针对西南干热河谷旱季休闲农田面积扩大的实际，选择旱季初和旱季末2个时段，研究24 h休闲农田温度与农田蒸发量的变化规律及协同关系。结果表明：休闲农田温度曲线和蒸发量累计曲线大致呈现波形函数曲线变化，随着土壤深度和农田覆盖物的增加，曲线依次向后推移，波幅也逐渐变小，表明农田覆盖物对土壤起到一定的稳温和保水作用，可明显降低农田土壤水分散失；休闲农田温度与农田蒸发量的协同函数均呈现正向协同关系，且协同系数普遍较大，随着土壤深度和地表覆盖物逐渐增加，协同关系逐渐减弱，而干旱却有利于协同关系加强，说明在气候干燥区，农田温度升高，农田蒸发量增大，温度与蒸发量的协同关系增强，农田温度仍然是农田蒸发的主要推动因素。故西南干热河谷地区要开发利用季节性休闲农田，就必须做好旱季农田土壤水分的保蓄，增加地表覆盖物，减少农田水分的无效蒸发，为休闲农田的开发利用奠定良好的水分基础。%Aiming at the reality of fallow farmland area enlarging in dry season of southwest dry-hot valley,this pa-per researches the change regulation and synergic relation of fallow farmland temperature with evaporation in 24 hours at the beginning and end of the dry season .The results showed that:The fallow farmland temperature curves and evapora-tion summation curves are mainly presented the change of waveform function curve .With the soil depth and farmland mulch increase,the curves backwardly evolved in proper order,the amplitudes also gradually reduced .It indicated that the farmland mulch will be played a certain function for stable soil temperature and water conservancy,can obviously re-duce the soil moisture losses .The synergic function of fallow farmland temperature with evaporation was presented a posi-tive synergic relationship and the synergic coefficient was generally rather large .But with the soil depth and land surface mulch gradual increase,the synergic relationship will be gradually decreased .Yet the drought will be useful to strengthen the synergic relation .It can illustrate that the land evaporation will be increasing when the farmland temperature going up,so the farmland temperature still is the main driving factor for the farmland evaporation .Therefore to develop and uti-lize the seasonal fallow farmland in the southwest dry-hot valley area,it must be doing best to save and store the soil wa-ter in dry season by adding the land surface mulches,reducing the noneffective evaporation for thr soil moisture,to estab-lish a good water foundation for developing and utilizing the fallow farmland .
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