and high values in the east.NDBSI and LST demonstrate a spatial pattern characterized by low values in the east and high values in the west.(3)Land use types and precipitation are the primary driving factors influencing the spatial differentiation of the EEQ.The explanatory power of these driving factors significantly increases under their interactions,particularly the interaction between land use types and other driving factors.This study fills the gap in existing EEQ evaluations that analyze only the RSEI without considering the NDVI,WET,NDBSI,and LST.The findings provide new insights for EEQ assessments and serve as a scientific reference for environmental protection and sustainable development.展开更多
To conduct a comprehensive analysis of the current status of water environment quality in Yilong Lake,a systematic study was undertaken to characterize the evolution of water quality.This study utilized monthly data o...To conduct a comprehensive analysis of the current status of water environment quality in Yilong Lake,a systematic study was undertaken to characterize the evolution of water quality.This study utilized monthly data on water quality indicators collected from three monitoring sections of Yilong Lake between 2016 and 2023,employing the Mann-Kendall trend test and ArcGIS spatial interpolation technique.The results indicated that the five-day biochemical oxygen demand(BOD5),total nitrogen(TN),and chlorophyll a(Chla)exhibited an overall increasing trend,whereas other indicators demonstrated a decreasing trend.The permanganate index(PI),chemical oxygen demand(COD),TN,and Chla were observed in the following order:east of the lake>middle of the lake>west of the lake.In contrast,the BOD5 and total phosphorus(TP)were ranked as west of the lake>east of the lake>middle of the lake.Additionally,ammonia nitrogen(NH3-N)was found to be in the order of east of the lake>west of the lake>middle of the lake,while transparency was ranked as west of the lake>middle of the lake>east of the lake.Urban domestic sewage,effluent from industrial parks,domestic waste generated by rural residents’production and daily activities,agricultural waste,wastewater from decentralized farming,domestic sewage,and point source discharges from the soybean processing industry are the primary contributors to the exceedance of water quality standards.The enhancement of a precise pollution control system,along with the regulation of pollution sources and the interception of pollutants,can significantly diminish the pollution load entering the lake.This approach is essential for the protection and restoration of river and lake ecosystems,thereby facilitating the gradual recovery of their ecological functions.Additionally,the implementation of ecological water replenishment and the recycling of water resources can improve the capacity of the water environment.Furthermore,bolstering scientific and technological support,as well as comprehensive supervision and assurance measures,is crucial to ensuring that water quality remains stable and adheres to established standards.展开更多
The Loess Plateau(LP),one of the most ecologically fragile regions in China,is affected by severe soil erosion and environmental degradation.Despite large-scale ecological restoration efforts made by Chinese governmen...The Loess Plateau(LP),one of the most ecologically fragile regions in China,is affected by severe soil erosion and environmental degradation.Despite large-scale ecological restoration efforts made by Chinese government in recent years,the region continues to face significant ecological challenges due to the combined impact of climate change and human activities.In this context,we developed a kernal Remote Sensing Ecological Index(kRSEI)using Moderate Resolution Imaging Spectroradiometer(MODIS)products on the Google Earth Engine(GEE)platform to analyze the spatiotemporal patterns and trends in ecological environmental quality(EEQ)across the LP from 2000 to 2022 and project future trajectories.Then,we applied partial correlation analysis and multivariate regression residual analysis to further quantify the relative contributions of climate change and human activities to EEQ.During the study period,the kRSEI values exhibited significant spatial heterogeneity,with a stepwise degradation pattern in the southeast to northwest across the LP.The maximum(0.51)and minimum(0.46)values of the kRSEI were observed in 2007 and 2021,respectively.Trend analyses revealed a decline in EEQ across the LP.Hurst exponent analysis predicted a trend of weak anti-persistent development in most of the plateau areas in the future.A positive correlation was identified between kRSEI and precipitation,particularly in the central and western regions;although,improvements were limited by a precipitation threshold of 837.66 mm/a.A moderate increase in temperature was shown to potentially benefit the ecological environment within a certain range;however,temperature of-1.00°C-7.95°C often had a negative impact on the ecosystem.Climate change and human activities jointly influenced 65.78%of LP area on EEQ,primarily having a negative impact.In terms of contribution,human activities played a dominant role in driving changes in EEQ across the plateau.These findings provide crucial insights for accurately assessing the ecological state of the LP and suggest the design of future restoration strategies.展开更多
Understanding the ecological evolution is of great significance in addressing the impacts of climate change and human activities.However,the ecological evolution and its drivers remain inadequately explored in arid an...Understanding the ecological evolution is of great significance in addressing the impacts of climate change and human activities.However,the ecological evolution and its drivers remain inadequately explored in arid and semi-arid areas.This study took the Helan Mountain,a typical arid and semi-arid area in China,as the study area.By adopting an Enhanced Remote Sensing Ecological Index(ERSEI)that integrates the habitat quality(HQ)index with the Remote Sensing Ecological Index(RSEI),we quantified the ecological environment quality of the Helan Mountain during 2010-2022 and analyzed the driving factors behind the changes.Principal Component Analysis(PCA)was used to validate the composite ERSEI,enabling the extraction of key features and the reduction of redundant information.The results showed that the contributions of first principal component(PC1)for ERSEI and RSEI were 80.23%and 78.72%,respectively,indicating that the ERSEI can provide higher precision and more details than the RSEI in assessing ecological environment quality.Temporally,the ERSEI in the Helan Mountain exhibited an initial decline followed by an increase from 2010 to 2022,with the average value of ERSEI ranging between 0.298 and 0.346.Spatially,the ERSEI showed a trend of being higher in the southwest and lower in the northeast,with high-quality ecological environments mainly concentrated in the western foothills at higher altitudes.The centroid of ERSEI shifted northeastward toward Helan County from 2010 to 2022.Temperature and digital elevation model(DEM)emerged as the primary drivers of ERSEI changes.This study highlights the necessity of using comprehensive monitoring tools to guide policy-making and conservation strategies,ensuring the resilience of fragile ecosystems in the face of ongoing climatic and anthropogenic pressures.The findings offer valuable insights for the sustainable management and conservation in arid and semi-arid ecosystems.展开更多
Slope climbing of urban expansion(SCE),as a form of urbanization,has increasingly significant impacts on urban development.Unsustainable slope climbing of urban expansion can harm the natural environment,thereby affec...Slope climbing of urban expansion(SCE),as a form of urbanization,has increasingly significant impacts on urban development.Unsustainable slope climbing of urban expansion can harm the natural environment,thereby affecting human production and living conditions.Using a coupled coordination model and the geographically weighted regression(GTWR)model,leveraging night light remote sensing data and ecological environment quality index model,this study investigated the coupling relationship between urban expansion and ecological environment quality and its influencing factors in the Yangtze River Economic Belt of China from 2000 to 2020.The results indicate that from 2000 to 2020,the intensity of urban slope climbing in the Yangtze River Economic Belt showed a fluctuating upward trend,with the slope climbing intensity being most significant in Chongqing Municipality and Kunming of Yunnan Province.Overall,the ecological environment quality exhibited an upward trend,with over 80%of the study area maintaining stable or improved ecological quality.There is a certain spatial correspondence between ecological environment quality and urban slope climbing.Although these two aspects of development demonstrate a high degree of coordination,fluctuations still occur during the development process.Further research on the coupling coordination relationship between the two revealed that population density has a negative impact on coupling coordination in the eastern region,and technology expenditure in eastern coastal cities has shown a negative trend over time.To ensure the continued increase in the proportion of highly coordinated areas in the future,eastern coastal cities in the study region could prioritize ecological civilization construction,strengthen urban construction and development planning,adjust influencing factors,and ensure the coordinated development of urban growth with ecological environment quality.展开更多
