The water conservation(WC) function of ecosystems is related to regional ecological security and the sustainable development of water resources, and the assessment of WC and its influencing factors is crucial for ecol...The water conservation(WC) function of ecosystems is related to regional ecological security and the sustainable development of water resources, and the assessment of WC and its influencing factors is crucial for ecological and water resource management.The Tumen River Basin(TRB) is located in the core of the Northeast Asian ecological network and has been experiencing severe ecological crises and water shortages in recent years due to climate change and human activities. However, these crises have not been fully revealed to the extent that corresponding scientific measures are lacking. This study analyzed the spatial and temporal evolution characteristics and drivers of WC in the TRB from 1990 to 2019 based on the water yield module of the Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST) model. The results showed that: 1) under the combined effect of nature and socioeconomics, the WC depth of the TRB has slowly increased at a rate of 0.11 mm/yr in the past 30 years, with an average WC depth of 36.14 mm. 2) The main driving factor of the spatial variation in WC is precipitation, there is a significant interaction between precipitation and velocity, the interaction between each factor is higher than the contribution of a single factor, and the interactions between factors all have nonlinear enhancement and two-factor enhancement. 3) Among the seven counties and municipalities in the study area, the southern part of Helong City and the southeastern part of Longjing City are extremely important areas for WC(> 75 mm), and they should be regarded as regional water resources and ecological priority protection areas. It is foreseen that under extreme climate conditions in the future, the WC of the watershed is under great potential threat, and protection measures such as afforestation and forestation should begin immediately. Furthermore, the great interannual fluctuations in WC depth may place more stringent requirements on the choice of time scales in the ecosystem service assessment process.展开更多
Understanding the effects of land cover changes on ecosystem carbon stocks is essential for ecosystem management and environmental protection, particularly in the transboundary region that has undergone marked changes...Understanding the effects of land cover changes on ecosystem carbon stocks is essential for ecosystem management and environmental protection, particularly in the transboundary region that has undergone marked changes. This study aimed to examine the impacts of land cover changes on ecosystem carbon stocks in the transboundary Tumen River Basin(TTRB). We extracted the spatial information from Landsat Thematic Imager(TM) and Operational Land Imager(OLI) images for the years 1990 and 2015 and obtained convincing estimates of terrestrial biomass and soil carbon stocks with the InVEST model. The results showed that forestland, cropland and built-up land increased by 57.5, 429.7 and 128.9 km2, respectively, while grassland, wetland and barren land declined by 24.9, 548.0 and 43.0 km2, respectively in the TTRB from 1990 to 2015. The total carbon stocks encompassing aboveground, belowground, soil and litter layer carbon storage pools have declined from 831.48 Tg C in 1990 to 831.42 Tg C in 2015 due to land cover changes. In detail, the carbon stocks decreased by 3.13 Tg C and 0.44 Tg C in Democratic People's Republic of Korea(North Korea) and Russia, respectively, while increased by 3.51 Tg C in China. Furthermore, economic development, and national policy accounted for most land cover changes in the TTRB. Our results imply that effective wetland and forestland protection policies among China, North Korea, and Russia are much needed for protecting the natural resources, promoting local ecosystem services and regional sustainable development in the transnational area.展开更多
The trans-boundary scope of the Tume n River Basin(TRB)going through China,Russia and DPRK has been defined,and on the basis of this,status of urbanization and its impacts on water environment in recent 20years in TRB...The trans-boundary scope of the Tume n River Basin(TRB)going through China,Russia and DPRK has been defined,and on the basis of this,status of urbanization and its impacts on water environment in recent 20years in TRB have been analyzed.Urbanizatio n in TRB can be characterized as:1)There is medium level of overall urbanization in TRB.Certain distance still exists compared with developed countries.And it is lower than the average urbanization level of Russia and higher than that o f China.2)There is unbalanced distribution of urbanization development in TRB.Urbanization in China part owns the c haracter of low starting point and hi gh-speed development.In Russia part,charac-ter of urbanization can be described as high starting point and stable development.In DPRK part,urbanizatio n level is low,and motive power lacks.3)Due to large population,in China part there is broader region urbanized,larger radius and higher frequency of human activities,which lead to heavier pressure on environment.Meanwhile,the paper has point-ed that impacts of urbanization on wa ter environment are as follows:1)Urban population growth and industr y develop-ment increase the demand for freshwa ter,and also exacerbate the contrad iction between limited water supply and increas-ing freshwater demand.2)Urban infrastructure doesn’t match with urban productive function especially treatment facili-ties,which results in the pollution of the Tumen River.3)The pollution situation in the Tumen River got peak point in1995,and presently,such situation has been improved in great scale,due to effective interventions adopted.However,there still exist 2enterprises that are urgent to be harnessed.Moreover,pollution of municipal sewage will become more and more apparent.4)The influence of urbanization on soil is mainly caused by industrial effl uent and slag,and pollut-ed water irrigation.Soil and water l oss has also been a serious problem caused by urbanization.5)Urbanization results in the decrease of wetlands area.Fur thermore,the paper has given a brief account of the perspective and recom menda-tions on urbanization and environme ntal impacts.展开更多
