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Presence of different types of trees dispersed singly or in small groups throughout the fields is a very common feature in
the extensive rice paddies of Laos and Thailand. Factors such as land-settlement history, proximity to forest, and role of
species in the local culture are known to influence the nature and distribution of tree species so retained. The extent of
influence of these factors on tree-species composition and distribution in rice paddies was investigated in three villages
in Central Laos: Dongmakngeo, a newly established village with an abundance of adjacent forest; Bak, an old village with adjacent
forest; and Nakhou, an old village without any adjacent forest. At Dongmakngeo village, 23 species, mostly remnants from the
original forest, were observed in paddy fields. At Bak village, few trees were found in the paddy fields because villagers
had ample access to resources in the surrounding large forest. On the other hand, 119 species, 27 of which were planted, were
recorded at the forest-deprived Nakhou village; the scarcity of forest resources at Nakhou was compensated for by the utilization
and management of trees located among the fields, resulting in tree species changing from remnant to ruderal over time. Thus,
our results demonstrate that the pattern of tree distribution and species composition in paddy landscapes is not uniform,
but varies in relation to settlement history, topography, and human management. This has important implications for setting
both landscape-level land-use management plans and local tree management policies for achieving sustainable tropical paddy-dominated
agro-silvicultural systems. 相似文献
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Ricardo Ribeiro Rodrigues Tiago Egydio Barreto Cristina Yuri Vidal 《Forest Ecology and Management》2011,261(10):1605-1613
The complex interactions among endangered ecosystems, landowners’ interests, and different models of land tenure and use, constitute an important series of challenges for those seeking to maintain and restore biodiversity and augment the flow of ecosystem services. Over the past 10 years, we have developed a data-based approach to address these challenges and to achieve medium and large-scale ecological restoration of riparian areas on private lands in the state of São Paulo, southeastern Brazil. Given varying motivations for ecological restoration, the location of riparian areas within landholdings, environmental zoning of different riparian areas, and best-practice restoration methods were developed for each situation. A total of 32 ongoing projects, covering 527,982 ha, were evaluated in large sugarcane farms and small mixed farms, and six different restoration techniques have been developed to help upscale the effort. Small mixed farms had higher portions of land requiring protection as riparian areas (13.3%), and lower forest cover of riparian areas (18.3%), than large sugarcane farms (10.0% and 36.9%, respectively for riparian areas and forest cover values). In both types of farms, forest fragments required some degree of restoration. Historical anthropogenic degradation has compromised forest ecosystem structure and functioning, despite their high-diversity of native tree and shrub species. Notably, land use patterns in riparian areas differed markedly. Large sugarcane farms had higher portions of riparian areas occupied by highly mechanized agriculture, abandoned fields, and anthropogenic wet fields created by siltation in water courses. In contrast, in small mixed crop farms, low or non-mechanized agriculture and pasturelands were predominant. Despite these differences, plantations of native tree species covering the entire area was by far the main restoration method needed both by large sugarcane farms (76.0%) and small mixed farms (92.4%), in view of the low resilience of target sites, reduced forest cover, and high fragmentation, all of which limit the potential for autogenic restoration. We propose that plantations should be carried out with a high-diversity of native species in order to create biologically viable restored forests, and to assist long-term biodiversity persistence at the landscape scale. Finally, we propose strategies to integrate the political, socio-economic and methodological aspects needed to upscale restoration efforts in tropical forest regions throughout Latin America and elsewhere. 相似文献
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以鹤壁淇河国家湿地公园建设为例,针对目前湿地公园建设理论方面的不足,从保护和改善湿地生境入手,探讨了建设国家湿地公园存在的优势、劣势,面临的机遇和挑战。通过对湿地公园进行SWOT分析,指出了建设鹤壁淇河国家湿地公园的重要性,提出了利用湿地公园的地理位置、生物资源、旅游资源、文化资源等优势,以实现鹤壁淇河国家湿地公园建设的可持续发展。 相似文献
