共查询到20条相似文献,搜索用时 81 毫秒
1.
华南地区山地木麻黄引种试验 总被引:6,自引:0,他引:6
介绍了山地木麻黄天然分布区的生态条件、主要生物学特性和用途等。通过在海南和广东两省多点引种试验,结果表明,山地木麻黄在华南地区的生长表现较好,其树高,胸径和单株材积生长显著地大于其它5种木麻黄,且适合在赤红壤地区种植。 相似文献
2.
3.
通过福建中部山地引种木麻黄造林试验,5 a的研究结果表明:木麻黄无性系与实生苗造林保存率都较高,分别达到98.15%和96.8%,差异不显著。试验还表明,采用木麻黄无性系造林,其树高、胸径、材积的生长明显优于木麻黄实生苗的生长速度。前者比后者三项主要指标的生长量增加25.0%、26.5%和94.2%,差异较为显著。采用木麻黄优良无性系造林,其林木干型通直、冠幅大、林相整齐;应用实生苗造林,个体分化较大、生长参差不齐。 相似文献
4.
2004年.我局在石门乡许台流域治理示范区魏岔村山地开始四倍体刺槐引种栽植试验.通过两年多的观察和记录,现将引种栽植试验情况分析如下: 相似文献
5.
在气候干燥、寒冷的西北地区 ,引进具有耐干旱、贫瘠 ,抗寒冷 ,抗盐碱等多种优良特性的常绿或准常绿饲料灌木四翅滨藜 ,经过 2a生长全过程的栽培试验 ,观测结果表明 :在不同土壤类型下 ,新梢生长量、扦插育苗的成活率、保存率都表现出差异性。但移栽苗的成活率、保存率差异不大 ,表现出较强的适应性。而在中、强盐碱性土壤、(粗 )砂土中仍能正常生长 ,但新梢生长量低 ,分枝减少 相似文献
6.
鸡尖在闽南山地的引种与栽培技术 总被引:1,自引:0,他引:1
鸡尖(Terminalia hainanertsis)使君子科落叶乔木,原产海南,热带树种,一类商品材。心边材区别小,材色鲜淡一致,波纹柔和美观,材质坚硬而重,耐海水浸渍,干燥后不开裂,不变形,很耐腐,是优良的造船、桥梁、车辆、建筑、家具等优良用材。我们于1964年从海南引进在厦门及周边闽南山地栽植。 相似文献
7.
8.
11.
12.
13.
14.
乌江流域山地农林复合经营模式研究 总被引:2,自引:0,他引:2
以乌江流域坡耕地为背景、调查总结了坡耕地水土流失的特点和农林复合经营复模式现状,分析论证了农林复合经营模式的生态经济的综合效益。提出了乌江流域林农复合经营的造林设计原则依据和布局与配置等系列实用技术,为长防工程建设这耕还林工种提供科学依据。 相似文献
15.
Surface area processing in GIS for different mountain regions 总被引:1,自引:0,他引:1
Surface area is a fundamental parameter derived from terrain analysis in geographical information systems (GIS) for modeling the real world. Therefore, an evaluation of the techniques implemented by GIS models is important in order to obtain reliable area measurements. The study compares two raster-based methods with a TIN-based (triangulated irregular network) method for surface area approximation using a digital elevation model (DEM) with 25 m × 25 m resolution in six mountain regions of Shandong Province, China. Raster-based method Ⅰ calculates surface-area grids from DEMs directly. Eight 3-dimensional triangles connecting the center point of each cell with the center points of the eight surrounding cells are generated and then the areas of the portions of each triangle that lay within the cell boundary are calculated and summed. Raster-based method Ⅱ produces the surface area of each cell directly from the pixel size and the slope value for the pixel. The results demonstrate that the surface areas calculated by raster-based method Ⅰ are equal to those of the TIN-based method. The results of raster-based method Ⅱ are the lowest but the difference in areas between the two raster-based methods decreases with the decrease in terrain complexity. Compared to the method with TINs, raster-based method Ⅱ can do better because it has some advantages, such as neighborhood analysis, more consistent output and faster processing speed. The results also demonstrate that the difference between surface and horizontal areas should be considered if more than 30% of the area of a region has slopes steeper than 18.2 degrees. 相似文献
16.
介绍了邵武市引种撑绿竹、硬头黄竹、坭竹、单竹、青皮竹及大眼竹的成活率、出笋率等生长情况,并就福建省北部山区纸浆竹林苗圃基地建设有关问题进行了探讨。 相似文献
17.
18.
19.
针对山区马尾松毛虫适合烟剂防治的特点,选用1.2%苦.烟乳油喷烟进行山区马尾松毛虫防治试验。结果显示:该药具有速效、低毒、彻底的特性,从经济高效的角度考虑,9倍液稀释浓度适合山区松毛虫防治,害虫死亡率达97.6%,可取代目前生产上常用的菊酯类化学农药喷烟控制马尾松毛虫危害。 相似文献