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1.
土地利用/土地覆被变化对区域生态环境的影响   总被引:8,自引:0,他引:8  
土地利用/ 土地覆被变化对区域生态环境的影响是土地利用/ 土地覆被变化研究的重要内容。本文分析了土地利用/ 土地覆被变化对区域气候、土壤、水量和水质的影响。土地利用/ 土地覆被变化通过改变地表发射率、温室气体和痕量气体的含量影响区域气候;土地利用/土地覆被变化影响着能量交换、水交换、侵蚀与堆积、生物循环和作物生产等土壤主要生态过程,不同土地利用方式和土地覆被类型的空间组合影响着土壤养分的迁移规律;土地利用/ 土地覆被变化对水质的影响主要是通过非点源污染途径,许多非点源污染来源都同土地利用/土地覆被变化紧密联系。文中还探讨了由于人类不合理的土地利用造成的土壤侵蚀、土地退化、水资源短缺、海水入侵等生态环境问题。  相似文献   

2.
基于RS/GIS的南京市土地利用时空变化研究   总被引:5,自引:0,他引:5  
利用1986、1996、2002年同时期的遥感图像数据和地形图,在ArcGIS及其他相关软件的支持下,获得南京市土地利用的现状、动态变化等类专题图。在对土地利用类型变化的幅度和土地利用类型之间转换的时空关系进行了研究后,结果表明:1986—1996—2002年,南京的土地利用变化总趋势是耕地面积迅速减少,林地和水域用地变化不大,开发建设及居住用地迅速增加,唯有重要生态功能的湿地等类型面积急剧减少。城市化进程及工业发展是土地利用发生时空变化的主要原因。  相似文献   

3.
Environmental Science and Pollution Research - The impacts of vegetation cover changes (VCCs) and land use land cover changes (LULCCs) on climate variabilities need to be addressed while...  相似文献   

4.
Noronha L  Siqueira A  Sreekesh S  Qureshy L  Kazi S 《Ambio》2002,31(4):295-302
This article is based on a larger case study that investigated the role of tourist induced and other population movements in causing coastal ecosystem change in Goa, India. It focuses especially upon agro-ecosystems locally known as khazan lands, and sand dunes, and how they are transformed to accommodate the needs of tourists and tourism. The effects of different forms of tourism upon land cover and land-use change is assessed. The research findings suggest that it is not population movements alone that cause ecosystem changes, but the changes in relations between people and ecosystems. This means that in some cases land cover has not changed as much as land use, and in other cases land cover has changed dramatically. Intermediary influences upon land use and land-cover change are also legal, political, and economic factors, particularly changes in property rights.  相似文献   

5.
Environmental Science and Pollution Research - The study on land use and land cover (LULC) changes assists in analyzing the change and regulates environment sustainability. Hence, this research...  相似文献   

6.
Land use data are among the inputs used to determine dry deposition velocities for photochemical grid models such as the Comprehensive Air Quality Model with extensions (CAMx) that is currently used for attainment demonstrations and air quality planning by the state of Texas. The sensitivity of dry deposition and O3 mixing ratios to land use classification was investigated by comparing predictions based on default U.S. Geological Survey (USGS) land use data to predictions based on recently compiled land use data that were collected to improve biogenic emissions estimates. Dry deposition of O3 decreased throughout much of eastern Texas, especially in urban areas, with the new land use data. Predicted 1-hr averaged O3 mixing ratios with the new land use data were as much as 11 ppbv greater and 6 ppbv less than predictions based on USGS land use data during the late afternoon. In addition, the area with peak O3 mixing ratios in excess of 100 ppbv increased significantly in urban areas when deposition velocities were calculated based on the new land use data. Finally, more detailed data on land use within urban areas resulted in peak changes in O3 mixing ratios of approximately 2 ppbv. These results indicate the importance of establishing accurate, internally consistent land use data for photochemical modeling in urban areas in Texas. They also indicate the need for field validation of deposition rates in areas experiencing changing land use patterns, such as during urban reforestation programs or residential and commercial development.  相似文献   

7.
Environmental Science and Pollution Research - Urbanization has led to the rapid and large-scale changes in land use and land cover and has affected the spatial distribution of land surface...  相似文献   