[Objective] The aim was to evaluate heavy metal environmental quality of irrigation water in vegetable farmlands of Shandong Province. [Method] Heavy metal contents including Hg,Cd,As,Cr (+6),Pb,Cu and Zn in irrigatio...[Objective] The aim was to evaluate heavy metal environmental quality of irrigation water in vegetable farmlands of Shandong Province. [Method] Heavy metal contents including Hg,Cd,As,Cr (+6),Pb,Cu and Zn in irrigation water of main vegetable farmlands of Shandong Province were investigated by randomly sampling,and the environmental quality conditions of these heavy metals were evaluated by methods of single quality index and complex quality index. [Result] The results showed that the average contents of heavy metals in irrigation water of Shouguang,Laiyang,Jinxiang and Zhangqiu were all far lower than the limit values prescribed by 'Farmland Environmental Quality Evaluation Standards for Edible Agricultural Products' (HJ332-2006),and no heavy metal was found beyond the limit value in every sample. The single quality indices of the 7 elements in the studied 4 places were all lower than 0.5. The comprehensive quality index of the seven elements was 0.317 8 in Shouguang,0.320 4 in Laiyang,0.232 6 in Jinxiang,and 0.260 7 in Zhangqiu. The environmental quality of irrigation water in the studied four places were all set at the first class. [Conclusion] The environmental quality of irrigation water in the 4 places belonged to clean level and were fit for the plantation of no pollution vegetables.展开更多
ln order to appraise scientifical y the heavy metal contamination in waste-land of coalmine tailing in Mingshan of Guangdong, the 5 soil samples in wasteland of coalmine tailing were col ected in November 2010 to Marc...ln order to appraise scientifical y the heavy metal contamination in waste-land of coalmine tailing in Mingshan of Guangdong, the 5 soil samples in wasteland of coalmine tailing were col ected in November 2010 to March 2011. The 7 heavy metals content in the contaminated soil was measured by atomic absorption spec-trophotometry. The results showed the pH of the wasteland soil ranged from 2.87 to 6.16, and the soil was relatively infertile. The soil was mainly pol uted by Cd and Mn. The Cd content in wasteland soil ranged from 0.759 mg/kg to 3.109 mg/kg with an average content of 2.052 mg/kg, which was much higher than the standard content. The Mn content ranged from 387.057 to 488.660 mg/kg with an average content of 421.215 mg/kg, which was much higher than the standard content. The Nemerow integrated pol ution indexes showed the sample 1, sample 4 and sample 5 were of heavy pol ution, and sample 2 and sample 3 were of moderate pol ution.展开更多
There is a need to formulate water environment standards（WESs） from the current water quality criteria（WQC） in China.To this end,we briefly summarize typical mechanisms applied in several countries with longer his...There is a need to formulate water environment standards（WESs） from the current water quality criteria（WQC） in China.To this end,we briefly summarize typical mechanisms applied in several countries with longer histories of developing WESs,and three limitations to formulating WESs in China were identified.After analyzing the feasibility factors including economic development,scientific support capability and environmental policies,we realized that China is still not ready for a complete change from its current nation-wide unified WES system to a local-standard-based system.Thus,we proposed a framework for transformation from WQC to WESs in China.The framework consists of three parts,including responsibilities,processes and policies.The responsibilities include research authorization,development of guidelines,and collection of information,at both national and local levels;the processes include four steps and an impact factor system to establish water quality standards;and the policies include seven specific proposals.展开更多
[Objective] The aim was to explore evaluated precision on quality of soil environment polluted with zinc in agricultural production areas and to provide references for verification of production area.[Method] In Shula...[Objective] The aim was to explore evaluated precision on quality of soil environment polluted with zinc in agricultural production areas and to provide references for verification of production area.[Method] In Shulan City in Jilin Province,soils were sampled and analyzed in a laboratory using single-factor pollution index and GIS based spatial interpolation.The quality of environment polluted with zinc was assessed and related methods were compared according to Environment Quality Standard of Green Food Production Area.[Result] Spatial interpolation of zinc in soils based on GIS proved more precise than traditional methods;cokriging method with co-factors was higher in precision than common cokriging;cokriging method with zinc and organic matter was higher in precision than cokriging with zinc alone.[Conclusion] Quality assessment on environment polluted with zinc based on GIS interpolation is more scientific and reasonable than traditional methods.展开更多
In this paper, traffic environment quality assessment is achieved by applying fuzzy mathematics methods. Set up an assessment system, determine assessment criterion, formulate membership function, make program designs...In this paper, traffic environment quality assessment is achieved by applying fuzzy mathematics methods. Set up an assessment system, determine assessment criterion, formulate membership function, make program designs and conduct example analysis. The evaluation result is consistent with the real case. So that the method of the fuzzy evaluation is a good one for the environment quality assessment.展开更多
Heavy metal contents in the soils in the Baoshan District of Shanghai were monitored to evaluate the risk of soil environmental quality degradation due to rapid urbanization and to reveal the ways of heavy metal accum...Heavy metal contents in the soils in the Baoshan District of Shanghai were monitored to evaluate the risk of soil environmental quality degradation due to rapid urbanization and to reveal the ways of heavy metal accumulation in soil during rapid urban sprawl. It was found that the soils in this district were commonly contaminated by Pb, Zn and Cd. Evaluated with a geo-accumulation index (Igeo), the rate of Pb contamination in soils was 100% with 59% of these graded as moderate-severe or severe; Zn contamination reached 59% with 6% graded as moderate-severe or severe; and Cd contamination was over 50%, with one site graded as moderate-severe and another severe-extremely severe. Metal contamination of soils around the Shanghai metropolis was mainly attributed to traffic, industrial production, wastewater irrigation and improper disposal of solid wastes. Because of continuing urbanization, the cultivated land around the metropolis should be comprehensively planned and carefully managed. Also the soil environmental quality of vegetable production bases in this area should be monitored regularly, with vegetables to be grown selected according to the degrees and types of soil contamination.展开更多
