Spatial Variability of Soil Saturated Hydraulic Conductivity in a Small Watershed of Loess Hilly Reg

来源 :Chinese Forestry Science and Technology | 被引量 : 0次 | 上传用户:sclin
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
Saturated hydraulic conductivity (Ks) is an important soil hydraulic parameter for charactering the rate of water flow across the soils and is mainly related to its high spatial variability. In a small watershed with the area of 0.27 km2 in the Loess Plateau, Ks of 197 soil samples under different vegetations and landforms were measured. Ks had a moderate variability for total samples. The forestland had high Ks with low coefficient of variation (CV), but the grassland in the watershed bottom had low Ks with big CV. Ks had moderate correlation in space distribution and combined both structural and random factors. At the N-S and E-W directions of watershed being parallel and normal to the stream valley, Ks had relatively weak correlation, indicating that the random factor was the dominate reason causing spatial variance. At the NE-SW and SE-NW directions, Ks had relatively strong correlation due to structural factors such as geomorphology and vegetation distribution patterns. Kriging optimal estimation method was used to produce Ks contour map. The Kriging standard deviation (SD) was the lowest near the sampling points, and increased along with the distance to sampling points. In the Loess Plateau region, soil texture is relatively even, and the vegetation distribution pattern was the key factor affecting spatial variability of Ks. Saturated hydraulic conductivity (Ks) is an important soil hydraulic parameter for charactering the rate of water flow across the soils and is mainly related to its high spatial variability. In a small watershed with the area of ​​0.27 km2 in the Loess Plateau, Ks of 197 Ks had a moderate variability for total samples. The forestland had high Ks with low coefficient of variation (CV), but the grassland in the watershed bottom had Ks with big CV. Ks had moderate correlation in space distribution and combined both structural and random factors. At the NS and EW directions of watershed being parallel and normal to the stream valley, Ks had relatively weak correlation, indicating that the random factor was the dominate reason causing spatial variance. At the NE-SW and SE-NW directions, Ks did relatively strong correlation due to structural factors such as geomorphology and vegetation distribution patterns. Kriging op The Kriging standard deviation (SD) was the lowest lowest of the sampling points, and increased along with the distance to sampling points. In the Loess Plateau region, soil texture is relatively even, and the vegetation distribution pattern was the key factor affecting spatial variability of Ks.
其他文献
高三频繁的考试只是一种查漏补缺的手段,可是有的同学因此变得十分脆弱。某中学的高三学生林宁就遇到了这个问题,他这样介绍自己的情况:高三一个学期没过完,我考试的卷子就足
目前中小学校舍档案管理工作仍然是一个十分薄弱的环节,主管部门、学校重视程度不高、管理职能分散、管理力量薄弱、管理基础不够规范、历史资料缺失、管理手段落后,已经影响
根据10个梁高不等钢筋混凝土框架中节点试件在低周反复荷载作用下的试验结果,重点分析了该类框架中节点的破坏过程和破坏特点。在试验研究的基础上,通过建立平衡方程、运动方
情感是教育中不可或缺的重要组成部分。而语文课程中蕴含着丰富的思想感情,升华这些感情不仅是高中语文课程教学的目的,也是培养学生综合素质发展的重要途径。因此在高中语文
读幼儿园大班时,我学会了下五子棋。每天晚饭后我总要缠着妈妈下棋。哈哈,想不到吧,每次下棋我都能赢,不是我的棋艺好,而是我有“绝招”。一天晚上,我和妈妈下棋,我眼睛盯着
期刊
目前的中职学校学生普遍存在口语表达能力较差的情况。本文结合语文教学的实践,从四方面谈论如何提高中职学生口语表达能力的体会。 At present, secondary vocational scho
我的家乡攀枝花(pān zhī huā)是个钢铁工业城市,因此,她也被人们称为“钢城”。这里矿(kuànɡ)产丰富、风景优美,但我最喜欢的还是“钢城”的夜景。  每当夜幕降临(jiànɡ lín)的时候,五颜六色的灯光就开始争先恐(kǒnɡ)后地炫耀  (xuàn yào)自己的美丽了。不一会儿,灯火辉煌(huī huánɡ)的“钢城”就成了一片灯的海洋、光的世界。厂房里闪耀(shǎn yào)的
期刊
笔尖在纸上轻轻地滑动着,黑白分明的线条在纸上飞舞。我想飞,和线条一起飞,一抹淡淡的微笑挂在了脸上。看着纸上一个个惟妙惟肖的人物,或微笑,或冷漠,这个腹黑,那个冰山,我突
由于天然砂资源的匮乏,人工砂作为一种较为理想和实际的替代材料,正被越来越广泛地应用于各种工程建筑中。近年来国内相继出现了以山砂、石屑等替代天然河砂。在实际工程中应
目的:观察自拟治衄汤配合鼻内镜下微波热凝治疗鼻衄的临床疗效。方法:将150例鼻衄患者随机分为2组,治疗组76例采用鼻内镜下微波热凝出血点并间断多点热凝周边充血区或裸露的