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1.
In order to explore the regional variability of the effects of land use systems on soil properties, Shouyang County in Shanxi Province and Danling County in Sichuan Province of China were selected as the study areas. Field soil samples of the four land use systems (natural forest, forest plantation, shrubland, and cropland) were collected, respectively, from the two areas. The general statistical tools were used to analyze soil data. The results showed that the influence of land use systems on soil properties was significant. In general, soils in slightly human-disturbed land use systems presented a higher fertility level than those in strongly human-disturbed land use systems in both areas. Furthermore, the impacts of the same land use systems on soil properties showed a distinct regional variability, and even in the same land use system, different farming systems and site management measures (such as irrigation, fertilization, and pesticides) could also lead to the regional heterogeneity in soil properties. The regional variability of land use effects on soil properties reveals the regional variability of the effects of human activities on environmental changes, and could explain the complex relationship between humans and the natural environment in certain ways.  相似文献   

2.
Understanding the effects of land use changes on the spatiotemporal variation of soil organic carbon(SOC)can provide guidance for low carbon and sustainable agriculture.In this paper,based on the large-scale datasets of soil surveys in 1982 and 2009 for Pinggu District—an urban-rural ecotone of Beijing,China,the effects of land use and land use changes on both temporal variation and spatial variation of SOC were analyzed.Results showed that from 1982 to 2009in Pinggu District,the following land use change mainly occurred:Grain cropland converted to orchard or vegetable land,and grassland converted to forestland.The SOC content decreased in region where the land use type changed to grain cropland(e.g.,vegetable land to grain cropland decreased by 0.7 g kg-1;orchard to grain cropland decreased by 0.2 g kg-1).In contrast,the SOC content increased in region where the land use type changed to either orchard(excluding forestland)or forestland(e.g.,grain cropland to orchard and forestland increased by 2.7 and 2.4 g kg-1,respectively;grassland to orchard and forestland increased by 4.8 and 4.9 g kg-1,respectively).The organic carbon accumulation capacity per unit mass of the soil increased in the following order:grain cropland soikvegetable land/grassland soikorchard soikforestland soil.Therefore,to both secure supply of agricultural products and develop low carbon agriculture in a modern city,orchard has proven to be a good choice for land using.  相似文献   

3.
In order to understand land use/land cover changes (LUCC) and the eco-environment response to LUCC in farming- pastoral zone of the northern China during the recent twenty years, Baotou prefecture was selected as a case study area for investigation and quantitative evaluation. Technologies of remote sensing (RS), global positioning system (GPS), geographic information system (GIS), and other statistical methods were employed to implement. Results showed that: (1) During the recent twenty years, the areas of forest lands, grasslands and water were reduced, whereas the areas of other types were enlarged. Parts of forest lands, grasslands, and waters had become farmlands, and about 31.5% of the changed grasslands transferred into unused lands. The newly increased farmlands mainly came from grasslands and unused lands. And the newly increased construction lands mainly came from grasslands and farmlands. (2) Regional eco- environmental quality decreased by 12.6%, for which the land degradation (especially the meadow degeneration) and the developing of the cultivated land were mainly responsible, and their contributions to the regional eco-environment changes were 51.84 and 23.63% respectively. (3) The tendency of LUCC and the eco-environment response to LUCC displayed spatial heterogeneity. It can be concluded that the present agricultural production mode was not sustainable in farming-pastoral zone of northern China. Land degradation, especially meadow degradation induced by over-trampling and overgrazing, and developing of cultivated land were mainly responsible for regional eco-environment deterioration. Changing the cultivated land to forest or grass, however, can relieve deterioration of local eco-environment to some extents. And in the farming-pastoral zone in the northern China, evaluating regional eco-environment responses to LUCC was very necessary due to its fragile eco-environments.  相似文献   

