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1.
The Amazon forest in the state of Maranhão ensures ecosystem services that directly and indirectly affect the life quality of its population and economy, via hydrologic and climatic regulation, among other benefits. Currently, only 25% of the original forest cover (24.7 thousand km2) remains while illegal deforestation persists in a violent process that provokes visible social, economic and environmental harm. Simultaneously, Maranhão has seen record levels of burning, faces a water shortage and fights against the worst social and economic indicators in the country. Conversely, secondary vegetation covers 19.9 thousand km2 (27% of deforested area) and is completely unprotected. Contrary to the international commitments assumed by Brazil to combat deforestation and restore forests, some of the political representatives of Maranhão have sought legal mechanisms to further diminish forest cover in public and private areas. To promote the conservation and restoration of Maranhão Amazon Forest, a multi-institutional network of researchers was established in 2015. This viewpoint paper aims to draw attention to this endangered region of the Brazilian Amazon and give science-oriented recommendations to policy makers in order to avoid more setbacks. We argue that Maranhão state must urgently establish a policy of Zero Deforestation, protect secondary forests and comply with the national forest restoration policy, thus ensuring long-term economic sustainability.  相似文献   

2.
The year 2019 in Brazil was marked by environmental setbacks, which catalyzed the increase of illegal deforestation and fire rates in the Brazilian Amazon. In the Amazon region of Maranhão state, original forest cover diminished from 25 % (24,700 km2) in 2016 to 24 % (23,967 km2) in 2019, and 6,038 km2 of remaining forests were degraded by fires and/or illegal logging – processes related to high levels of violence against indigenous and rural communities. Almost half of all deforested areas in the region (36,060 km2) are considered a global restoration hotspot, however secondary vegetation remains unprotected and 8,294 km2 were cleared between 2014 and 2018. Due to uncontrolled deforestation and fragmentation, Maranhão has no more forest core areas (outside protected areas) with the minimum size to ensure sustainable forest management practices for timber production. New policies at the state level must promote old-growth and secondary forest conservation and restoration. However, the trends point to the opposite direction: the Ecological-Economic Zoning (ZEE) allows the reduction of forest protection and the State Forest Policy reinforces federal legislation setbacks. The Amazon region of Maranhão state has forest aptitude, and forest and agroforestry product chains would bring social and environmental benefits, making them the best opportunity for sustainable economic development in the region. Therefore, the forest must be re-planted for the benefit of people and nature.  相似文献   

3.
东北红松阔叶混交林的特点及其分布规律   总被引:2,自引:0,他引:2  
红松阔叶混交林在东北东部山区分布极为广泛,是该地区水平地带性和垂直地带性森林;将东北红松阔叶混文林分为3部分:典型阔叶红松混交林,河岸、河谷阶地阔叶红松混交林和山脊、陡坡阔叶红松混交林;介绍了红松阔叶温交林组成、分布规律及其地势的特点。  相似文献   

4.
基于2005—2014年大兴安岭图强林业局碳汇造林项目的项目地潮河林场、奋斗林场、二十八站林场和育英林场的数据,建立结构方程模型对森林碳汇项目促进减贫的影响因素及其之间的关系进行实证分析。结果表明:森林碳汇项目通过促进社会就业情况和经济情况有助于减缓贫困,并且社会就业情况在减贫影响上比经济状况贡献度高;而森林碳汇项目造林阶段的造林面积对减缓贫困在一定程度上呈正相关关系。通过结果分析表明只有基于内生发展动力和贫困人口的自我发展能力的森林碳汇项目开发设计,由"输血型"模式变为"造血型"模式,才能更好地实现应对气候变化和缓解贫困两个目标。  相似文献   

