基于MaxEnt模型的贵州入侵植物大薸适生区预测研究OA

[Objective]Against the threat posed by the invasive species Pistia stratiotes L.(water lettuce)to ecological security and agricultural production in southern China,this study aimed to quantitatively assess its potential suitable habitat distribution patterns in Guizhou Province under current and future climate change scenarios,identify key environmental drivers and priority prevention/control zones,thereby providing a scientific basis for invasive species risk management in karst regions.[Methods]Based on 58 distribution points of Pistia stratiotes in Guizhou Province and integrating 19 bioclimatic variables with elevation data,potential suitable habitats were predicted using the Maximum Entropy model(MaxEnt 3.4.1).Six key environmental variables(bio7,bio8,bio11,bio16,bio17,alt)were selected based on Pearson correlation analysis(|r|>0.80)and model contribution rates.The distribution dynamics for four periods(2021-2100)were simulated coupled with future climate scenarios SSP1-2.6 and SSP5-8.5.The model accuracy was validated using the Area Under the Receiver Operating Characteristic Curve(AUC).Suitable habitats were classified into four levels(Unsuitable,Low,Medium,High)using the Jenks natural breaks classification method.[Results]The MaxEnt model demonstrated excellent predictive reliability(AUC=0.962).The study revealed the core role of hydrothermal coupling during the cold season(December to February);the spatiotemporal overlap of precipitation in the driest quarter(103.19-138.33 mm)and mean temperature in the coldest quarter(7.08-9.76℃)formed a"low temperature-drought"dual-stress mechanism;lower elevation(≤467.24 m)indirectly mitigated stress intensity by elevating cold-season temperatures.Currently,highly suitable habitats(4061.81 km²,2.31%of the province)are concentrated in the lower reaches of the Qingshui River(Congjiang,Rongjiang counties)in Qiandongnan Prefecture and the Duliujiang River Basin(Sandu,Libo counties)in Qiannan Prefecture.Under SSP1-2.6,high-suitability habitats will expand by 29.9%(peak:5277.90 km²)during 2041-2060,followed by a sharp reduction later.Under SSP5-8.5,high-suitability region shows a fluctuating shrinkage,and their proportion decreases to 2.25%at the end of the period.The confluence zone of the Duliujiang and Qingshui Rivers(Congjiang,Rongjiang)and northeastern Qiannan Prefecture(Sandu,Libo)were identified as core prevention and control zones.[Conclusion]The suitability of Pistia stratiotes in Guizhou Province is jointly regulated by the"low temperature-drought"dual-stress mechanism and low-elevation habitats,with karst landform exhibiting a unique response mechanism of"dry-hot valley".Future climate change induces a"mid-term expansion-long-term suppression"divergence pattern in suitable habitats,with significant mid-term expansion risk under the low-emission pathway(SSP1-2.6).The study proposes a watershed-scale hierarchical prevention strategy,providing crucial support for building a precision monitoring and zonal management system in Guizhou Province.