Assessment And Prediction Of Land Ecological Security Based On PSR And RBF In Zhuoni County,Gansu Province,China

Zhuoni County,As an important part of the Qinghai-Tibet Plateau,is an important water supply and ecological function area in the Yellow River Basin.It is a restricted prohibition and development zone in the nationally strategic layout of ecological security.In recent years,due to the joint action of natural factors and human factors,serious ecological problems have been caused.So it is extremely urgent to carry out research on land ecological security in Zhuoni County.This paper uses the conceptual model of pressure-status-response(PSR)to evaluate the ecological security of land in Zhuoni County,and uses the(RBF)neural network model to predict Zhuoni County's land ecological security status in the future;Hoping to providing the basis for the construction of civilization.The result showed:(1)During the study period,The land ecological security level in Zhuoni County generally showed an upward trend,but land ecological security experienced two changes and development stages.From 2009 to 2011,the land ecological safety value showed a gradual downward trend.From 2011 to 2016,the land ecological safety value showed a slowly rising trend.The level of land ecological security has gradually increased from "unsafe" to "critical safety." In the entire land ecological security evaluation system,the role of stress is greater,and the status and response take second place.(2)Among the pressure subsystems,the land ecological security pressure mainly comes from environmental pollution pressure and social and economic pressures.Environmental pollution accounts for the dominant factors.In the status subsystem,the land use structure in Zhuoni County in 2009 to 2011 changed significantly,the land type structure was unbalanced,and there was a clear upward and downward fluctuation.This situation has stabilized since 2011 and has significantly improved.The response to environmental governance showed fluctuations,and the overall trend remained upward.However,the decreasing indicated that the protection of the environment should be strengthen in 2012 to 2013.(3)From 2017 to 2020,the level of land-based ecological security would slowly rise from“less safe” in the “safety” status.Among them,the ecological pressure would increase from2017 to 2019,leading to a declining trend in land ecological security.In the future,we must continue to strengthen the protection of cultivated land and using the control over discharging wastewater discharge,pesticides,and chemical fertilizer.(4)In view of the ecological security status of Zhuoni County and the land ecological security issues,some countermeasures and suggestions are proposed.First,in view of the discharge of waste water,the local government should strengthen the supervision and management of the discharge of pollutants from enterprises in the future,require enterprises to strictly implement the discharge standards,increase the intensity of sewage treatment,and centralize the treatment of sewage;Second,strengthen the people's awareness in protection of the soil environment,controlled the amount of chemical fertilizers and pesticides;Third,strengthen land management and establish an ecological compensation mechanism;fourth is to strictly enforce the law and increase penalties when illegal sewage companies are found.