期刊文献+
共找到5篇文章
< 1 >
每页显示 20 50 100
Research Review of Post-Evaluation for Comprehensive Benefits of Forestry Ecological Programs
1
作者 LIU Yong1 CHEN Jie1 ZHI Ling2 1. Research Institute of Forestry Policy and Information, Chinese Academy of Forestry, Beijing 100091, P.R. China 2. School of Economics and Management, Southwest Forestry College, Kunming 650224, P.R. China 《Chinese Forestry Science and Technology》 2008年第3期16-24,共9页
The paper summarized the meaning of post-evaluation for comprehensive benefits of forestry ecological programs, discussed and reviewed its development process in terms of content, indicators and methodologies, and fin... The paper summarized the meaning of post-evaluation for comprehensive benefits of forestry ecological programs, discussed and reviewed its development process in terms of content, indicators and methodologies, and finally presented its development trend from the perspectives of theoretical research, methodological research and application research. 展开更多
关键词 forestry ecological programs POST-EVALUATION comprehensive benefits
原文传递
Prevalence of vegetation browning in China’s drylands under climate change 被引量:1
2
作者 Li Fu Guolong Zhang +3 位作者 Jianping Huang Ming Peng Lei Ding Dongliang Han 《Geography and Sustainability》 CSCD 2024年第3期405-414,共10页
Vegetation greening has long been acknowledged,but recent studies have pointed out that vegetation greening is possibly stalled or even reversed.However,detailed analyses about greening reversal or increased browning ... Vegetation greening has long been acknowledged,but recent studies have pointed out that vegetation greening is possibly stalled or even reversed.However,detailed analyses about greening reversal or increased browning of vegetation remain scarce.In this study,we utilized the normalized difference vegetation index(NDVI)as an indicator of vegetation to investigate the trends of vegetation greening and browning(monotonic,interruption,and reversal)through the breaks for the additive season and trend(BFAST)method across China’s drylands from 1982 to 2022.It also reveals the impacts of ecological restoration programs(ERPs)and climate change on these vegetation trends.We find that the vegetation displays an obvious pattern of east-greening and west-browning in China’s drylands.Greening trends mainly exhibits monotonic greening(29.8%)and greening with setback(36.8%),whereas browning shows a greening to browning reversal(19.2%).The increase rate of greening to browning reversal is 0.0342/yr,which is apparently greater than that of greening with setback,0.0078/yr.This research highlights that,under the background of widespread vegetation greening,vegetation browning is pro-gressively increasing due to the effects of climate change.Furthermore,the ERPs have significantly increased vegetation coverage,with the increase rate in 2000-2022 being twice as much as that of 1982-1999 in reveg-etation regions.Vegetation browning in southwestern Qingzang Plateau is primarily driven by adverse climatic factors and anthropogenic disturbances,which offset the efforts of ERPs. 展开更多
关键词 China’s drylands ecological restoration programs Climate change Greening to browning reversal BFAST
下载PDF
Assessment of land degradation in Inner Mongolia between 2000 and 2020 based on remote sensing data 被引量:5
3
作者 Linlin Zhao Kun Jia +2 位作者 Xin Liu Jie Li Mu Xia 《Geography and Sustainability》 CSCD 2023年第2期100-111,共12页
Achieving land degradation neutrality(LDN)worldwide is a significant target of the Sustainable Development Goal(SDG15.3).Inner Mongolia,as a typical dryland region in northern China,has carried out several large-scale... Achieving land degradation neutrality(LDN)worldwide is a significant target of the Sustainable Development Goal(SDG15.3).Inner Mongolia,as a typical dryland region in northern China,has carried out several large-scale ecological restoration programs to combat land degradation.However,there is a lack of comprehensive assess-ment of its land degradation situation after ecological programs implementation,which is of great significance to supporting SDG15.3 in China.This study analyzed the land degradation situation using the improved SDG15.3.1 calculation framework based on fine resolution data in Inner Mongolia from 2000 to 2020,and finally compre-hensively evaluated the land status of the whole region and those subject to ecological programs.The results show that net land restoration proportion of various ecological project regions and whole region continues to increase.The scope of the Grain for Green Program(GGP)had the largest proportion of net land restoration while the Natural Reserve Program(NRP)had the lowest proportion from 2000 to 2020.The net land restoration area of Inner Mongolia during 2000-2010 and 2010-2020 was 35,800 km 2 and 65,300 km 2,respectively.Overall,Inner Mongolia has achieved statistically zero growth in land degradation under the governance of ecological restora-tion programs.Therefore,reasonable planning,well monitoring,and timely assessment of ecological restoration programs are crucial to support SDG15.3. 展开更多
