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The different aspects lead to great differences in the processes of water,heat,and energy balance,which further affect the soil environment and the growth of alpine plants. Based on an experimental study with eight aspects（abbreviated as octagonal platform）of Huashixia frozen soil observation base on the Qinghai-Tibet Plateau,the influence of aspects on soil environments and alpine vegetation growth was studied. The results showed that：（1）After 6 years,the soil temperature of each slope near the surface（10 cm and 30 cm depth）from high to low was as follows：south > southeast > southwest > west > east > northwest > northeast > north,that is,the relatively sunny slope（east,southeast,south and southwest）was higher than the relatively shady slope（west,northwest,north and northeast）. However,there was no significant difference in soil water con⁃ tent between the sunny slope and the shady slope at the depth of 0~30 cm. （2）The growth trend of aboveground vegetation（including plant height,coverage and aboveground biomass）on sunny slope was better than that on shady slope. The growth trend of underground vegetation（including root depth and underground biomass）on sunny slope was worse than that on shady slope. （3）In the depth of 0~10 cm,the content of soil organic carbon and total nitrogen on sunny slope was higher than that on shady slope. However,the content of total phosphorus on sunny slope was lower than that on shady slope. There was no significant difference in total potassium and available nutrients among different slopes（P>0. 05）. In general,the effect of temperature on vegetation growth and nutrient distribution is significant in alpine regions,and these findings provides an important reference for vegetation restoration and energy balance research in different aspects. © 2023 The Author(s). 相似文献
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青藏高原海拔高,太阳辐射强,坡向效应显著.其中阴阳坡效应不仅导致多年冻土空间分布格局的差异性,也严重影响了冻土路基工程稳定性.目前虽有大量关于阴阳坡热效应的研究,但定量化和多因素耦合作用的研究,特别是场地内多次重复测量的定量评估研究仍不多见.通过对青藏高原多年冻土区北麓河盆地两个具有相反坡向研究场近4年(2016年9月至2020年5月)近地表温湿度、辐射和风速等野外多重观测资料的分析,研究了高海拔多年冻土区阴阳坡效应对近地表水热及能量平衡的影响.结果表明:在坡向的长期影响下,阴阳坡下垫面性质(辐射、温湿度和土壤质地等)存在较大的差异.其中,阳坡土质相对粗糙,不利于水分的保持,阴坡反之.0.05m深度阳坡(朝南坡向)的日冻融循环次数明显高于阴坡(朝北坡向)o2016-2019年阳坡和阴坡的日冻融循环总次数分别为368和109次,差异非常明显.阳坡各深度土壤温度均显著大于阴坡,温差约1.4℃.浅层地温对地表热量变化的响应速率较快,但随深度的增加阴坡地温的响应速率逐渐滞后于阳坡,且这一现象在融化阶段更为显著.融化阶段,阳坡水分的变化速率较快,随深度的变幅较大,但土壤含水量却明显低于阴坡.地表性质差异如温湿度、反照率和风速等控制着地表能量的交换过程,致使阳坡土壤热通量和短波辐射均大于阴坡.研究对深入理解高海拔、坡地多年冻土区气候—冻土关系及多年冻土模拟边界条件优化具有重要意义. 相似文献
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高海拔多年冻土区坡向差异可引起两坡面的温度场不对称,进而造成基础设施的不均匀沉陷和纵向裂缝。目前坡向效应的研究主要围绕青藏铁路东-西两个坡面而开展的监测与模拟研究,但高原线性工程走向可能涉及不同的方向,其他走向坡面的水热差异状态研究不足。本研究在青藏高原花石峡冻土观测基地建设了一个具有八个坡向的监测实体(称：八棱台),在八个坡面和顶面近地表安装土壤温度、含水量传感器,监测研究坡向差异对坡面近地表水热状态的影响。结果表明：东-西相对坡面近地表温度差异最小,月平均温差为0.1～2.3℃,最大温差出现在5月;而南-北相对坡面近地表温度差异最大,月平均温差为1.3～7.7℃,最大温差出现在2月。其余两个相对坡面近地表温差介于东-西相对坡面和南-北相对坡面之间,其中东北-西南相对坡面温差小于西北-东南相对坡面。仅从近地表坡面温度差异来看,高海拔多年冻土区线性工程南-北走向热稳定性较好,其次是西北-东南向,坡向效应不显著而温度场对称性较好。同样八个坡面近地表土壤体积含水量总体差异为东北-西南相对坡面差异最小,融化期月平均体积含水量差最大为0.06 m3·m-3 相似文献
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