A Study On The Impact Of Agricultural Transformation On Changes In Ecosystem Services At The Northern Foot Of The Qinling Mountains

The economic globalization and the rapid development of urban agglomerations by market economic,the country's "three rural" policy,such as the beautiful rural construction,agricultural land conversion,characteristic agricultural development,the changes of agricultural production and the innovation of agricultural technology,are pushing these villages of traditionally cultivated grain to confront both international and domestic market of multifunctional modern agriculture in Xi'an city.Xi'an city is one of the important grain-producing areas in Shaanxi province,under the promotion of agricultural transformation,its land use pattern and landscape pattern have great changes,and agricultural ecosystem services have also been affected deeply.The urbanization has changed the structure and function of agricultural ecosystem.Scholar s who werein the domestic and foreign research the agricultural transformation more focus on exploring the way of agricultural transformation,analyzing the influencing factors of agricultural transformation and using qualitatived methods to analyse the environmental and social problems brought by agricultural transformation,lake using quantitatived method to analysis and measurement the agricultural transformation.On agroecosystem services study,the researchers more focus on assessing the value of large-scale agroecosystem services,analying the change of agroecosystem services by land use and human activities,lack the comprehensive research on small-scale agroecosystem services,the analysis of influence of different agricultural transformation types on ecosystem service change and the impact mechanism between agricultural transformation and ecosystem services.Xiaozhaizi village,Sanqi village,Dujiaozhen village and Jiagou village was selected to represent four agricultural transformation processes such as "grain-fruit","grain-fruit,vegetables","grain-grain,fruit" and"grain-seedling",using Arcgis 10.2,remote sensing image,field mapping and household interview and other means to obtain basic data,combined with the mathematical statistics analysis method,selected production economy,tourism and leisure,environmental purification,carbon sequestration and oxygen release,water conservation,climate regulation and biodiversity protection as indicators of agro-ecosystem services to measure the value of ecosystem services in four agricultural transitions.Through literature review method,this study define the concept of agricultural transformation and put forward the intensity of agricultural transformation.Selected the change of land use,the change of planting structure,level of technology,mode of production and input of production as evaluation indexs of agricultural transformation intensity,using quantitative method to measure the intensity of agricultural transformation.On the basis,this paper analyzes the four agricultural transformation and the changes of agro-ecosystem services from 1985 to 2019,explore the reasons of the change and reveal the influencing mechanisms of four agricultural transformations and agro-ecosystem services.It provides a basis for the transformation and upgrading of agriculture and sustainable development of agriculture in China.Main conclusions:(1)Through literature review method,this study combs the literature of the definition of agricultural transformation,defines the concept of agricultural transformation.the agricultural transformation is a comprehensive change process including land use type,planting structure,science and technology level,mode of production,input of production and various agricultural functions.This study think the degree of agricultural transformation should be represent by the degree of agricultural landscape changes,agricultural economic changes,and agricultural input changes,named intensity of agricultural transformation.(2)The intensity of agricultural transformation is affected by the change of land use,planting structure,technological level,production mode and input of production.The results show that the transformation intensity of "grain-fruit,vegetable" is the greatest,reached 4.611;the second is the "grain-fruit" transformation,the third is"grain-grain,fruit" transformation,and finally is the "grain-seedling"transformation type.(3)From 1985 to 2019,the "grain-fruit" transformation,"grain-fruit,vegetable" transformation,"grain-grain,fruit" transformation,and "grain-seedling"transformation have undergone great changes in agro-ecosystem services.The agricultural ecosystem services in the transformation of "grain-fruit" and "grain-fruit,vegetables" increased by 467.6%and 1321.6%.The growth rate of "grain-grain,fruit"transformation of agro-ecosystem services was followed by 46.1%,while the "grainseedling" transformation of agro-ecosystem services was slightly increased by 4.2%.Thus,the occurrence of agricultural transformation is conducive to the increase of agro-ecosystem services.In the transformation of "grain-fruit","grain-fruit,vegetable" and "grain-grain,fruit",the production economic function increases obviously and is a major part of the total agroecosystem service,while the production economic value of "grain-seedling" decreases.The value of carbon sequestration and oxygen release in "grain-fruit" transformation and "grain-grain,fruit" transformation decreased,and the carbon sequestration and oxygen release service capacity of "grainseedling" transformation,"grain-fruit,vegetable" transformation was enhanced.(4)In the agricultural transformation,the change of land use and planting structure significantly promoted the increase of production economic function in the transformation of "grain-fruit","grain-fruit,vegetable" and "grain-grain,fruit",and the environmental purification function,water conservation function and biodiversity protection of "grain-seedling" transformation have increased significantly.The improvement of technology promoted the total value of agroecosystem services in this four agricultural transformation.The transformation of production mode improves the ecosystem services of "grain-fruit" transformation,"grain-fruit,vegetable"transformation.(5)The transformation of "grain-fruit,vegetable" and "grain-fruit" can not only promote the value of ecosystem service,increase farmers' income,but also contribute to the sustainable development of ecological environment.However,the value of ecosystem services and farmers' income in the transformation of "grain-grain,fruit" are less.The transformation of "grain-seedling" can promote the sustainable development of farmland ecological environment,but economic benefits of production growth slowly.(6)The greater intensity of agricultural transformation,the higher value of total ecosystem service and the higher value of productive economic function.The transformation intensity of "grain-seedling" was the lowest,but the value increment of carbon sequestration and oxygen release,climate regulation,water conservation,tourism and leisure,environmental purification and biodiversity conservation were the highest.