5.
The semiarid region in the state of Sergipe, Brazil, approximately 11,000 km2, has experienced high deforestation rates in the last decades, which ultimately contribute to global climatic changes. The valuation of ecosystem services of CO2 sequestration can support definition of environmental policies to decrease deforestation in that region. This study aimed to assess land use and land cover changes in the Sergipe semiarid region between 1992 and 2017 by applying remotely sensed data and technics; simulate the land use and land cover changes between 2017 and 2030 by applying a cellular automaton model, by assuming current land use trends (Business as Usual – BAU) as a reference scenario, and a more conservative scenario (Protected Forest – PF), in which was assumed an effective enforcement of the Brazilian Forest Code established in 2012; simulate the carbon stocks by 2017 assuming the BAU and PF scenarios by 2030, and estimate the Carbon balance between the 2030 and 2017 scenarios; and estimate the economic valuation of carbon emission and sequestration by using the InVEST software. The results showed that agriculture (cropped lands) was main driver of the landscape changes in the study area, which increased 14% by 2017, a net increase of 1494.45 km2. The results showed that the total Carbon emissions would reach 736,900 Mg CO2-eq by assuming the BAU scenario, which would increase the cost of opportunity up to US$ 17.7 million and a social carbon cost varying between US$ 10.3 and US$ 30.2 million. The restoration of the permanent preservation areas could contribute to increase Carbon sequestration up to 481,900 Mg CO2-eq by 2030, which is equivalent cost of US$ 11.6 million. The natural landscape in the Sergipe semiarid region was strongly affected by deforestation activities occurred between 1992 and 2017. It requires, therefore, effective actions to support and promote restoration of degraded areas. The forested areas within the Sergipe semiarid region were the most affected type of vegetation because of expansion of agricultural fields soil exposures (Exposed Land). Environmental assessments based on scenarios and economic valuations can provide crucial information to support policy and decision makers to improve strategies for environmental management and conservation.  相似文献   

6.
Increased demand for both agricultural production and forest restoration may lead to increased competition for land in the next decades. Sustainably increasing cattle ranching productivity is a potential solution to reconcile different land uses, while also improving biodiversity conservation and the provision of ecosystem services. If not strategically implemented in integration with complementary policies, sustainable intensification can however result in negative environmental, economic and social effects. We analyzed the potential for sustainable intensification as a solution for a conflict between agricultural expansion and forest restoration in the Paraitinga Watershed at the Brazilian Atlantic Forest, a global biodiversity hotspot. In addition, we provide policy recommendations for sustainable development in the region, based on interviews with producers and local actors. We found that the Paraitinga Watershed has the potential to increase its cattle-ranching productivity and, as a result, relinquish spared land for other uses. This was true even in the most conservative intensification scenario considered (50% of the maximum potential productivity reached), in which 76,702 ha of pastures can be spared for other uses (46% of total pasture area). We found that restoration, apiculture and rural tourism are promising activities to promote sustainable development in the region, thus potentially increasing food production and mitigating competition for land. Our study shows that results from socioeconomic interviews and biophysical modelling of potential productivity increases offer robust insights into practical solutions on how to pursue sustainable development in one of the world’s most threatened biodiversity hotspots.  相似文献   

7.
In this paper we analyze the indirect land use change (ILUC) effects of ethanol production expansion in Brazil through the use of an inter-regional, bottom-up, dynamic general equilibrium model calibrated with the 2005 Brazilian I-O table. A new methodology to deal with ILUC effects is developed, using a transition matrix of land uses calibrated with Agricultural Censuses data. Agriculture and land use are modeled separately in each of 15 Brazilian regions with different agricultural mix. This regional detail captures a good deal of the differences in soil, climate and history that cause particular land to be used for particular purposes.Brazilian land area data distinguish three broad types of agricultural land use, Crop, Pasture, and Plantation Forestry. Between one year and the next the model allows land to move between those categories, or for unused land to convert to one of these three, driven initially by the transition matrix, changing land supply for agriculture between years. The transition matrix shows Markov probabilities that a particular hectare of land used in one year for some use would be in another use next period. These probabilities are modified endogenously in the model according to the average unit rentals of each land type in each region.We ask whether biofuel expansion is consistent with new laws, limiting forest clearing in Brazil. A simulation with ethanol expansion scenario is performed for year 2020, in which land supply is allowed to increase only in states located on the agricultural frontier. Results suggest that each new hectare of sugar cane requires only 0.14 ha of new land, with another 0.47 ha converted from pasture use. Hence policies limiting deforestation are unlikely to prevent greater ethanol production. Finally, regional differences in sugarcane productivity are found to be important elements in ILUC effects of sugar cane expansion.  相似文献   