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贵州招堤国家湿地公园是全球峰林地貌区岩溶湿地的典型代表,针对湿地公园的建设,在实地调查和查找文献资料的基础上,分析了湿地公园的湿地类型和特征以及湿地公园建设主要胁迫因子和制约因素,提出了湿地资源保护对策与措施,以期为贵州招堤国家湿地公园的建设提供指导与帮助。 相似文献
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利用TM影像对滇西南7个地（州）27个县（市）开展了调查，并按2级分类的要求进行目视解译，其结果为研究区热带林覆盖率为46.09%，郁闭林面积占研究区总面积的10.46%，破坏林面积占总面积的35.63%，常绿阔叶林面积占总面积的32.61%，热带雨林和季雨林面积占总面积的0.20%，判读精度81.53%。表明TM影像能满足热带林宏观林地资源调查的需求，既快速，又省力、省钱，具有一定的实用性。 相似文献
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城市湿地公园被誉为"城市之肾",是重要的国土资源,具有生态修复净化环境等功能。因此对城市湿地公园的土地利用情况进行监测,对环境改善、合理利用土地以及保护湿地资源有重要意义。本文以成都市白鹭湾湿地公园为例,利用ENVI进行监督分类动态监测土地利用前后变化情况,并对其结果进行分析,研究表明:白鹭湾湿地公园2012土地类型划分情况为:植被、耕地/半裸地、人造物/裸地占比分别为42%,33%,25%;2015年土地分类占比分别为42%,20%,22%,同时增加了16%的水体,湿地公园耕地、植被、水体等面积逐年增加,土地利用结构更加合理。通过遥感技术动态监测和土地利用变化分析,有利于湿地公园资源的合理利用,同时对城市湿地的建设具有巨大的促进意义。 相似文献
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林业是以森林资源为经营对象的产业。传统林业认为森林的主要功能就是生产木材。现代林业则认为森林除了生产木材之外 ,还有巨大的综合效益。从福建国有林场场情和林情出发 ,认定现代林业是福建国有林场发展的现实选择 ,阐述了福建国有林场现代林业建设的基本思路和对策措施 相似文献
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通过对古里国家湿地公园地理位置、湿地资源以及国家湿地公园建成后对湿地生态系统保护、湿地恢复、湿地宣传教育和合理利用等方面影响的论述,阐明了建设大兴安岭古里国家湿地公园的必要性。 相似文献
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Thailand aims to increase the use of renewable and alternative energy by 25% of total consumption under the Alternative Energy Development Plan (AEDP 2012–2021) by 2021, which include outputs from energy crops. This initiative is likely to put pressure on land resources, especially near parks and protected areas. Our study examined energy crop plantations, farmer responses to the AEDP, and community roles in forest protection in four villages adjacent to Phu Wiang National Park, Thailand in 2014. The majority of respondents (80%, n = 50) used their land for rice cultivation, but many villagers increased plantings of sugarcane (54%) and cassava (20%) because of high market demand for energy crops. Only a few examples of agricultural expansion into the national park were observed. Nevertheless, encroachment is likely to occur at this and other national parks as a result of government incentives to plant energy crops and the limited availability of agricultural land. Reliance on community-based management strategies may not be powerful enough for villagers to withstand the pressures of modernization, materialism, and other socioeconomic influences, possibly negating the effect of sustainability. Striking an equitable balance between government policies, community development, and forest protection will be a challenge for resource managers. 相似文献
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Joyotee Smith Socorro Ferreira Petra van de Kop Célio Palheta Ferreira Cesar Sabogal 《Agroforestry Systems》2003,58(2):125-135
While slash-and burn farmers convert forest to agriculture, they also regenerate significant areas of secondary fallow forests on their farms. Under what conditions does secondary forest cover persist on slash-and-burn farms? Survey data from Pará, Brazil show that secondary forests occupy 20% of farm area even after a century of settlement. In addition to restoring soil fertility, secondary forests contribute over 20% of farmers' income through products such as charcoal, fruit, game animals and firewood for on-farm processing. Econometric analysis shows that slow rates of population growth and increases in agricultural incomes through on-farm processing of agricultural products enable farmers to maintain long fallows and result in diversified systems compatible with secondary forest cover in the study area. On the other hand, declining agricultural productivity, subsidized credit, declines in the growth rate of secondary forests and policies favoring speculative land acquisition threaten secondary forest persistence. In older settlement areas, secondary forests are often the only forest resource available to the rural poor. Fallow areas should therefore be managed not only for agricultural productivity, but also for conserving forest resources. 相似文献
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Particularly in developing countries, forests provide feed for livestock in the form of fodder for stall-feeding and grazing in forest areas. Extraction of fodder resources from forests often leads to forest degradation. An attempt has been made to qualify extend of biomass extraction from forests and to compare forest fodder dependence of households in a number of forest density classes in the mountainous region of Himalayas, in Uttarakhand state in India, according to livestock owners’ perspectives. Information was obtained from a survey of livestock feed and fodder collection and utilization from 316 randomly selected households distributed across four government-defined