4.
利用2003和2008年两期SPOT5卫星影像,对香港地区土地利用/覆盖变化情况进行监测,探讨和分析了香港地区土地利用类型变化、土地利用程度变化的特征和规律.结果表明5a间香港土地利用变化最大的特点是土地利用总面积略有增加,各土地利用类型中,农用地急剧减少,灌丛和草地显著增加;区域的土地利用效率较高,土地利用程度变化微小,目前已处于缓慢发展期.
Abstract:
Supported by RS and GIS technology and using the SPOT5 remote sensing images of 2003 and2008,the authorsr monitored and analyzed the change in land use/land cover in Hong Kong in this period.The results showed that the land area increased by 220 ha from 2003 to 2008 through reclamation and that of all land use types,cultivation land decreased sharply,but serubland and grassland,most of which were transformed from forest land,increased markedly,which was the most remarkable characteristic change of land use/land cover in the 5 years in Hong Kong.Land use extent index showed but little change(1.75),or the land used for urban development and construction changed very little,and the intensive utilization of land remained high.It is concluded that the land use in Hong Kong has come into a period of slow development.  相似文献   

5.
According to the contemporary ecosystem approach, the linkages of human actions with their environment have to be assessed in an integrative manner. The Driver-Pressure-State-Impact-Response (DPSIR) model is applied to identify and describe processes and interactions in human-environmental systems. An example application from a research project dealing with the development of sustainable management strategies for the agriculture in Jiangsu, China, illustrates the potentials and limitations of its sustainable development. The concept and indicators of ecological integrity are used to assess the indicators in the dimensions of DPSIR between 2003 and 2006. The main drivers included population growth which caused increasing demand for food, growing environmental demands, and rapidly decreasing of land and other natural resources. The main environmental problem was water pollution. The results show that in the dimension of driver, total grain output and agricultural land productivity both increased. Labor intensive agriculture has been promoted to increase agricultural land productivity. In the dimension of pressure, on the positive side, infrastructure got greatly improved, the input level such as total power of machinery, and level of fertilizer use increased, and level of pesticides use decreased, but on the negative side, cultivated land per capita and irrigation rate decreased, natural resources keep decreased. Environmental pollution indicators such as industrial wastewater discharge and acid rain rate increased in Jiangsu Province. In the aspect of state, ecosystem state was improved, plant coverage index increased, biological abundance index increased, fertilizer productivity increased, eco-environmental quality index increased, but land degradation index also increased. In the aspect of impact, output level increased, output efficiency enhanced, farmer’s social economic benefit improved. In the aspect of response, social support was greatly improved, input for environmental governance increased. To assess the effects of environmental governance, Jiangsu government was successful to increase compliance rate of sulfur dioxide emissions, but not so efficient in compliance rate of industrial wastewater discharge.  相似文献   

6.
The purpose of soil monitoring system in Slovakia is better to protect the soils with regard to sustainable land use. The main objective is the observation of soil properties concerning the main threats to soil: soil contamination, salinisation and sodification, decline in soil organic matter (SOM), soil compaction and erosion. Soil monitoring system in Slovakia is consistently running since 1993. Its importance consists of providing the information on changing spatial and temporal variations of soil parameters as well as the evolution of soil quality in topsoil and subsoil. Soil monitoring network in Slovakia is constructed using ecological principles, taking into account all main soil types and subtypes, SOM, climatic regions, emission regions, polluted and non-polluted regions as well as various land use. The results of soil monitoring of 318 sites on agricultural land in Slovakia have been presented. Soil properties are evaluated according to the main threats to soil relating to European Commission recommendation for European soil monitoring performance as follows: soil contamination, soil salinization and sodification, decline in SOM, soil compaction and erosion. The most significant change has been determined in physical properties of soils. The physical degradation was especially manifested in compacted and the eroded soils. About 50% of agricultural land is potentially affected by soil erosion in Slovakia. In addition, decline in SOM and available nutrients indicate the serious facts on evaluation and extension of soil degradation processes during the last period in Slovakia. Obtained measured data and required outputs are reported to Joint Research Centre (JRC) in lspra (Italy) and European Environmental Agency (EEA) in Copenhagen (Denmark). Finally, soil monitoring system thus becomes a basic tool for protection of soils and sustainable land use as well as for the creation of legislatives not only in Slovakia, but in EU, too.  相似文献   

