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通过对平潭岛岩质海岸带裸露山体采取多种方式进行植被恢复试验,结果表明:各树种的保存率均较高,除迎风坡台湾相思和夹竹桃的保存率为85%和88.33%外,其他树种的保存率均达到了94%以上。主要乔木树种侧风坡的生长量均显著大于迎风坡;除迎风坡及风障外的木麻黄和台湾相思受风沙危害,有部分长势较差,出现基干干枯之外,其他树种60%以上均长势优良;肯氏南洋杉受风害影响最小,其次为台湾相思、木麻黄和夹竹桃。风障对造林树种的生长起到了很好的保护效果,风障内的木麻黄保存率、地径和树高生长均显著高于风障外。 相似文献
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本文用空间代时间的方法研究了长宁县竹林退耕还林在时间序列上的植被恢复特点。除毛竹外,和一般树种相比,竹类恢复为森林的时间较短,3 a~5 a即可成林。但竹种类型间成林速度存在差异,丛生竹成林最快,散生竹较慢。梁山慈竹和硬头黄竹退耕后可以一次成林,毛竹退耕可先进行农林复合经营直到群落郁闭。随着竹林的恢复,草本层生物量逐渐减少,地被物层生物量增加,各竹种新生个体的生态位逐渐扩大。人工栽植5 a的毛竹扩散规律研究结果表明,随着毛竹栽植时间的延伸,毛竹产生的新竹数目增多,个体变大,距离变远(170 cm),也存在大小年变化。人工促进竹林植被恢复速度明显较快。 相似文献
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中西部地区退耕还林还草模式探讨 总被引:27,自引:2,他引:27
在将我国退耕还林还草工程区划分为 2个大区 9个类型区的基础上 ,研究了每个大区的退耕还林还草基本技术思路和每个类型区的退耕还林还草模式 ,包括其类型区域范围、自然资源特点、社会经济特点、主要限制因子、基本技术思路、林草类型结构、植被恢复方式、植被恢复技术、主要树种草种、经营管护方式等 相似文献
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黄土高原植被生态恢复评价、问题与对策 总被引:22,自引:1,他引:22
以中国水土流失与生态安全综合科学考察西北黄土区考察组获得的资料为依据,对黄土高原植被恢复方面取得的成就、存在的问题和未来的发展策略进行综合评价分析.退耕还林和禁伐禁牧措施实施以来,黄土高原地区植被覆盖率、质量已经呈现稳定提升的势态,民众生态环境保护意识增强,植被恢复措施优化,多元化投资与城镇化发展使黄土高原植被恢复前景较好.目前存在的主要问题是:植被恢复投资力度不够;政策不稳定使农户无远期规划,政策不配套,使大户承包治理停滞;过分注重经济效益,人工经济林比例过大,生态功能不强;禁伐禁牧封禁措施缺乏技术支撑,许多重大理论问题亟待解决.未来植被恢复策略包括:明确不同时期植被恢复目标和完善恢复途径;保护现有成果,增加自然恢复和生态修复比例;用政策保护承包大户植被建设的积极性;加大植被建设和科研投资力度,培育黄土区植被恢复方面的科技创新能力. 相似文献
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【目的】为了更好地利用半干旱黄土丘陵区的土地资源,促进该区域植被恢复,提高生物多样性,使区域生态环境有所改善。【方法】以半干旱黄土丘陵区龙滩流域的植被为研究对象,对该流域11种典型的土地利用类型(2种农地、自然荒草地、人工牧草地、撂荒草地、灌木林地、5种乔木林地)的植被物种组成和多样性进行了调查研究。【结果】流域内共调查到种子植物56科166属254种,其中裸子植物门3科7属13种,占流域总科、总属、总种的5.36%、4.22%、5.12%;被子植物门53科159属241种,占流域总科、总属、总种的94.64%、98.78%、94.88%。在被子植物门中,双子叶植物纲有50科134属205种,单子叶植物纲有3科25属36种,两纲物种分别占流域总种数的80.71%和14.17%,占该门物种总种数的85.06%和14.94%。不同土地利用类型植被多样性分析结果表明,物种丰富度表现为农地物种丰富度低,人工牧草地、撂荒草地和灌木柠条林地居中,乔木林地(山杏、山毛桃、油松、侧柏、青杨)和天然荒草地高;物种多样性表现为马铃薯农地的物种多样性低,覆膜农地、人工牧草地、撂荒草地及灌木柠条林地居中,自然荒草地和乔木林地比较高;物种均匀度表现为农地、撂荒草地、人工牧草地及灌木柠条林地的均匀度高,自然荒草地居中,乔木林地低。【结论】不同土地利用方式和植被演替恢复时间差异是产生植被多样性差异的基础,也是该区域植被恢复和物种多样性保护需要考虑的重要要素。 相似文献
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A group of scientists conducted a comprehensive investigation on ecological safety and water and soil erosion in the Northwest
Loess Plateau, Northwest China. The data gathered was analyzed in terms of achievement, existing problems, and strategy and
measures on vegetation restoration in the area. Since the policies of conversion from cropland to forest (CCF) and forbid
grazing and cutting (FGC) were carried out, vegetation quality and coverage rate increased quickly in the Loess Plateau area,
strengthening the concept of eco-environment protection. Environment harness measurements were optimized. The multiform investments
on eco-environment and urbanization development in China will benefit vegetation restoration. However, there have been some
persisting problems, such as the shortage of investment, instability of government policy, expectation of extravagant economic
benefit, larger rate of plantation, and scarce technologies supporting vegetation restoration. Many key theories and practice
problems require an urgent resolution. In the future, short-, mid-, and long-term goals for vegetation restoration should
be clear, achievement should be expanded, and the natural restoration area should be increased. The benefit for the contractor
on vegetation restoration should be ensured. Investment on vegetation building research work should be increased.
