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1.
贵州省湄潭县属于典型的适竹少竹县,现有竹林面积4 691.3 hm2,新增竹林潜力较大,可以通过退耕还竹、低效林改竹和"四旁地"造竹新增竹林15 600 hm2,达到20 291.3 hm2的竹林总量。发展竹产业存在竹林分布零散、利用率不高、加工基础薄弱等问题,但也有立地条件和土地资源等适宜竹林培育的优势条件。由此文章提出了竹产业发展的对策：分类培育,提高现有竹林质量;挖掘土地潜力,规划培育笋、材、景观兼用竹林;扶持笋竹加工,开发竹产品市场;强化科技服务,保障竹产业技术需求;设置管理机构,有序推动竹产业发展。 相似文献
2.
For the countries struggling with climate change, sustainable forestry is one of the greatest challenges and is difficult to define, implement, and to measure. According to the scientific community’s consensus on climate change, forests are one of the major sinks and sustainable forest management (SFM) is needed to prevent deforestation and its negative effects on natural ecosystems. Despite being a party to many international treaties/agreements related to land use policies (LUP) that are promoting SFM to protect and develop forest resources, the 2/B application in Turkish forest legislation has been causing deforestation in Turkey since the 1970s.
In this study, 2/B applications–political and legal process–causing deforestation by land use change (LUC) are investigated by carrying out a legal analysis. About 500.000 ha of forests have been lost due to the 2/B application and as a LUP directly affects SFM, carbon sequestration capacities (CSC), and therefore, climate change. To exemplify this pre and post-LUC change and effect, the amount of carbon that was prevented from being absorbed as 176,7 tonnes/ha on average in a given forest area for the year 2016. There is a vital need to address the negative effects of ill-defined forest legislation to achieve SFM. 相似文献
3.
基于2013年安化县森林资源规划设计调查数据、2017年林地变更调查数据,利用地理信息系统软件及景观格局指数计算软件,分析安化县天然林景观格局特征,对安化县天然林空间格局与动态演变进行研究。结果表明:安化县天然林主要是由竹林和阔叶林组成,占安化县天然林总面积的80%以上;从天然林整体变化情况来看,2013—2017年安化县天然林面积整体呈减少趋势,各森林类型斑块密度、景观类型比略有变化,天然林景观整体变化不大,景观维持平衡稳定;天然林景观在空间分布趋于聚集分布,连接状况趋于更佳,天然林斑块的形状趋于更规则、更复杂,景观格局趋于更好。 相似文献
4.
Tropical forests are the world’s largest terrestrial storehouses of carbon and are recognized as rich, diverse and highly productive ecosystems. The present study was conducted to characterize the land use, diversity and biomass of tropical forest in Western Ghat of Maharashtra State in India through satellite remote sensing and GIS. The study has been designed and implemented to promote analysis on Western Ghat biodiversity resources including trees, shrubs and herbs based on inventorying, monitoring and mapping. Field measured biomass is integrated with spectral responses of various bands and indices of the Landsat TM satellite image for estimation of above-ground biomass in a 36,046 km2 area of relic forest in the Central Western Ghat. The above-ground biomass from field-based inventory varied from 30.2 to 151.1 ton/ha in moist deciduous forest, 9.2–99.1 ton/ha in dry deciduous forest, 42.1–158.6 ton/ha in semi-evergreen forest, and 160.9–271 ton/ha in evergreen forest. The total above-ground biomass of the study area was estimated to be 95.2 M tons. A regression equation between field above-ground biomass and a Normalized Difference Vegetation Index was used for spectral modeling to estimate and prepare the above-ground biomass map in the region. A total 120 plant species in 81 genera and 31 families were identified in the study area. This study emphasizes the importance of relic forests for their biodiversity, carbon sequestration and total biomass. 相似文献
5.
XIAO Jianmin WU Zhiping . Research Institute of Forestry Policy Information Chinese Academy of Forestry Beijing P. R. China . Research Institute of Forestry Chinese Academy of Forestry Beijing P. R. China 《中国林业科技(英文版)》2007,6(1):57-61
This study provides basis information for estimating the feasibility of the environmental and ecological forestry construction project in the area. Through the survey in Miyun watershed, the economical benefits of carbon sequestration in five typical forest types have been studied by calculating the biomass from the timber accumulation data and converting to the money value. The results show that： in the duration of 100 years, at a discount rate of 5%, and 197 RMB yuan/t as the price of the carbon sequestration, the present value （PV） of the carbon sequestration in different forests are： 6900-9300 yuan/ha in Chinese pine forest,6100-8200 yuan/ha in oak forest, 4500-6100 yuan/ha in other broadleaf forests, 2300-3200 yuan/ha in shrubs and 1300-1800 yuan/ha in cypress forest. The annual mean economic benefit of carbon sequestration is 770-1040 yuan/ha. The pine forest has the highest carbon sequestration benefit, followed by oak forest, other broadleaf forest, shrubs, and cypress forest. If the land is suitable for all forests, pine forest and oak forest should be planted in order to sequestrate more carbon. 相似文献
6.