基金Under the auspices of National Natural Science Foundation of China (No. 41830643)the Scientific Research Project of the Education Department of Jilin Province (No. JJKH20210567KJ)+1 种基金the Doctoral Research Start-up Fund (No.[2020]35)Scientific Development Project (No.[2019]2) of Yanbian University。
文摘The water conservation(WC) function of ecosystems is related to regional ecological security and the sustainable development of water resources, and the assessment of WC and its influencing factors is crucial for ecological and water resource management.The Tumen River Basin(TRB) is located in the core of the Northeast Asian ecological network and has been experiencing severe ecological crises and water shortages in recent years due to climate change and human activities. However, these crises have not been fully revealed to the extent that corresponding scientific measures are lacking. This study analyzed the spatial and temporal evolution characteristics and drivers of WC in the TRB from 1990 to 2019 based on the water yield module of the Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST) model. The results showed that: 1) under the combined effect of nature and socioeconomics, the WC depth of the TRB has slowly increased at a rate of 0.11 mm/yr in the past 30 years, with an average WC depth of 36.14 mm. 2) The main driving factor of the spatial variation in WC is precipitation, there is a significant interaction between precipitation and velocity, the interaction between each factor is higher than the contribution of a single factor, and the interactions between factors all have nonlinear enhancement and two-factor enhancement. 3) Among the seven counties and municipalities in the study area, the southern part of Helong City and the southeastern part of Longjing City are extremely important areas for WC(> 75 mm), and they should be regarded as regional water resources and ecological priority protection areas. It is foreseen that under extreme climate conditions in the future, the WC of the watershed is under great potential threat, and protection measures such as afforestation and forestation should begin immediately. Furthermore, the great interannual fluctuations in WC depth may place more stringent requirements on the choice of time scales in the ecosystem service assessment process.
基金Under the auspices of the National Key Research and Development Project(No.2016YFA0602301)National Natural Science Foundation of China(No.41730643,41671219,41771109,31500400)
文摘Understanding the effects of land cover changes on ecosystem carbon stocks is essential for ecosystem management and environmental protection, particularly in the transboundary region that has undergone marked changes. This study aimed to examine the impacts of land cover changes on ecosystem carbon stocks in the transboundary Tumen River Basin(TTRB). We extracted the spatial information from Landsat Thematic Imager(TM) and Operational Land Imager(OLI) images for the years 1990 and 2015 and obtained convincing estimates of terrestrial biomass and soil carbon stocks with the InVEST model. The results showed that forestland, cropland and built-up land increased by 57.5, 429.7 and 128.9 km2, respectively, while grassland, wetland and barren land declined by 24.9, 548.0 and 43.0 km2, respectively in the TTRB from 1990 to 2015. The total carbon stocks encompassing aboveground, belowground, soil and litter layer carbon storage pools have declined from 831.48 Tg C in 1990 to 831.42 Tg C in 2015 due to land cover changes. In detail, the carbon stocks decreased by 3.13 Tg C and 0.44 Tg C in Democratic People's Republic of Korea(North Korea) and Russia, respectively, while increased by 3.51 Tg C in China. Furthermore, economic development, and national policy accounted for most land cover changes in the TTRB. Our results imply that effective wetland and forestland protection policies among China, North Korea, and Russia are much needed for protecting the natural resources, promoting local ecosystem services and regional sustainable development in the transnational area.
文摘The trans-boundary scope of the Tume n River Basin(TRB)going through China,Russia and DPRK has been defined,and on the basis of this,status of urbanization and its impacts on water environment in recent 20years in TRB have been analyzed.Urbanizatio n in TRB can be characterized as:1)There is medium level of overall urbanization in TRB.Certain distance still exists compared with developed countries.And it is lower than the average urbanization level of Russia and higher than that o f China.2)There is unbalanced distribution of urbanization development in TRB.Urbanization in China part owns the c haracter of low starting point and hi gh-speed development.In Russia part,charac-ter of urbanization can be described as high starting point and stable development.In DPRK part,urbanizatio n level is low,and motive power lacks.3)Due to large population,in China part there is broader region urbanized,larger radius and higher frequency of human activities,which lead to heavier pressure on environment.Meanwhile,the paper has point-ed that impacts of urbanization on wa ter environment are as follows:1)Urban population growth and industr y develop-ment increase the demand for freshwa ter,and also exacerbate the contrad iction between limited water supply and increas-ing freshwater demand.2)Urban infrastructure doesn’t match with urban productive function especially treatment facili-ties,which results in the pollution of the Tumen River.3)The pollution situation in the Tumen River got peak point in1995,and presently,such situation has been improved in great scale,due to effective interventions adopted.However,there still exist 2enterprises that are urgent to be harnessed.Moreover,pollution of municipal sewage will become more and more apparent.4)The influence of urbanization on soil is mainly caused by industrial effl uent and slag,and pollut-ed water irrigation.Soil and water l oss has also been a serious problem caused by urbanization.5)Urbanization results in the decrease of wetlands area.Fur thermore,the paper has given a brief account of the perspective and recom menda-tions on urbanization and environme ntal impacts.