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Translated from Scientia Silvae Sinicae, 2007, 43(1): 102–106 [译自: 林业科学] 相似文献
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中国海岛植被修复的适生植物 总被引:2,自引:0,他引:2
海岛的脆弱性与人为的干扰造成海岛植被生态逐年恶化,亟需开展修复工作。文中介绍了中国海岛植被修复现状、海岛适生植物筛选与引种,认为开展海岛植被的优势种调查将是海岛植被修复树种筛选的重点,可为植被生态修复工作提供借鉴。文中将中国海岛划分为庙岛群岛组、浙江海岛组、闽粤岛屿组、台湾岛组和海南岛组5组,综述了海岛地带性植被、砂生生态类群、盐生湿地生态类群、基岩生态类群、海岸林生态类群的优势种,列出了可应用于中国海岛修复的适生植物种类,并对我国筛选及开发利用具有海岛植被恢复特色的植物提出了建议。 相似文献
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Two contrasting trajectories for vegetation restoration in agricultural landscapes are secondary succession following cropland abandonment that can regenerate woodlands (passive restoration) and conversion of cropland to tree plantations (active restoration), which have mostly focused on pine species in the Mediterranean Basin. We compared the effects of these two contrasting trajectories of vegetation restoration on bird assemblages in central Spain. Vegetation structure differed in the two restoration trajectories, pine plantations attaining higher tree cover and height (31% and 4.1 m, respectively) but lower strata complexity than secondary shrubland and holm oak woodland (which attained 10% and 1.4 m of tree cover and height, respectively). Bird species richness differed in stands under active or passive restoration trajectories, the former collecting a higher total number of species (4.2 species per 0.78 ha plot) than the latter (3.5 species per plot). The number of forest species increased with vegetation maturity in both restoration trajectories, but especially in stands under active restoration. The occurrence of woodland generalist species increased and of species inhabiting open habitats decreased in actively restored stands, being some of these latter species of high conservation priority in the European context but relatively common at the regional level. Bird species inhabiting pine plantations had broader habitat breadth at the regional level than those inhabiting secondary shrublands and woodlands. Maximum regional density did not differ between both restoration trajectories, but it increased with development of the herbaceous layer only at the secondary succession trajectory. The relative importance of species of European biogeographic origin was higher in mature pine plantations (58.9% of total bird abundance) than in mature holm oak woodlands (34.4%), whereas that of Mediterranean species was considerably higher in the latter (40.1%) than in the former (20%). Bird assemblages of relatively small patches of pine plantations are unable to reflect the regional avifauna, in contrast with the relationships between local and regional assemblage characteristics that can be found in isolated natural forests. We conclude that programs of vegetation restoration should base upon a range of approaches that include passive restoration, active restoration with a variety of tree and shrub species, and mixed models to conciliate agricultural production, vegetation restoration and conservation of target species. 相似文献
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我国退耕还林工程建设成效问题及对策 总被引:1,自引:0,他引:1
系统地总结了我国退耕还林工程在改善生态环境、增加农民收入、调整农村产业结构、提高农业综合生产能力、促进农民思想观念转变等方面取得的成效,分析了退耕还林工程建设中存在的突出矛盾和问题,根据“完善政策,巩固成果,稳步推进,确保质量”的要求,提出了进一步搞好退耕还林工程建设的对策和建议。 相似文献
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五种植被恢复模式对邵阳县石漠化土壤理化性质的影响 总被引:1,自引:0,他引:1
通过野外土壤剖面调查和采集土壤样品,对比研究5种植被恢复模式(侧柏纯林、枫香+侧柏林、枫香纯林、湿地松+枫香林、湿地松纯林)下土壤理化性质,探讨不同植被恢复模式对邵阳县喀斯特地区土壤理化性质的影响。研究结果表明:5种植被恢复模式中侧柏纯林、枫香+侧柏混交林以及枫香纯林呈碱性,而湿地松+枫香混交林以及湿地松纯林生长速度快,7年生的湿地松平均胸径7.79 cm,平均高5.07 m,土壤呈酸性;土壤含水率较低,并相差不大,其中上坡位的枫香纯林土壤含水率最小,只有18.11%;土壤质量密度从大到小的顺序为:侧柏纯林、枫香纯林、湿地松+枫香混交林、湿地松纯林、侧柏+枫香混交林,土壤孔隙度则相反。土壤全P、全K、全Ca、全Mg、全Fe、Zn、Cd、速效N和速效K的含量在不同植被恢复模式中差异显著(p0.05),其中,土壤有机质和土壤全Ca的含量差异最为明显;不同植被恢复模式中的土壤全N、Cu、Mn、速效P的含量差异不显著,只与土壤的本底值有关。 相似文献
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文章总结了巴中市巴州区退耕还林工程的实施情况和取得的主要成效,分析了当前退耕还林工程可持续经营存在的主要问题,提出相应的解决对策与建议。 相似文献