8.
Collaborative governance and landscape approaches have become a more prevalent in public land management in the United States in the face of increasing ecological and societal complexity and decreasing government resources and capacity. In this era of devolution and social-ecological change, there is a growing need for policy approaches that facilitate partnerships and participatory approaches to land management. One unique policy that emphasizes collaboration and large-landscape restoration on US federal forestlands is the Collaborative Forest Landscape Restoration Program (CFLRP), established in 2009 to accelerate the pace and scale of forest restoration. The policy included novel characteristics such as a decade-long commitment to landscapes and formal requirements for collaboration. This program presented an opportunity to assess how this policy affected collaboration and the factors that led to differential policy implementation. We conducted 89 interviews across all 23 CFLRP projects with internal agency staff and external collaborators on each project. We found that the CFLRP generated a variety of benefits related to collaboration, including increased trust and stronger relationships, increased collaborative partner influence, decreased litigation and conflict, and increased capacity to accomplish work; however, there were also challenges associated with the program, including thetime-intensive nature of collaboration and the lack of industry or contractors. Various local factors affected collaborative outcomes under the policy, including staff turnover and capacity, local leadership, and collaborative history. Successful collaborative outcomes were widespread under the CFLRP, and from this, we draw implications for the broader environmental governance literature about the policy characteristics that facilitate collaboration and the other institutional variables that may require attention in this context.  相似文献   

9.
通过测算2003~2014年黑龙江森工林区相对于东北、内蒙古重点国有林区和全国的林业产业结构相似度,以及黑龙江森工林区多种经营业内部的产业结构相似度,得出:东北、内蒙古重点国有林区林业产业结构趋同性问题严重,增加了林区全面停伐后的经济转型压力;2010年后黑龙江森工林区相对于全国的林业产业结构相似度持续下降,产业转型实践取得一定成效;黑龙江森工林区不同林管局之间多种经营产业结构一致性突出,不利于依托其突破停伐困境和进一步深化国有林区经济转型。为此,建议黑龙江森工林区持续发挥比较优势,积极构建区域一体化产业格局等,充分应对国有林区全面停伐、经济转型和林区改革的新形势。  相似文献   

10.
东北国有林区森林食品产业结构水平与空间集聚特征分析   总被引:1,自引:0,他引:1  
基于产业经济学理论,构建了森林食品产业结构水平与产业集聚程度的评价指标体系和多指标综合指数模型,对东北国有林区森林食品产业结构水平与产业集聚程度的综合指数进行测算和分析。研究结果表明:产业结构水平表现最优的为吉林集团,产业集聚程度表现最优的为龙江森工集团,二者表现均较差的为大兴安岭林业集团;在产业结构水平评价中,龙江森工集团表现略优于大兴安岭林业集团,二者差距不大,但在产业集聚程度评价中,大兴安岭林业集团与龙江森工集团和吉林集团存在较明显的差异。为了促进东北国有林区森林食品产业持续快速发展,必须进一步规范森林食品产业标准化生产及认证流程,加快推动森林食品产业品牌建设,依靠科技创新提高森林食品产业科技含量,优化森林食品产业市场布局拓展投融资渠道,完善森林食品产业扶持政策体系。  相似文献   

11.
剖析了东北内蒙古国有林区现存管理体制下政企不分,管资源与砍树木同出一家及其带来的问题,介绍了内蒙古重点国有林区2007年底以来的改革实践与探索。内蒙古重点国有林区通过管理体制改革,初步理顺森工与政府的关系,强化了林管局的林业生态建设管理职能和国有森工企业的经营职能,优化了生产关系和发展环境。从根本上解决内蒙古国有林区管理体制问题的关键是强化林管局职能,在剥离企业社会职能的同时,赋予林管局林业行政许可权。  相似文献   