Heavy metal concentrations in agricultural soils of Zhejiang Province were monitored to indicate the status of heavy metal contamination and assess environmental quality of agricultural soils. A total of 908 soil samp...Heavy metal concentrations in agricultural soils of Zhejiang Province were monitored to indicate the status of heavy metal contamination and assess environmental quality of agricultural soils. A total of 908 soil samples were collected from 38 counties in Zbejiang Province and eight heavy metal （Cd, Cr, Pb, Hg, Cu, Zn, Ni and As） concentrations had been evaluated in agricultural soil. It was found 775 samples were unpolluted and 133 samples were slightly polluted and more respectively, that is approximately 14.65% agricultural soil samples had the heavy metal concentration above the threshold level in this province by means of Nemerow＇s synthetical pollution index method according to the second grade of Standards for Soil Environmental Quality of China （GB15618- 1995）. Contamination of Cd was the highest, followed by Ni, As and Zn were lower correspondingly. Moreover, Inverse Distance Weighted （IDW） interpolation method was used to make an assessment map of soil environmental quality based on the Nemerow＇s pollution index and the soil environmental quality was categorized into five grades. Moreover, ten indices were calculated as input parameters for principal component analysis （PCA） and the principal components （PCs） were created to compare environmental quality of different soils and regions. The results revealed that environmental quality of tea soils was better than that of paddy soils, vegetable soils and fruit soils. This study indicated that GIS combined with multivariate statistical approaches proved to be effective and powerful tool in the mapping of soil contamination distribution and the assessment of soil environmental quality on provincial scale, which is beneficial to environmental protection and management decision-making by local government.展开更多
The litterbag method was used to study the decomposition of wetland plant root in three wetlands along a water level gradient in the Sanjiang Plain,Northeast China.These wetlands are Calamagrostis angustifolia(C.aa),C...The litterbag method was used to study the decomposition of wetland plant root in three wetlands along a water level gradient in the Sanjiang Plain,Northeast China.These wetlands are Calamagrostis angustifolia(C.aa),Carex meyeriana(C.ma)and Carex lasiocarpa (C.la).The objective of our study is to evaluate the influence of environment and substrate quality on decomposition rates in the three wetlands.Calico material was used as a standard substrate to evaluate environmental influences.Roots native to each we...展开更多
Intertidal zone is a significant wetland between land and ocean. It plays an important rolein maintaining local ecological balance. Both Mai Po and Futian intertidal mudflats are located in Shenzhen Bay and are import...Intertidal zone is a significant wetland between land and ocean. It plays an important rolein maintaining local ecological balance. Both Mai Po and Futian intertidal mudflats are located in Shenzhen Bay and are important 'refueling' point along the East Asian/Australian flyway of migratory birds. The environmental quality of Mai Po and Futian mudflats have aroused great concern due to rapid economic developments in Hong Kong and Shenzhen in recent decades. Macroinfauna of Mai Po and Futian mudflats was investigated in December 2000 and the faunal data were used to assess their environmental quality. Two other mudflats, namely Ma Wan Typhoon Shelter (a more disturbed area) and Luk Keng intertidal mudflat (a place with relatively less human disturbance), were also sampled for macroinfauna and used as reference mudflats. Shannon - Weaver species diversity index (Isd), biotic coefficient (Cb) and macrofaunal pollution index (Imp) of the macrofauna community on four intertidal mudflats were used to determine their environmental quality. The results showed that Luk Keng intertidal mudflat was unpolluted, Mai Po and Futian mudflats were slightly polluted, and Ma Wan was moderately polluted. The pollution in Ma Wan Typhoon Shelter mainly came from various types of rubbish and fishing boats that disturbed the sediment, while pollution sources in Mai Po and Futian mudflats were discharges of industrial water, municipal sewage and from nearby rivers.展开更多
Problems in water-land resources and environmental quality increase with the fast economic development in the coastal region of southeastern China. This region has the highest density in population, industry and towns...Problems in water-land resources and environmental quality increase with the fast economic development in the coastal region of southeastern China. This region has the highest density in population, industry and towns in China, and the large export-oriented economy makes itself a strategic importance while China enters into international markets. The problems facing to this region include arable land reduction, land degradation aggravation, high percentage of built-up land with high rate of expansion, expanded non-point pollution, deteriorated water quality, decreasing biodiversity, destroyed ecosystems, severe air pollution, frequently occurred acid rain, and multi-pollutants. The important research fields in the near future should include a) influence of high-intensity exploitation of resources on changes of environment quality and its feedback; b) interface processes, key mechanisms and adjustment principles for degradation of water-, land-, and air-resources and environmental quality; c) evolvement processes and nurturing theory of biodiversity and ecological resources; and d) spatio-temporal variation and human-induced effects on regional resources and environment quality. Strategies for sustainable development in the region are as follows: a) controlling to ensure basic cultivated land area; b) enforcing remediation of polluted water environment, and controlling non-point pollution; c) strengthening ecological construction and ecological security; and d) controlling multi-pollution and preventing trace toxic pollutants.展开更多
The relative importance of each pollution factor in analytical hierarchy process (AHP) method comes from pooling expert opinions in general. Because expert opinions are based on information and judgment criteria, dete...The relative importance of each pollution factor in analytical hierarchy process (AHP) method comes from pooling expert opinions in general. Because expert opinions are based on information and judgment criteria, determining their weight may lead to uncertainty.. Therefore, an improved AHP method had been developed. The process of the improved AHP method involved four key procedures. The weights of pollution factors were completely related to the objective monitoring data through the standardization of these procedures. The environmental comprehensive quality of water and sediment of Xuanwu Lake, Nanjing, China had been evaluated. The environmental quality comprehensive indices (EQCI) of the water in 1991-1995 and 1996-2000 were 3.32 and 1.85, respectively, indicating that the water quality improved. The EQCI of the sediment in 1995 and 2000 indicates that the sediment contamination decreased from 1995 to 2000. Such results agreed with the fact that the lake had been under comprehensive control. However, with the classical AHP method, the EQCI of the sediment in the northwestern part of the lake may have indicated that sediment contamination increased from 1995 to 2000. The discrepancy may have resulted from the judgment difference of the experts. The improved AHP method can avoid arbitrariness of subjective judgment and can reflect the real influential factors of environment pollution in different periods or regions.展开更多
Objective To evaluate the environmental quality of Guiyu, Guangdong impacted by the electronic waste recycling industry. Methods The surface water, ground water and sediment samples taken separately from two sites tha...Objective To evaluate the environmental quality of Guiyu, Guangdong impacted by the electronic waste recycling industry. Methods The surface water, ground water and sediment samples taken separately from two sites that recycle E-wastes and other rubbish relevant to the E-waste recycling, and an agricultural area, were analyzed, and the data were used to evaluate the impact of E-waste recycling on the environmental quality of Guiyu based on environmental quality standards in China. Results The concentrations of lead and iron in the surface water samples significantly different in the three locations. The maximum value of lead in the first site was 8 times higher than the threshold of environmental quality standards for surface water. The concentration of iron in polluted sample was 22 times that of the background sample. Manganese and iron also showed a significant difference in ground water samples between the three sites. The amount of iron was 22 times that of the threshold of the quality standard for ground water, and 120 times that of the background sample. Moreover, the results of all the eight heavy metals showed significant differences among the sediment samples. The concentrations of copper, cadmium, nickel, and lead in the polluted samples were above the median benchmarks of National Oceanic and Atmospheric Administration （NOAA）. The copper concentration of 2670 mg/kg was 10 times that of the median benchmark. Conclusion E-waste recycling has led to the severe pollution Guiyu.展开更多
