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胡杨(Populus euphratica)在额济纳荒漠绿洲中的生态地位极其重要,与绿洲的兴衰息息相关。额济纳荒漠绿洲的胡杨林,目前由于河水泛滥受控制,使依赖于河漫滩而发芽生长的幼林所占林地面积比例下降,林地日趋老化、衰残,致胡杨日渐衰败,绿洲退缩。文中依据多年的试验调查数据,对荒漠河岸林胡杨残林复壮更新效果进行了分析研究。结果表明:围栏封育对加快荒漠河岸林的复壮更新和林下天然植被的恢复,起到了积极而显著的作用。开沟断根,打破了土壤表皮板结层,疏松了土壤,利于根蘖苗萌生,同时也促进了苗木侧根和须根的增加,扩大了根系吸收面积,使苗木生长量提高。间苗定株有效地促进了胡杨老树的根蘖更新。确定了河岸胡杨更新林合理密度为幼龄期为3330株/hm2,中龄期为1665株/hm2,近熟林期为600株/hm2,成熟林期为135株/hm2。在此基础上提出了全面保护好沿河现有胡杨残林的措施,实行分片、分段围栏封育和充分引用季节性河道来水浇灌的前提下,积极促进胡杨残林的复壮和根蘖更新,复壮更新。
The ecological status of Populus euphratica in Ejin Desert Oasis is extremely important and closely related to the rise and fall of oasis. Eupolyphaga desert oasis Populus euphratica forest, due to the current flood control, so that rely on the river floodplain growth and development of young forest area accounted for a decrease in the proportion of forest area, woodland aging, decay, resulting in the gradual decline of Populus euphratica, Oasis retreat. Based on years of experimental investigation data, the rehabilitative effect of the remnant forest of Populus euphratica forest was analyzed. The results showed that the enclosure of fences played an active and significant role in accelerating the rejuvenation and restoration of natural riparian forests. Open up the ditches, breaking the soil epidermal layer, loose soil, conducive to the germination of root tillering seedlings, but also to promote the growth of lateral roots and fibrous roots, expanding the root absorption area, so that nursery stock growth. Thinning seedlings effectively promote the regeneration of root tillers of old trees. The rational density of Populus euphratica forest was 3330 plants / hm2, 1665 plants / hm2 in middle age, 600 plants / hm2 in nearly mature forest and 135 plants / hm2 in mature forest. On this basis, the measures to comprehensively protect the existing Populus euphratica forest along the river are put forward. On the premise of slicing, subdivided fencing and sufficient use of seasonal river watering, we should actively promote the rejuvenation and root growth of Populus euphratica forest Tiller update, rejuvenation update.