7.
Understanding the effects of land use changes on the spatiotemporal variation of soil organic carbon(SOC)can provide guidance for low carbon and sustainable agriculture.In this paper,based on the large-scale datasets of soil surveys in 1982 and 2009 for Pinggu District—an urban-rural ecotone of Beijing,China,the effects of land use and land use changes on both temporal variation and spatial variation of SOC were analyzed.Results showed that from 1982 to 2009in Pinggu District,the following land use change mainly occurred:Grain cropland converted to orchard or vegetable land,and grassland converted to forestland.The SOC content decreased in region where the land use type changed to grain cropland(e.g.,vegetable land to grain cropland decreased by 0.7 g kg~(-1);orchard to grain cropland decreased by 0.2 g kg~(-1)).In contrast,the SOC content increased in region where the land use type changed to either orchard(excluding forestland)or forestland(e.g.,grain cropland to orchard and forestland increased by 2.7 and 2.4 g kg~(-1),respectively;grassland to orchard and forestland increased by 4.8 and 4.9 g kg~(-1),respectively).The organic carbon accumulation capacity per unit mass of the soil increased in the following order:grain cropland soikvegetable land/grassland soikorchard soikforestland soil.Therefore,to both secure supply of agricultural products and develop low carbon agriculture in a modern city,orchard has proven to be a good choice for land using.  相似文献   

8.
《农业科学与技术》2013,(10):1517-1520,1525
The study has examined the tempo-spatial patterns of cultivated land use change in Jiangsu province. A principal component analysis (PCA) of 18 selected indicators of cultivated land use during the period 1970-2010 identified 2 main pat- terns of change in planting productivity and economic efficiency. A major shift from production-centered pattern to profit-oriented one occurred in 1984, the time of grain yield surplus and the mitigation of population pressure. In response to the impending Opened Market System, there was a notable tendency of higher efficiency and less productivity since 1997, as well as remarkable regional disparity of cultivated land use change spatially. It revealed a relative decrease in grain cropping share, crop- ping scale and cultivation intensity in South Jiangsu, especially in Tai-Lake region, and the reverse in North Jiangsu. Some suggestions for the future were finally dis- cussed from the above findings.  相似文献   

9.
伴随经济的快速发展,追逐经济效益而忽略生态效益的土地利用越来越突出,区域土地系统的生态服务功能降低、所提供的产品与服务严重下降,影响了区域的可持续发展.研究以重庆市沙坪坝区为例,运用生态服务价值的方法,通过对1996-2006年沙坪坝区的土地利用中所诱发的生态效益量进行估算,结合区域经济发展,对未来区域生态状况趋势进行预测.结果表明:沙坪坝区在1996-2006年间的土地利用的生态服务价值由1 332.5×10~4$/hm~2减少为1 214.05×10~4$/hm~2,共减少了118.45×10~4$/hm~2;各乡镇的生态服务价值贡献状况表现不一,有增有减;沙坪坝区未来生态状况主要表现为生态重建区(井口、覃家岗等镇)、生态控制区(土主、西永等镇)、生态保护区(中梁、歌乐山等镇)和生态敏感区(曾家、青木关等镇)4种趋势.
Abstract:
With the rapid development of economy, the problem of seeking economic benefits, regardless of ecological value in land use, became more and more serious, and the reduced ecological service value of the regional land system and the gravely declined supplied products and services influenced the regional sustainable development. Taking Shapingba District in Chongqing as an example and using the ecological service value method, this paper estimated the quantity of ecological benefit induced in land use in Shapingba District from 1996 to 2006. Taking into consideration the local economic development, this paper predicted the future regional ecological condition. The results indicated that from 1996 to 2006, the ecological service value of this district in land use dropped from $1 332.5×10~4/ha to $1 214. 05× 10~4/ha, a decline by $118.45 × 10~4/ha; the conditions of the contribution of ecological service value varied with different towns. Four different trends in development were identified, i.e. ecological rebuilding area (Jingkou town, Qinjiagang town, etc. ), ecological controlling area (Tuzhu town, Xiyong town, etc. ), ecological protecting area (Zhongliang town, Geleshan town, etc. ) and ecologically sensitive area (Zengjia town,Qingmuguan town, etc. ).  相似文献   

