【正文】 d of time is limited primarily by the availability of areas of abundant rainfall well distributed through the year, all plants will transpire at about the same rates and the differences in total will result from the differences inthe length of the growing seasons for the various water supply is limited and seasonal, depth of roots bees very , shallowrooted grasses wilt and die when the surface soil bees dry while deeprooted trees and plants will continue to withdraw water from lower soil deeperrooted vegetation will transpire a greater amount of water in the course of a rate of transpiration is not materially reduced by decreases in soil moisture until the wilting point of the soil is 。在靜止的空氣中，氣壓差不久就變得較小，蒸發(fā)受水面水汽彌散速率的限制。蒸騰是植物將從土壤中吸收的水分以汽體的形式釋放到大氣中去的過(guò)程。在許多地方，無(wú)論地面水或地下水都已經(jīng)嚴(yán)重短缺了。如果缺水，就會(huì)使農(nóng)產(chǎn)品減產(chǎn)，就像缺乏鋼會(huì)引起汽車產(chǎn)量下降一樣。我們的農(nóng)產(chǎn)品，大部分都是由它構(gòu)成的。人可以接近兩個(gè)月不吃食物而仍能活著，但不喝水則只能活三四天。All life on earth depends upon water, the principal ingredient of living use of water by man, plants, and animals is it there can be no living thing requires can go nearly two months without food, but can live only three or four days without ，水是活細(xì)胞的基本組分（要素）。在水中，氧這種最豐富的化學(xué)元素與氫結(jié)合，其含量多達(dá)89%。雷電風(fēng)暴的形成，讓空氣溫度升高，然后上升到大氣。不止是這些造成了當(dāng)?shù)鼐用裉貏e是在發(fā)展中國(guó)家難以得到基本日常所需，還會(huì)導(dǎo)致外來(lái)者在土地市場(chǎng)和遷移這些對(duì)當(dāng)?shù)厝藢儆诮?jīng)濟(jì)侵略的領(lǐng)域處于支配地位。 home countries), and not to local businesses or addition, significant amounts of ine actually retained at destination level can leave again through ，利潤(rùn)，支出的工資以及進(jìn)口所需剩下的一部分，就是旅游目的地的直接收入，也叫做滲漏。土地合并項(xiàng)目經(jīng)常用于保護(hù)濕地，還有改變土地利用模式，特別是在因?yàn)轭l發(fā)的洪水和水土流失致使土地瀕臨消失的地方。土地合并的項(xiàng)目的重點(diǎn)已經(jīng)不再只關(guān)注農(nóng)業(yè)重組，它上升到通過(guò)平衡農(nóng)業(yè)利益，地形，自然保護(hù)，娛樂(lè)和運(yùn)輸(尤其是需要修建主要干道的時(shí)候)來(lái)獲取最大的利益。因此早期項(xiàng)目的總體目標(biāo)是通過(guò)增加產(chǎn)量和減少成本，以此增加從土地獲得的凈收益。what was good for the farmers was good for rural overall objective of early projects was thus to increase the net ine from land holdings by increasing the volume of production and decreasing its this focus on agricultural development, these projects served to consolidate parcels and enlarge holdings and included provisions such as irrigation and drainage infrastructure to improve water management, construction of rural roads, land levelling, soil improvement measures and changes to land use such as converting agriculturally inferior land into forest land or 。s primate city is Los Angeles, with a metropolitan area population of 16 million, which is more than double the San Francisco metropolitan area of 7 counties can be examined with regard to the Law of the Primate 。但是，并不是所有國(guó)家都有這樣一個(gè)首位城市，你可以從下面的表里看出來(lái)。數(shù)以萬(wàn)計(jì)的人民不得不背井離鄉(xiāng)。海岸侵蝕開始出現(xiàn)，尤其是在陡峭的海岸。經(jīng)歷這么大的變化曾經(jīng)需要數(shù)千年，但是現(xiàn)在只在近十年內(nèi)就完成了。世界上所有國(guó)家的人口金字塔在這里都可以找到。發(fā)展中國(guó)家的人口金字塔通常有很大的根基和很窄的塔尖。這時(shí)的水本質(zhì)上除了超過(guò)100攝氏度的情況是不可移動(dòng)的。所以這些過(guò)程都發(fā)生在表面。下完雨之后，滲透會(huì)形成一個(gè)土壤完全充滿水的情況。灌溉可以給作物提供附加的水。通常情況下，下面四個(gè)因素影響了這兩個(gè)過(guò)程：可利用的能量、蒸發(fā)表面的溫度梯度、蒸發(fā)表面即時(shí)風(fēng)速、可用的水。蒸發(fā)是空余的水變成蒸汽進(jìn)入大氣的移動(dòng)過(guò)程。41頁(yè)Evaporation and transpiration are the two processes that move water from the Earth’s surface to its is movement of free water to the atmosphere as a requires large amounts of is the movement of water through a plant to the use the term evapotranspiration to describe both general, the following four factors control the amount of water entering the atmosphere via these two processes: energy availability。