VOA慢速英語(yǔ):Building a Windbreak to Protect Crops

From VOA Learning English, this is the Agriculture Report.

這里是美國(guó)之音慢速英語(yǔ)農(nóng)業(yè)報(bào)道。

Soil conservation methods help farmers protect their land from the damage caused by farming and the forces of nature. One method of soil conservation is the use of windbreaks. Windbreaks are barriers formed by trees and other plants. Farmers plant these barriers around their fields.

各種土壤保護(hù)的辦法可以幫助農(nóng)民防止其土地受到耕作和大自然力量的損害。土壤保護(hù)的辦法之一是采用防風(fēng)林。防風(fēng)林是由樹(shù)木和其它植物形成的屏障，農(nóng)民在其農(nóng)田四周種植防風(fēng)林。

Windbreaks help prevent the loss of soil.

防風(fēng)林有助于防止土壤流失。

They stop the wind from blowing soil away. They also keep the wind from damaging or destroying crops.

它們可以防止風(fēng)把土壤吹走，還能防止風(fēng)損毀莊稼。

Windbreaks can be highly valuable for protecting grain crops. For example, studies have been done on windbreaks in parts of West Africa. These studies found that grain harvests were as much as twenty percent higher in fields protected by windbreaks compared to fields without them.

防風(fēng)林在保護(hù)糧食作物方面極具價(jià)值。例如，關(guān)于西非部分地區(qū)防風(fēng)林的研究已經(jīng)完成。研究發(fā)現(xiàn)，與沒(méi)有防風(fēng)林的農(nóng)田相比，防風(fēng)林保護(hù)下的農(nóng)田的糧食收成增長(zhǎng)了20%以上。

But here is something interesting about windbreaks. They seem to work best when they allow some wind to pass through the barrier of trees or plants around a field. If not, then the movement of air close to the ground will lift the soil. Then the soil will be blown away.

但關(guān)于防風(fēng)林還有一些有趣的東西。似乎允許部分風(fēng)穿過(guò)農(nóng)田周圍的樹(shù)木或植物屏障時(shí)，防風(fēng)林起到的效果反而更好。如果不允許風(fēng)穿過(guò)，那么貼近地面的風(fēng)就會(huì)吹起土壤，這樣土壤就會(huì)被風(fēng)吹走。

For this reason, a windbreak works best if it contains only sixty to eighty percent of the trees and plants that would be needed to make a solid line. An easy rule to remember is that windbreaks can protect areas up to ten times the height of the tallest trees in the windbreak.

出于這個(gè)原因，如果防風(fēng)林只包含60%到80%的可以組成一道堅(jiān)固防線的樹(shù)木或植物，它所起到的效果最好。要記住一個(gè)簡(jiǎn)單的原則，防風(fēng)林可以保護(hù)的農(nóng)田寬度可以達(dá)到其最高樹(shù)木高度的十倍。

There should be at least two lines in each windbreak. One line should be large trees. The second line, right next to it, can be shorter trees and other plants with leaves. Locally grown trees and plants are considered the best choices for windbreaks.

每片防風(fēng)林至少要有2行。其中一行是大樹(shù)，挨著的另一行可以是矮樹(shù)或其他帶葉子的植物。當(dāng)?shù)厣L(zhǎng)的樹(shù)木或植物被認(rèn)為是建造防風(fēng)林的最佳選擇。

Studies have shown that some kinds of trees can grow well even if the quality of the land is not very good. One kind of tree is the white pine. Another is the loblolly pine.

有研究表明，某些種類的樹(shù)木即使在貧瘠的土壤也能生長(zhǎng)得很好。其中一種是白松，另一種是火炬松。

Windbreaks not only protect land and crops from the wind. Surplus trees can be cut down and used or sold for wood.

防風(fēng)林不僅可以保護(hù)土地和農(nóng)作物免受風(fēng)災(zāi)。多余的樹(shù)木還能砍下來(lái)用作木材或出售。

Trees reduce the damaging effects of wind and rain. Their roots help protect soil from being washed away. And trees can provide another valuable service for agriculture. They can provide grazing animals with shade from the sun.

樹(shù)木能夠減少風(fēng)雨的破壞性影響。它們的根系有助于防止土壤流失。同時(shí)樹(shù)木能夠?yàn)檗r(nóng)業(yè)提供另一種極具價(jià)值的服務(wù)，他們能夠?yàn)榉拍辽筇峁┦a涼處。