摘要
人工林草地土壤干化问题正在日益严重的威胁着黄土高原人工植被建设成效。利用2013年5月—2014年11月的定位监测0—900cm深层土壤水分资料分析得出:(1)研究区四种不同土地利用类型剖面土壤水分均表现出上层波动剧烈,下层变化较小的特征。上层土壤含水量具有与明显的季节性波动变化特征,代表当年降水的入渗深度,枣林、苜蓿草地、杏林和农地降水入渗深度范围分别为0—240,0—180,0—200和0—120cm。(2)深层土壤含水量年内变化较小,枣林、苜蓿草地和杏林土壤水分在根系吸水作用下有微弱减少,农地作物对深层土壤水分利用有限,得到降水补给土壤水分有所增加。土地利用方式对深层土壤水环境的影响大小依次为苜蓿草地>杏林>枣林>农地。(3)枣林、苜蓿草地和杏林深层土壤水分均存在一定的亏缺,苜蓿草地亏缺最为严重,平均亏缺度为67.7%,杏林和枣林平均亏缺度为55.4%和48.7%。深层土壤水分的变化规律能够反映长时段不同土地利用类型对土壤水分生态环境的深刻影响,对黄土高原植被的恢复、建设及评价具有重要意义。
In the Loess Hilly and Gully Region where climatic conditions are dry with severe water shortage, several plants causes soil dessication and ecological degradation. In order to compare the differences and char- acteristics of deep soil water under different land use patterns, relevant water moisture data in 0--900 cm soil layers was analyzed through May 2013 to November 2014. Results showed that： （1） the soil profile under different land use patterns could be divided into two layers according to the vertical variation. The upper con- tent changed dramatically, and the deep soil moisture was stable; the temporal variations of the upper soil water were accordance with the change of rainfall in the wet season, it represented the depths of rainfall infil- tration and plant-root water uptake, the depths of rainfall infiltration for jujube, almond, alfalfa and farm- land were 240, 200, 180 and 120 era, respectively; （2） soil water in deep layers changed little within a year, soil water contents of alfalfa grassland, jujub and almonds decreased slightly, however, crops had a shallow root system, utilization of deep layer soil water was limited; the water environment in deep soil layers was significantly affected by plant types, and the effect degrees decreased in the order： alfalfa grasslandS〉jujubeS〉almonds 〉farmland; （3） alfalfa grassland had led to the serious soil moisture deficit, the average degree was 67. 7%, and ju- jube and almonds were 55.4%, 48. 7%, respectively. It is vital to investigate temporal variability of deep soil mois-ture for the restoration, reconstruction and evaluation of vegetation in the Loess Plateau.
出处
《水土保持研究》
CSCD
北大核心
2016年第2期13-18,共6页
Research of Soil and Water Conservation
基金
林业公益性行业科研专项"山地红枣生态经济林增效关键技术研究与示范"(201404709)
关键词
黄土高原
土地利用
深层土壤水分
水分亏缺
I.oess Plateau
land use pattern
deep soil moisture
soil moisture deficit
