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1.
以流域作为山-水-林-田-湖-草生命共同体的研究尺度和载体,流域生态学在国家生态文明建设中所发挥的学科支撑作用日益重要。“流域生态系统结构-过程-功能-机制-调控”是流域生态学的研究范式,其中空间结构量化及其指标体系构建是流域生态学开展定量研究的一个关键途径。尽管流域生态系统空间结构量化的指标体系涉及到淡水生态学、陆地生态系统生态学、水土保持学、农业环境学和水利工程学等多个学科,但仍未在流域尺度上形成生态系统空间结构整合量化框架体系。基于此,总结了多个关联学科在流域生态系统空间结构量化的研究方法和成果,着重分析了流域生态学在流域尺度上量化生态系统空间结构的难点,并重点以等级结构和集合生态系统理论为基础构建了流域生态系统空间结构量化指标体系,包括流域整体指标、各结构成分指标和结构成分间关系指标,为量化流域生态系统空间结构和结构成分之间关系提供了新方法,对尝试推动流域生态学在山-水-林-田-湖-草生命共同体的耦合定量研究及评估应用具有重要的科学价值。  相似文献   

2.
Abrupt changes in land use/land cover have often characterized Andean rural landscapes. This is particularly notorious in the Paute River watershed in southern Ecuador. We seek to show how, under tenets of the global economy, rural mountain landscapes suffer constant modifications due to the agricultural practices of dwellers and migrants. Erosion of arable slopes takes center stage in analyzing vulnerability due to the high erodibility factor found in this watershed. By using remote sensing and GIS applications, we analyzed the potential erodibility with intersections of rural development constraining of ecosystem services, including the production of water, food, and cultural values in the Paute River watershed. We found six sources of migratory flows and analyzed topographic and elevation effects in potential erodibility indexes of agroecological options to ameliorate the environmental stress. We identified factors associated with migration trends observed in the area and assessed vulnerability issues of resource management that could prevent deforestation, soil erosion, and acculturation amidst the pressures of development in the region. We conclude that sustainable development options can be implemented with a watershed management approach oriented to diminish emigration. This approach shall be integrative, inclusive, and respectful of the rich biocultural diversity heritage conservation of southern Ecuador.  相似文献   

3.
Individual participation of pollutants in the pollution load should be estimated even if roughly for the appropriate environmental management of a river basin. It is difficult to identify the sources and to quantify the load, especially in modeling nonpoint source. In this study a revised model was established by integrating point and nonpoint sources into one-dimensional Streeter-Phelps (S-P) model on the basis of real-time hydrologic data and surface water quality monitoring data in the Jilin Reach of the Songhua River Basin. Chemical oxygen demand (COD) and ammonia nitrogen (NH_3-N) loads were estimated. Results showed that COD loads of point source and nonpoint source were 134 958 t/yr and 86 209 t/yr, accounting for 61.02% and 38.98% of total loads, respectively. NH_3-N loads of point source and nonpoint source were 16 739 t/yr and 14 272 t/yr, accounting for 53.98% and 46.02%, respectively. Point source pollution was stronger than nonpoint source pollution in the study area at present. The water quality of upstream was better than that of downstream of the rivers and cities. It is indispensable to treat industrial wastewater and municipal sewage out of point sources, to adopt the best management practices to control diffuse pollutants from agricultural land and urban surface runoff in improving water quality of the Songhua River Basin. The revised S-P model can be successfully used to identify pollution source and quantify point source and nonpoint source loads by calibrating and validating.  相似文献   

4.
随着招远市社会经济的发展,人类对环境质量的要求越来越高,人类工程活动对土壤造成的污染问题也逐渐显露,加强土壤环境管理是我国环境保护的一项基础性工作,具有十分重要的意义。为查明界河流域地下水及土壤现状,在界河流域自上游到下游布设监测点位,共取水质分析样品66组和土壤样品19组进行化验,分析了地下水和土壤污染监测数据,总结了招远界河流域的水土污染特征,认为界河上游和中游流域土壤以有机污染为主,下游土壤污染为重金属污染,部分区域叠加有机污染形成复合污染,主要重金属成分为镉、砷、汞。结合环境工程领域的环境修复技术,提出了适宜的水土修复方案,为招远市环境修复提出可行性建议。  相似文献   

