Spatial And Temporal Changes Of Paddy Fields And Dry Land In Liaoning Province And Evaluation Of New Potential Paddy Fields

Cultivated land is the basic condition for human existence,and paddy fields are an important component of cultivated land.A paddy field of a certain scale is an important cornerstone for ensuring the smooth implementation of the food security strategy of "basic grain self-sufficiency and absolute food security".In recent years,corn planting has relatively low benefit and the paddy field reclamation trend is gradually increasing.Therefore,how to scientifically grasp the conversion trend of paddy field dry land,and reasonably predict and evaluate the potential of dry land conversion to paddy field has become a key issue in current research.This article takes Liaoning Province as an example,based on the interpretation data of paddy fields and dry land in Liaoning Province from 1980 to 2015,analyzes the characteristics of the space-time distribution,change and transformation of dry land and paddy field in Liaoning Province in the 35-year period,using principal component analysis The driving factors of spatio-temporal changes of paddy fields and drylands were discussed.Finally,the ARIMA model was used to predict the future development scale of paddy fields,to evaluate the new potential of paddy fields,and to delineate the potential zoning of dry land to paddy fields.The results of this study provide a theoretical and methodological reference for Liaoning Province to carry out the work of arable land occupation-compensation balance and dry land conversion to paddy field.The main research conclusions are as follows:(1)Cultivated land area in Liaoning Province generally shows a decreasing trend from 1980 to 2015,Among them,the paddy field area has been decreasing,while the dry land area increased first and then decreased,but the overall trend is increasing.The cultivated land is mainly dry land,and the paddy field is relatively small.In addition,paddy fields and dry land are mainly distributed in central Liaoning;the comprehensive index of the degree of expansion of paddy field and dry land use shows a trend of decreasing first and then increasing.The comprehensive index of the degree of expansion of paddy field use is 5.55 times that of dry land.In the distribution of the center of gravity,the center of gravity of the dry land changes greatly,and the center of gravity of the paddy field changes little,and the movement direction of the paddy field is opposite to that of the dry land;the transfer of paddy field and dry land is mainly converted from dry land to paddy field and paddy field to dry land.The center of gravity of the dry land changed from Liaozhong County to the north 50.96° to the east of Tiexi District,and then to the east 44.10° of the north to 7.51 km to Xinmin City;the center of dry land to the paddy field moved from Liaozhong County to the south It moves 22.04 km to Liaoyang County in the direction of 288.72° east,and then 8.72 km to Liaozhong County in the direction of 98.93° north to the west,and the proportion of the paddy field converted into dry land is larger than that of dry land converted into paddy field.(2)This study used the qualitative and quantitative combination method to carry out the analysis of the driving factors of the spatio-temporal changes of paddy field and dry land in Liaoning Province.Through qualitative research and analysis,the results showed that the climatic factors such as precipitation and temperature,as well as the total population,rural residents' per capita net income,gross domestic product Social and economic factors such as value,GDP per capita,added value of the primary industry,agricultural output value,etc.have an impact on the spatial and temporal changes of paddy fields and drylands;by screening climate factors,socioeconomic factors,agricultural factors,and using principal components to analyze the quantitative dimensionality reduction The results of the study indicate that socio-economic factors are the main driving factors affecting changes in paddy fields and drylands.The overall population in the study period has shown an increasing trend.Per capita net income of rural residents,GDP,GDP per capita,and the increase of primary industry The value has a significant effect on the spatial and temporal changes of paddy fields and drylands.(3)This study uses the ARIMA model to predict the future development of paddy fields in Liaoning Province.The results show that the paddy field area will show an upward trend from 2019 to 2025,increasing from 93.26×104hm2 to 95.32×104hm2 within 7 years,an increase of 2.06×104hm2.The dynamic degree of paddy field utilization is 0.61%.At the same time,in recent years,high-standard farmland construction projects and policy requirements such as the balance of cultivated land occupation and supplementation are conducive to the implementation of dry land conversion paddy field projects and the expansion of paddy field development.(4)This study refers to the evaluation criteria for rice crops in the Liaoning Province Agricultural Land Grading Regulations.In the past 35 years,a paddy field to dry land area was constructed,a dry land to paddy field suitability evaluation system was constructed,and a dry land to paddy field suitability evaluation was carried out.The evaluation results were divided into highly suitable areas.Moderately suitable area,barely suitable area,unsuitable area.Among them,the highly suitable area is 30.43×103hm2,accounting for 22.19% of the area,and is concentrated in the central plain of Liaoning.It is mainly located in Tai'an County,Shenbei New District,Yuhong District,Heishan County,Xinmin City;moderately suitable The area is 52.52×103hm2,accounting for 38.29% of the area,and is concentrated in the central plain area of Liaoning.It is mainly located in Xinmin City,Changtu County,Liaozhong County,Heishan County,Shenbei New District and other counties;barely suitable area is 34.16×103hm2,with an area ratio of 24.91%,concentrated in the central plain area of Liaoning,mainly located in Faku County,Beizhen City,Xinmin City,Zhangwu County,Zhuanghe City;the area of unsuitable area is 20.05×103hm2,accounting for The ratio is 14.62%,concentrated in the central plains of Liaoning,mainly located in Kangping County,Liaoyang County,Xinmin City,Xifeng County,Zhangwu County and other counties.