Based on the decomposition model of environmental quality and univariate regression model,the relationships of industrial wastewater drainage with economic scale,economic structure,and technological level in Anshan,a ...Based on the decomposition model of environmental quality and univariate regression model,the relationships of industrial wastewater drainage with economic scale,economic structure,and technological level in Anshan,a mining city in Northeast China,were studied. The results showed that,due to scale effect,the drainage of three important industrial wastewater pollutants(COD,NH3-N and petroleum) increased 8505t,671t and 384t,respectively,and due to structure effect,those pollutants drainage increased 3996t,174t and 120t from 2001 to 2006. While due to technological effect,the drainage of COD,NH3-N and petroleum reduced 4452t,458t and 331t,and due to cross effect,those pollutants drainage reduced 7270t,575t and 476t simultaneously. Meantime,the relationships between household consumption structure and domestic sewage discharge were analyzed,and domestic sewage discharges in different income levels were also compared. The results showed that,the domestic sewage discharges would increase 376t with 1000 yuan(RMB) increased in the traffic and communication consumption,and they would be 344t,219t,428t,1873t,respectively,in housing consumption,food consumption,medical consumption,miscellaneous commodity consumption. The proportion of domestic sewage discharge increased for high income residents significantly,but reduced for lower income residents. The industrial wastewater pollutants drainage tends to be reduced by technical progress,while domestic sewage discharge will be a more important factor for urban water environment quality.展开更多
Urban heat environmental quality (UHEQ) is affected by the interacting of weather condition and underlying surface framework of urban area. In the last two decades, many researchers from domestic and overseas have stu...Urban heat environmental quality (UHEQ) is affected by the interacting of weather condition and underlying surface framework of urban area. In the last two decades, many researchers from domestic and overseas have studied many problems at the aspect of urban heat environment such as urban heat islands, urban air temperature and their relation with urban land cover, city population, air pollution etc. In the recent years, Hangzhou, acting as a center city of Zhejiang Province in China, its urbanization quantum and quantity have both changed greatly, in particular, representing as business affairs building, resident real property and all kinds of specialty market having arisen in built-up zone. Based on Landsat TM images data in 1991 and 1999, urban underlying surface temperature value and Normalized Difference Vegetation Index (NDVI) were calculated using image interpreting and supervised classification technique by remote sensing software ERDAS image 8.4. The relation model between urban underlying surface temperature (UUST) and urban air temperature was setup according to the certain correlation pattern. Reference to the relational standard of assessing human comfort and other meteorology data of Hangzhou City in summer, the spatial distribution characteristic and the spatial variation degree of human comfort of heat environmental quality are estimated and mapped on a middle scale, that is, in six districts of Hangzhou City . Then the paper reveals the main characteristic of spatial variation from 1991 to 1999. Lastly, the change mechanism is analyzed and discussed from the viewpoint of city planning, construction and environmental protection.展开更多
Protecting the ecological security of the Qinghai-Tibet Plateau(QTP)is of great importance for global ecology and climate.Over the past few decades,climate extremes have posed a significant challenge to the ecological...Protecting the ecological security of the Qinghai-Tibet Plateau(QTP)is of great importance for global ecology and climate.Over the past few decades,climate extremes have posed a significant challenge to the ecological environment of the QTP.However,there are few studies that explored the effects of climate extremes on ecological environment quality of the QTP,and few researchers have made quantitative analysis.Hereby,this paper proposed the Ecological Environmental Quality Index(EEQI)for analyzing the spatial and temporal variation of ecological environment quality on the QTP from 2000 to 2020,and explored the effects of climate extremes on EEQI based on Geographically and Temporally Weighted Regression(GTWR)model.The results showed that the ecological environment quality in QTP was poor in the west,but good in the east.Between 2000 and 2020,the area of EEQI variation was large(34.61%of the total area),but the intensity of EEQI variation was relatively low and occurred mainly by a slightly increasing level(EEQI change range of 0.05-0.1).The overall ecological environment quality of the QTP exhibited spatial and temporal fluctuations,which may be attributed to climate extremes.Significant spatial heterogeneity was observed in the effects of the climate extremes on ecological environment quality.Specifically,the effects of daily temperature range(DTR),number of frost days(FD0),maximum 5-day precipitation(RX5day),and moderate precipitation days(R10)on ecological environment quality were positive in most regions.Furthermore,there were significant temporal differences in the effects of consecutive dry days(CDD),consecutive wet days(CWD),R10,and FD0 on ecological environment quality.These differences may be attributed to variances in ecological environment quality,climate extremes,and vegetation types across different regions.In conclusion,the impact of climate extremes on ecological environment quality exhibits complex patterns.These findings will assist managers in identifying changes in the ecological environment quality of the QTP and addressing the effects of climate extremes.展开更多
基金National Natural Science Foundation of China,No.41971268。
文摘Regular quantitative assessments of regional ecological environment quality(EEQ)and driving force analyses are highly important for environmental protection and sustainable development.Northern China is a typical climate-sensitive and ecologically vulnerable area,however,the changes in EEQ in this region and their underlying causes remain unclear.Traditional evaluations of EEQ rely primarily on the remote sensing ecological index(RSEI),which lacks assessments of indicators such as greenness(NDVI),humidity(WET),heat(LST),and dryness(NDBSI).To address these issues,this study employs the principal component analysis method and the Google Earth Engine to construct an RSEI suitable for long-term and large-scale applications and analyzes the spatio-temporal variations in the RSEI,NDVI,WET,NDBSI,and LST.Additionally,geographical detectors are utilized to analyze the driving factors affecting EEQ.The results indicate the following.(1)The RSEI shows a fluctuating upward trend,with an average value of 0.4566,indicating a gradual improvement in EEQ.The EEQ exhibited significant spatial heterogeneity,with a pattern of lower values in the west and higher values in the east.(2)The NDVI and WET exhibit fluctuating increasing trends,indicating improvements in both indices.The NDBSI shows a fluctuating decreasing trend,whereas the LST presents a fluctuating increasing trend,suggesting an improvement in the NDBSI and a slight deterioration in the LST.NDVI and WET demonstrate a spatial pattern characterized by low values in the west and high values in the east.NDBSI and LST demonstrate a spatial pattern characterized by low values in the east and high values in the west.(3)Land use types and precipitation are the primary driving factors influencing the spatial differentiation of the EEQ.The explanatory power of these driving factors significantly increases under their interactions,particularly the interaction between land use types and other driving factors.This study fills the gap in existing EEQ evaluations that analyze only the RSEI without considering the NDVI,WET,NDBSI,and LST.The findings provide new insights for EEQ assessments and serve as a scientific reference for environmental protection and sustainable development.
