内蒙古生态环境敏感脆弱,且地处华北上游,其生态环境质量对区域影响重大。针对近年来气候变化和经济快速增长带来的日益突出的生态问题,本文基于GEE平台,融合气溶胶光学厚度(AOD)和荒漠化差值指数(DDI),构建改进型遥感生态指数ARSEI,动...内蒙古生态环境敏感脆弱,且地处华北上游,其生态环境质量对区域影响重大。针对近年来气候变化和经济快速增长带来的日益突出的生态问题,本文基于GEE平台,融合气溶胶光学厚度(AOD)和荒漠化差值指数(DDI),构建改进型遥感生态指数ARSEI,动态监测了2000-2023年内蒙古的生态环境质量,并分析了其空间自相关性。利用CA-Markov模型预测未来内蒙古生态环境质量。结果表明:(1)ARSEI指数的PC1贡献度超过87%,能够有效整合生态指标特征,与传统RSEI相比,更能准确反映内蒙古生态环境质量,具有较强的适用性。(2)2000-2023年,内蒙古地区的生态环境质量以较差和中等为主,空间上呈现自东向西递减分布趋势;2000-2005年退化较重,退化面积占比为21.18%,改善面积占比为8.11%,之后逐渐改善。(3)空间自相关分析显示,内蒙古生态环境质量具有显著的空间集聚性(Moran's I > 0.606),以高-高、低-低集聚为主;空间分布上各等级生态环境质量重心整体呈现自东向西、自北向南改善趋势。(4)预测结果显示,未来内蒙古中西部地区生态环境质量恶化风险高于改善潜力,应关注并采取有效措施遏制退化趋势。展开更多
A stochastic predator-prey system with Markov switching is explored.We have developed a new chasing technique to efficiently solve the Fokker-Planck-Kolmogorov and backward Kolmogorov equations.Dynamic balance and rel...A stochastic predator-prey system with Markov switching is explored.We have developed a new chasing technique to efficiently solve the Fokker-Planck-Kolmogorov and backward Kolmogorov equations.Dynamic balance and reliability of the switching system are evaluated via stationary probability density function and first-passage failure theory,taking into account factors such as switching frequencies,noise intensities,and initial conditions.Results reveal that Markov switching leads to stochastic P-bifurcation,enhancing dynamic balance and reducing white-noise-induced oscillations.But frequent switching can heighten initial value dependence,harming reliability.Further,the influence of the subsystem on the switching system is not proportional to its action probabilities.Monte Carlo simulations validate the findings,offering an in-depth exploration of these dynamics.展开更多
文摘内蒙古生态环境敏感脆弱,且地处华北上游,其生态环境质量对区域影响重大。针对近年来气候变化和经济快速增长带来的日益突出的生态问题,本文基于GEE平台,融合气溶胶光学厚度(AOD)和荒漠化差值指数(DDI),构建改进型遥感生态指数ARSEI,动态监测了2000-2023年内蒙古的生态环境质量,并分析了其空间自相关性。利用CA-Markov模型预测未来内蒙古生态环境质量。结果表明:(1)ARSEI指数的PC1贡献度超过87%,能够有效整合生态指标特征,与传统RSEI相比,更能准确反映内蒙古生态环境质量,具有较强的适用性。(2)2000-2023年,内蒙古地区的生态环境质量以较差和中等为主,空间上呈现自东向西递减分布趋势;2000-2005年退化较重,退化面积占比为21.18%,改善面积占比为8.11%,之后逐渐改善。(3)空间自相关分析显示,内蒙古生态环境质量具有显著的空间集聚性(Moran's I > 0.606),以高-高、低-低集聚为主;空间分布上各等级生态环境质量重心整体呈现自东向西、自北向南改善趋势。(4)预测结果显示,未来内蒙古中西部地区生态环境质量恶化风险高于改善潜力,应关注并采取有效措施遏制退化趋势。
基金Project supported by the National Natural Science Foundation of China(Grant No.12472033)。
文摘A stochastic predator-prey system with Markov switching is explored.We have developed a new chasing technique to efficiently solve the Fokker-Planck-Kolmogorov and backward Kolmogorov equations.Dynamic balance and reliability of the switching system are evaluated via stationary probability density function and first-passage failure theory,taking into account factors such as switching frequencies,noise intensities,and initial conditions.Results reveal that Markov switching leads to stochastic P-bifurcation,enhancing dynamic balance and reducing white-noise-induced oscillations.But frequent switching can heighten initial value dependence,harming reliability.Further,the influence of the subsystem on the switching system is not proportional to its action probabilities.Monte Carlo simulations validate the findings,offering an in-depth exploration of these dynamics.
