Study On Establishment And Application Of Evaluation Index System For Chemical Fertilization-reduction And Benefit Improvement Technologies In Rice Farming

As the largest grain crop in China,the excessive application of chemical fertilizers in the production of rice poses a great threat to its quality,safety and natural environment.In 2015,The Ministry of Agriculture and Rural Affairs puts forward the action plan for zero growth of fertilizer use by 2020.And in the action assessment of 2016 and 2017,the use of chemical fertilizer decreased year by year.It's urgent to comprehensively evaluate these technologies,whether these satisfy simplification,easy replication,easy promotion and other needs.The purpose of this paper is to evaluate the existing technology pattern,solving the problem that there isn't the unified and standardized evaluation index system and the evaluation model on the reduction of chemical N fertilizer.So that it may provide theoretical basis and reference for the construction and evaluation of other crop index system.This paper,based on a profound understanding of being developed and demonstrated chemical N fertilizer use reduction and efficiency improvement technologies or technological patterns in rice crop production,as well following the principles of scientific and practicality,integrity and conciseness,systematism and hierarchy,dynamic and stability,feasibility and comparability,and reality and directionality,appropriate and leading evaluation indicators system was systematically proposed and established according to literature reviews and specialists opinions in relevant disciplines.Respectively using the grey relational model after combining multiple relevant subjective determining weights methods based on expert opinions,and the principal component analysis model under expert constraint,evaluating the effect of three different combinations of techniques which are relatively matured and put forward the targeted improvement direction through these different advantages and disadvantages.The conclusions in this paper are as follows:1.The index system was constructed,including four levels of technical characteristics,economic benefit,social benefit and environmental benefit which comprised 4 primary indicators,11 secondary indicators and 22 tertiary indicators.2.The principal component analysis model under expert constraint highlight the difference between experts.Due to the formative indicators with higher weight and less uncertainty,the conclusion is more scientific.3.The comparison of assessment in society,economy and environment of three technologies showed that the rice-shrimp co-cropping mode was superior to the rice-tanker cropping mode and the rice-wheat rotation cropping mode.4.The fertilization-reduction and benefit improvement technology needs simplified,eco-friendly and Ensures the economic interests of farmers.Researchers research and develop more favorable technologies faster and better.The government carries out more environmental incentive support policies,such as encourage social service,training of agricultural technology promoters and improvement their treatment,promoting the introduction of these good agricultural techniques,to accelerate the development of high-quality rice production.