Naoli River Basin is an important food supply base in China.With the development of agricultural modernization and the increasing of fertilizer using,the nitrogen concentration in groundwater is increasing year by year.Characteristics of spatial distribution of the three nitrogen pollution in the area and its variation with time,the relationship between the concentration of the three nitrogen and its causes were analyzed based on the monitor data of groundwater quality from 2011 to 2013.The results showed that the three nitrogen contaminated areas of Naoli River Basin were mainly distributed in areas where agricultural activities were more active and they were also influenced by groundwater runoff conditions;the three nitrogen concentration in groundwater of the study area was higher in wet season than that in dry season.In addition,the correlation of pollution trends between ammonia nitrogen and nitrate nitrogen in groundwater was influenced by the unsaturated zone thickness.

Based on Nalinggele River Catchment in Qaidam Basin,the large-scale groundwater numerical modeling method was discussed to improve the model reliability.By means of two-dimensional groundwater flow of typical hydrogeological profile in Nalinggele River Catchment,the groundwater flow systems were divided into shallow,middle-deep and deep groundwater flow systems.Referencing the scope of the key study area and the middle-deep groundwater flow system,a regional three-dimensional groundwater flow model was established in a relative complete hydro-geological unit.Constrained by the regional groundwater modeling results,the groundwater modeling of the key study area was established and the hydrogeological parameters were recognized further to improve the modeling reliability.

The slag debris flow is a typical representative of the debris flow,as is obviously different from the natural debris flow.Slag debris flow disaster in our country ,connected with the developments of the exploitation , makes it become one of the most dangerous geological disasters.This paper is aimed at the analysis of its stability through the investigations of the basic situation in the area,combining with the characteristics of the slag debris flow.The layer characteristics and particle size is in distribution.It shows that the high water permeability and instability are the key factors of the start in slag debris flow to provide some basic theoretical basis for the monitoring and prediction of debris flow in future.

Wastewater irrigation can save water resources to a certain extent,but irrational utilization of wastewater can also cause pollution of groundwater.This paper reviews such an issue caused by wastewater irrigation in different cases,which is normally identified as increasing nitrate,hardness,heavy metals,pathogenic microbes,and organic compounds in groundwater.The mechanisms of migration and natural attenuation of pollutants are discussed,and the factors influencing the transport and transformation of contaminants in vadose zone are also examined.Subsequently,the measures to prevent the side effects of wastewater irrigation and the further studies on these topics were proposed.

泥化夹层的分布及强度不仅影响到库区两岸山体的稳定,而且还影响到坝基的稳定.在大量地质勘探试验研究资料的基础上,研究了索达干坝址区泥化夹层的类型及分布规律、泥化夹层的粒度成分及物理性质,分析了不同试验方法对泥化夹层抗剪强度的影响,提出了抗剪强度指标的建议值.

冻土的存在，不仅会对建于该区的建筑物造成危害，而且还可能引起塌滑、泥(石)流、地面融陷等不良地质现象。本文从分析影响冻土发育的因素入手，分析了调水区的冻土类型和分布规律，以及冻土的构造及工程地质特征。最后简单地预测了冻土的演化趋势。