10.
At present, the excessive use of the fertilizers and pesticides in the agricultural production has result in hardening of the soil and decrease of the wild animals and can not maintain the sustainable using of land resources. To develop ecological agriculture is a powerful measure to reduce energy consumption, protect environment, and realize the sustainable development of the agriculture. In order to promote the sustainable development of agriculture in Jianshan Farm, this paper by using SWOT analysis method analyzed the strength, weakness, opportunity and threat in the development of the ecological agriculture in Jianshan Farm, based on the experience from domestic and foreign ecological agricultural development, and put forward the countermeasures for the development of the ecological agriculture in order to develop ecological circular agriculture and non-genetic soybean crop protected areas, and to establish soybean-corn rotation area and healthy aquaculture zone, as well as develop new energy industry.  相似文献   

11.
Drylands of the world cover 41%of the Earth's land surface and are a direct source of livelihood for 6.5 billion people, especially in developing countries. However, nearly all drylands are at risk of land degradation as a result of human activities. Poverty and desertification in dryland areas are major problems threatening sustainable agriculture and rural development in dryland areas. Several topics that are significant for sustainable agriculture and rural development for food security and environmental rehabilitation in dryland areas were stressed in this paper.  相似文献   

12.
Young elm trees belt-pumpkin strip intercropping was studied to solve the actual problem of resource losses in the large barren area resulted from reconverting cultivated land into forest in the agro-pastoral ecotone in northern China. The final objective was to realize effective utilization of the barren land with both ecological improvement and economic development. Field experiments were conducted together with laboratory analysis. The results indicated that the soil moisture level was remarkably increased in young elm trees belt-pumpkin strip intereropping because the pumpkin vines covered the gap between pumpkin planting-furrow and elm trees belt. The water use efficiency of the intercropping system was increased by 23.7-163.3% as compared with the single cropping. Elm trees belt-pumpkin strip intercropping changed the sequential succession trend of the grasses growing in the gap of the pumpkin planting-furrow. The annual grasses become the dominant vegetation. The nutritive value as fodder and yield of the annual grasses were also increased remarkably. The biomass of pumpkin, elm trees and grasses under intercropping increased by 24.4, 28.4 and 144.4%, respectively, as compared with those under single cropping. The land use efficiency was increased by 132%. It was also indicated that the soil erosion from the intercropping land was not increased due to pumpkin plantation. The differences in the soil erosion among intercropped area, elm trees belt and pumpkin strip with single cropping were not remarkable. Therefore, it was concluded that young elm trees belt-pumpkin strip intercropping is an effective way to utilize the barren land between the young elm trees belt and realize synergistic enhancement of ecological benefit and economic profit.  相似文献   

13.
Circular agriculture is an inevitable course to realize positive cycle of ecology and harmonious development of rural areas. Beijing's mountainous areas depend on the background and orientation of ecological economy for sustainable development. It is of great significance to explore the development of the circular agriculture in the mountainous areas to facilitate sustainable use of agriculture resources. Beijing's mountainous areas have accumulated considerable experiences in boosting the circular agriculture. By summarizing the modes of circular agriculture in mountainous areas and analyzing their actual practices, the paper proposes we need to give high priority to strengthening publicity efforts, giving full play to resources advantages of mountainous areas, and establishing a management mechanism and operation mechanism to promote the development of circular agriculture in Beijing.  相似文献   

