查询词典 desertification

Based on the GIS,RS,GPS and PRA,the impact of water resources on desertification and pauperization in the Minqin basin is studied.

以3S技术与PR A工具，通过对民勤盆地水资源状况的变化与沙漠化、贫困化发生发展规律对比研究，表明自然条件恶劣、基础设施弱是沙漠化、贫困化产生的内在因素，而人类活动则是强大的驱动力。

Wind-erosion is one of basic processes to mold the physiognomy landscape pattern and it is a process of desertification.

中文摘要：风蚀是塑造地貌景观格局的基本过程之一，也是土地荒漠化的一个过程。

External regulator of positive feedback is variation of precipitation amount and frequency of extreme precipitation. It is shown that desertification is predetermined by the decreased precipitation as well as by the decrease in frequency of precipitation. In the second half of 20th century importance of man-induced degradation of dry lands as additional regulator of positive feedback has been increased.

正反馈的外部调节因子是降水量的变化和极端降水事件的出现频率，降水量减少以及降水频率的降低直接影响沙漠化的程度。20世纪下半叶，人类因素导致的干旱土地退化作为另外的正反馈调节因子，其重要性正在增加。

Zhangye oasis as one of main producing area of commercial purveyance in China lies in the middle of Gansu corridor and is entitled "Golden Zhangye", But the district is circled by many dune and threaten by more and more serious desertification.

位于河西走廊中段的张掖绿洲作为我国的商品粮重镇，素有金张掖'的美称。然而在境内两大沙区数以万计的沙丘的分隔包围之下，该区又面临着严重的沙漠化威胁。

Desertification already accounts for a quarte(1/4) of the globe's land areas, and it expands at the rate of 50-70 thousand square miles per year.

全球荒漠化已占地球陆地面积1/4，在以每年5～7万平方公里的速度扩大。

It can be used as the guidance and reference in the application of PLC to robot.First, the fact of desertification and the prevention method were introduced generally and the importance and necessity of this research was also discussed. By comparing the characteristics and application field of SCM control system, relay control system and computer control system, we selected the control scheme based on PLC.

本文首先总体介绍了我国土地沙漠化的现状和防治方法，论述了该课题研究的重要性和紧迫性，并通过对比分析单片机控制系统、继电器控制系统、计算机控制系统各自的特点及应用范围，最后确定了基于可编程控制器为核心的控制方案。

This paper gives a research on desertification and its development trend in Maqu county, using the method of romote sensing and on-spot serveying.

作者运用遥感与地面调查相结合的方法，对玛曲县的土地沙漠化及其发展趋势进行了研究。

Land desertification is one of the most main types of land degradation in the arid and semiarid region,northern China.

土地沙漠化是我国北方干旱半干旱地区土地退化最严重的类型之一。

The social and economic sustainable development in the arid and semiarid area in China has been restricted by sandy desertification heavily.

沙漠化是制约我国干旱、半干旱地区社会经济可持续发展的重要因素。

The results show that:(1) wetland reservoirs can control wetland degeneration and springwater overflow;(2)wetland reservoirs can store floodwater and winter to prevent flood, drought and desertification so that keep ecological system balance of wetland;(3) uncoordinated contradiction between agricultural water use and ecological water demand can be resolved under the adjustable function of wetland reservoirs;(4)wetland reservoirs has effective capability to keep biological diversity.

对位于玛纳斯河流域泉水溢出带中的湿地水库群对流域生态环境的作用进行了研究，结果表明，该湿地水库群在防止湿地萎缩退化、防止次生盐渍化、保护流域内生物多样性、防风固沙、防止土壤沙化、抵御洪、旱灾害威胁、加强湿地调控能力以及增加了绿洲的人口承载能力和生产力等方面起到了很好的保护作用。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。