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water table 1.【建筑】承雨線腳;瀉水臺。2.【地質學;地理學】潛水...

water tank

For example , at pore - water pressures of zero and greater , ( i . e . below the water table ) , there is a saturated conductivity value ; at pore - water pressures less than zero , ( i . e . above the water table ) , the hydraulic conductivity is zero 比如:當孔隙水壓力大于等于0 (如位于水位以下) ,有一個飽和的導水值;當小于0時(如在水位以上) ,導水性為0 。

The spatial and temporal distribution of water resource is the dominant factor that influences the dynamic of ground water . the influence displays mainly in the seasonal and spatial dynamic of ground water table and water quality 水資源在時空上的分配是地下水動態的主要影響因素,主要表現在地下水位、水質在季節和空間上的動態變化。

The job of agricultural drainage is to accelerate removing of the excessive water and salt in soil , control the underground water table at favourable depth , so that it can assure crops growing well and avoid salinization 農田排降任務是加速排除土壤中過量的水分及鹽分,控制地下水位在適宜的深度,保證作物的正常生長及防止土壤返鹽。

Assessment of site conditions is necessary to ascertain suitability for the mf method . these include geological conditions , underground water table levels and overlying soil thickness , and all other relevant factors (六)多圓形潛盾隧道之施工條件探討,對多圓形潛盾隧道工法之適用地質、覆土深度及其他限制條件需一并考量。

Furthermore because of low water table , the high salinity of the field is now serious . after years of development and renovation , it is now a center for agriculture , industry , and economy in ningxia province 灌區經過幾十年的發展和改造,現已成為寧夏農業和工業經濟中心,但長期以來水資源的問題還沒有得到完全解決。

The results of correlation comprehensive array analysis indicated that the water seepage from canal systems was the main cause resulting in the uprising of underground water table and the increase of soil salinity in qyrid 同時通過關聯度綜合排序分析,確定出渠系滲漏是造成灌區地下水位高、土壤鹽漬化的主要原因。

The main contents are as follows : ( 1 ) based on the fundamental seepage theory , the all - around effect of water table by rain infiltration are discussed with the equivalent infiltration intensity method 主要內容如下: ( 1 )從滲流基本理論出發,用等效入滲強度法來探討降雨入滲對地下水位影響的綜合效應。

Our aquifers are draining faster than they can be replenished , and the biggest , ogallala , which stretches from south dakota to texas , has seen localized drops in the water table of 150 feet 我們的地下水使用比注入得更快并且更多,從南達科他州延伸到德克薩斯州的奧加拉拉的水量下降到150英尺。

During the growing season , the ground water tables at each sampling point are falling , but the total salinity of the soil does not change much 這是因為180 240cm以上土層是根系大量分布的層次,群落中的植物均以鹽生植物為主,它們在生長過程中能夠吸收土壤中的大量鹽分離子而保持正常生長。

The calculation result effectively indicate the change rule with the time and space of water table of the aquifer , soft dank aquifer , parameter in process of wells work in the pit 計算成果較好地刻畫了基坑井群的實施過程中含水層、弱透水層水頭、參數的時空變化規律。

2 . the change of water content and salt concentration in soil is a dynamic process of balanced accumulation and consumption . it is influenced markedly by the ground water table 而180 《 40cm以下土層主要受地下水的水位、水質影響,因為地下水的總鹽含量變化也較小。

Therefore , the spatial and temporal dynamic of the soil water and salinity , the ground water table and salt concentration are main factors affecting the oasis stability 因此,干旱區流域內土壤水鹽和地下水水位、鹽分含量的動態變化成為影響綠洲穩定性的重要因素。

In addition , the significance of the disaster causal critical water table to preventing land subsidence disaster and exploiting groundwater resource reasonably is also analyzed 分析了地面沉降成災臨界水位對預防地面沉降災害發生及合理開采地下水資源的重要意義。

Based on the previous research , the concept of “ disaster causal critical water table “ and its general identification method are propounded for the first time 摘要在分析以往研究不足的基礎上,首次提出了地面沉降成災臨界水位的概念及一般確定方法。

So overuse of groundwater , mainly for irrigation , lowers the water tables , allowing air to reach the contaminated clay and release the arsenic 所以過度取用地下水(主要用于灌溉)降低了地下水位,使空氣得以接觸有毒黏土而釋放出砷。

“ the water table is so high at the moment that even small amounts of rainfall could lead to local flooding , “ a met ireann spokesman said “國家氣象局的一位發言人說: “這個時刻水位這么高,小小的降雨量也可以導致局部洪水。 ”

Global warming shall continue to melt the ice caps and glaciers causing the water tables to rise , and flooding certain regions of your continents 全球變暖將繼續融化冰山和冰蓋,導致水域增長并淹沒你們大陸的某些地區。

They are moderately well drained with a fluctuating water table and contain low amounts of organic matter , phosphorus and potassium and 受地下水位波動影響,土壤排水程度中等,有機質、磷和鉀含量低(表2 、 3 ) 。

Appropriate scheduling for efficient irrigation and measures for controll ing water table will be the keys to the answer to the problems 合理的灌溉方式和地下水位的有效控制將是解決問題的關鍵。