14.
In China, there has been insufficient study of whole food system greenhouse gas(GHG) accounting, which limits the development of mitigation strategies and may preclude the achievement of carbon peak and carbon neutrality goals. The paper presents the development of a carbon extension of NUFER(NUtrient flows in Food chain, Environment and Resources use model), a food system GHG emission accounting model that covers land use and land-use change, agricultural production, and post-production subsect...  相似文献   

15.
To solve the problems of the poverty in rural areas and raise the output efficiency of agriculture, policy is the primary factor. Guiding by good policies, the design of agricultural structure and management technology are the two main technical supports for agricultural development. The authors apply the model to determine the consequences of four so-called poverty alleviation strategies: (i) intensification of production, (ii) diversification of livestock production, (iii) land expansion, and (iv) an exit from agriculture, with a set of regional poverty and biodiversity indicators. Diversification seems to be the most promising poverty reduction strategy, but requires an efficient use of animal manure in cropping systems to avoid environmental problems. Improved nutrient management in cropping systems is effective in reducing the regional nitrogen surplus, but less effective in increasing per capita income. The exit strategy is beneficial for reducing poverty and achieving biodiversity goals, but may have important social consequences, which are not addressed in this study. Further reduction of rural poverty is hampered by labor constraints during the harvesting period of high value crops, such as vegetables and fruits, which calls for research and development in the field of agricultural mechanization.  相似文献   

16.
The lower Ili River Basin is located in semi-arid area, and the annual rainfall is 177mm. Therefore, the irrigation is inevitable for agriculture. Large-scale irrigated agriculture had been developed since 1960's in the lower parts of the river and the total irrigated area is about 32 000 hm2. In the project area, the paddy rice-upland crop rotation has been practiced. Due to the domestic water use for hydropower and agriculture as well as water use among riparian countries, the deficit of water for agriculture in the lower part has been concerned. The authors, therefore, conducted the field survey and water balance analysis of the Akdara irrigation project in the lower Ill River Basin in order to assess the land and water uses. Moreover, the impact of the water use on water environment to the basin was analyzed. The following results were obtained as following (1) the groundwater level in the irrigated district varied from 1.5 m to 3.5 m through year. (2) 1970's groundwater level was drastically raised from 8 m to 3 m and the groundwater had been recharged in this period. (3) Water use efficiency of agriculture, which is the ratio of total evapotranspiration to the total water withdrawal was as low as 0.23.  相似文献   

17.
Understanding soil nutrient distributions and the factors affecting them are crucial for fertilizer management and environmental protection in vulnerable ecological regions.Based on 555 soil samples collected in 2012 in Renshou County,located in the purple soil hilly area of Sichuan Basin,China,the spatial variability of soil total nitrogen(TN),total phosphorus(TP)and total potassium(TK)was studied with geostatistical analysis and the relative roles of the affecting factors were quantified using regression analysis.The means of TN,TP and TK contents were 1.12,0.82 and 9.64 g kg~(–1),respectively.The coefficients of variation ranged from 30.56 to 38.75%and the nugget/sill ratios ranged from 0.45 to 0.61,indicating that the three soil nutrients had moderate variability and spatial dependence.Two distribution patterns were observed.TP and TK were associated with patterns of obvious spatial distribution trends while the spatial distribution of TN was characterized by higher variability.Soil group,land use type and topographic factors explained 26.5,35.6 and 8.4%of TN variability,respectively,with land use being the dominant factor.Parent material,soil group,land use type and topographic factors explained 17.5,10.7,12.0 and 5.0%of TP variability,respectively,and both parent material and land use type played important roles.Only parent material and soil type contributed to TK variability and could explain 25.1 and 13.7%of TK variability,respectively.More attention should focus on adopting reasonable land use types for the purposes of fertilizer management and consider the different roles of the affecting factors at the landscape scale in this purple soil hilly area.  相似文献   