5.
黄河上游及源头区生态环境质量综合评价   总被引：2，自引：0，他引：2  
本文简要介绍了利用遥感和地理信息系统技术进行黄河上游及源头区生态环境质量综合评价中,评价因子的获取及其分值和权值的确定,评价模型的建立及评价等级的划分。评价结果表明,该区环境质量具有垂直分带规律,人类不合理的经济活动是影响环境质量的重要因素。  相似文献   

6.
Wetland economic valuation approaches and prospects in China   总被引：1，自引：0，他引：1  
Ecosystem services valuation seeks to increase the social relevance of ecosystem characteristics, the underlying biological mechanisms that support services, by making the contribution of ecosystems to human well-being explicit. Economic valuation can help management by clarifying the full range of benefits and costs of proposed management actions. In the past two decades, economic valuation of wetland ecosystem services has become one of the most significant scientific priorities for wetland protection. In this paper, we provide an overview of ecosystem services, and summarize the main interdisciplinary approaches to measure and value wetland ecosystem services. We identified four main methodological gaps preventing progress on wetland valuation of ecosystem services in China, which are: 1) confusion on terminology like intermediate and final ecosystem services, 2) lack of ecological production functions to link ecosystem characteristics to final ecosystem services, 3) static valuation making it difficult to evaluate the trade-offs and synergies among ecosystem services, and 4) lack of clear guidance on relating ecological compensation programs to conservation targets. Overcoming these gaps is important to inform wetland compensation mechanisms and conservation policies. We propose future research on wetland ecosystem services in China should be focused on: 1) defining final ecosystem services based on beneficiary preferences and underlying biophysical mechanisms, 2) establishing wetland monitoring programs at specific sites to collect data on final ecosystem service indicators and ecosystem characteristic metrics to create ecological production functions for economic valuation and rescaling techniques, and 3) incorporating wetland ecosystem service values into decision-making processes to inform wetland management.  相似文献   

7.
Overwhelming water-deficiency conditions and an unbalanced water supply and demand have been major concerns of both the Chinese government and the general public during recent decades. Studying the spatial-temporal patterns and impact factors that influence water retention in China is important to enhance the management of water resources in China and other similar countries. We employed a revised Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST) model and regression analyses to investigate the water retention service in China. The results showed that the southeastern China generally performed much better than Northwest China in terms of the spatial distribution of water retention. In general, the efficacy of the water retention service in China increased from 2000 to 2014; although some areas still had a downward trend. Water retention service increased significantly(P 0.05) in aggregate in the Qinghai-Tibet Plateau, and the Da Hinggan Mountains and Xiao Hinggan Mountains. However, the service in southwestern China showed a decreasing trend(P 0.05), which would have significant negative impact on the downstream population. This study also showed that in China the changes in water retention service were primarily due to climate change(which could explain 83.49% of the total variance), with anthropogenic impact as a secondary influence(likewise the ecological programs and socioeconomic development could explain 9.47% and 1.06%, respectively). Moreover, the identification of water retention importance indicated that important areas conservation and selection based on downstream beneficiaries is vital for optimization protection of ecosystem services, and has practical significance for natural resources and ecosystem management.  相似文献   

