毛乌素沙地沙蒿凝结水形成规律及其对水均衡的影响  

Dew formation characteristics of Artemisia ordosica and its influence on water balance in the Mu Us Sandy Land

作　　者：冉彬 张在勇[1,2] 杨京博 许达 宫程程 RAN Bin;ZHANG Zaiyong;YANG Jingbo;XU Da;GONG Chengcheng(Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region,Ministry of Education,Chang’an University,Xi’an 710054,China;School of Water and Environment,Chang’an University,Xi’an 710054,China)

机构地区：[1]长安大学旱区地下水文与生态效应教育部重点实验室,西安710054 [2]长安大学水利与环境学院,西安710054

出　　处：《农业工程学报》2023年第8期111-119,共9页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家自然科学基金青年科学基金项目(41902249);陕西省留学人员科技活动择优资助项目(2020006);陕西省重点研发计划(No.2020SF-405,2021ZDLSF05-01);中央高校基本科研业务费资助项目(300102292201)。

摘　　要：凝结水是干旱半干旱区重要的补给水源,为了探究毛乌素沙地典型植被沙蒿凝结水的形成过程,定量化凝结水量,分析气象因素对凝结水的形成贡献,评价沙蒿凝结水量对水均衡的影响,该研究在毛乌素沙地基于大型称重式蒸渗仪开展了沙蒿凝结水的实时动态观测研究。研究结果表明,沙蒿年凝结水生成量为47.1 mm,占年降水量的19.6%,且寒冷的月份凝结水量高于温暖月份。空气温度与地表温度之差及相对湿度的大小是凝结水形成的重要影响因素。通过增强回归树模型的结果发现,相对湿度对凝结水形成的贡献率最高,为43.4%。考虑沙蒿凝结水量,水均衡方程的误差能够降至5.7%,可提高水资源评价时的精度。该研究可为干旱半干旱地区精确评价水资源量提供重要依据,同时也将深化沙蒿条件下凝结水对水循环影响的认识,为旱区植被生态系统的保护提供了科学依据。Dew is one of the most important supplementary water sources in arid and semi-arid regions.The influence of dew amount on the water balance can be evaluated for water management,ecosystem protection,and the optimization of agricultural practices.Moreover,the influencing factors of dew formation can provide some insights into how climate change may impact water availability and ecosystems.However,it is still unclear in the dew formation,due to the difficulty of observation without considering the dew in the water balance.This study aims to quantify the dew amount for a better understanding of dew formation.A series of lysimeter experiments were carried out to continuously observe the dew amount in the Mu Us desert from October 2020 to September 2021.Among them,the dew amount included the fog,dew,and hoar frost formation.In addition,the meteorological factors were monitored at the experimental site,including air temperature,precipitation,wind speed,relative humidity,net radiation,and surface temperature.All data were recorded every ten minutes.The dew amount was evaluated for the water balance during formation.Boosted regression tree(BRT)model was used to investigate the influence of meteorological factors on dew formation.The results were as follows.(1)The dew amount was 47.1 mm in the experimental period,corresponding to 19.6%of the annual rainfall.The dew started to form at night when the air temperature was significantly higher than the soil surface temperature.The dew was mainly formed from October 2020 to January 2021(cold months),with a maximum amount of 9.00 mm in December 2020,and a minimum of 0.55 mm in June 2021.The dew amount was larger in the colder months than that in the warmer ones.(2)The BRT model showed that the largest contribution(43.4%)was found in the relative humidity to the dew formation.It infers that relative humidity was a key factor in the formation of dew.The contribution rates of the net radiation at night and the wind speed to the dew formation were 21.7%and 15.2%,respectively.The muc

关 键 词：湿度 温度 凝结水 沙蒿 增强回归树模型 水均衡 毛乌素沙地 

分 类 号：S271[农业科学—农业水土工程]