基于"3S"技术,采用总体蓄积抽样控制、小班调查、消耗量调查等方法,查清了师宗县各类土地面积和各类森林蓄积、林木和林地资源的种类、数量、质量,落实了森林分类经营区划,对调查数据动态变化进行了分析,提出了加强天然林保护、商品林多功能经营、发展林下经济和生态旅游等林业发展建议。 相似文献
7.
Mohammad Samaun Safa 《Small-Scale Forestry》2006,5(2):207-229
The encroachment rate in forests in Bangladesh is high and increasing — accelerated by rural poverty and the demand for dwelling
space and forest products — causing environmental degradation as well as loss of forest cover and productivity. The forests
are managed by the Forest Department, although a substantial area of marginal land belongs to other semi-public agencies including
Roads and Highways and the Water Development Board. This marginal land has been left unused or underutilized. In contrast,
nongovernmental organizations have an appropriate accessibility and technology disseminating ability to utilize this land
in reducing poverty and enhancing rural livelihood, and have been highly active and successful in rehabilitating encroached
forests. NGOs have added a new dimension to forest management, which has ensured community participation and protection of
the forests, both planted and natural. This study evaluates the social forestry activities of four large NGOs, namely BRAC,
Proshika, Caritas and CARE-Bangladesh, as well as national social forestry activities. By adopting a common partnership between
public and private authority, property right conflicts have been resolved and rural livelihoods enhanced, and scope has been
created for utilizing marginal land. The NGO partnership has been effective in reducing poverty and improving livelihoods.
As an outcome of this common partnership, 33,472 km of roadside planting and 53,430 ha of reforestation activities have been
carried out during the last two decades. 相似文献
8.
介绍曲靖市近年来防护林体系、天然林保护工程、退耕还林工程等林业生态建设状况。对森林生态系统脆弱,石漠化土地治理任重道远,林业产业结构不合理,林业基础设施依然薄弱等林业生态建设面临的形势进行分析,藉此提出了林业生态建设发展思路、建设重点及对策措施。 相似文献
9.
我国热带林资源现状与发展 总被引：2，自引：0，他引：2
我国热带林主要分布在海南、云南西南以及福建、广东和广西沿海地区,面积约１１４０．７６万ｈｍ＾２。尽管热带林面积仅占全国森林面积的８．５３％,但其在生态环境保护方面却发挥着重要作用,国家先后采取禁止天然林采伐、建立热带林自然保护区、加强热带人工林和沿海防护林基地建设、加大资金和科技投入等一系列政策和措施加以保护,使其能够持续发展。到２０１０年,我国热带林将得到恢复和发展,面积将达１４９２．８万ｈｍ＾２,其中商品林、公益林及兼用林面积将分别为８１１．５万ｈｍ＾２、６１０．８万ｈｍ＾２和７０．５万ｈｍ＾２,沿海防护林体系及林业生态和产业两大体系基本建成。 相似文献
10.
澳大利亚国土面积为768万km2,林地面积占国土面积的13.8%。森林主要分布在东南沿海一窄长地区。该国经营林业的战略是:以发挥森林的生态环境利用为主。澳国将全国林地面积的77%划为环保林,其中501万ha划为森林保护区和国家森林公园。天然成熟林实行凭证定量采伐。与此同时,大力发展速生优质人工林。其主要树种为辐射松和南洋杉,并以此代替低产的桉树林。目前占林地总面积2%的人工林,其采伐量已占全国采伐量的40%。在经营强度上,人工林大于天然林。扩大林业经济效益的主要途径是发展纸浆和造纸工业。澳大利亚把在一定时期内保持林产品进口,作为保存、发展本国森林资源的保护战略。 相似文献
11.
森林生态系统历史变迁的经济学解释 总被引：1，自引：0，他引：1
人类经济的发展从来就是用相对丰富的资源替代相对稀缺的资源.从采集渔猎,到刀耕火种,最后进入永久农业的过程,从经济学角度分析就是在技术不断更新下人造资本取代自然资本的过程.历史上一直是原始林被次生林和农地取代,只是在近百年来,许多国家和地区相继出现林地取代农地的现象.人工林也成为木材生产的主要来源,同时还相继出现许多专门为人类提供生态服务的森林.森林变迁主要原因是农业技术革新和人口变化导致农产品、林产品以及森林资源生态服务的相对价值变化的结果.本文用美国、新西兰以及中国的海南岛为例来验证这一原理,从经济学的角度提出对未来森林生态系统的展望. 相似文献
12.
林业科技是第一生产力应表现为劳动者实物生产率和林地实物生产率的增长。40年来, 这两个指标都是徘徊不前的。作者同意林业需要综合治理的主张, 科技要与经济、行政措施结合一起, 促进林业生产力的提高。 相似文献
13.