关键词 SDG15.3 Land degradation neutrality(LDN) Land degradation ecological programs Inner Mongolia
下载PDF
Changes in Ecosystem Service of Soil Conservation Between 2000 and 2010 and Its Driving Factors in Southwestern China 被引量:17
4
作者 RAO Enming XIAO Yi +1 位作者 OUYANG Zhiyun ZHENG Hua 《Chinese Geographical Science》 SCIE CSCD 2016年第2期165-173,共9页
Human activities significantly alter ecosystems and their services; however, quantifying the impact of human activities on ecosystems has been a great challenge in ecosystem management. We used the Universal Soil Loss... Human activities significantly alter ecosystems and their services; however, quantifying the impact of human activities on ecosystems has been a great challenge in ecosystem management. We used the Universal Soil Loss Equation and county-level socioeconomic data to assess the changes in the ecosystem service of soil conservation between 2000 and 2010, and to analyze its spatial characteristics and driving factors in the southwestern China. The results showed that cropland in the southwestern China decreased by 3.74%, while urban land, forest, and grassland areas increased by 46.78%, 0.86%, and 1.12%, respectively. The soil conservation increased by 1.88 × 10^(11) kg, with deterioration only in some local areas. The improved and the degraded areas accounted for 6.41% and 2.44% of the total land area, respectively. Implementation of the Sloping Land Conversion Program and urbanization explained 57.80% and 23.90% of the variation in the soil conservation change, respectively, and were found to be the main factors enhancing soil conservation. The 2008 Wenchuan earthquake was one of the factors that led to the degradation of soil conservation. Furthermore, industrial adjustment, by increasing shares of Industry and Service and reducing those of Agriculture, has also promoted soil conservation. Our results quantitatively showed and emphasized the contributions to soil conservation improvement made by implementing ecological restoration programs and promoting urbanization. Consequently, these results provide basic information to improve our understanding of the effects of ecological restoration programs, and help guide future sustainable urban development and regional industrial restructuring. 展开更多
关键词 soil conservation ecosystem service Sloping Land Conversion program(SLCP) ecological restoration urbanization southwestern China
下载PDF
Parameter Ecology for Feedback Vertex Set
5
作者 Bart M.P.Jansen Venkatesh Raman Martin Vatshelle 《Tsinghua Science and Technology》 SCIE EI CAS 2014年第4期387-409,共23页
This paper deals with the FEEDBACK VERTEX SET problem on undirected graphs, which asks for the existence of a vertex set of bounded size that intersects all cycles. Due it is theoretical and practical importance,the p... This paper deals with the FEEDBACK VERTEX SET problem on undirected graphs, which asks for the existence of a vertex set of bounded size that intersects all cycles. Due it is theoretical and practical importance,the problem has been the subject of intensive study. Motivated by the parameter ecology program we attempt to classify the parameterized and kernelization complexity of FEEDBACK VERTEX SET for a wide range of parameters.We survey known results and present several new complexity classifications. For example, we prove that FEEDBACK VERTEX SET is fixed-parameter tractable parameterized by the vertex-deletion distance to a chordal graph. We also prove that the problem admits a polynomial kernel when parameterized by the vertex-deletion distance to a pseudo forest, a graph in which every connected component has at most one cycle. In contrast, we prove that a slightly smaller parameterization does not allow for a polynomial kernel unless NP coNP=poly and the polynomial-time hierarchy collapses. 展开更多
关键词 feedback vertex set parameterized complexity parameter ecology program structural parameterizations kernelization
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部