Research On Response Relationship Between Food Security And Ecological Construction In The Loess Plateau

In recent years,water and soil loss in the Loess Plateau has been managed to a certain extent,but with the rapid population growth and the unreasonable development and land use,it still restricts the development of agricultural production and h inders social progress in the region.The project of returning farmland to forests(grass)has a pivotal role in preventing and controlling soil erosion,and it is also highly relevant to food security.Therefore,this study uses the collected basic data to comprehensively apply theories of quantitative geomorphology,landscape ecology,soil erosion dynamics,soil and water conservation and other related disciplines,and combines GIS technology to develop a response relationship between food security and ecological construction in the Loess Plateau region.This study analyzed the impact of returning farmland to forests on grain yield trends in the area,and studied the dynamic changes in land use and food security at different spatial and temporal scales in the area,the grain security in the Loess Plateau was assessed using the grain self-sufficiency index and the arable land pressure index.Finally,the future prediction of food security in the Loess Plateau was carried out,and feasible suggestions and countermeasures were proposed to solve the problem of sustainable agricultural growth and coordinated economic and social development in the Loess Plateau region,and promoting food security in the region and sustainable socio-economic development provide some theoretical support.The main research results of this paper are as follows:(1)The characteristics of land use types and land use areas in the Loess Plateau were analyzed,and the characteristics of land use change and the flow direction between land use areas in the Loess Plateau were analyzed through the land use transfer matrix.In the Loess Plateau,cultivated land,grassland and forest land are the main types of land use in the region.Among them,the cultivated land area experienced a period of first increase and then decrease;the forest land type experienced a period of slow increase-decrease period-rapid incr ease;the area of grassland was decreasing;the urban and rural areas,industrial and mining,and residential land were always in the process of growth;the water area was at a trend of decline;the unused land is in a decreasing trend.(2)Revealing the response relationship between population and grain yield in the Loess Plateau.From 1985 to 2013,the total population of the Loess Plateau showed a linear growth trend.In the past thirty years,the total population of the Loess Plateau increased by 34 million 742 thousand.From 1985 to 2000,the population in the Loess Plateau maintained a relatively high growth rate,with an annual growth rate of over 1%.From 2001,the annual population growth rate showed a downward trend in the fluctuation.After 2010,the annual population growth rate remained at about 0.6%.The grain yield of the Loess Plateau from 1985 to 2013 had roughly gone through three stages:the fluctuation growth stage of 1985?1998,the sharp reduction stage of 1999?2001,and the gradual growth stage of 2002?2013.The total grain output was fluctuated and the fluctuation coefficient varied between-18.73?16.04.The food supply in the entire Loess Plateau is safe,but due to the spatial differences in the distribution of the population and cultivated land,the level of food security differs in different time and space scales.(3)Evaluating the changes in the food security and pressure index of cultivated land in the Loess Plateau.The results show that the variation of grain self-sufficiency coefficient in the Loess Plateau can be divided into three stages.The first stage:From 1985 to 1998,the coefficient of grain self-sufficiency showed an upward trend of fluctuation,but the coefficient was lower than 95%in total,indicating that the grain yield in the Loess Plateau did not meet the demand.The second phase:From 1999 to 2001,the grain self-sufficiency index of the Loess Plateau showed a continuous downward trend.By 2001,the grain self-sufficiency ratio was only 67.7%,which was the lowest level in history.Before the large-scale return of farmland to forest project(before 1999),the pressure index of cultivated land on the Loess Plateau has been stable at about 1.3,indicating that the arable land in the Loess Plateau is under tremendous pressure.(4)Forecasting the future food security in the Loess Plateau.In this paper,GM(1,1)is used to forecast population growth and grain yield per unit area in the Loess Plateau.The forecast results show that by 2030,the population will increase to 15.04 million.The annual population growth rate is 1.23%;the average grain yield is 5363.04kg/hm2,and the average annual grain increase in the next 15 years is 1037.04kg/hm2.