文摘To conduct a comprehensive analysis of the current status of water environment quality in Yilong Lake,a systematic study was undertaken to characterize the evolution of water quality.This study utilized monthly data on water quality indicators collected from three monitoring sections of Yilong Lake between 2016 and 2023,employing the Mann-Kendall trend test and ArcGIS spatial interpolation technique.The results indicated that the five-day biochemical oxygen demand(BOD5),total nitrogen(TN),and chlorophyll a(Chla)exhibited an overall increasing trend,whereas other indicators demonstrated a decreasing trend.The permanganate index(PI),chemical oxygen demand(COD),TN,and Chla were observed in the following order:east of the lake>middle of the lake>west of the lake.In contrast,the BOD5 and total phosphorus(TP)were ranked as west of the lake>east of the lake>middle of the lake.Additionally,ammonia nitrogen(NH3-N)was found to be in the order of east of the lake>west of the lake>middle of the lake,while transparency was ranked as west of the lake>middle of the lake>east of the lake.Urban domestic sewage,effluent from industrial parks,domestic waste generated by rural residents’production and daily activities,agricultural waste,wastewater from decentralized farming,domestic sewage,and point source discharges from the soybean processing industry are the primary contributors to the exceedance of water quality standards.The enhancement of a precise pollution control system,along with the regulation of pollution sources and the interception of pollutants,can significantly diminish the pollution load entering the lake.This approach is essential for the protection and restoration of river and lake ecosystems,thereby facilitating the gradual recovery of their ecological functions.Additionally,the implementation of ecological water replenishment and the recycling of water resources can improve the capacity of the water environment.Furthermore,bolstering scientific and technological support,as well as comprehensive supervision and assurance measures,is crucial to ensuring that water quality remains stable and adheres to established standards.
基金funded by the National Natural Science Foundation of China(42361017)the Gansu Provincial Science and Technology Program-Special Program for Key Research and Development(R&D)on Ecological Civilization Construction in Gansu Province(24YFFA050)the Gansu Agricultural University-Gansu Provincial Academy of Natural Resources Planning Joint Graduate Training Base Project(GAU2024-003)。
文摘The Loess Plateau(LP),one of the most ecologically fragile regions in China,is affected by severe soil erosion and environmental degradation.Despite large-scale ecological restoration efforts made by Chinese government in recent years,the region continues to face significant ecological challenges due to the combined impact of climate change and human activities.In this context,we developed a kernal Remote Sensing Ecological Index(kRSEI)using Moderate Resolution Imaging Spectroradiometer(MODIS)products on the Google Earth Engine(GEE)platform to analyze the spatiotemporal patterns and trends in ecological environmental quality(EEQ)across the LP from 2000 to 2022 and project future trajectories.Then,we applied partial correlation analysis and multivariate regression residual analysis to further quantify the relative contributions of climate change and human activities to EEQ.During the study period,the kRSEI values exhibited significant spatial heterogeneity,with a stepwise degradation pattern in the southeast to northwest across the LP.The maximum(0.51)and minimum(0.46)values of the kRSEI were observed in 2007 and 2021,respectively.Trend analyses revealed a decline in EEQ across the LP.Hurst exponent analysis predicted a trend of weak anti-persistent development in most of the plateau areas in the future.A positive correlation was identified between kRSEI and precipitation,particularly in the central and western regions;although,improvements were limited by a precipitation threshold of 837.66 mm/a.A moderate increase in temperature was shown to potentially benefit the ecological environment within a certain range;however,temperature of-1.00°C-7.95°C often had a negative impact on the ecosystem.Climate change and human activities jointly influenced 65.78%of LP area on EEQ,primarily having a negative impact.In terms of contribution,human activities played a dominant role in driving changes in EEQ across the plateau.These findings provide crucial insights for accurately assessing the ecological state of the LP and suggest the design of future restoration strategies.
基金funded by the Fujian Province's Foreign Cooperation Project in 2023(2023I0047)the Fujian Provincial Natural Science Foundation Project(2023J011432,2024J011195)+3 种基金the Ministry of Education's Supply-demand Docking Employment and Education Project(2024011223947)the Open Project Fund of Hunan Provincial Key Laboratory for Remote Sensing Monitoring of Ecological Environment in Dongting Lake Area(DTH Key Lab.2024-04,2022-04)the Fujian Provincial Natural Science Foundation Guiding Project(2024Y0057)the Fujian Province Social Science Plan Project(FJ2024BF071).