12.
Establishing forest protection standards is essential for biodiversity conservation and for ensuring the public water supply. This study evaluated whether compliance with environmental legislation aimed at protecting the Atlantic Forest is sufficient to minimize the negative effects of urban pressure on the conservation of biodiversity in the water source area of the Billings reservoir in the municipality of Diadema. To assess the effectiveness of environmental legislation, we created a current land use and land cover map as well as maps for an expected legal scenario and evaluated both using landscape metrics. Our findings indicate that forest resource availability in the area is critical but can be improved by compliance with legal obligations, which have complementary effects and the potential to promote less fragmented landscapes. On the other hand, they do not prevent the tendency of fragmentation caused by the surrounding urban matrix, which can reduce the positive effect of the legal compliance on forest conservation in cases of consolidated urban areas.  相似文献   

13.
大兴安岭森林火烧对土壤生境质量影响研究   总被引:1,自引:0,他引:1  
森林火烧是一种自然或人为因素产生的干扰,能够改变当地土壤的物理性质、化学性质及生物指标,对土壤的性质与土壤的肥力影响较大,对农业生态系统的结构与功能影响深远。作为我国重点的国有林区,大兴安岭地区林地面积广阔,森林覆盖率高,是我国生态安全的重要保障区,拥有丰富的林业资源,林下适生农业经济作物有500多种,林木、柞蚕、林果及中草药等绿色种养产业的资源十分丰富,是当前大兴安岭发展现代农业的主要模式。大兴安岭是我国森林火灾的多发区,文章对近年来国内专家学者对火烧影响森林土壤的理化性质与生物指标等众多研究成果进行综合评述,近年来,研究者从大兴安岭不同地区、不同林火种类与林火强度系统分析并研究了火烧对土壤生境质量的影响,该文通过对其进行归纳总结,旨在为该地区的火烧迹地植被恢复及农业林下经济的科学经营管理提供科学依据。  相似文献   

14.
Although the regulations are imperfectly enforced, logging firms in the Brazilian Amazon are subject to forest management regulations intended to reduce environmental damage and protect future forest productivity. Additionally, voluntary best practices firms adopt to achieve environmental performance that exceed regulatory requirements are largely limited to reduced impact logging (RIL) systems that reduce harvest damage relative to conventional logging systems used by a large majority of firms in the region. Existing regulations combined with best practices may not be adequate to ensure sustained yields. This inadequacy is an important issue as Brazil implements an ambitious program of forest concessions on public lands. We analyze the profitability and environmental outcomes of best logging practices and proposed sustainability requirements. We propose two operational definitions of sustainability (the first focusing on sustaining stand-level timber volumes and the other focusing on sustaining species-level volumes within the stand) based on sustaining timber inventories across cutting cycles rather than on sustaining overall harvest yields. RIL is shown to be profitable for loggers and increase the timber available for future harvests. While volume predicted to be available for the second and third harvests are significantly lower than the available timber in the unlogged forest, the second and third harvests are projected to be profitable and have the potential for sustainability despite high opportunity costs. However, as harvesting is repeated into the future, results show the composition of the harvest shifts from higher-value shade-tolerant and emergent species toward a greater reliance on longer-lived, lower-value pioneer species. This shift may create pressure to expand the forest base under management in order to continue to supply high-value species or increase the risk of timber trespass in conservation units and areas under community or indigenous management.  相似文献   

15.
In Brazil, the Forest Code requires landholders to maintain fixed-width buffers of native vegetation along watercourses – legally called Areas of Permanent Preservation (APPs). In 2012, agricultural activities started to be partially allowed in APPs, but only if best management practices on soil and water conservation are adopted and if a narrow buffer strip with native vegetation is restored adjacently to the watercourse. In this paper, we present a modeling framework to investigate the capacity of legal compliant APPs to supply watershed services (erosion control and stream bank stabilization) in a 2,200 ha watershed in São Paulo State, Brazil. Our results suggest that the narrower the riparian buffer the lower the control of soil erosion dynamic within APPs, and that riparian buffers smaller than 8 m can act as a source of sediments to streams. The adoption of best management practices can contribute to controlling soil erosion within APPs but the presence of native forests in the first 15 m is necessary to guarantee equivalent protection to streams when compared to APPs completely covered by forests. Moreover, we observed that forest restoration within APPs helped to reduce the average soil loss of the watershed by only 20 %, compared to a reduction of 55 % when best practices are implemented in all watershed agricultural areas. We conclude that (i) the reduced requirements for APP restoration may contribute to stream sedimentation, which will likely affect the supply of watershed services by stream ecosystems; (ii) the implementation of best management practices in APPs will not have the same effect as native forests to reduce stream sedimentation; and (iii) the adoption of best management practices in all agricultural production areas – and not only within APPs as required by law – is the best strategy to promote the supply of watershed services to society.  相似文献   