forest density classes, namely very dense forest, moderately dense forest, open forest and scrub. Households obtained feed and fodder for livestock from three sources, i.e. forest areas, non-forest areas and local markets. Daily feed consumption per adult cattle unit varied according to source, ranging from 9.85 to 14.70 kg from forest areas, 7.40 to 11.14 kg from non-forest areas, and less than 1 kg from local markets. The dependency of households on fodder for livestock differed significantly between households located in each forest density classes. The current forest fodder extraction rate is likely to be unsustainable. Measures identified to reduce the extraction rate include greater use of alternative fodder sources and managing small patches of the natural forests adjoining dependent villages for fodder production through community participation. 相似文献
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分析当前莆田市国有林场经营管理存在的主要问题和制约因素 ,提出全市国有林场生态公益林与商品林经营管理改革应对措施和配套政策 相似文献
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试论国有林场森林可持续经营对策 总被引：4，自引：2，他引：4
应用森林可持续经营理论 ,采用生态与经济相结合的方法 ,分析福建省国有林场森林经营管理现状及影响可持续发展的因素 ,提出国有林场森林可持续经营对策与措施 相似文献
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Impacts of resource extraction on forest structure and diversity in Bardia National Park,Nepal 总被引：1，自引：0，他引：1
Repeated biomass harvesting for human livelihood needs can cause significant changes in forest structure, composition and diversity. Such impacts have often been associated with the distance to villages and their size, but the effects of individual villages in relation to their characteristics have been little studied. Focussing on the issues around communities’ impacts on the forest, this research aimed to understand how resource extraction by two Buffer Zone villages in Nepal's Bardia National Park affects forest structure and diversity. Tree density, basal area, diameter at breast height (DBH), species richness, two diversity indices and disturbance indices were recorded in 108 plots in 12 transects, from March till May 2005, within the park along the village boundaries, where resource extraction occurs, and in the core park area which is isolated from human disturbance. Forest subject to resource extraction had a lower density of trees, smaller DBH and lower species richness and diversity. Forest disturbance declined with distance from the villages but the two villages differed widely in their impact on the forest. Resource use was more intensive in Shivapur village and percentage of trees lopped, average lopping intensity and numbers of dung piles were statistically significant. This was mainly due to the lack of access to Buffer Zone community Forest for Shivapur households. Interviews with villagers suggested that there have been changes in species availability compared to 5 years ago. Households also underestimated the impact of their resource extraction, which may prevent them from changing their behaviour to benefit conservation. It is clear that understanding rural communities’ needs, their framing of resource extraction and utilisation, and dependence on forest resources will be very helpful for long term conservation measures. 相似文献
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《Forest Policy and Economics》2001,2(1):1-11
Forests expanded rapidly in northwestern Vietnam in the 1990s. Forest expansion coincided with a new forest policy that mandated the devolution of forest management authority. A cornerstone of the new policy was the allocation of use rights for forestry land and trees to rural households. This paper examines to what extent the new forest policy contributed to the observed forest expansion. The findings of three village studies suggest that the new forest policy had minor effects on actual property rights, as villagers resisted its implementation. Instead, forests expanded, mainly due to the liberalization of agricultural output markets and availability of new technology. Changes in markets and technology motivated farmers to intensify crop production, reducing agricultural pressure on land. The research findings suggest the potential of market-based instruments and technology policy to facilitate forest regeneration. They also demonstrate the benefits of in-depth village studies for forest policy analysis, as it provides an integrated framework for assessing the relative effects of political, economic and technological changes on forests. 相似文献
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曹虹 《中南林业调查规划》2014,(4):38-41
在实地调查的基础上,结合对文献资料的整理,分析了贵州思南白鹭湖国家湿地公园的湿地类型、面积、分布以及动植物资源,梳理了湿地资源面临的威胁和保护管理中存在的主要制约因素,提出了湿地保护和恢复的对策和措施,以期为白鹭湖国家湿地公园的保护和恢复提供借鉴。 相似文献
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