文摘Understanding the ecological evolution is of great significance in addressing the impacts of climate change and human activities.However,the ecological evolution and its drivers remain inadequately explored in arid and semi-arid areas.This study took the Helan Mountain,a typical arid and semi-arid area in China,as the study area.By adopting an Enhanced Remote Sensing Ecological Index(ERSEI)that integrates the habitat quality(HQ)index with the Remote Sensing Ecological Index(RSEI),we quantified the ecological environment quality of the Helan Mountain during 2010-2022 and analyzed the driving factors behind the changes.Principal Component Analysis(PCA)was used to validate the composite ERSEI,enabling the extraction of key features and the reduction of redundant information.The results showed that the contributions of first principal component(PC1)for ERSEI and RSEI were 80.23%and 78.72%,respectively,indicating that the ERSEI can provide higher precision and more details than the RSEI in assessing ecological environment quality.Temporally,the ERSEI in the Helan Mountain exhibited an initial decline followed by an increase from 2010 to 2022,with the average value of ERSEI ranging between 0.298 and 0.346.Spatially,the ERSEI showed a trend of being higher in the southwest and lower in the northeast,with high-quality ecological environments mainly concentrated in the western foothills at higher altitudes.The centroid of ERSEI shifted northeastward toward Helan County from 2010 to 2022.Temperature and digital elevation model(DEM)emerged as the primary drivers of ERSEI changes.This study highlights the necessity of using comprehensive monitoring tools to guide policy-making and conservation strategies,ensuring the resilience of fragile ecosystems in the face of ongoing climatic and anthropogenic pressures.The findings offer valuable insights for the sustainable management and conservation in arid and semi-arid ecosystems.
基金Under the auspices of National Natural Science Foundation of China(No.42371191)Science and Technology Planning of NIGLAS(No.NIGLAS2022GS06,2022NIGLAS-CJH04)。
文摘Slope climbing of urban expansion(SCE),as a form of urbanization,has increasingly significant impacts on urban development.Unsustainable slope climbing of urban expansion can harm the natural environment,thereby affecting human production and living conditions.Using a coupled coordination model and the geographically weighted regression(GTWR)model,leveraging night light remote sensing data and ecological environment quality index model,this study investigated the coupling relationship between urban expansion and ecological environment quality and its influencing factors in the Yangtze River Economic Belt of China from 2000 to 2020.The results indicate that from 2000 to 2020,the intensity of urban slope climbing in the Yangtze River Economic Belt showed a fluctuating upward trend,with the slope climbing intensity being most significant in Chongqing Municipality and Kunming of Yunnan Province.Overall,the ecological environment quality exhibited an upward trend,with over 80%of the study area maintaining stable or improved ecological quality.There is a certain spatial correspondence between ecological environment quality and urban slope climbing.Although these two aspects of development demonstrate a high degree of coordination,fluctuations still occur during the development process.Further research on the coupling coordination relationship between the two revealed that population density has a negative impact on coupling coordination in the eastern region,and technology expenditure in eastern coastal cities has shown a negative trend over time.To ensure the continued increase in the proportion of highly coordinated areas in the future,eastern coastal cities in the study region could prioritize ecological civilization construction,strengthen urban construction and development planning,adjust influencing factors,and ensure the coordinated development of urban growth with ecological environment quality.
基金Supported by National Science and Technology Project of "the Eleventh Five-year Plan" of China (2006BAD17B07)Doctoral Fund of Shandong Academy of Agricultural Sciences (2006YBS015)~~
文摘[Objective] The aim was to evaluate heavy metal environmental quality of irrigation water in vegetable farmlands of Shandong Province. [Method] Heavy metal contents including Hg,Cd,As,Cr (+6),Pb,Cu and Zn in irrigation water of main vegetable farmlands of Shandong Province were investigated by randomly sampling,and the environmental quality conditions of these heavy metals were evaluated by methods of single quality index and complex quality index. [Result] The results showed that the average contents of heavy metals in irrigation water of Shouguang,Laiyang,Jinxiang and Zhangqiu were all far lower than the limit values prescribed by 'Farmland Environmental Quality Evaluation Standards for Edible Agricultural Products' (HJ332-2006),and no heavy metal was found beyond the limit value in every sample. The single quality indices of the 7 elements in the studied 4 places were all lower than 0.5. The comprehensive quality index of the seven elements was 0.317 8 in Shouguang,0.320 4 in Laiyang,0.232 6 in Jinxiang,and 0.260 7 in Zhangqiu. The environmental quality of irrigation water in the studied four places were all set at the first class. [Conclusion] The environmental quality of irrigation water in the 4 places belonged to clean level and were fit for the plantation of no pollution vegetables.
基金Supported by Guangdong Science and Technology Plan Project(2010B0318000112012A030700006)~~
文摘ln order to appraise scientifical y the heavy metal contamination in waste-land of coalmine tailing in Mingshan of Guangdong, the 5 soil samples in wasteland of coalmine tailing were col ected in November 2010 to March 2011. The 7 heavy metals content in the contaminated soil was measured by atomic absorption spec-trophotometry. The results showed the pH of the wasteland soil ranged from 2.87 to 6.16, and the soil was relatively infertile. The soil was mainly pol uted by Cd and Mn. The Cd content in wasteland soil ranged from 0.759 mg/kg to 3.109 mg/kg with an average content of 2.052 mg/kg, which was much higher than the standard content. The Mn content ranged from 387.057 to 488.660 mg/kg with an average content of 421.215 mg/kg, which was much higher than the standard content. The Nemerow integrated pol ution indexes showed the sample 1, sample 4 and sample 5 were of heavy pol ution, and sample 2 and sample 3 were of moderate pol ution.
基金supported by the National Water Pollution Control and Treatment Science and Technology Major Project(No.2015ZX07203-005)the National Natural Science Foundation of China(No.41571478)
文摘There is a need to formulate water environment standards（WESs） from the current water quality criteria（WQC） in China.To this end,we briefly summarize typical mechanisms applied in several countries with longer histories of developing WESs,and three limitations to formulating WESs in China were identified.After analyzing the feasibility factors including economic development,scientific support capability and environmental policies,we realized that China is still not ready for a complete change from its current nation-wide unified WES system to a local-standard-based system.Thus,we proposed a framework for transformation from WQC to WESs in China.The framework consists of three parts,including responsibilities,processes and policies.The responsibilities include research authorization,development of guidelines,and collection of information,at both national and local levels;the processes include four steps and an impact factor system to establish water quality standards;and the policies include seven specific proposals.
基金Supported by National 973 Program(2010CB951500)National 863 Program(2006AA-120103)~~
文摘[Objective] The aim was to explore evaluated precision on quality of soil environment polluted with zinc in agricultural production areas and to provide references for verification of production area.[Method] In Shulan City in Jilin Province,soils were sampled and analyzed in a laboratory using single-factor pollution index and GIS based spatial interpolation.The quality of environment polluted with zinc was assessed and related methods were compared according to Environment Quality Standard of Green Food Production Area.[Result] Spatial interpolation of zinc in soils based on GIS proved more precise than traditional methods;cokriging method with co-factors was higher in precision than common cokriging;cokriging method with zinc and organic matter was higher in precision than cokriging with zinc alone.[Conclusion] Quality assessment on environment polluted with zinc based on GIS interpolation is more scientific and reasonable than traditional methods.