8.
The deteriorating water quality in the Taihu Lake Basin has attracted widespread attention for many years, and is correlated with a sharp increase in the quantity of pollutant discharge such as agricultural fertilizers and industrial wastewater. In this study, several factors were selected for evaluating and regionalizing the water environmental capacity by ArcGIS spatial analysis, including geomorphologic characteristics, water quality goals, water body accessibility, water-dilution channels, and current water quality. Then, the spatial optimization of agriculture and industry was adjusted through overlay analysis, based on the balance between industrial space and water environmental capacity. The results show that the water environmental capacity gradually decreases from the west to the east, in contrast, the pollution caused by industrial and agricultural clustering is distributes along Taihu Lake, Gehu Lake and urban districts. The analysis of the agricultural space focuses on optimizing key protected areas of the Taihu Lake Basin, and the shores of Gehu Lake, optimally adjusting the second protected areas of the Taihu Lake Basin, and generally adjusting the urban areas of Changzhou and Wuxi cities. The analysis of industrial space focuses on optimizing the downtowns of Changzhou and Wuxi cities, optimally adjusting key protected areas and second protected areas of the Taihu Lake Basin, and generally adjusting the south and southwest of Gehu Lake. Lastly, some schemes of industrial and agricultural layouts and policies for the direction of industrial and agricultural development were proposed, reflecting a correlation between industry and agriculture and the water environment.  相似文献   

9.
Severe water erosion is notorious for its harmful effects on land-water resources as well as local societies. The scale effects of water erosion, however, greatly exacerbate the difficulties of accurate erosion evaluation and hazard control in the real world. Analyzing the related scale issues is thus urgent for a better understanding of erosion variations as well as reducing such erosion. In this review article, water erosion dynamics across three spatial scales including plot, watershed, and regional scales were selected and discussed. For the study purposes and objectives, the advantages and disadvantages of these scales all demonstrate clear spatial-scale dependence. Plot scale studies are primarily focused on abundant data collection and mechanism discrimination of erosion generation, while watershed scale studies provide valuable information for watershed management and hazard control as well as the development of quantitatively distributed models. Regional studies concentrate more on large-scale erosion assessment, and serve policymakers and stakeholders in achieving the basis for regulatory policy for comprehensive land uses. The results of this study show that the driving forces and mechanisms of water erosion variations among the scales are quite different. As a result, several major aspects contributing to variations in water erosion across the scales are stressed: differences in the methodologies across various scales, different sink-source roles on water erosion processes, and diverse climatic zones and morphological regions. This variability becomes more complex in the context of accelerated global change. The changing climatic factors and earth surface features are considered the fourth key reason responsible for the increased variability of water erosion across spatial scales.  相似文献   

10.
Payment schemes for environmental services face serious budget constraints in Mexico. Payments are equally distributed among forest owners, and the governmental agencies that make payments to beneficiaries do not evaluate the amount of environmental services produced by forested areas. This lack of evaluation could lead to economic and environmental deficiencies that restrict the possible benefits of such programmes. In general, these programmes do not achieve their conservation objectives, and local beneficiaries are not involved in the design or application of these programmes. Similarly, the Payments for Hydrological Environmental Services (PHES) programme of the State of Mexico, Mexico, makes equal payments to beneficiaries of forested areas considering tree density. The objective of the present work was to create a methodology for determining differentiated payments schemes for hydrological environmental services, prioritising areas that contribute the most to groundwater recharge and promote the participation of society. In the Nevado de Toluca Natural Protected Area, the environmental criteria of forest type, tree density and aquifer overexploitation as well as social participation were considered in a multi-criteria analysis implemented in a Geographic Information System. A methodology was developed to determine differentiated payments based on specific forest characteristics that influence the potential capacity of forests to recharge groundwater reserves in addition to the level of social participation. In particular, social participation is key as it could ensure the viability of PHES programmes as conservation alternatives in forested areas with high groundwater recharge potential.  相似文献   

