半干旱的

This study deals with precipitation fluctuations in the transitional zone between the arid and semiarid regions of northwest China from the 1950s to the 1990s,discusses spatial variation of 250 mm isohyet during the dry years and wet years; and systematically studies rainfall harvesting system relative to runoff inducing catchments, water storage and highly efficient utilization and evaluates the influence of rainwater harvesting on regional development and environment conservation.

分析了干旱半干旱区过渡带降水的时空变异性，确定了250 mm降水量线在丰枯年份的空间摆动幅度。

The conclusion show as followings: Based on parameter recension of EPIC model, the correlation coefficient between simulated alfalfa forage yield and root zone soil water with observed value were 0.8957 and 0.9884, the correlation coefficient between simulated A.

2半湿润区紫花苜蓿30年的水分生产潜力模拟值为4.262～13.456t/hm~2，根层有效水含量在第8年达到极低值，受土壤水分降低的影响，苜蓿的水分生产力水平开始降低，干旱胁迫日数开始加重，且分别与当年和前一年的降雨量成正相关和负相关变化。

Water shortage is an important factor that restricts food production in arid and semi- arid area in North China.

近年来，水分不足是限制我国北方干旱和半干旱区粮食生产的重要因子。

The measurement of water resources carrying capacity was an important guidance to the sustainable development of arid and semiarid area.

水资源承载力分析计算和评价是干旱半干旱区寻求区域可持续发展道路的重要依据。

Decadal variations of arid and semiarid boundary in China during last 100 years have been analyzed by using Thornthwaite's method.

利用Thornthwaite的干湿分类函数，对近100年中国干旱和半干旱区界限的10年际变动特征进行了分析。

In this thesis, we chose two wild rodents inhibiting in the north of China Mongolian gerbil (Meriones unguiculatus and Brandt's vole . The effects of short photoperiod and cold exposure to thermogenesis, and the mechanism of thermogenic regulation were studied. The new genes participating in cold adaptation were also screened by DDRT-PCR.

本文选择了华北地区的两种野生啮齿类（生活在内蒙古荒漠和半荒漠地区的优势鼠种长爪沙鼠和生活在内蒙古干旱草原的优势鼠种布氏田鼠）为研究对象，探讨光照对长爪沙鼠产热的影响，以及在低温因子作用下两种鼠适应性产热变化的机理，并利用差异显示技术试图寻找与冷适应性产热相关的基因。

The Rift Valley bisects the country above Nairobi, opening up to a broad arid plain in the north.

上述国家的裂谷成两半内罗毕开了广阔的北方平原干旱。

This research provides academic and instructive meanings for sustainable development of agriculture in semi-arid or arid irrigation region.

该研究对干旱半干旱区灌溉农业的可持续发展具有指导意义。

In natural vegetation area, where mainly are forest land, the yearly relative humidity and precipitation of spring are the driving forces to the change of NDVI. In brush and shrub area, the change of NDVI is driven by the precipitation and relative humidity of autumn. In grassland and rare tree bush grassland district, the main driving forces are human factors, and the driving mechanism is that farmland and cropping sown area are negative to the change of NDVI, but society factors are positive.

对于以林地为主的自然植被区植被覆盖变化，主要受到春季降水、春季湿度和年均湿度的正驱动，黄淮海地区的北部主要为干旱、半干旱区，因此春季降水偏多会利于植被生长；灌丛和萌生矮林区，秋季降水和秋季湿度对其植被NDVI变化呈负驱动；草原和稀树灌木草原区植被覆盖的变化，耕地面积、作物播种面积对之为负驱动，而其他社会经济因子则为正驱动。

This one mode pays close attention to network credence foundation of the businessman very much.

这一模式非常关注商人的网络信用基础。

Cell morphology of bacterial ghost of Pasteurella multocida was observed by scanning electron microscopy and inactivation ratio was estimated by CFU analysi.

扫描电镜观察多杀性巴氏杆菌细菌幽灵和菌落形成单位评价遗传灭活率。