文摘In this paper, traffic environment quality assessment is achieved by applying fuzzy mathematics methods. Set up an assessment system, determine assessment criterion, formulate membership function, make program designs and conduct example analysis. The evaluation result is consistent with the real case. So that the method of the fuzzy evaluation is a good one for the environment quality assessment.
基金Project supported by the National Natural Science Foundation of China (Nos. 40235054, 40131020 and 40101013) and the Science Foundation of Shanghai Higher Schools for Young Teachers.
文摘Heavy metal contents in the soils in the Baoshan District of Shanghai were monitored to evaluate the risk of soil environmental quality degradation due to rapid urbanization and to reveal the ways of heavy metal accumulation in soil during rapid urban sprawl. It was found that the soils in this district were commonly contaminated by Pb, Zn and Cd. Evaluated with a geo-accumulation index (Igeo), the rate of Pb contamination in soils was 100% with 59% of these graded as moderate-severe or severe; Zn contamination reached 59% with 6% graded as moderate-severe or severe; and Cd contamination was over 50%, with one site graded as moderate-severe and another severe-extremely severe. Metal contamination of soils around the Shanghai metropolis was mainly attributed to traffic, industrial production, wastewater irrigation and improper disposal of solid wastes. Because of continuing urbanization, the cultivated land around the metropolis should be comprehensively planned and carefully managed. Also the soil environmental quality of vegetable production bases in this area should be monitored regularly, with vegetables to be grown selected according to the degrees and types of soil contamination.
基金Project supported by the National Natural Science Foundation of China (No. 40001008) the Science and Technology Project of Zhejiang Province (No. 2004C32066).
文摘Heavy metal concentrations in agricultural soils of Zhejiang Province were monitored to indicate the status of heavy metal contamination and assess environmental quality of agricultural soils. A total of 908 soil samples were collected from 38 counties in Zbejiang Province and eight heavy metal （Cd, Cr, Pb, Hg, Cu, Zn, Ni and As） concentrations had been evaluated in agricultural soil. It was found 775 samples were unpolluted and 133 samples were slightly polluted and more respectively, that is approximately 14.65% agricultural soil samples had the heavy metal concentration above the threshold level in this province by means of Nemerow＇s synthetical pollution index method according to the second grade of Standards for Soil Environmental Quality of China （GB15618- 1995）. Contamination of Cd was the highest, followed by Ni, As and Zn were lower correspondingly. Moreover, Inverse Distance Weighted （IDW） interpolation method was used to make an assessment map of soil environmental quality based on the Nemerow＇s pollution index and the soil environmental quality was categorized into five grades. Moreover, ten indices were calculated as input parameters for principal component analysis （PCA） and the principal components （PCs） were created to compare environmental quality of different soils and regions. The results revealed that environmental quality of tea soils was better than that of paddy soils, vegetable soils and fruit soils. This study indicated that GIS combined with multivariate statistical approaches proved to be effective and powerful tool in the mapping of soil contamination distribution and the assessment of soil environmental quality on provincial scale, which is beneficial to environmental protection and management decision-making by local government.
基金supported by the Key Knowledge In-novation Project of Chinese Academy of Science(No.KSCX2-YW-N-46-06).
文摘The litterbag method was used to study the decomposition of wetland plant root in three wetlands along a water level gradient in the Sanjiang Plain,Northeast China.These wetlands are Calamagrostis angustifolia(C.aa),Carex meyeriana(C.ma)and Carex lasiocarpa (C.la).The objective of our study is to evaluate the influence of environment and substrate quality on decomposition rates in the three wetlands.Calico material was used as a standard substrate to evaluate environmental influences.Roots native to each we...
文摘Intertidal zone is a significant wetland between land and ocean. It plays an important rolein maintaining local ecological balance. Both Mai Po and Futian intertidal mudflats are located in Shenzhen Bay and are important 'refueling' point along the East Asian/Australian flyway of migratory birds. The environmental quality of Mai Po and Futian mudflats have aroused great concern due to rapid economic developments in Hong Kong and Shenzhen in recent decades. Macroinfauna of Mai Po and Futian mudflats was investigated in December 2000 and the faunal data were used to assess their environmental quality. Two other mudflats, namely Ma Wan Typhoon Shelter (a more disturbed area) and Luk Keng intertidal mudflat (a place with relatively less human disturbance), were also sampled for macroinfauna and used as reference mudflats. Shannon - Weaver species diversity index (Isd), biotic coefficient (Cb) and macrofaunal pollution index (Imp) of the macrofauna community on four intertidal mudflats were used to determine their environmental quality. The results showed that Luk Keng intertidal mudflat was unpolluted, Mai Po and Futian mudflats were slightly polluted, and Ma Wan was moderately polluted. The pollution in Ma Wan Typhoon Shelter mainly came from various types of rubbish and fishing boats that disturbed the sediment, while pollution sources in Mai Po and Futian mudflats were discharges of industrial water, municipal sewage and from nearby rivers.
基金Project (No. G1999011801) supported by the National Key Basic Research Support Foundation (NKBRSF) of China.
文摘Problems in water-land resources and environmental quality increase with the fast economic development in the coastal region of southeastern China. This region has the highest density in population, industry and towns in China, and the large export-oriented economy makes itself a strategic importance while China enters into international markets. The problems facing to this region include arable land reduction, land degradation aggravation, high percentage of built-up land with high rate of expansion, expanded non-point pollution, deteriorated water quality, decreasing biodiversity, destroyed ecosystems, severe air pollution, frequently occurred acid rain, and multi-pollutants. The important research fields in the near future should include a) influence of high-intensity exploitation of resources on changes of environment quality and its feedback; b) interface processes, key mechanisms and adjustment principles for degradation of water-, land-, and air-resources and environmental quality; c) evolvement processes and nurturing theory of biodiversity and ecological resources; and d) spatio-temporal variation and human-induced effects on regional resources and environment quality. Strategies for sustainable development in the region are as follows: a) controlling to ensure basic cultivated land area; b) enforcing remediation of polluted water environment, and controlling non-point pollution; c) strengthening ecological construction and ecological security; and d) controlling multi-pollution and preventing trace toxic pollutants.
基金National Natural Science Foundation of China, No.40771186.
