查询词典 cover crop

They sell short as many futures contracts as it takes to cover their prospective crop.

他们增产时就会尽力做空期货。

In agriculture,it influences the monoculture, crop rotation,crop cover and so on.S ome allelochemicals can be...

培育新的抗虫害、抑草品种，分离、鉴定新的化感物质，深入揭示化感作用的机制，是今后化感作用的研究重点。

Crop insurance will cover a portion of farm production losses attributable to Hurricane Katrina, the drought and other adverse weather conditions this year.

作物保险将包括飓风"卡特里娜"、干旱及其它不良天气造成的部分农产品损失。

The testing results indicate there is a visible regulating effect in soil temperature with crop residue cover.

试验结果表明，残茬覆盖对土壤温度有明显的调节作用，5、10、15、20 cm各层有覆盖相对于无覆盖分别增温1.5~2.1℃、0.9~1.2℃、0.2~0.9、0.4~0.8℃，随着土壤层的加深，覆盖对土壤温度的调节作用越来越小。4月20日至6月15日前后，随着覆盖量的增加，土壤温度开始升高，但覆盖量增加到一定程度后，土壤温度将下降，在6月20日以后，随着覆盖量的增加，土壤温度逐渐降低，其中30%覆盖相对于无覆盖，降低1.1~1.5℃，50%~80%覆盖降低2~3.6℃，而表土层降低幅度最大，沿深度方向幅度越来越小。

BMP production systems will encourage quicker ground cover, more crop residues, greater root growth and more leaf area, all of which will improve N use efficiency and reduce erosion.

最佳管理措施生产体系将有助于迅速覆盖地表，产生较多的作物残留，促进根系生长和增加叶面积，这些都会提高氮素利用率同时降低侵蚀。

They urged "a rapid shift, whenever and wherever conditions permit it, to management systems based on minimal soil disturbance, increased soil cover, and appropriate crop rotation".

他们敦促，"无论何时何地，只要条件许可，应迅速向以最低限度干扰土壤，增加土壤覆被和适当的作物轮作为基础的管理系统转变"。

The value of roughness is depended on landscape, vegetation cover and crop cultivation direction, the larger the roughness is, the less the wind erosion intensity is.

地表粗糙度反映地表对风速减弱的作用以及对风沙流的影响，其值大小取决于地形、植被覆盖及作物的播种方向，粗糙度越大风蚀强度越小。

For testing the effect of crop residue cover on soil temperature at various percentages of covered areas,the test plot was established in west rainless region of Heilongjiang Province.

在黑龙江省西部干旱区建立不同残茬覆盖对土壤温度影响试验区，采用W QG-16。

Effects of no- till in the different cover on conditions on crop yield in different cover on conditions were studied in dry land in the middle of the Loess Plateau, DingXi. Results showed that under the no-till form, Pea general increase output, agricultural input costs have decreased significantly , the average saves 810 Yuan / hm2; Under the different cover condition, the net income separately increases 1175.45, 1682.70, 968.25 Yuan / hm2, the economic efficiency is obvious.

本文通过在定西旱地农业地区实施保护性耕作，对免耕在不同覆盖条件下的豌豆产量进行了试验研究，结果表明：在免耕措施下，豌豆产量普遍增加，农业成本投入得到明显降低，平均节约810元/hm2；在不覆盖、秸秆覆盖和地膜覆盖的条件下，纯收入分别增加1175.45、1682.70、968.25元/ hm2。

As the crop remains in place during3-4 years, various cover crops are intercropped o keep enough residue cover.

免耕种植的紫花苜蓿作物残茬可以在田里保持3－4年，不同作物间作提供了足够的残茬覆盖。

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。