论文部分内容阅读
实践证明直干桉、蓝桉、赤桉,大叶桉、细叶桉等十多种桉树在云南是有发展前途的树种。但这些桉树过去多种植于四旁、坝区和低山丘陵。而云南是一个多山的省份,全省土地面积的84％是山地,约10％是高原,坝子(盆地、河谷)仅占6％,横断山山脉纵贯滇西,乌蒙山、五莲峰盘延滇东北。全省129个县、区、市中,有93个县的坝子面积占本县土地面积的比例还不到10％,其中53个县是在3％以下,全省有18个县99％以上的土地全是山地。因此要在云南大力发展桉树生产就必须考虑桉树上山问题,但干湿季分明又是云南省区别于其它省的一个重要气候特点。11～4月西风南支急流把印度半岛北部大陆干而暖的空气引导过来,形成晴天多,日照充足,气温高,空气干燥的干季。5～10月在西南季风和东南季风影
Practice has proved that straight eucalyptus, blue eucalyptus, Eucalyptus urophylla, Eucalyptus grandis, Eucalyptus urophylla more than 10 kinds of eucalyptus in Yunnan is a promising species. But these eucalypts used to be planted around the country, the dam area and the hilly hills. Yunnan is a mountainous province. 84% of the province’s land area is mountainous. About 10% of the area is plateau. Bazi (basin and valley) only accounts for 6%. The Hengduan Mountains runs through western Yunnan, Wumeng Mountain, Peak extension Yunnan northeast. In 93 counties, districts and cities in the province, the area of Bazi in 93 counties accounts for less than 10% of the total land area of the county, of which 53 counties are below 3% and the province has over 99% of 18 counties The land is all mountainous. Therefore, in order to vigorously develop eucalyptus production in Yunnan, it is necessary to consider the eucalyptus uphill. However, the clear wet and dry seasons are also an important climatic feature that distinguishes Yunnan from other provinces. From January to April, the westerly jet stream led the dry and warm air from the northern mainland of the Indian Peninsula to form a dry season with more sunny days, abundant sunshine, and warmer air and air. May to October in the southwest monsoon and southeast monsoon