文摘The relative importance of each pollution factor in analytical hierarchy process (AHP) method comes from pooling expert opinions in general. Because expert opinions are based on information and judgment criteria, determining their weight may lead to uncertainty.. Therefore, an improved AHP method had been developed. The process of the improved AHP method involved four key procedures. The weights of pollution factors were completely related to the objective monitoring data through the standardization of these procedures. The environmental comprehensive quality of water and sediment of Xuanwu Lake, Nanjing, China had been evaluated. The environmental quality comprehensive indices (EQCI) of the water in 1991-1995 and 1996-2000 were 3.32 and 1.85, respectively, indicating that the water quality improved. The EQCI of the sediment in 1995 and 2000 indicates that the sediment contamination decreased from 1995 to 2000. Such results agreed with the fact that the lake had been under comprehensive control. However, with the classical AHP method, the EQCI of the sediment in the northwestern part of the lake may have indicated that sediment contamination increased from 1995 to 2000. The discrepancy may have resulted from the judgment difference of the experts. The improved AHP method can avoid arbitrariness of subjective judgment and can reflect the real influential factors of environment pollution in different periods or regions.
文摘Objective To evaluate the environmental quality of Guiyu, Guangdong impacted by the electronic waste recycling industry. Methods The surface water, ground water and sediment samples taken separately from two sites that recycle E-wastes and other rubbish relevant to the E-waste recycling, and an agricultural area, were analyzed, and the data were used to evaluate the impact of E-waste recycling on the environmental quality of Guiyu based on environmental quality standards in China. Results The concentrations of lead and iron in the surface water samples significantly different in the three locations. The maximum value of lead in the first site was 8 times higher than the threshold of environmental quality standards for surface water. The concentration of iron in polluted sample was 22 times that of the background sample. Manganese and iron also showed a significant difference in ground water samples between the three sites. The amount of iron was 22 times that of the threshold of the quality standard for ground water, and 120 times that of the background sample. Moreover, the results of all the eight heavy metals showed significant differences among the sediment samples. The concentrations of copper, cadmium, nickel, and lead in the polluted samples were above the median benchmarks of National Oceanic and Atmospheric Administration （NOAA）. The copper concentration of 2670 mg/kg was 10 times that of the median benchmark. Conclusion E-waste recycling has led to the severe pollution Guiyu.
基金Under the auspices of Major State Basic Research Development Program of China (No. 2004CB418507)
文摘Based on the decomposition model of environmental quality and univariate regression model,the relationships of industrial wastewater drainage with economic scale,economic structure,and technological level in Anshan,a mining city in Northeast China,were studied. The results showed that,due to scale effect,the drainage of three important industrial wastewater pollutants(COD,NH3-N and petroleum) increased 8505t,671t and 384t,respectively,and due to structure effect,those pollutants drainage increased 3996t,174t and 120t from 2001 to 2006. While due to technological effect,the drainage of COD,NH3-N and petroleum reduced 4452t,458t and 331t,and due to cross effect,those pollutants drainage reduced 7270t,575t and 476t simultaneously. Meantime,the relationships between household consumption structure and domestic sewage discharge were analyzed,and domestic sewage discharges in different income levels were also compared. The results showed that,the domestic sewage discharges would increase 376t with 1000 yuan(RMB) increased in the traffic and communication consumption,and they would be 344t,219t,428t,1873t,respectively,in housing consumption,food consumption,medical consumption,miscellaneous commodity consumption. The proportion of domestic sewage discharge increased for high income residents significantly,but reduced for lower income residents. The industrial wastewater pollutants drainage tends to be reduced by technical progress,while domestic sewage discharge will be a more important factor for urban water environment quality.
基金Under the auspices of the National Natural Science Foundation of China (No.40001008).
文摘Urban heat environmental quality (UHEQ) is affected by the interacting of weather condition and underlying surface framework of urban area. In the last two decades, many researchers from domestic and overseas have studied many problems at the aspect of urban heat environment such as urban heat islands, urban air temperature and their relation with urban land cover, city population, air pollution etc. In the recent years, Hangzhou, acting as a center city of Zhejiang Province in China, its urbanization quantum and quantity have both changed greatly, in particular, representing as business affairs building, resident real property and all kinds of specialty market having arisen in built-up zone. Based on Landsat TM images data in 1991 and 1999, urban underlying surface temperature value and Normalized Difference Vegetation Index (NDVI) were calculated using image interpreting and supervised classification technique by remote sensing software ERDAS image 8.4. The relation model between urban underlying surface temperature (UUST) and urban air temperature was setup according to the certain correlation pattern. Reference to the relational standard of assessing human comfort and other meteorology data of Hangzhou City in summer, the spatial distribution characteristic and the spatial variation degree of human comfort of heat environmental quality are estimated and mapped on a middle scale, that is, in six districts of Hangzhou City . Then the paper reveals the main characteristic of spatial variation from 1991 to 1999. Lastly, the change mechanism is analyzed and discussed from the viewpoint of city planning, construction and environmental protection.
基金funded by the key R&D project of the Sichuan Provincial Department of Science and Technology,“Research and Application of Key Technologies for Agricultural Drought Monitoring in Tibet Based on Multi-source Remote Sensing Data”(2021YFQ0042)Tibet Autonomous Region Science and Technology Support Plan Project“Construction and Demonstration Application of Ecological Environment Monitoring Technology System in Tibet Based on Three-Dimensional Remote Sensing Observation Network”(XZ201901-GA-07)。
文摘Protecting the ecological security of the Qinghai-Tibet Plateau(QTP)is of great importance for global ecology and climate.Over the past few decades,climate extremes have posed a significant challenge to the ecological environment of the QTP.However,there are few studies that explored the effects of climate extremes on ecological environment quality of the QTP,and few researchers have made quantitative analysis.Hereby,this paper proposed the Ecological Environmental Quality Index(EEQI)for analyzing the spatial and temporal variation of ecological environment quality on the QTP from 2000 to 2020,and explored the effects of climate extremes on EEQI based on Geographically and Temporally Weighted Regression(GTWR)model.The results showed that the ecological environment quality in QTP was poor in the west,but good in the east.Between 2000 and 2020,the area of EEQI variation was large(34.61%of the total area),but the intensity of EEQI variation was relatively low and occurred mainly by a slightly increasing level(EEQI change range of 0.05-0.1).The overall ecological environment quality of the QTP exhibited spatial and temporal fluctuations,which may be attributed to climate extremes.Significant spatial heterogeneity was observed in the effects of the climate extremes on ecological environment quality.Specifically,the effects of daily temperature range(DTR),number of frost days(FD0),maximum 5-day precipitation(RX5day),and moderate precipitation days(R10)on ecological environment quality were positive in most regions.Furthermore,there were significant temporal differences in the effects of consecutive dry days(CDD),consecutive wet days(CWD),R10,and FD0 on ecological environment quality.These differences may be attributed to variances in ecological environment quality,climate extremes,and vegetation types across different regions.In conclusion,the impact of climate extremes on ecological environment quality exhibits complex patterns.These findings will assist managers in identifying changes in the ecological environment quality of the QTP and addressing the effects of climate extremes.