11.
淮河流域上消化道肿瘤与环境污染的模型分析   总被引：1，自引：0，他引：1  
 自20世纪70年代后期以来,淮河流域不断遭受工业点源污染和其他面源污染,媒体也陆续报道了淮河流域"癌症村"的出现。本文探讨了淮河流域14个监测县5810个行政村的消化道肿瘤与环境因子之间的空间分布规律。作者从流域和行政区划等多维空间角度出发,通过全局的最小二乘法线性回归和稳健回归对环境因子进行筛选分析,以局部地理加权回归方法探测各类环境因子,在不同地区对贝叶斯调整的上消化道肿瘤死亡率的影响程度,建立了消化道肿瘤死亡的风险评估模型,其中,包括地表水水质等级、浅层地下水质量分级、河网密度、土壤多环芳烃含量分级、化肥施用量和经济密度等6类环境危险因素。根据局部回归模型中各监测点环境因子的回归系数和统计学检验结果,提取出当地主要的环境影响因素。从14个监测县区总体上看,地表水水质等级和GDP与肿瘤呈负相关,其他环境因子均与肿瘤死亡存在正相关。但从局部角度看,不同地区环境影响因子种类和影响强度有较大差别。其中淮河流域江苏段以化肥施用量、土壤多环芳烃含量、GDP和河网密度为主要影响因子,安徽段以土壤多环芳烃含量和化肥为主,河南段主要是以地下水质量分级、河网密度和化肥为主,同时河南沈丘县地表水水质等级对当地影响较大。山东段虽然也探测出来部分环境危险因子的存在,但没有发现其与肿瘤死亡的关联关系,尚需进一步深化研究。  相似文献   

12.
Nitrogen retention within a watershed reduces the amount of N exported to the ocean; however, it worsens environmental problems, including surface water eutrophication, aquifer pollution, acid rain, and soil acidification. Here, we adopted the Soil and Water Assessment Tool(SWAT) model to describe the riverine N output and retention effects in the Shanmei Reservoir Basin, a subtropical mountainous basin located in Quanzhou City, Southeast China. The results revealed that farmlands and orchards in the upstream and central parts of the basin were the dominant land use types, which contributed large N yields. Fertilizer application was the key source of riverine N output and N retention within the basin. On average, approximately 64% of anthropogenic N inputs were retained within the basin, whereas 36% of total N was exported to the downstream and coastal areas. The average N retention efficiency was 80% in a dry year, and within the year, N retention occurred in spring and summer and N release occurred in autumn and winter. The annual variation in N retention within the basin was largely dominated by changes in rainfall and runoff, whereas the seasonal characteristics of N retention were mainly affected by fertilization. Even with a large decrease in fertilizer application, owing to the contributions of the residual N pool and river background, the riverine N output still maintained a certain base value. The effects of precipitation, land use types, and agricultural fertilizer on N retention should be comprehensively considered to implement reasonable N management measures.  相似文献   

13.
《山地科学学报》2020,17(3):501-515
An important aspect in the restoration of longitudinal connectivity in rivers and streams is the implementation of fish migration systems at the upstream of the functional hydraulic structures(weirs,drop structures or river sills). The diversity of these existing structures as well as the different locations of these weirs within the river, watershed and riparian zone challenge the design engineers to find new holistic solutions for fish migration systems. The Azuga River study area requires a new synergistic fish migration design system. Being a mountain area,rapid increase in water level is quite frequent,especially after heavy or prolonged rainfalls and during spring snow melt. Therefore, it is necessary to design a specific system for fish migration to meet this location's requirements. Due to the characteristics in this location of the Azuga river, the classic fish migration systems would not be functional. The indigenous/mountain trout is considered as the target species in this paper. Although this is a good swimming species, the use of classical systems could,due to exhaustion, prevent and/or reduce the movement of fish upstream of the two weirs(also known as river sills). This new, comprehensive solution, presented in this paper includes:(i) the restoration and stabilization works of the right bank in the weir study area by using biotechnical measures and(ii) the upstream migration system itself-for supporting the migration of fish on the Azuga River.  相似文献   

14.
本文根据作者参加WMO二区协气象管理技术会议的体会,提出制定气象部门发展战略的观点与思路,即环境分析与对外开拓战略、缩小差距与合作战略、提高气象部门地位与加强管理战略、依靠科技进步与加强人才培养战略、满足用户需要的气象服务战略以及在投入产出的良性循环中发展气象事业的战略:并简述了制定发展战略的基本方法和步骤。  相似文献   

