浙江农林大学学报2024，Vol.41Issue(5)：949-958,10.DOI:10.11833/j.issn.2095-0756.20240251
2种水分条件下华北落叶松林的林下日蒸散量变化差异
Difference of daily understory evapotranspiration under two water conditions in Larix principis-rupprechtii plantation
摘要
Abstract
[Objective]The purpose of this study is to explore the impact of soil moisture on the daily understory evapotranspiration in Larix principis-rupprechtii plantation,so as to provide a theoretical basis for understanding the mechanism of forest evapotranspiration adapting to climate change and developing plans for coordinated forest water management.[Method]Taking L.principis-rupprechtii plantation in Diediegou small watershed in semi-arid area of Liupan Mountain in Ningxia as the research object,two experiments(blocking precipitation or water-proof input,and natural precipitation input)were conducted.Soil moisture gradient was artificially increased,and the effects of environmental factors(air temperature,solar radiation intensity,precipitation,and so on)on the daily understory evapotranspiration under the two soil moisture conditions were analyzed.[Result]The daily understory evapotranspiration in August,September and October under natural precipitation condition was 67.06,36.32 and 29.49 mm·d-1,respectively,which was greater than that under water-proof treatment(54.22,20.07,and 11.35 mm·d-1).The daily understory evapotranspiration under the two water conditions was characterized by a gradual decrease,and the fluctuations under natural condition was greater than those under water-proof treatment.From August to October,the difference in daily understory evapotranspiration under both water conditions generally showed a wavy pattern of first increasing and then decreasing,while the ratio showed a gradually increasing wavy pattern.In August,September and October,the mean difference between natural evapotranspiration and water-proof evapotranspiration was 0.41,0.54 and 0.59 mm·d-1,respectively,with ratios of 1.29,1.91 and 2.74,respectively.As the potential evapotranspiration increased,the ratio of daily evapotranspiration difference to soil volumetric water difference under both water conditions gradually increased.The effect of soil moisture on understory evapotranspiration was small when the daily potential evapotranspiration was less than 3 mm·d-1,but increased when the daily potential evapotranspiration was more than 3 mm·d-1,and increased significantly when the daily potential evapotranspiration was more than 5 mm·d-1.[Conclusion]The factors affecting daily understory evapotranspiration are roughly the same under both water conditions.The difference lies in that the daily understory evapotranspiration under natural condition is more affected by precipitation,while that under waterproof treatment is more affected by soil moisture.Future study should focus on the influence of multiple soil moisture gradients on understory evapotranspiration difference.[Ch,7 fig.1 tab.28 ref.]关键词
水分条件/林下蒸散/华北落叶松人工林/半干旱区Key words
water condition/understory evapotranspiration/Larix principis-rupprechtii plantation/semi-arid region分类
林学引用本文复制引用
韩新生,王晓,王彦辉,李振华..2种水分条件下华北落叶松林的林下日蒸散量变化差异[J].浙江农林大学学报,2024,41(5):949-958,10.基金项目
中央级公益性科研院所基本科研业务费专项资金资助项目(CAFYBB2021ZW002) （CAFYBB2021ZW002）
国家自然科学基金区域创新发展联合基金资助项目(U20A2085,U21A2005) （U20A2085,U21A2005）
国家自然科学基金国际(地区)合作与交流项目(42161144008) （地区）
宁夏自然科学基金资助项目(2023AAC03404) （2023AAC03404）
