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为了探讨不同栽培模式橡胶林的物种多样性,运用植物群落生态学方法,对云南省西双版纳州传统橡胶园、改造型橡胶园和雨林橡胶园3种栽培模式橡胶人工林的结构、种类组成和物种多样性进行了研究。结果表明,群落垂直结构复杂程度改造型橡胶园雨林橡胶园传统橡胶园;雨林橡胶园物种组成最为丰富,有维管束植物30科46属51种,改造型橡胶园有维管束植物25科34属34种,传统橡胶园植物组成最简单,有维管束植物14科16属19种,乔木层仅单一树种组成;乔木层橡胶树的重要值雨林橡胶园改造型橡胶园传统橡胶园;乔木层、灌木层、草本层的物种多样性指数在3种模式中都表现为雨林橡胶园改造型橡胶园传统橡胶园,改造型橡胶园和雨林橡胶园模式能显著增加乔木层的多样性指数。 相似文献
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<正> 云南在橡胶园内开展多层次的热带、南亚热带作物种植试验研究(亦称“人工群落”研究始于1961年。试验研究和生产应用结果表明:有利于橡胶树防寒的种植行距放宽为9~14米,每亩种植28~37株的合理密度下,橡胶树成林郁闭9~14年,在胶园郁闭前,于行间距橡胶树一定距离(以免造成橡胶树寒害烂脚)间种非生产期短、投产后前期产量高、植株矮小、产品市场需求量大的云南大叶茶、咖 相似文献
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就间种黄豆的和未间种黄豆的杉木幼林进行比较研究,结果表明:间种黄豆的杉木幼林能增加相对湿度7.3%,降低地表温度2.8℃;间种黄豆的杉木幼林的土壤中有机质、全氮、全磷、水解氮和速效磷显著增加;间种黄豆的杉木幼林的幼树高生长和生物量明显增加;间种黄豆能提高经济效益,补偿幼林抚育费用。 相似文献
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采用深穴整地、穴底植苗、草灌覆盖的造林新方法,可有效地保持土壤水分,土壤含水率超过了水平梯田整地常规植苗造林的林地;造林2a后落叶松保存率达95.6%,常规造林仅为52.4%,对提高干旱地区落叶松造林成活率有显著作用;落叶松幼树高度和当年生长量均比常规植苗造林的高。 相似文献
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ZhangZihui ZhangZhiyit LinShanzhi LiXinguo 《中国林学(英文版)》2003,5(2):23-29
Effects of seven planting densities on the growth and tree form of nine 5-year-old new clones in Populus tomentosa were studied. The plantations, arranged with completely random block design, were located in Wuzhi County, Henan Province.Results indicated that effects of planting density on the diameter at breast height (DBH), individual volume and growing stock increment of all new clones in P. tomentosa were significant at the 1% level of probability, effects of planting density on the tree height increment of new clones B2 and B31 and on the live branches height (LBH) increment of new clones B5 and B30 were significant at the 5% level of probability, while the interaction between planting density and clone was not significant at the 5% level of probability. It was concluded that the degree of differences among new clones within the same planting density was different with different planting densities and traits. For short rotation industrial timber, clones B 1, B3, B4, B5, B7, B9, B31 were suitable with the density of 1 000-2 500 trees per hectare, while for bigger diameter timber, clones B1, B3, B4, B7, B9, B31 could be used with the planting density of 660-833 trees per hectare. Clonal repeatability was also different in different planting densities. 相似文献
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We examined the post-planting consequences of pre-planting exposure stress on two-year-old, bare-root Corsican pine (Pinus nigra Arnold. ssp. laricio var. Corsicana) seedlings. Seedlings were lifted from a nursery and exposed to ambient conditions for periods of up to 192 h before being planted in minirhizotrons. Exposure decreased seedling water potential, CO(2) assimilation rate, leaf conductance and new root elongation, and increased mortality after planting. During exposure, needle total nonstructural carbohydrates (TNC) concentration (expressed on a dry mass basis) decreased by 0.31 mg g(dm) (-1) h(-1); however, needle and root TNC concentrations remained high (> 100 mg g(dm) (-1)) at planting, even in those treatments leading to severe seedling mortality. More than 90% of the seedlings with predawn water potentials lower than -1.3 MPa at planting did not elongate new roots and did not survive, whereas a similar percentage of seedlings with a predawn water potential above this value at planting elongated new roots and survived, suggesting that this value corresponds to a turgor threshold below which new root formation is inhibited. At planting, embolization of xylem conduits in roots and shoots was low for seedlings in all of the exposure treatments. 相似文献
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通过地造林规格与造林图式关系的分析,得出改变造林株行距(密度不变),可使林林种植点分布均匀合理,有利于林木生长。建议传统的造林规格应予改变,新的造林规格应予普及推广。 相似文献
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从营林与采运生产间的客观联系以及提高新的制度安排的运行效率出发,研究提出国有林区新的营林与采运生产间关系的形成动机和实质体现的是市场机制的结果.主要包括体现专业化分工的市场联系,在市场机制作用下的一体化联系,以及营林与采运生产间的松散联合.新的关系制度的形成要从打破现行的联系入手,分别建立营林生产主体和采运生产主体,依据市场经济原则在各经营主体自愿互利的原则下建立起一体化或松散联合型的关系状态. 相似文献
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压苗栽植是花椒抗旱造林的一个新的栽植方法.用这种方法造林,幼树根系发达,成活率、保存率高,幼树结果早,产量高。以2a生的1级苗压苗造林效果最好。春、夏、秋三季造林均有较高的保存率,但从幼树生长情况来看,春季优于夏季,夏季优于秋季。 相似文献
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四倍体刺槐生态饲料林栽培试验 总被引:1,自引:0,他引:1
四倍体刺槐是近几年培育成功的刺槐新品种,它不但保持了普通刺槐的原有属性,同时又具有很多新的特性.通过对四倍体刺槐生态饲料林栽培技术的试验研究,结果表明,不同定植密度对苗木成活率无显著影响,但对采割量影响显著.以每667 m2定植3 300株枝条采割量最大;四倍体刺槐2号和5号与普通刺槐相比,粗纤维和粗蛋白含量高,灰分含... 相似文献
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