The distribution of precipitation on the Earth39。Parent material refers to the rock and mineral materials from which the soils materials can be derived from residual sediment due to the weathering of bedrock or from sediment transported into an area by way of the erosive forces of wind, water, or is often faster on transported sediments because the weathering of parent material usually takes a long period of influence of parent material on pedogenesis is usually related to soil texture, soil chemistry, and nutrient 。在平衡條件下，植被和土壤通過(guò)彼此的養(yǎng)分循環(huán)緊密聯(lián)系在一起。如果降水少于蒸發(fā)作用，土壤的濕度就會(huì)變低。溫度越高，基巖轉(zhuǎn)化為礦物顆粒的比例越大。在區(qū)域和地方性的范圍內(nèi)，氣候顯得不是那么重要。從全球尺度來(lái)看，主要的土壤分類和科彭氣候分類法確定的主要的氣候類型有明星的聯(lián)系。溫度直接影響基巖風(fēng)化產(chǎn)生礦物顆粒。如果降水超過(guò)蒸發(fā)作用消耗的水，土壤濕度就會(huì)很高。Living organisms have a role in a number of processes involved in pedogenesis including organic matter accumulation, profile mixing, and biogeochemical nutrient equilibrium conditions, vegetation and soil are closely linked with each other through nutrient cycling of nitrogen and carbon in soils is almost pletely controlled by the presence of animals and litterfall and the process of deposition, organisms add humus and nutrients to the soil which influences soil structure and vegetation also protects the upper layers of a soil from erosion by way of binding the soils surface and reducing the speed of moving wind and water across the ground ，生命體參與了其中的有機(jī)物積累，屬性混合和生物化學(xué)養(yǎng)分的循環(huán)。表層植物也可以固定表層土壤來(lái)保護(hù)上層的土壤不被途經(jīng)的風(fēng)和水帶走。母質(zhì)在成土過(guò)程中的影響就是它參與了土壤的質(zhì)地，土壤化學(xué)和養(yǎng)分循環(huán)。下面的一組數(shù)字將闡明全球降水模式。and water scientists sometimes refer to two types of evapotranspiration: Actual Evapotranspiration and Potential growth of crops is a function of water crops experience drought, yields are can supply crops with supplemental determining both actual evapotranspiration and potential evapotranspiration a farmer can calculate the irrigation water needs of their ?？茖W(xué)家用蒸散作用來(lái)統(tǒng)稱這兩個(gè)過(guò)程。如果作物經(jīng)歷了干旱，就會(huì)導(dǎo)致減產(chǎn)。滲透由于一些自然的因素會(huì)發(fā)生空間的和暫時(shí)的變化。土地含水能力展示給我們一個(gè)水薄膜，在這個(gè)薄膜里。水就停止流失。這些信息展示出了一個(gè)年齡性別或者人口數(shù)量的金字塔。塔尖由于死亡的原因會(huì)稍微窄一些。因?yàn)榛剂系娜紵?，大地沒(méi)有植被以及農(nóng)業(yè)，大氣中二氧化碳和其他溫室氣體的排放量已經(jīng)上升了1/3。由于很多城市坐落在沿海地區(qū)，這就可能帶來(lái)災(zāi)難性的問(wèn)題。另一個(gè)嚴(yán)重的問(wèn)題是鹽水侵入沿海地區(qū)的底下淡水。他們的規(guī)模大小和活動(dòng)變成一股強(qiáng)大的推動(dòng)力，帶來(lái)額外的居民，讓這些首位城市變得更大，以至于跟國(guó)內(nèi)的其他小城市相比有些不協(xié)調(diào)。The law can be applied to smaller regions as example, California39。69頁(yè)Scope of land consolidation schemes（本段藍(lán)字為不確定部分）Land consolidation has always been regarded as an instrument or entry point for rural concepts of rural development were virtually the same as agricultural development because of the predominant role of agriculture in rural areas at the the agrarian structure was viewed as being identical to maintaining the social viability in rural areas。對(duì)農(nóng)民好也就是對(duì)農(nóng)村地區(qū)好。農(nóng)村發(fā)展的概念已經(jīng)變得更加廣闊，已經(jīng)拓展到包含環(huán)境意識(shí)和非農(nóng)業(yè)應(yīng)用的領(lǐng)域。水體被修復(fù)，一般都還有緩沖區(qū)。 expenditures go to the airlines, hotels and other international panies(who often have their headquarters in the travelers39。101頁(yè)Tourism development and the related rise in real estate demand may dramatically increase building