18.
By selecting a typical peak-cluster depression area of karst region in Southwest China, we evaluated the effect of land use types and topographic factors on soil nutrients. Grid and line sampling methods were used to sample soil in depression and slope lands respectively, and classical statistical tools were applied to analyze the spatial variability character of soil organic carbon (SOC), total nitrogen (TN), total phosphorus (TP), total potassium (TK), available nitrogen (AN), available phosphorus (AP), available potassium (AK), pH, and C/N. It was found that land use type was the dominant factor that effected the spatial heterogeneity of SOC, TN, TP, TK, AN, and AP. The content of SOC, TN, and AN decreased with the increase of land use intensity. Due to high fertilizer input, TP and AP in tillage fields were higher than those in the other land use types. TK had no obvious change trend among various land use types. Topographic factors had a significant effect on SOC, TN, TP, AN, AP, AK, and pH. Habitat factor was the dominant factor that effected AK. Altitude factor was the dominant factor for pH. However, all of these factors had no significant effect on C/N. Tillage practice had important effect on soil nutrients loss and soil degradation in the fragile karst ecosystem, and the input of organic manure should be increased in this region.  相似文献   

19.
The land ecosystem service function value contains the gas regulating function value, air purification function value, water conservation value, land conser-vation value, soil nutrient conservation value and maintain biodiversity value. Based on the method of market value and the data of Hubei Statistical yearbook, cultivat-ed land resources of ecosystem service function value is 730 038.69Mil ion in 2007-2009, and 714 774.99 Mil ion in 2010-2012 in Wuhan Metropolitan Area. After three years of development, Wuhan Metropolitan Area of ecological value of cultivated land has increased by about 3.97%. From the point of each composition, the im-portance of gas regulating function of cultivated land resources and water conserva-tion function is the forefront. From the point of spatial distribution, the highest of annual average value of the cultivated land ecological was Huanggang (1.725 bil ion yuan), the lowest was Ezhou (217.868 6 mil ion yuan) in 2010-2012. From the point of space changes, the land ecological value increased only in Qianjiang city, while farmland ecological value in other cities was fal ing The conclusion is of direc-tive significance to the regional land protection policy and the farmland reasonable distribution, for Wuhan Metropolitan Area and other areas.  相似文献   

20.
Harmony Coefficient and Regional Agricultural Systems   总被引:4,自引:0,他引:4  
The regional agricultural system (RAS) can be divided into three subsystems: ecological, economic, and social. This article examines the use of the harmony coefficient (HC), efficacy coefficient, rank of the harmony coefficient (RHC), and its appraising index system within the RAS. The harmony coefficient function was developed using a variance coefficient and then applied to Ziyang District, Yiyang City in Hunan Province (ZYH), China, as a test case. From 1995 to 2002, the HC of RAS increased from 0.2982 to 0.4826 and the RHC increased from 3 to 5, although the HC trend was an "n" type in general. This suggests that the HC was weakly maladjusted and the RAS was not harmonious. The HC of the ecological subsystem decreased from 0.3898 to 0.2850, and its RHC from 4 to 3, with the HC trend following the "n" type. For the economic subsystem, the HC value increased from 0.5767 to 0.7458 and the RHC from 6 to 8. However, the trend in HC for the economic subsystem was of the "U" type. The HC of the social subsystem increased slightly from 0.4948 to 0.4663, and the RHC did not change in value. From the HC trends, the HC curve of the economic subsystem is above the HC curve of ZYH and the HC curve of the ecological subsystem is below the HC curve of ZHY. Hence, the ZHY environment has been destroyed by economic development. Environment and social building should be regarded as important issues in the future and promoting RAS harmony development should be considered. The results of the theoretical analysis match fairly closely with reality, and suggest that the harmony theory is feasible in appraising RAS development phases.  相似文献   

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