8.
ABSTRACT

Land use data are among the inputs used to determine dry deposition velocities for photochemical grid models such as the Comprehensive Air Quality Model with extensions (CAMx) that is currently used for attainment demonstrations and air quality planning by the state of Texas. The sensitivity of dry deposition and O3 mixing ratios to land use classification was investigated by comparing predictions based on default U.S. Geological Survey (USGS) land use data to predictions based on recently compiled land use data that were collected to improve biogenic emissions estimates. Dry deposition of O3 decreased throughout much of eastern Texas, especially in urban areas, with the new land use data. Predicted 1-hr averaged O3 mixing ratios with the new land use data were as much as 11 ppbv greater and 6 ppbv less than predictions based on USGS land use data during the late afternoon. In addition, the area with peak O3 mixing ratios in excess of 100 ppbv increased significantly in urban areas when deposition velocities were calculated based on the new land use data. Finally, more detailed data on land use within urban areas resulted in peak changes in O3 mixing ratios of ~2 ppbv. These results indicate the importance of establishing accurate, internally consistent land use data for photochemical modeling in urban areas in Texas. They also indicate the need for field validation of deposition rates in areas experiencing changing land use patterns, such as during urban reforestation programs or residential and commercial development.  相似文献   

9.
Average annual net change in soil carbon stocks under past and current management is needed as part of national reporting of greenhouse gas emissions and to evaluate the potential for soils as sinks to mitigate increasing atmospheric CO2. We estimated net soil C stock changes for US agricultural soils during the period from 1982 to 1997 using the IPCC (Intergovernmental Panel on Climate Change) method for greenhouse gas inventories. Land use data from the NRI (National Resources Inventory; USDA-NRCS) were used as input along with ancillary data sets on climate, soils, and agricultural management. Our results show that, overall, changes in land use and agricultural management have resulted in a net gain of 21.2 MMT C year(-1) in US agricultural soils during this period. Cropped lands account for 15.1 MMT C year(-1), while grazing land soil C increased 6.1 MMT C year(-1). The land use and management changes that have contributed the most to increasing soil C during this period are (1) adoption of conservation tillage practices on cropland, (2) enrollment of cropland in the Conservation Reserve Program, and (3) cropping intensification that has resulted in reduced use of bare fallow.  相似文献   

10.
The assessment of spatial and temporal variation of water quality influenced by land use is necessary to manage the environment sustainably in basin scales. Understanding the correlations between land use and different formats of nonpoint source nutrients pollutants is a priority in order to assess pollutants loading and predicting the impact on surface water quality. Forest, upland, paddy field, and pasture are the dominant land use in the study area, and their land use pattern status has direct connection with nonpoint source (NPS) pollutant loading. In this study, two land use scenarios (1995 and 2010) were used to evaluate the impact of land use changes on NPS pollutants loading in basins upstream of Three Gorges Reservoir (TGR), using a calibrated and validated version of the soil and water assessment tool (SWAT) model. The Pengxi River is one of the largest tributaries of the Yangtze River upstream of the TGR, and the study area included the basins of the Dong and Puli Rivers, two major tributaries of the Pengxi River. The results indicated that the calibrated SWAT model could successfully reproduce the loading of NPS pollutants in the basins of the Dong and Puli Rivers. During the 16-year study period, the land use changed markedly with obvious increase of water body and construction. Average distance was used to measure relative distribution patterns of land use types to basin outlets. Forest was mainly distributed in upstream areas whereas other land use types, in particular, water bodies and construction areas were mainly distributed in downstream areas. The precipitation showed a non-significant influence on NPS pollutants loading; to the contrary, interaction between precipitation and land use were significant sources of variation. The different types of land use change were sensitive to NPS pollutants as well as land use pattern. The influence of background value of soil nutrient on NPS pollutants loading was evaluated in upland and paddy field. It was found that total nitrogen (TN) and total phosphorous (TP) in upland were more sensitive to NPS pollutants loading than in paddy fields. The results of this study have implications for management of the TGR to reduce the loading of NPS pollutants into downstream water bodies.  相似文献   

11.
Environmental Science and Pollution Research - Urbanization is the main force of the global environmental as well as land use land cover changes (LULC). Urbanization is caused by prompt increase in...  相似文献   

12.
Environmental Science and Pollution Research - Land use and land cover changes associated with urbanization have had a significant influence on ecosystem services (ESs), but previous studies have...  相似文献   

13.
Environmental Science and Pollution Research - Simulating changes in the value of ecosystem services caused by land use changes in large cities under multiple scenarios is of great significance for...  相似文献   

14.
Schueler V  Kuemmerle T  Schröder H 《Ambio》2011,40(5):528-539
Land use conflicts are becoming increasingly apparent from local to global scales. Surface gold mining is an extreme source of such a conflict, but mining impacts on local livelihoods often remain unclear. Our goal here was to assess land cover change due to gold surface mining in Western Ghana, one of the world’s leading gold mining regions, and to study how these changes affected land use systems. We used Landsat satellite images from 1986–2002 to map land cover change and field interviews with farmers to understand the livelihood implications of mining-related land cover change. Our results showed that surface mining resulted in deforestation (58%), a substantial loss of farmland (45%) within mining concessions, and widespread spill-over effects as relocated farmers expand farmland into forests. This points to rapidly eroding livelihood foundations, suggesting that the environmental and social costs of Ghana’s gold boom may be much higher than previously thought.  相似文献   

