坡面过程意义下的武汉市典型坡面土层厚度研究

坡面系统对坡面成土过程和搬运过程有着重要影响,土层厚度在坡面上的空间分布规律能够一定程度上反映坡面过程.该文在区域线路调查的基础上,实地测制武汉市4座典型山地的8条典型坡面,布设36个采样点,并结合遥感影像,调查了其土层厚度的分布特征及坡面系统各要素,结果表明：1)各条坡面总体呈现土层厚度由坡底到坡顶递减的分布规律;2)母质岩性是坡面成土过程所形成土层厚度的主要影响因素;3)坡度和坡长是坡面搬运过程的主要影响因素.     

Estimation of wind erosion rates by using 137Cs tracing technique: A case study in Tariat-Xilin Gol transect, Mongolian Plateau

Wind erosion is one of the major environmental problems in semi-arid and arid regions. Here we established the Tariat-Xilin Gol transect from northwest to southeast across the Mongolian Plateau, and selected seven sampling sites along the transect. We then estimated the soil wind erosion rates by using the 137Cs tracing technique and examined their spatial dynamics. Our results showed that the 137Cs inventories of sampling sites ranged from 265.63=44.91 to 1279.54=166.53 Bq. m-2, and the wind erosion rates varied from 64.58 to 419.63 t. km-2. a-~ accordingly. In the Mongolia section of the transect （from Tariat to Sainshand）, the wind erosion rate increased gradually with vegetation type and climatic regimes; the wind erosion process was controlled by physical factors such as annual precipitation and vegetation coverage, etc., and the impact of human activities was negligible. While in the China section of the transect （Inner Mongolia）, the wind erosion rates of Xilin Hot and Zhengxiangbai Banner were thrice as much as those of Bayannur of Mongolia, although these three sites were all dominated by typical steppe. Besides the physical factors, higher population density and livestock carrying level should be responsible for the higher wind erosion rates in these two regions of Inner Mongolia.     

Using 137Cs tracing technique to estimate wind erosion rates in the typical steppe region,northern Mongolian Plateau

Wind erosion is one of the major factors of land degradation in the typical steppe region, northern Mongolian Plateau. Using ^137Cs tracing technique, we estimated the wind erosion rates of different pastures and abandoned farmland at Bayannur and Karakorum in Mongolia. The pastures and cutting grassland at Bayannur were slightly eroded by wind, with the rates of 64.58-169.07 t·km^-2.a^-1. The abandoned farmland in Karakorum, however, was strongly eroded by wind, with annual surface soil loss of 4.05 mm. a^-1, and wind erosion rates up to 6723.06 t· km^-2. a^-1. The total loss of surface soil due to wind erosion has been 17.4 cm since the cultivation of the steppe land in the 1960s. The wind ero- sion rate at the abandoned farmland was much higher than that at the typical steppe sites, showing that the cultivation led to serious wind erosion in the typical steppe region, northern Mongolian Plateau. By contrast, traditional livestock grazing resulted in less disturbance to the surface soil, and did not induce to devastating wind erosion, which plays an important role in maintaining the stability of the steppe ecosystem in the northern Mongolian Plateau.     

黄河的综合治理方略

黄河是我国第二长河,为西北和华北地区提供了丰富的水资源、黄河灾害频繁,是世界上最难治理的河流．经过几千年的治理,黄河已经成了一条人工控制的河流．然而,黄河仍然面临侵蚀严重、河床不稳定、水体污染以及生态脆弱等诸多问题．笔者依据河流综合治理的原则,为达到“维持黄河健康生命”的目标,提出了控制沟道下切、增阻降速、建设通河湖泊湿地和控制点源污染等综合治理方略、     

Dynamic study on water stability of soil structure and soil characteristics of several types of soils in southwest China

Three suborder soils in southwest China were adopted, namely Ustic Vertisol, Stagnic Anthrosol and Ustic Ferrosol, so as to carry out the basic physical and chemical analysis respectively, to design a dynamic measuring method for water stability of soil structure and conduct the comparative study on the quality of the soil structure. The results indicated that （1） The water stability dynamic characteristic of the soil structure could well reflect the maintaining capability of the soil structure as time goes on. （2） The quality of several soil structures in southwest China was sequenced as follows： Stagnic Anthrosols 〉 Ustic Vertisols 〉 Ustic Ferrosols. （3） The water stability of soil structure is very positively correlated with the capillary porosity and the clay particle （D 〈 0.002 mm） content （Co）, but is very negatively correlated with the silt （D is 0.05-0.002 ram） content （Csc）, and （4） The dynamic functional equation of the water stability of soil structure in southwest China was established, so that the water stability characteristics of various soil structures could be quantitatively expressed and the quality of different soil structures can be quantitatively compared from each other.     

西藏高原当前生态环境问题的初步研究

文章从西藏高原的各种侵蚀类型分别阐述其所带来的相应的生态问题以及形成的原因。西藏高原由于地理条件的特殊性,它的生态问题也拥有自己的特点：脆弱性、难恢复性。在制定保护措施、恢复方法方面还要具有针对性,同时,要考虑到人们的行为在此过程中所扮演的角色。     

考虑管径拓展的管涌发展过程模拟

堤基管涌发展试验表明,在管涌通道发展过程中,通常是上游管径较小而下游管径较大,管道尖端土体颗粒比较松散.现有的堤基管涌发展模型采取单一管径处理方法模拟管涌通道发展过程,管涌发展过程中孔隙率保持不变,难以模拟通道侧向扩展特征.本文采用泥沙运动力学方法,考虑通道发展过程中的颗粒级配调整和孔隙率变化,使得管涌通道发展情况更加符合实际.数值模拟表明,改进后的模型能够刻画管涌通道发展中的管径变化、通道发展方向、流量大小和临界水头等主要特征.     

蒙药哈它嘎其-7治疗宫颈糜烂效果观察

目的：探讨蒙药哈它嘎其-7治疗宫颈糜烂（CE）的临床疗效.方法：选择宫颈糜烂患者52例,病程3个月以上,曾用西药或中药治疗而未用过蒙药者,给予外用蒙药观察疗效.结果：外用蒙药治疗有效率达94.2%.结论：蒙药治疗宫颈糜烂治愈率高,复发率明显降低,副作用小,价格低廉,值得更多的临床医生了解并在临床中推广应用.     

基于突变理论的路基边坡冲刷稳定性评价

采用一种结合模糊数学和突变理论的新方法,评价路基边坡在降雨条件下的冲刷稳定性,在充分利用现场监测数据的基础上,建立边坡冲刷稳定性的综合评价体系。为避免人为确定评价因素权重的主观性,将突变理论运用于边坡综合评价中进行多准则评价决策。选取底层评价指标并根据隶属函数进行标准化计算,运用突变模型中的归一化公式得出边坡冲刷的总突变值,进而实现对边坡安全稳定性的评判。最后通过工程实例进行了分析验证。结果表明,该评价方法结合了模糊数学和突变理论的优点,能有效减少评价因素权重确定的人为主观性。     

代数格上形态算子的表示方法

以二值形态运算中平移变换的作用为引导,赋予代数格上的自同构群可交换的特性,使得形态算子的表示更为明确.在此基础上研究了代数格上形态算子的表示定理,并将这种思想运用于Matheron二值形态算子表示定理与极小内核表示定理的证明中.