半沙漠

At the South Edge of the Tengger Desert, the sampled sites of mobile sanddune, semi-fixed sand-dune and fixed sanddune were selected as the different stages of the reversion process of desertification with the method of substituting time with space, and topsoil mineral elements of the decertified land were studied reversion process of desertification.

以腾格里沙漠南缘沙漠化土地为研究对象，应用时空替代法选择流动沙丘、半固定沙丘、固定沙丘的沙漠化逆转序列样地，研究了沙漠化逆转过程土壤矿质元素的变化特征。

But shooting the sun is tricky. On a clear day, the sun is so bright that your camera's meter will tend to underexpose everything else in the frame. Shoot in manual mode, or take a reading without the sun in frame, depressing the shutter button halfway to hold the exposure, then reframe before you shoot. If you're shooting film, bracket a lot to make sure of getting the exposure you want.

把太阳放在构图中以表达沙漠中的高温和荒芜，但拍摄太阳比较麻烦，晴空下的阳光影响相机的感光计，以至于构图中其它部分曝光不足，为避免这种情况，要启用相机的手动模式，或者是将太阳从构图中排除后，半按下快门固定曝光值，然后重新选择有太阳的构图，将快门按到底。

Think about including the sun in your photograph—it's one sure way to say hot and harsh. But shooting the sun is tricky. On a clear day, the sun is so bright that your camera's meter will tend to underexpose everything else in the frame. Shoot in manual mode, or take a reading without the sun in frame, depressing the shutter button halfway to hold the exposure, then reframe before you shoot.

把太阳放在构图中以表达沙漠中的高温和荒芜，但拍摄太阳比较麻烦，晴空下的阳光影响相机的感光计，以至于构图中其它部分曝光不足，为避免这种情况，要启用相机的手动模式，或者是将太阳从构图中排除后，半按下快门固定曝光值，然后重新选择有太阳的构图，将快门按到底。

First of all,we tested the germination and water uptake rate of 47 species typical xerophil seeds grow up in north China from 20 families,38 genuses under sufficient water and different Grads water stress by high-molecular-weight polyethylene glycol(PEG6000).The results show that Xerophil seeds from the same habitat exhibited similar patterns in response to water stress.Xerophil seeds from arid community were stronger in germination and imbibition than that from other two communities under serious water stress,whereas Xerophil seeds from humid community were sensitive to any degree of water stress.Namely,the seeds live in arid habitat possessed high germination and quickly water uptake in sufficient water or any degree of water stress,but the others grow up in humid habitat shown significant difference which germination and water uptake well under sufficient water but inhibited even if slight water stress.

首先，我们通过对20个科，38属，47种旱生植物种子在水分充足和不同梯度的干旱处理(聚乙二醇PEG6000)条件下的萌发率及吸水率实验发现，当水分胁迫强烈时，分布于干旱沙漠地区的植物种子其吸水率和萌发率都高于半干旱和湿润地区的植物群落，相反，湿润地区植物种子的吸水率和萌发率对任何的水分胁迫都表现出敏感的响应趋势，也就是说，生境恶劣的植物种子在较强的干旱胁迫下，仍然保持了较高较快的萌发率及吸水率，水分充足与水分缺乏时无显著差异，而生境相对较好的植物种子在水分充足情况下萌发与吸水良好，但在干旱胁迫时则受到明显抑制，水分充足与水分缺乏时差异显著。

The Sahara divides the continent into North and Sub-Saharan Africa . These two regions are culturally and climatically distinct. The southern border of the Sahara is marked by a band of semiarid savanna called the Sahel ; south of the Sahel lies the lusher Sudan .

撒哈拉沙漠将非洲大陆分割成两部分，北非和南部黑非洲，这两部分的气候和文化截然不同，撒哈拉沙漠南部边界是半干旱的热带稀树草原，阿拉伯语称为&萨赫勒&，再往南就是雨水充沛，植物繁茂的南部非洲，阿拉伯语称为&苏丹&，意思是黑非洲。

Our country's deserts mainly lie in arid and semiarid areas, mostly with scarce precipitation and lack of water resource, neither natural vegetation with relatively strong drought-resistance capability nor plantation, like diversifolious poplar, dryland willow, shrubby sand willow, saxoul and Hedysarum mongolicum Turcz,etc., can be protected effectively, this leads to desertification area expansion and frequent sand storm, which seriously affect people's work and life.

我国沙漠多处于干旱和半干旱地区，绝大部分地区降水稀少，水资源缺乏，无论是具有较强抗旱能力的天然植被，还是人造林如胡杨、旱柳，灌木类沙柳、梭梭、杨柴等都得不到有效保护，导致沙化面积扩大，沙尘暴发生频繁，给人民群众的生产生活带来严重影响。

On the basis of investigation data collected from 20 plots of the fixed dunes and the semi-fixed dunes in Wulanbuhe desert characteristics of species diversity and spatial distribution pattern of Hedysarum scoparium population were investigated.

根据乌兰布和沙漠固定沙丘和半固定沙丘20个样方的调查数据，对不同生境中花棒群落物种多样性及其种群空间分布格局进行了研究。

In this study, with the psammophilous Caragana Korshinskii-Artemisia ordosica communities on semifixed dunes and fixed dunes in Shapotou region at the southeastern fringe of the Tengger Desert as the observation sample plots, the survey quadrats were arranged in the vegetation community areas with different types and coverages of soil microbiotic crusts.

本文以腾格里沙漠东南缘的沙坡头地区半固定沙丘柠条一油蒿群落和固定沙丘柠条一油蒿群落为观测样地，选择具有不同类型生物土壤结皮分布的植被群落为观测样方。

In this study,with the psammophilous Caragana Korshinskii-Artemisia ordosica communities on semifixed dunes and fixed dunes in Shapotou region at the southeastern fringe of the Tengger Desert .

本文以腾格里沙漠东南缘的沙坡头地区半固定沙丘柠条-油蒿群落和固定沙丘柠条-油蒿群落为观测样地，选择具有不同类型生物土壤结皮分布的植被群落为观测样方。

The Hodotermitidae are a semi-desert species known as forage bants.

草白蚁科常称为草料蚁，是一种半沙漠种。

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。