Добавлены профессиональными переводчиками и компаниями и на основе веб-страниц и открытых баз переводов.
consequently the southward movement of sand dunes was completely controlled and large areas of farmland were brought under effective protection by the shelterbelts.
因此完全控制了南移的沙丘，而且将大片的农田置于防护林带的有效保护之下。
widening of the genetic base of clones used in reforestation, shelterbelts and afforestation programmes in order to increase productivity, introduce resistance to frost and drought, and reduce overall susceptibility to pests and diseases, was a major goal.
（iii）制定杨树长期选种计划，通过收集、试验和评估中国北部及其它地方类似生态系统中业已存在的杨树无性系， 迅速改进造林所用无性系的活力、形态及抗霜抗病虫害的能力。
(a) techniques developed in arid xinjiang and gansu provinces for establishing narrow shelterbelts systems, which play a large role in preventing farmland from wind hazards and sand disasters, should be applied in the semi-arid regions and dry sub-humid areas in regions where physical conditions are similar;
在干旱的新疆自治区和甘肃省开发出了建立防护林带系统的技术方法，这种方法对于农田风害和沙灾防护发挥了重大作用，应当向物理条件类似区域的半干旱和亚湿润偏旱地区转让和推广这种方法；