气候变化领域集成服务门户(CCPortal): Sap flow changes and climatic responses over multiple-year treatment of rainfall exclusion in a sub-humid black locust plantation

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DOI	10.1016/j.foreco.2019.117730
	Sap flow changes and climatic responses over multiple-year treatment of rainfall exclusion in a sub-humid black locust plantation
	He Q.-Y.; Yan M.-J.; Miyazawa Y.; Chen Q.-W.; Cheng R.-R.; Otsuki K.; Yamanaka N.; Du S.
发表日期	2020
ISSN	0378-1127
卷号	457
英文摘要	Black locust (Robinia pseudoacacia) plantations have been widely established in the semiarid and sub-humid areas of central China. Under the condition of global climate change, which is introducing much uncertainty of precipitation patterns in this region, it is of special significance to investigate their responses to precipitation. Here, we investigated sap flow response to reduced throughfall. Stem sap flow was measured from 2011 to 2017 using Granier-type sensors. By placing waterproof panels within tree rows, about 47.5% precipitation was excluded from treated plots since April 2015. Differences in soil water content gradually increased to 4.3% between treated and control plots with continued throughfall exclusion. Decreased precipitation input significantly reduced the average sap flux density in treated plots by 9.1%–45.3%. The extent of this reduction depended on precipitation in the previous and current years. Transpiration and forest growth were negatively affected by the treatment. Furthermore, sap flow response to environmental factors became insensitive, with the discrepancy increasing with increasing drought duration, but was regained by rainfall recharge to soil water in the first two treatment years. However, prolonged drought might damage transpiration resilience capacity, as the saturated sap flux after soil water recharging during the wet period was still lower than that in the control plot in the latter year. Predawn leaf water potential was significantly lower in the treated plot compared to the control plot, whereas midday leaf water potential was similar. Whole tree hydraulic conductance (GP) was also similar between the two plots, except in extreme drought months when GP was much lower in the treated plot. In addition, the specific leaf area and stomatal density decreased in the treated plot. Therefore, decreases in precipitation would cause a transpiration reduction, weakening the tree's response to meteorological variables and lowering growth and productivity, potentially damaging transpiration resilience. These results suggest that black locust is sensitive to water changes, its capacity of drought tolerant is restrained by the drought time scale or drought severity, the use of such species in reforestation in semiarid regions should be implemented with caution. © 2019 Elsevier B.V.
关键词	Arid regions Climate change Drought Rain Reforestation Soil moisture Transpiration Black locust Drought resistance Global climate changes Meteorological variables Pre-dawn leaf water potentials Precipitation patterns Robinia pseudo-acacia Sap flow Plants (botany)climate change deciduous tree drought global climate leaf area potential evapotranspiration precipitation (climatology)rainfall sap flow sensor throughfall transpiration Drought Precipitation Rain Reforestation Robinia Sap Transpiration China Robinia pseudoacacia
语种	英语
来源机构	Forest Ecology and Management
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/133129
推荐引用方式 GB/T 7714	He Q.-Y.,Yan M.-J.,Miyazawa Y.,et al. Sap flow changes and climatic responses over multiple-year treatment of rainfall exclusion in a sub-humid black locust plantation[J]. Forest Ecology and Management,2020,457.
APA	He Q.-Y..,Yan M.-J..,Miyazawa Y..,Chen Q.-W..,Cheng R.-R..,...&Du S..(2020).Sap flow changes and climatic responses over multiple-year treatment of rainfall exclusion in a sub-humid black locust plantation.,457.
MLA	He Q.-Y.,et al."Sap flow changes and climatic responses over multiple-year treatment of rainfall exclusion in a sub-humid black locust plantation".457(2020).