Evaluation Of Cultivated Land Ecological Elasticity And Analysis Of Its Obstacle Indicators In Shandong Province

China's economy has achieved brilliant achievements since the reform and opening up,along with the near limit of resources utilization and the overload of environment.The scarcity and vulnerability of cultivated land which is the basic conditions for human survival is increasingly prominent.Shandong,as a big agricultural province of China,has seen many problems of arable land ecological security.Based on the status,characteristics and status of cultivated land resources,this paper selects Shandong as the research object to evaluate the ecological elasticity and obstacle factors of cultivated land system.First,this paper attempts to put forward the concept of ecological elasticity in cultivated systems to express the system state under the interaction between the external disturbance and its own adjustments and recovery capacity,based on the stress-strain relations theory in elastomechanics and the self-organization characteristics of cultivated systems.Secondly,the system of functional integrity-structural stability-social development-system recovery evaluation index system is established through the essence of the elastic operation of the cultivated land system.Thirdly,entropy method and comprehensive evaluation model are used to evaluate the ecological elasticity of cultivated land system in Shandong Province in 2008-2015 and the ecological elasticity in 17 cities of Shandong province from the spatial dimension.Finally,based on the factor obstacle model,we made a diagnosis analysis of the obstacles that hindered the improvement of the ecological elasticity of Shandong's cultivated land system in 2008 and 2015.The main conclusions are as follows:(1)The pressure capacity and toughness of the arable land system make it have a certain degree of flexibility which will produce different states under different force.It provides a basis for the transplantation and application on stress-strain relationship theory and elasticity theory.(2)In the past 2008-2015 years,the ecological resilience of the cultivated land system in Shandong province was first rising and then descending,finally gradually tending to a gentle trend with a not high comprehensive level and obvious regional differences.(3)The main obstacles to the improvement of the ecological resilience of the cultivated land system in Shandong Province in 2008 were education,population density,land waste water load,annual precipitation and urbanization rate.However it became to the level of grain yield,the per capita net income of farmers,the degree of integrated mechanization of cultivated land,the amount of unit pesticide spraying,and the application of the unit agricultural fertilizer in 2015.The change of obstacle factors was directly related to the economic development and the way of cultivated land use.At the same time,from the comprehensive results of the obstacle factors of the cultivated land system in 17 cities of Shandong province,the two factors of the land waste water load and the afforestation rate of the built-up area have become the main obstacle factors for the most urban arable land systems.Research conclusion warns that the government and relevant institutions should strengthen the conservation and space control of cultivated land.To improve the ecological resilience of cultivated land system from the aspects of improving the structural stability of cultivated land systems,strengthening agricultural modernization,and coordinating the relationship between cultivated land use and economic development,etc.