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Effective agricultural practices can enable and sustain rural livelihoods, particularly in rapidly developing and transforming areas such as the Chinese Loess Plateau. Drawing from the Sustainable Livelihoods Approach (SLA), a conceptual framework for agricultural practices and sustainable rural livelihoods for the Yangou watershed within the Chinese Loess Plateau is presented and discussed. It is found that agricultural practices that include building terraces, returning sloped farmlands to forestland and grassland, and expanding orchards all have had positive and significant impacts on farmers' livelihood assets, strategies, outcomes, and vulnerabilities. From 1997 to 2006, 48.4 ha (95%) sloped farmland in the Yangou watershed was converted to new land management, and the percentages of income from fruit sale and sale of labor to total income dramatically increased by 59% and 14%, respectively. The watershed community also experienced 159% raise in per capita net income from 1997 to 2003, while the watershed itself experienced a 99% decrease in sediment yield from 1998 to 2007. These positive and significant impacts of new agricultural practices on the sustainable rural livelihoods of the Yangou watershed are evident in the community's reduced dependence upon grain and subsidies income, the diversified strategies for livelihood, and the improved environmental indices. The successful implementation of new agricultural land management practices and policies in the Yangou watershed strongly suggest that similar transformations can be achieved in similar regions throughout China's vast rural areas of the Loess Plateau.  相似文献   
2.
A Permian-Triassic (P-Tr) boundary section of continuous carbonate facies, which well recorded the biotic and environmental processes through the great P-Tr transition in the shallow non-microbialite carbonate facies, has been studied in Yangou, Leping County, Jiangxi Province. The P-Tr sequence is well correlated with the Meishan section according to the conodont biostratigraphy and the excursion of carbon isotopes. A series of high-resolution thin-sections from the P-Tr boundary carbonate rocks at the Yangou section are studied to explore the interrelation between environmental change and biological evolution during the transitional time. Six microfacies have been identified based upon the observation of the thin-sections under a microscope on the grains and matrix and their interrelation. Combined with the data of fossils and carbon isotopes, Microfacies 4 (MF-4), coated-grain-bearing foraminifer oolitic sparitic limestone, and Microfacies 6 (MF-6), dark shelly micritic limestone, should be the different responses to the two episodes of mass extinction and environmental events that can be correlated throughout South China and even over the world. The oolitic limestone of MF-4 is the first finding from the latest Permian strata in South China and it might be a proxy of an unusual environmental condition of high pCO2, low sulfate concentration and of microbial blooming in the aftermath of the latest Permian mass extinction. The micritic limestone of MF-6 containing rich micro-gastropods and ostracods probably represents the blooming event of disaster taxa in the earliest Triassic environment. The microfacies analysis at the Yangou section can well reveal the episodic process of the biological evolution and environmental change in the shallow non-microbialite carbonate facies throughout the great P-Tr transition, thus the Yangou section becomes an important complement to the Meishan section.  相似文献   
3.
黄土丘陵区燕沟流域土地利用变化与优化调控   总被引:47,自引:2,他引:47  
徐勇  Roy C.Sidle 《地理学报》2001,56(6):657-666
采用GIS空间分析技术,分析和概括了1966-2000年期间燕沟流域土地利用变化时空过程及其基本特征:解析了土地利用变化的主要成因;总结了1997年以来土地利用结构优化调控的主要特点;评价了土地利用结构优化调控后的生态环境效益、经济效益及其可持续发展性。籍此希望揭示出黄土丘陵区土地利用变化与优化调控所具有的一些共性特点和规律。  相似文献   
4.
XU Yong  TANG Qing 《地理学报》2009,19(5):577-586
At present, land use optimization at small watershed scale is the key measure to control soil erosion, restore the eco-environment and improve the farmers’ living standard on the Loess Plateau, China. Based on the land use survey maps of 1966, 1988, 1997, 2003 and the digital topographic map of 1984 in Yangou watershed, and assisted by spatial techniques of GIS, the basic characteristics and driving forces of land use change in Yangou watershed are analyzed. According to the summarization of land-use optimization characteristics since 1997, and with the help of continuous monitoring data for years and farmer investigation data, this paper appraises eco-environmental benefits, economic benefits and sustainability of Yangou watershed. We have used sediment reduction benefits, coverage ratio of permanent vegetation, per capita food production and per capita income of farmers as indices. The results show that Yangou watershed project has successfully controlled the soil and water loss and the farmers’ living standard has been improved markedly by reasonable adjustment to land use structure. The benefit of sediment reduction is higher than 80% and the coverage ratio of permanent vegetation reaches 61.03%. In 2006, the per capita income increased by 1493 yuan compared with the year 1998.The successful measures and experiences of Yangou watershed are worth promoting on the Loess Plateau.  相似文献   
5.
刘林 《世界地质》2011,30(2):186-191
从矿床产出特征、成矿物质来源、沉积环境与岩相、赋矿层位与含矿岩系及区域钒矿的对比等方面,对堰沟钒矿成矿地质背景等特征进行研究。结果表明,堰沟钒矿是赋存于早志留世大贵坪组黑色岩系中的沉积型钒矿,广泛分布于平利古陆北缘早志留世大贵坪组黑色岩系中,具有良好的成矿条件和找矿前景。  相似文献   
6.
De-farming slope farmland has been an effective measure in recent years to improve environment and prevent soil and water loss on the Loess Plateau.There are different views about the defarming method,and also various de-farming patterns have been put into practice.This paper takes the Yangou Watershed in Shaanxi Province of China as a case for studying the comprehensive benefits of transforming slope farmland to terraces.Based on the day-by-day meteorological data of the Yan'an station in 2005 and the data...  相似文献   
7.
黄土高原小流域土地利用优化调控   总被引:2,自引:0,他引:2  
At present, land use optimization at small watershed scale is the key measure to control soil erosion, restore the eco-environment and improve the farmers’ living standard on the Loess Plateau, China. Based on the land use survey maps of 1966, 1988, 1997, 2003 and the digital topographic map of 1984 in Yangou watershed, and assisted by spatial techniques of GIS, the basic characteristics and driving forces of land use change in Yangou watershed are analyzed. According to the summarization of land-use optimization characteristics since 1997, and with the help of continuous monitoring data for years and farmer investigation data, this paper appraises eco-environmental benefits, economic benefits and sustainability of Yangou watershed. We have used sediment reduction benefits, coverage ratio of permanent vegetation, per capita food production and per capita income of farmers as indices. The results show that Yangou watershed project has successfully controlled the soil and water loss and the farmers’ living standard has been improved markedly by reasonable adjustment to land use structure. The benefit of sediment reduction is higher than 80% and the coverage ratio of permanent vegetation reaches 61.03%. In 2006, the per capita income increased by 1493 yuan compared with the year 1998. The successful measures and experiences of Yangou watershed are worth promoting on the Loess Plateau.  相似文献   
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