摘要
为研究柠条锦鸡儿(Caragana microphylla)细根与土壤水分的空间关系,以内蒙古农牧交错带10 a生柠条锦鸡儿细根为研究对象,对细根表面积密度与土壤含水率之间的关系进行了初步探讨。分别对柠条锦鸡儿细根和土壤水分的空间分布情况进行研究发现,垂直和水平土层方向各标准地柠条锦鸡儿细根表面积密度与土壤含水率均呈极显著相关,相关系数均大于0.65(P<0.01)。经回归分析建立柠条锦鸡儿细根表面积密度与土壤含水率之间的关系模型并对模型进行验证,验证结果发现该模型可以很好地描述两者之间的关系(R^2=0.84,P<0.01)。撂荒地土壤含水率比柠条地高71%,研究区柠条地出现至少200 cm的土壤干层,部分土层接近凋萎湿度,柠条生长受阻。研究结果对于干旱区人工柠条林的栽植管理具有重要意义,可为北方农牧交错带生态环境建设及植被恢复提供理论依据。
The response of Caragana microphylla root system to soil moisture can reflect the growth status of the Caragana microphylla plantation.Most studies focus on the relationship between Caragana microphylla fine root and soil moisture distribution in the vertical profile.This study aimed to investigate the relationship between Caragana microphylla fine root and spatial distribution of soil moisture in Huanghuadianzi watershed（42°17＇-42°33＇N,119°36＇-119°53＇E）in Inner Mongolia.In August 2015,three sampling plots（150 m×150 m）were chosen in a s field with 10 a Caragana microphylla（density of2 m×4m）.The field had the slope gradient about 4°.A wasteland without Caragana microphylla was as a control.The average height of plant was 2.60,2.38 and 2.23 m for the 3 sampling plots.Fine root was collected from 0-200 cm soil depth for the determination of surface area density.Soil moisture was measured by a QS-SFY soil moisture measuring instrument.EPSON10000XL scanner and Win RHIZO root analyzing system were used for measurement of the fine root-related parameters.Meanwhile,the dried soil layer was investigated in the profile.The results showed that the fine root weight in the1-m soil depth accounted for 81%for the sampling plot 1,78%for the sampling plot 2 and 74%for the sampling plot 3 of the whole soil depth,respectively.The correlation between the soil moisture along the vertical and horizontal direction and the fine root surface area density was extremely significantly high with the correlation coefficient above 0.65（P〈0.01）.The spatial distribution of the fine root surface area density was consistent with that of soil moisture：the maximum value was right below of the sampling position and the minimum value was 50-70 cm.A model between fine root surface area density and soil moisture was built with R^2=0.74（P〈0.05）.After considering the spatial distribution of soil moisture,the model accuracy was improved to R^2=0.80（P〈0.05）.The validation of the modified model showed the R^2=0.84（P〈0.01）.It indicated that the fine root surface area density model considering the spatial distribution of soil moisture was reliable in predicting the fine root surface area density.The maximum field capacity and stable field capacity of the study area were 17.56%-22.01%and10.50%-13.77%,respectively.The soil moisture distribution of the 3 sampling plots was consistent.The soil moisture in the 3plots in the 200 cm depth was 3.47%-6.01%with a mean of 4.53%.The wasteland had the soil moisture of 5.10%-8.77%with a mean of 7.73%.The soil moisture of the wasteland was 71%higher than that of the sampling plot.There was at least a200-cm dried soil layer in the Caragana microphylla land and the soil drying was the most serious in the 70-cm depth below the soil surface.In the 70-cm soil depth,the soil moisture was even closer to the wilting soil moisture.The study provided an evidence that the land with a single Caragana microphylla could lower the soil moisture and hinder the plant growth.
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2017年第5期136-142,共7页
Transactions of the Chinese Society of Agricultural Engineering
基金
国家自然科学基金项目(31500584)
内蒙古应用研究与开发计划项目(20110732)
高等学校科学研究项目(NJZZ16055)
内蒙古自然科学基金项目(2016MS0407)
关键词
土壤含水率
根系
模型
细根表面积密度
柠条锦鸡儿
土壤干层
soil moisture
roots
models
fine root surface area density
Caragana microphylla
dried soil layer
