Ecology Resilience Of The Western Sichuan Plateau From 1998 To 2018 Quantitative Study

Ecology Resilience is the ability of an ecosystem to counter external disturbances through self-regulation within the system,including adjusting its state variables and driving parameters,so as to maintain its relative equilibrium state when facing external disturbances.The theory is to explore ecosystem movement.The end point of mechanism and ecosystem function,exploring the resilience of regional ecosystem can promote regional ecological management and protection construction.As the boundary of the Qinghai-Tibet Plateau,the Western Sichuan Plateau is a transitional area of our country’s first and second steps.The unique alpine meadows,alpine swamps and lake wetlands have typical ecological research values.In recent years,due to the impact of global climate change and human activities,the surface ecosystem of the western Sichuan plateau has been degraded and desertified,and some areas have gradually recovered during a series of ecological protection.However,climate change and the development of population needs have made the ecosystem of the western Sichuan plateau.There are uncertainties in the future evolution,so it is necessary to explore the resilience of the regional ecosystem.In this study,the NDVI of the Western Sichuan Plateau from 1998 to 2018 was selected as the ecosystem index,and the steady-state transition detection method was adopted to quantitatively study the Ecology Resilience of the Western Sichuan Plateau.The changes in the ecosystem of the Western Sichuan Plateau from 1998 to 2018 and the ecology of the Western Sichuan Plateau System elastic space-time characteristics.The results of the study showed that:(1)The main ecosystems that account for a large portion of the surface covered area of the Western Sichuan Plateau include alpine meadows,shrubs,grasslands,coniferous forests,swamps,broad-leaved forests,bare land,and arable land.The southeast area was dominated by coniferous and broad-leaved forests and shrubs,the northwest part was mainly composed of alpine meadows,shrubs,swamps,etc.,bare land mainly occurs at high altitudes in the region,and arable land was mainly distributed in the northwest.(2)The change trend of regional NDVI from 1998 to 2018 was mostly manifested as a significant increase.The growth rate of NDVI in different ecosystems was represented by coniferous forest> broad-leaved forest> meadow> shrub forest> grassland> swamp> cultivated land> bare land.The overall NDVI spatial distribution had an opposite trend to the regional elevation and topography.(3)The overall steady-state transition times of the western Sichuan plateau ecosystem are 0～4 times,and the area occupied by 2～3 fluctuations was more.Among different ecosystems,bare land was the most stable,and coniferous forest was the most frequently fluctuating.The steady-state transition direction of the overall ecosystem was positive,indicating that the overall vegetation development trend in recent years was increasing,which was consistent with the trend test results.The steady-state transformation time of the ecosystem was mainly from 2002 to 2004,2009 to 2010,and 2012 to 2014,with a duration of4 to 8 years.The pattern of the change from 2002 to 2004 is relatively strong,followed by subsequent changes.(4)The distribution of the absolute value of the ecosystem elasticity of the West Sichuan Plateau increases from northwest to southeast.The overall elasticity value was 7.71×10-3.The elasticity of the northwest region was better than that of the southeast region.The possible reason was that the southeastern part of the western Sichuan plateau had lower altitude and climate disturbance.The impact was deeper,and the population in the southeastern part of the Western Sichuan Plateau was relatively dense in the northwest,which brings more human disturbance factors.The elasticity of the main ecosystem was coniferous forest<broad-leaved forest<meadow<shrub forest<herb swamp<grassland<arable land<bare land.The change form is gradual weakening or first strengthening and then weakening,and there was a weakening trend at the end of the study period.