Ecological Health Remote Sensing Monitoring And Evaluation Of Terrace Systems In The Mountainous Areas Of Northern Guangxi

China is an ancient agricultural country with a long history of agricultural production,which provides the material foundation and food security for its national economy.The agricultural economy occupies a fundamental position in China’s economy,and solving the problems of rural agriculture is a top priority for poverty alleviation and rural revitalization.Longsheng Autonomous County(hereafter referred to as Longsheng County)was once a national-level poverty-stricken county in China.It lifted itself out of poverty and shed the poverty label in 2018,indicating that the poverty alleviation efforts in Longsheng County have been successful.The entire area of Longsheng County is mountainous,and the cultivated land in the county is mainly terraced fields,which are the main places for local residents to carry out agricultural production.Therefore,understanding the distribution of terraced fields in Longsheng County is of great significance for regional agricultural development.In addition,the process of economic development can lead to changes in the regional ecosystem landscape,which can in turn affect the health of the ecosystem.During the period of poverty alleviation,what changes have occurred in the ecological system health in Longsheng County while promoting economic development? How to ensure the stable health of the ecological system in Longsheng County’s terraced fields while driving regional economic development? The exploration of these issues is of great significance for the high-quality development of the economy,ecological protection,and sustainable development in Longsheng County.Based on this,this study takes Longsheng County as the research area,using the features of high-resolution remote sensing images(GF-1 and GF-6)and terrain factors,combined with object-oriented classification method,to automatically extract the terraced fields in the research area.Based on the extracted terraced field ecosystem,this study evaluates the ecological health status of Longsheng County’s ecosystem,providing theoretical support and reference for the region’s sustainable development and high-quality development.The specific content of the study includes:(1)Using domestic high-resolution remote sensing images such as GF-1 and GF-6 as data sources,this study conducts multiscale segmentation experiments to discuss the optimal segmentation scale for the study area.Then,combining with terrain features and vegetation features and calculating texture features,the object-oriented image classification method is adopted,and the SEa TH algorithm is used for classification feature selection.Taking 2016 and2020 as time nodes,the terraced fields in Longsheng County during the period of poverty alleviation are extracted.The overall accuracy of the extraction in 2016 and 2020 is 0.93 and0.96,respectively.The results of automatic extraction are corrected,and the area of terraced fields in Longsheng County in 2016 is 16353.55 hectares,while the area in 2020 is 15133.06 hectares.Through comparative analysis of the terraced field areas,it is found that the terraced field area in Longsheng County decreased by 1220.19 hectares during the period of poverty alleviation.(2)Based on the concept of the VOR-human activity disturbance cascade model and following the principles of ecological system health evaluation,a evaluation system for the ecological system health of terraced fields was constructed.Remote sensing technology was used to obtain indicator information,and the weight of each indicator in the comprehensive evaluation was determined by principal component analysis.The criterion layer was finally determined to be ecological system vitality,ecological system organization capacity,ecological system resilience,and human activity disturbance.The indicator layer included vegetation coverage,ecological system service value,forest and grassland coverage rate,ratio of cultivated land to forest and grassland area,ecological system resilience,ratio of cultivated land area to urban and rural construction land area,and the weights of the indicator layer were 0.13,0.13,0.18,0.18,0.07,0.19,and 0.12,respectively.(3)To conduct a more targeted evaluation of the health of the terraced ecosystem,the Longsheng terraced ecosystem was divided into 130 small units based on the watershed,and the vitality,organization,resilience,and human disturbance of the ecosystem in 2016 and 2020 were analyzed on a unit-by-unit basis using the VOR-human disturbance cascade model while adhering to the principles of ecosystem health evaluation.The results showed that during the period of poverty alleviation,the vitality,organization,resilience,and human disturbance of the Longsheng terraced ecosystem all showed a downward trend,and the health of the ecosystem also showed a trend of degradation.The study results showed that the health status of the Longsheng terraced ecosystem in 2016 was mostly distributed between general and relatively healthy,while in 2020,the health status was mostly distributed between relatively unhealthy and general.