Study On Ecological Vulnerability Mechanism And Early Warning Mechanism Of The Wind Erosion-Prone Area In Henan Province Of The Yellow River Basin

Ecological protection and high-quality development in the Yellow River basin are important elements of the national development strategy for ecological environment protection.The Yellow River floodplain in Henan Province,in the lower reaches of the Yellow River,has a national key prevention area of wind and sand erosion,covering an area of 13696.5 Km~2.The potential wind erosion hazards are serious,and the ecological environment is fragile,which restricts the sustainable development of the regional economy and society.This paper takes the wind erosion prone area of the Yellow River Basin in Henan Province as the research object,applies theories of soil erosion,ecology,and other disciplines,utilizes 1Km resolution Landsat TM remote sensing images,land use,socio-economic statistics,and other data information,based on"3S"technology,field surveys,system dynamics,statistical analysis,and other methods,and estimates the wind erosion modulus and ecological vulnerability of the study area from 2000 to 2020,Based on the study of soil wind erosion characteristics,vulnerability mechanisms,and ecological vulnerability assessment,a wind erosion early warning mechanism for the study area is proposed,providing theoretical basis and technical support for wind erosion prevention and ecological protection in the Yellow River Basin Yellow Plain Henan wind erosion prone area,and providing assistance for ecological protection and high-quality development in the Yellow River Basin.The main conclusions are as follows:(1)The Yellow River Basin was originally formed by the flood of Yellow River crevasses and human interference in previous dynasties.The area of wind erosion prone areas in Henan Province is 13696.5 km~2,mainly distributed in Zhongmu County,Weishi County,Tongxu County,Qi County,Xiangfu District,Lankao County,Fengqiu County,Yanjin County,Changyuan County,Neihuang County,Nanle County,Qingfeng County,Fan County,and other counties(districts).From 2000 to 2020,the average soil wind erosion modulus in the study area reached 6.13t/(hm~2·a),belonging to mild wind erosion;The average soil wind erosion modulus in 2000,2000-2005,2005-2010,2010-2015,and 2015-2020 were5.96t/(hm~2·a),5.93t/(hm~2·a),7.1t/(hm~2·a),7.16t/(hm~2·a),and 4.49t/(hm~2·a),respectively;The total amount of soil wind erosion is 7.9×10~6t,7.89×10~6t,9.45×10~6t,9.54×10~6t,5.98×10~6t,the overall trend of soil wind erosion modulus and total wind erosion is increasing first and then decreasing.The average wind erosion modulus in Xinxiang area is the largest at 6.62t/(hm~2·a),while the average wind erosion modulus in Kaifeng area and Zhongmou county is the smallest at 5.48t/(hm~2·a).Kaifeng area and Zhongmou county have a large wind erosion area and the largest total wind erosion amount.The wind erosion modulus of bare sandy land is 77.4t/(hm~2·a),which is much larger than that of cultivated land and forest grassland.However,due to the small area of sandy land,wind erosion in the study area is mainly caused by cultivated land.Wind power density,annual average rainfall,annual sunshine hours,vegetation coverage,and human activities are the main factors that contribute to the wind erosion prone mechanism in the study area,and a mechanism map of wind erosion has been drawn.(2)Based on the characteristics and vulnerability mechanism of wind erosion in the study area and the SRP model,16 indicators were selected to evaluate ecological vulnerability from three levels:ecological sensitivity,ecological resilience,and ecological vulnerability.The overall ecological vulnerability of the study area is relatively high,with the proportion of ecological vulnerability areas at each level being 59.74%,25.21%,7.52%,4.27%,and 3.26%,respectively;The ecological vulnerability index of the study area increased from 2.43 in 2000to 2.77 in 2015,and then slowly decreased to 2.64 in 2020;The study drew a causal loop diagram of the ecological vulnerability mechanism system,and analyzed it from five feedback loops,revealing the correlation between various ecological vulnerability indicators in the wind erosion prone area of Henan in the Yellow River Plain;Since the implementation of ecological protection and high-quality development in the Yellow River Basin,the overall ecological environment in the study area has shown a benign development,with ecological vulnerability tending to stabilize.(3)The concept and theory of wind erosion early warning mechanism are proposed.According to the principles of timeliness,comprehensiveness,efficiency,and guidance,1warning indicator,4 warning source indicators,and 8 warning indicators are selected.A wind erosion early warning model is established using the neutral model method,and four levels of green warning,yellow warning,orange warning,and red warning are determined.The wind erosion early warning operation diagram and support system are proposed.