15.
The relationship between landscape patterns and soil conservation, as well as the need for nature-based soil erosion control and landscape pattern optimization, have increasingly gained attention in the scientific and political community in the past decade. With the implementation of a series of afforestation/reforestation projects in the western China, the optimization and management of forest landscape patterns will become more important for soil conservation. In this study, the Bailongjiang Watershed(BLJW), in the western China, was used as a case study to explore the relationship between the forest landscape pattern and soil conservation services using mathematical and spatial statistics methods. A spatially-explicit model called the sediment delivery ratio(SDR) model of the Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST) was used to assess the soil conservation service in each sub-basin of BLJW in 1990, 2002, and 2014, and landscape indices were used to describe changes in forest landscape patterns in each sub-basin. Nine forest landscape indices, including the percentage of landscape(PLAND), largest patch index(LPI), edge density(ED), landscape shape index(LSI), mean patch shape(SHAPE_MN), patch cohesion index(COHESION), landscape division index(DIVISION), splitting index(SPLIT) and aggregation index(AI), were significantly correlated to the soil conservation service. PLAND, AI, LSI and SPLIT of forestland were determined to be the more important landscape indicators. The results also indicated that soil conservation was substantially scale-dependent. The results demonstrated that landscape type diversity greatly affected watershed soil conservation and can be used for forest landscape restoration and management. Furthermore, spatial statistics analysis indicated that the Spatial Lag Model(SLM) was superior to the Ordinary Least Squares(OLS) for soil conservation regressions in 1990 and 2014, while OLS was more appropriate for the regression in 2002. These findings will be useful for enhancing soil conservation and for optimizing mountainous forest landscape patterns for afforestation/reforestation and regional development. Future planning and implementation of ecological restoration should focus more on strategic spatial planning and integrated landscape management with full consideration of future climate, water availability/consumption, hydrological regime, topography, and watershed features, especially on afforestation and revegetation projects in western mountainous China, where the socio-ecological system is fragile and poor.  相似文献   

16.
Based on the observed data in monitored drainage areas and GIS spatial analysis tools, watershed basic database of Shitoukoumen Reservoir Basin was built. The multivariate analysis and redundancy analysis (RDA) were used to analyze the spatial and temporal variations of water quality, identify the key environmental factors and their patterns influencing the spatial variation of water quality, and determine the main types and forms of the non-point source (NPS) pollutant export controlled by the key environmental factors. The results show that different patterns of environmental factors lead to great changes in water quality at spatial and seasonal scales. All selected environmental factors explain 64.5% and 68.2% of the spatial variation of water quality over dry season and rainy season, respectively, which shows clear seasonal difference. Over dry season, residential land is the most important environmental factor, which possesses 35.4% of the spatial variation, and drainage area is the second key environmental factor, which possesses 17.0% of spatial variation in the total variance. Over rainy season, slope length and drainage area are the key environmental factors, which possess 29.3% of the spatial variation together. Residential land influences nitrogen export by changing NH4 +-N and particulate organic nitrogen (PON) discharge over dry season, and drainage area controls phosphorus export by regulating dissolved phosphorus (DP) drainage over dry season and phosphorus associated particulate (PAP) loss over rainy season, respectively. Although slope length is an important environmental factor, it does not influence NPS pollutant export. It is interesting that soil organic matter, as a minor environmental factor, highly determines phosphorus and nitrogen export by enhancing the DP, PAP and PON loss.  相似文献   

17.
山东省基本农田可持续利用研究   总被引：1，自引：0，他引：1  
分析了山东省基本农田的数量、分布和构成状况，对1997--2005年全省及各市的基本农田面积变化情况进行对比，指出基本农田保护中存在的问题及面临的形势，提出实现基本农田可持续利用的对策：数量、质量和环境全面管护；经济效益、社会效益和环境效益相统一；用养结合、保持地力、提高产出水平；划定整备区、储备待补资源；区别对待、协调发展。  相似文献   

