基于土地利用方式的巢湖流域氮排放情景模拟OACSTPCD

Land use types and its conversion have a significant impact on nitrogen(N)transport and load for surrounding water-body.However,quantifying the response of N load to the change of land use patterns under different scenarios is still challenging.This study selected Chaohu Basin as the study area.By interpreting land use data at multiple time periods,the PLUS and InVEST models were used to explore the response of N export to various land use changes under different conditions(natural development,cultivated land protection and ecological protection).The investigation results showed that:1)During 2000-2020,the increase of construction land area(626.14 km2)in Chaohu Basin mainly occupied cultivated land(775.64 km2).Urbanization was the main driver of land use change.2)The scenario prediction results of PLUS model showed that the trend of land use change from 2020 to 2030 would be generally consistent with that from 2000 to 2020.However,the conversion frequency among different land use types would decrease.3)According to the simulations using InVEST,the export of N from Chaohu Basin decreased from 4768.04 t in 2000 to 4597.98 t in 2020.The primary reason was that the reduction of N export(340.17 t)due to the reduction of cultivated land area was greater than the increase of N export due to the increase of construction land(170.11 t).4)N export of all land use modes in 2030 would show a decreasing trend compared with 2020.Under the ecological protection scenario,it not only ensured the preservation of ecological function,but also reduced large amount(113.36 t)of N export.From the perspective of reducing N ex-port,it is recommended that the managers should proper design various land types,and strictly control the use of ecological land(e.g.,forest-grassland and water area)for construction.