15.
Pastoralists face increasing competition for land with crop farmers and nature in and around the W Biosphere Reserve (WBR) in Benin. Our aim was to describe and analyse land use changes in order to understand their drivers, and to describe and analyse the viewpoints of relevant stakeholders in order to understand the competition for land. To this end, remote sensing data, regional statistics, and survey data were collected. We found that crop land expansion around the WBR was the direct driver of decrease of the grazing land area. Population growth and rising demand for food crops, and government support to the cotton sector were indirect drivers of grazing land reduction. Furthermore, competing claims on land among users arose from the complex interaction of crop expansion, presence of WBR and the way it is governed, the lack of support to pastoralists, and the increasing shift of pastoralists’ lifestyle into one of settled crop farmers. Pastoralism is under threat and its survival depends on the successful implementation of policies to support pastoralists and protect grazing lands.  相似文献   

16.
本文以陕北安塞纸坊沟为例,阐述了地块的概念和在地块尺度基础上,研究土地可持续利用的意义。从农业技术因子出发,在地块尺度上评价土地可持续利用发展,强调了人类认识程度、利用因素以及农业技术因子的重要性。从生态的角度,评价地块的土地自然适宜性,与土地利用现状结合评价土地的人为利用适宜性。从生态和经济效益评价两方面进行地块尺度土地可持续性发展评价,并初步建立了评价方法与模型  相似文献   

17.
Environmental Science and Pollution Research - Land use/land cover (LULC) changes impact the structure and functioning of ecosystems, which consequently influences the provisioning of a range of...  相似文献   

18.

Purpose

The aim of this paper is to understand the sustainability of urban spatial transformation in the process of rapid urbanization, and calls for future research on the demographic and economic dimensions of climate change. Shanghai towards its transformation to a metropolis has experienced vast socioeconomic and ecological change and calls for future research on the impacts of demographic and economic dimensions on climate change. We look at the major questions (1) to explore economic and demographic growth, land use and land-cover changes in the context of rapid economic and city growth, and (2) to analyze how the demography and economic growth have been associated with the local air temperature and vegetation.

Method

We examine urban growth, land use and land-cover changes in the context of rapid economic development and urbanization. We assess the impact of urban expansion on local air temperature and vegetation. The analysis is based on time series data of land use, normalized difference vegetation index (NDVI), and meteorological, demographic and economic data.

Results and discussion

The results indicate that urban growth has been driven by mass immigration; as a consequence of economic growth and urban expansion, a large amount of farmland has been converted to paved road and residential buildings. Furthermore, the difference between air temperature in urban and exurban areas has increased rapidly. The decrease of high mean annual NDVI has mainly occurred around the dense urban areas.  相似文献   

19.
Agricultural land use is transforming rapidly in Southeast Asia, often supported by development policies aiming primarily at economic growth. However, the socioeconomic outcomes of these changes for smallholder farmers remain unclear. Here, we systematically review cases of agricultural land use change in Southeast Asia to assess their socioeconomic outcomes and potential trade-off and synergies in these outcomes. Of the 126 reviewed cases, we find mostly positive outcomes for income (SDG 1, 100 cases) and employment (SDG 8, 11 cases), while outcomes on health (SDG 3, 9 cases) were mixed, and outcomes for food security (SDG 2, 44 cases), gender equality (SDG 5, 13 cases), and economic equality (SDG 10, 14 cases) were mostly negative. Studies describing multiple outcomes show indications of synergies between income and food security, and between income and employment, but also potential trade-offs between income and economic equality. In addition, we find that economic land concessions result in multiple negative outcomes more often than other types of land governance regimes. The results provide evidence that economic gains from agricultural land use change often come at a cost of other dimensions of sustainable development.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-022-01712-4.  相似文献   

20.
We designed a soil carbon monitoring system for New Zealand using country-specific land use and soil carbon information. The system pre-stratifies the country by soil type, climate, and land use. Soils were placed in six IPCC soil categories; Podzols were added as they are widespread throughout New Zealand. Temperature was stratified into two categories, each spanning 7 degrees C. Moisture categories were based on water balance, and included five categories. Temperature and moisture stratification was based on the USDA Soil Classification system. Land use (10 categories) was based on 1980s survey data. Overall, 39 combinations of these three factors (cells) described 93% of the New Zealand landscape. Geo-referenced soil carbon data (carbon concentration and bulk density) were used to quantify average soil carbon for each of the 39 cells. Aggregating the polygons gave an estimated 1990 soil carbon baseline of 1152+/-44, 1439+/-73, and 1602+/-167 Mt C (mean+/-S.D.) for the 0-0.1, 0.1-0.3, and 0.3-1.0 m depth increments (not including forest floor carbon). The system described could also be used to quantify equilibrium changes in soil C associated with land-use change if land use is updated periodically.  相似文献   

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