( 4 ) water - soil curing and using techniques of large opencast coal mine within loess area in our country have been divided into three types : water - soil safety techniques , water - soil conservation and water - soil recycling use techniques ( 4 )明确将我国黄土区大型露天谋矿水土整治和利用技术划分为水土安全调控、表层岩土水土保持和水土资源化利用三个阶段
Based on rainfall and evaporation amount , the change of soil water could be divided into three main periods , such as decreasing of soil water storage in spring , alternatively decreasing and increasing in summer and autumn , and relatively stable in winter 根陈洪松博士学位论文:黄土区坡地土壤水分运动与转化试验研究据年内降雨和水面蒸发量的相对大小，可将土壤水分的变化分为三个主要时期:春季失墒期、夏秋增失交替期和冬季相对稳定期。
This paper systematkally researched the characteristics of growth and physiology of sophora viciifolia hance ( a kind of natural shrub ) and its effects on the content of soil water , soil nutrieftt and soil physical property . the paper applied some methods and theory of plant ecology , plant physiology , physics of soil and soil chemistry etc . three different age s . viciifolia hance in the different plot were selected , caraganar land and fallow land as a comparison 本文以陕北黄土区安塞纸坊沟流域内在植被演替中占有重要地位的天然灌木种( 6 、 14 、 17龄)狼牙刺( sopharaviciifoliahance )为对象，以15龄柠条( caraganar )和撂荒地为对照，系统研究了狼牙刺的生长特征、生理特性，及其生长对土壤水分、土壤养分、土壤物理性状的影响。
In view of the natural conditions in loess area of gansu , in the light of investigation conditions of seepage of built loess and weak rock highway tunnels in this area and classification of water gushing conditions for railway tunnels , and by engineering analogism , the classification of tunnel water gushing types suited the structure design of highway tunnel waterproof and drainage , and the three methods for checking and subdividing water gushing types are presented 摘要针对甘肃黄土区的自然条件，依据该地区已建黄土及软岩公路隧道渗漏水调查情况和铁路随道涌水状态分类，运用工程类比法提出适合该地区公路隧道防排水结构设计的隧道涌水类型划分及对涌水类型校核与细分的三种方法。
This research object is the biology water protecting measures of the antaibao surface opencast coal mine ( atb ) south stackpile within loess area , including 4 aspects as below : ( 1 ) the form and distribution characteristics of erosion in original and newly - constructed lands of the atb south stackpile . the original water erosion modulus is 3700 ~ 4400t / km ~ ( 2 ) a in the south stackpile 本研究以我国黄土区安太堡大型露天煤矿南排土场为对象，以生物水土保持措施为研究角度，研究内容包括以下4个方面： ( 1 )安太堡矿南排土场原地貌的水蚀特征和排土场新造地土壤侵蚀的形式与分布特征。
This desertification is not only resulted in the changes of the land ' s type , the destruction of the vegetation and the erosion of the soil is aggravated in the local area , but also causes the frequency and the affective scope of the sandstorm enlarges and aggravates the erosion of the soil and the rate of schlepping sand with the rate of schlepping sand with the river in the adjacent loess areas 此种现象不仅造成本地区土地类型改变、植被摧毁和土壤侵蚀加重等，也引起毗邻地区沙尘暴频率和影响范围增大、加重黄土区土壤侵蚀及河流粗沙输沙率等荒漠化效应。