16.
Up to 80% of each private rural property in the Brazilian Amazon is protected by law through the Legal Reserve (LR) mechanism of the federal Forest Code, underlining the conservation importance of forests on private lands in one of the world̿s most important biomes. However, our understanding of the discrepancies in levels of forest protection on private lands as obligated by the law versus what occurs in practice remains very poor. We assessed patterns of forest cover and legal compliance with the Forest Code in the 1.25 Mkm2 Brazilian state of Pará, which has the highest deforestation rate in the Amazon. We evaluate the LR deficit and surplus patterns for different sized properties and across 144 municipalities, and found that the total LR surplus (12.6 Mha) was more than five times the total area of deficit (2.3 Mha). Yet, from the total surplus, only 11% can be legally deforested while the remaining 89% is already protected by law but can be used (sold or rented) to compensate for areas that are under deficit. Medium and large-scale properties make up most of the total LR deficit area, while agrarian reform settlements had comparatively large amounts of both compensation-only surplus and deforestable surplus. Most of the municipalities (77%) in the state could compensate their total deficit with surplus areas of LR in the same municipality, while the remainder can be compensate their deficit in one or more neighbouring municipalities, indicating compensation can always take place close to the source of the deficit. Maximising the environmental benefits of achieving Forest Code compliance requires measures that go beyond the existing legal framework, including interventions to avoid further deforestation in places where it is still legal, compensate in close proximity to areas with legal reserve deficit and promote local restoration on degraded lands.  相似文献   

17.
[目的]人工造林对生物多样性恢复和城市森林功能发挥的影响深远,科学评估人工造林对生态系统恢复速度及稳定性的影响是实现生物多样性保护的基础。[方法]采用格网法获取北京浅山区276个样本单元,根据2010年、2015年和2018年土地利用类型数据,选择多样性、丰富度、均匀度和优势度4个测算指标,分别测算各期生物多样性指数及时空格局,运用OLS回归和分位点回归评价"百万亩"造林对浅山区生物多样性的影响方向和程度。[结果](1)2018年北京市浅山区林地覆盖率达到51.66%,林地面积较2015年增加了3 400hm~2,且林地二级类型间变化较大;(2)2018年北京市浅山区多样性指数、丰富度指数、均匀度指数和优势度指数均值分别为0.432、0.544、0.504和0.276,多样性和均匀度有小幅度降低,但丰富度和优势度提升明显。(3)不同分位水平下,人工造林对浅山区生物多样性的影响方向和程度并不一致,在10%分位水平下,样本单元内林地面积的快速增加均对各项生物多样性指数有显著的促进作用,但影响程度不同。[结论]人工造林应综合考虑源地物种分布状况、造林类型和优势林种等多方面因素,才能最大程度发挥其对生物多样性的修复和保护作用。  相似文献   

18.
长江上游地区森林植被的恢复对策   总被引:1,自引:0,他引:1  
刘志文 《林业经济问题》2002,22(5):249-252,257
本文分析了恢复森林植被是长江上游地区生态环境建设的主体,长江上游地区恢复森林植被中存在的主要问题,提出了恢复森林植被的指导思想、基本原则、对策措施和政策建议。  相似文献   

19.
在对东北国有林区林产工业产业组织结构矛盾分析的基础上,以国有林区林产工业组织结构重构为基点,提出了林产工业组织结构重构的指导思想、目标和途径,目的在于促进东北国有林区林产工业产业发展。  相似文献   

20.
森林旅游产品的适宜性评价是森林公园开发旅游产品的主要参考依据,对于旅游产品开发的成功具有重要意义。从产品的竞争力、资源条件、市场需求与定位、开发效益、外部协调性等几个方面对福州国家森林公园鸟语林产品的适宜性程度进行了实证评价。  相似文献   

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