18.
The Jinsha River Basin is an important basin for hydropower in China and it is also the main runoff and sediment source area for the Yangtze River,which greatly influence the runoff and sediment in the Three Gorges Reservoir.This study aims to characterize the spatial distribution,inter-annual variation of runoff and sediment load in the Jinsha River Basin,and to analyze the contribution of rainfall and human activities to the runoff and sediment load changes.The monitoring data on runoff,sediment load and precipitation were collected from 11hydrological stations in the Jinsha River Basin from1966 to 2016.The data observed at the outlet of the basin showed that 71.4%of the runoff is from the upper reaches of the Jinsha River Basin and the Yalong River,while 63.3%of the sediment is from the lower reaches(excluding the Yalong River).There is no significant increase in runoff on temporal scale in the Jinsha River Basin,while it has an abrupt change in runoff in both upstream and midstream in 1985,and an abrupt change in downstream in 1980 and2013.The sediment load demonstrated a significantincreasing trend in the upstream,no significant reducing trend in the midstream,but significant reducing trend in the downstream.The sediment load in upstream showed abrupt change in 1987,in midstream in 1978 and 2014,in downstream in 2012.Rainfall dominated runoff variation,contributing more than 59.0%of the total variation,while human activity,including reservoirs construction,the implementation of soil and water conservation projects,is the major factor to sediment load variation,contributing more than 87.0%of the total variation.  相似文献   

19.
The Chinese government adopted six ecological restoration programs to improve its natural environments. Although these programs have proven successful in improving local environments, some studies have questioned their performance when regions suffer from drought. Whether we should consider the effects of drought on vegetation change in assessments of the benefits of ecological restoration programs is unclear. Therefore, taking the Grain for Green Program(GGP) region as a study area, we estimated vegetation growth in the region from 2000–2010 to clarify the trends in vegetation and their driving forces. Results showed that: 1) vegetation growth increased in the GGP region during 2000–2010, with 59.4% of the area showing an increase in the Normalized Difference Vegetation Index(NDVI). This confirmed the benefits of the ecological restoration program. 2) Drought can affect the vegetation change trend, but human activity plays a significant role in altering vegetation growth, and the slight downward trend in the NDVI was not consistent with the severity of the drought. Positive human activity led to increased NDVI in 89.13% of areas. Of these, 22.52% suffered drought, but positive human activity offset the damage in part. 3) Results of this research suggest that appropriate human activity can maximize the benefits of ecological restoration programs and minimize the effects of extreme weather. We therefore recommend incorporating eco-risk assessment and scientific management mechanisms in the design and management of ecosystem restoration programs.  相似文献   

20.
The soil and water conservation practices of ecological restoration（ER）,fish scale pit（FP）,furrow and ridge tillage across the slope（FR）,shrub strips（SS）,and vegetation-covered ridge（VR） are characteristic of the Jixing small watershed of the low mountain and hilly region of Jilin Province,Northeast China. This study aims to elucidate the effects of soil and water conservation practices on soil conditions after the short-term implementation of practices. Soil samples were collected from five soil and water conservation sites（ER,FP,FR,SS,and VR） and two controls（BL and CT） to investigate their properties. To evaluate the influence of soil and water conservation practices on soil quality,an integrated quantitative index,soil quality index（QI）,was developed to compare the soil quality under the different soil and water conservation practices. The results show that not all soil and water conservation practices can improve the soil conditions and not all soil properties,especially soil organic carbon（SOC）,can be recovered under soil and water conservation practice in short-term. Moreover,the QI in the five soil and water conservation practices and two controls was in the following order： ER VR BL FR CT SS FP. ER exhibited a higher soil quality value on a slope scale. In the low mountain and hilly region of Northeast China,ER is a better choice than the conversion of farmlands to planted grasslands and woodlands early in the soil and water conservation program.  相似文献   

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