Abstract To investigate oasis-desert microclimate effects, we performed a series of numerical simulations in an idealized oasis-desert system based on an improved computational fluid dynamics (CFD) model for simulating atmospheric boundary layer flows, air temperature and humidity. Numerical simulations were designed based on the hydrometeorological observations obtained during the HiWATER-MUSOEXE (Heihe Watershed Allied Telemetry Experimental Research, Multi-Scale Observation Experiment on Evapotranspiration over heterogeneous land surfaces) campaign. The results are summarized as follows: (1) Oasis-desert interactions are significantly affected by background wind conditions. We observed the oasis-desert local circulation under calm background wind conditions and the oasis thermal internal boundary layer under low wind speed conditions induced by hydrothermal contracts. These interactions will disappear when the background wind speed is sufficiently high, and there is only an oasis dynamic internal boundary layer caused by the aerodynamic roughness length contrast. (2) Oasis-desert interactions lead to a series of microclimate effects, including the oasis cold-wet island effect, air humidity inversion effect within the surrounding desert and oasis wind shield effect, which are important for the stability and sustainability of the oases-desert ecosystem. (3) The hydrothermal conditions due to the difference between the oasis and desert, the vegetation fraction and distribution patterns impact the oasis-desert microclimate effects. The intensity of oasis-desert interactions increases with the land surface temperature (LST) difference in the oasis-desert. The oasis-desert interactions are gradually strengthened with the increase of the vegetation fraction within the oasis. Integrated ecological and economic benefits of the oasis, the oasis vegetation pattern, which includes the croplands and shelterbelts staggered within the oasis and the shelterbelts surrounding the outside, is beneficial to limiting the loss of water vapor and preventing sandstorms from the oasis. The findings of the current study improve the fundamental understanding of the microclimate and provide implications for maintaining the sustainability of oasis-desert ecosystems.

中文翻译：

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研究绿洲-沙漠相互作用区的小气候效应

摘要 为了研究绿洲-沙漠小气候效应，我们基于改进的计算流体动力学 (CFD) 模型在理想化的绿洲-沙漠系统中进行了一系列数值模拟，用于模拟大气边界层流动、空气温度和湿度。数值模拟是根据 HiWATER-MUSOEXE（黑河流域联合遥测实验研究，异质陆地表面蒸散多尺度观测实验）活动期间获得的水文气象观测数据设计的。结果总结如下：（1）绿洲-沙漠相互作用受背景风况的影响显着。我们观察了平静背景风条件下的绿洲-沙漠局部环流和热液合同引起的低风速条件下的绿洲热内边界层。当背景风速足够高时，这些相互作用将消失，仅存在由气动粗糙度长度对比引起的绿洲动力内部边界层。(2) 绿洲-沙漠相互作用导致一系列小气候效应，包括绿洲冷湿岛效应、周围沙漠内的空气湿度逆向效应和绿洲挡风效应，对绿洲的稳定性和可持续性具有重要意义。沙漠生态系统。(3) 由于绿洲和沙漠的差异，热液条件，植被比例和分布模式会影响绿洲-沙漠小气候效应。绿洲-沙漠相互作用的强度随着绿洲-沙漠中地表温度（LST）的差异而增加。随着绿洲内植被比例的增加，绿洲-沙漠相互作用逐渐加强。绿洲综合生态效益和经济效益，绿洲植被格局包括绿洲内部的耕地和防护林与外围的防护林交错，有利于限制绿洲的水汽流失和防止沙尘暴。当前研究的结果提高了对小气候的基本认识，并为维持绿洲-沙漠生态系统的可持续性提供了启示。绿洲-沙漠相互作用的强度随着绿洲-沙漠中地表温度（LST）的差异而增加。随着绿洲内植被比例的增加，绿洲-沙漠相互作用逐渐加强。绿洲综合生态效益和经济效益，绿洲植被格局包括绿洲内部的农田和防护林与外围的防护林交错，有利于限制水汽流失，防止绿洲发生沙尘暴。当前研究的结果提高了对小气候的基本认识，并为维持绿洲-沙漠生态系统的可持续性提供了启示。绿洲-沙漠相互作用的强度随着绿洲-沙漠中地表温度（LST）的差异而增加。随着绿洲内植被比例的增加，绿洲-沙漠相互作用逐渐加强。绿洲综合生态效益和经济效益，绿洲植被格局包括绿洲内部的耕地和防护林与外围的防护林交错，有利于限制绿洲的水汽流失和防止沙尘暴。当前研究的结果提高了对小气候的基本认识，并为维持绿洲-沙漠生态系统的可持续性提供了启示。随着绿洲内植被比例的增加，绿洲-沙漠相互作用逐渐加强。绿洲综合生态效益和经济效益，绿洲植被格局包括绿洲内部的耕地和防护林与外围的防护林交错，有利于限制绿洲的水汽流失和防止沙尘暴。当前研究的结果提高了对小气候的基本认识，并为维持绿洲-沙漠生态系统的可持续性提供了启示。随着绿洲内植被比例的增加，绿洲-沙漠相互作用逐渐加强。绿洲综合生态效益和经济效益，绿洲植被格局包括绿洲内部的耕地和防护林与外围的防护林交错，有利于限制绿洲的水汽流失和防止沙尘暴。当前研究的结果提高了对小气候的基本认识，并为维持绿洲-沙漠生态系统的可持续性提供了启示。包括绿洲内交错排列的农田和防护林以及外围防护林，有利于限制水汽流失，防止绿洲沙尘暴。当前研究的结果提高了对小气候的基本认识，并为维持绿洲-沙漠生态系统的可持续性提供了启示。包括绿洲内交错排列的农田和防护林以及外围防护林，有利于限制水汽流失，防止绿洲沙尘暴。当前研究的结果提高了对小气候的基本认识，并为维持绿洲-沙漠生态系统的可持续性提供了启示。