title: [Coupling analysis of agro-ecolomic system in gully area of Loess Plateau in 1949-2008: a case study in Changwu County of Shaanxi Province].
abstract: Based on the analysis of the coercing and dynamic evolution relationships between agro-economic system and agro-ecological system, and by using modified entropy method, the weight of each evaluation index for the agro-ecolomic system in Changwu County of Shaanxi Province was determined, and, by employing coupling degree model, the coupling processes of agro-ecolomic system in the gullyarea of Loess Plateau were investigated. From 1949 to 2008, the agro-ecolomic system in the County experienced three stages of "traditional extensive agriculture", "agricultural mechanization", and "agricultural pre-modernization". In corresponding to the implement of national macro policies, the coupling degree of the agro-ecolomic system reached two peaks standing for utmost increasing phase and three valleys standing for coordinate development phase. Periods 1955-1961 and 1984-1992 were the utmost increasing phases of the coupling degree; periods 1962-1965 and 1981-1983 were the rapid transition periods responding to the national-wide policies controlling; while periods 1949-1954 and 1966-1980 were the low-level coordinated development phases. Since 1993, the system had been in the harmonious phase by a spiral development. At present, the system had a potential risk of changing from the harmonious phase to the utmost development phase. Appropriate agricultural policies and better external environment could promote the stable development of the agro-ecolomic system on a harmonious level; otherwise, a retrogressive system might be expected.
authors.affiliation: State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling 712100, Shaanxi, China. jianjunzhang1@163.com
authors.forename: Jian-jun
authors.initials: JJ
authors.lastname: Zhang
authors.forename: Xiao-ping
authors.initials: XP
authors.lastname: Zhang
authors.forename: Ji-jun
authors.initials: JJ
authors.lastname: Wang
authors.forename: Ming-de
authors.initials: MD
authors.lastname: Hao
authors.forename: Jin-peng
authors.initials: JP
authors.lastname: Xu
mesh_terms: D000383:Agriculture / Q000191:economics*; D000531:Altitude; D002681:China; D003247:Conservation of Natural Resources / Q000191:economics*; D004463:Ecology / Q000191:economics*; D017753:Ecosystem; D019277:Entropy; D008962:Models, Theoretical