人工林和天然林的比较评价 总被引：23，自引：3，他引：20
对人工林和天然林的生态学和林学特性进行了比较和分析。指出天然林对病虫害的抵抗能力强,能持久地生产木材和发挥多重效益,并与很多物种的生存有密切关系。因人工林多样性低,稳定性差,轮伐期短,集约栽培的工业人工林尽管速生,但对地力消耗大,若没有优越的土地条件和额外的施肥,生产力将不能持久。提出我国应实行人工林和天然林并重的方针,要对大量发展工业人工林可能产生的隐患给予重视,要对已保存不多的原始林实行不改变林相的经营方式,避免将它们大面积地改变为人工林的作法。 相似文献
14.
15.
通过在滨海沙地上营造木麻黄、湿地松混交林,林农轮作,幼林施肥以及对山地黑松低产林改造等技术措施。结果表明。改造后的林分,不但可以充分利用林地生态资源,提高林分的生产力和收获量,扩大造林成效,而且对改善生态环境也有特殊的效益。 相似文献
16.
中国热带林资源和利用现状及２０００年发展前景朱敏慧（中国林科院科信所,北京１０００９１）１中国热带林资源概况中国的热带林处于热带北缘,属干湿交替型的热带向干热带过渡地带,按区域划分大体可分为３个地带：（１）东部过渡性热带季雨林、雨林区,包括福建东南部... 相似文献
17.
《Forest Policy and Economics》2008,10(5):295-302
The maximum clearcut size and green-up period is important for land managers adhering to voluntary and regulatory guidelines. Therefore the impact of actual and hypothetical clearcut size restrictions is a concern for forest landowners who manage land and intend to practice forestry for profit. In this research, the effect of a 97.1 ha (240 ac) clearcut size constraint with a green-up period of 2-yrs is assessed for forest landowners with different forest land sizes, ownership patterns, and age class distributions. A meta heuristic which consists of threshold accepting, 1-opt tabu search, and 2-opt tabu search is used to develop spatially-constrained forest plans for 27 hypothetical forest landowners. These results are compared to a relaxed solution produced with linear programming, and statistical analyses are used to determine significant differences. The analysis provided enough evidence to suggest that two factors (size of ownership pattern and initial age class distribution), and one interaction factor (ownership size × initial age class distribution) are significant in explaining the differences in the percent reduction in forest plan value among the forests managed by the hypothetical forest landowners. From an absolute value reduction perspective, small-sized older forests were most affected. From a percent value point of view, one can conclude from this analysis that landowners with small-sized forests and young initial age class distributions will be significantly more affected by potential adjacency and green-up restrictions in the southeastern U.S. than other types of landowners. 相似文献
18.
Conversion of natural forests to other land use results not only in a decrease of forest area but also in the degradation
of remnant forests as a habitat for forest animals. Although such degradation due to an increase of forest edges has been
studied most intensively, other factors such as forest shape may also contribute to the degradation. In this study, we compared
bird abundance and species richness between irregular-shaped and relatively continuous forests in the breeding and migratory
seasons. Since the forests were surrounded by tree plantations rather than open lands, the edge effect may have been weak
at the study site. Our results suggested that the irregular forest shape negatively affected forest bird abundance and species
richness in the breeding season, but not in the migratory season. The response of birds varied with bird traits: migrants
avoided the irregular-shaped forest, but residents did not. Among the residents, small ones preferred or tolerate the irregular-shaped
forest whereas large ones avoided it. This study indicates that careful consideration of various factors such as seasonality
and bird traits is needed to understand the consequences of land use changes on forest birds. 相似文献
19.
对发展我国速生丰产林有关问题的思考 总被引：16，自引：1，他引：15
本文在明确速生丰产林概念的基础上, 着重探讨了发展速生丰产林在我国林业建设中的地位, 澄清了国内外不同林业发展战略思路(如接近自然的林业, 林业分工论, 新林业学说和生态林业等) 与发展速生丰产林的关系.最后根据园内外发展速生丰产林(工业人工林) 的经验和教训, 指出今后我国速生丰产林的发展道路及应注意的问题. 相似文献
20.
联邦德国天然林保护区借镜 总被引：1，自引：0，他引：1
联邦德国和中欧地区的天然林基本消失。从1970年开始,联邦德国各州相继把天然林或近乎天然状态的林分划设为天然林保护区。到1982年,除黑森州外,共划设350个保护区,其中的大多数面积各为10-20公顷,仅6个超过100公顷,75个少于10公顷。所有保护区受国家有关法规如森林法、自然保护法及林业方针政策和公告等的保护。为加强天然林的研究,1979年拟定了包括森林学、植物学、土壤学、区域动物学、森林立地及历史等方面的"天然林保护区科学研究纲要"。 相似文献