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Research Review of Post-Evaluation for Comprehensive Benefits of Forestry Ecological Programs
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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
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Assessment of land degradation in Inner Mongolia between 2000 and 2020 based on remote sensing data 被引量:2
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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
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Parameter Ecology for Feedback Vertex Set
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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
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