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Oil palm plantations in Indonesia have been linked to substantial deforestation in the 1990s and 2000s, though recent studies suggest that new plantations are increasingly developed on non-forest land. Without nationwide data to establish recent baseline trends, the impact of commitments to eliminate deforestation from palm oil supply chains could therefore be overestimated. We examine the area and proportion of plantations replacing forests across Sumatra, Kalimantan, and Papua up to 2015, and map biophysically suitable areas for future deforestation-free expansion. We created new maps of oil palm plantations for the years 1995, 2000, 2005, 2010 and 2015, and examined land cover replaced in each period. Nationwide, oil palm plantation expansion occurred at an average rate of 450,000 ha yr−1, and resulted in an average of 117,000 ha yr−1 of deforestation, during 1995–2015. Our analysis of the most recent five-year period (2010–2015) shows that the rate of deforestation due to new plantations has remained relatively stable since 2005, despite large increases in the extent of plantations. As a result, the proportion of plantations replacing forests decreased from 54% during 1995–2000, to 18% during 2010–2015. In addition, we estimate there are 30.2 million hectares of non-forest land nationwide which meet biophysical suitability criteria for oil palm cultivation. Our findings suggest that recent zero-deforestation commitments may not have a large impact on deforestation in Sumatra, where plantations have increasingly expanded onto non-forest land over the past twenty years, and which hosts large potentially suitable areas for future deforestation-free expansion. On the other hand, these pledges could have more influence in Kalimantan, where oil palm driven deforestation increased over our study period, and in Papua, a new frontier of expansion with substantial remaining forest cover.  相似文献   

3.
An efficiency analysis revealed the relative magnitude of wood traits that distinguishes efficient radiata pine logs to produce New Zealand structural grades. Technical and cost efficiencies were obtained by using data envelopment analysis (DEA). Wood trait prices used to perform the cost efficiency corresponded to economic weights derived from a partial regression. These values were 1.1, 29.7, 0.3 and ?0.4 NZ $/m3 for small end diameter (cm), stiffness (GPa), basic density (kg/m3) and largest branch (mm) respectively. The most efficient logs were those with the highest difference between recovery value and price. There were positive and significant correlations between technical efficiency and wood stiffness (0.46, p < 0.05) and between cost efficiency and log recovery value (0.85, p < 0.05). The most efficient logs had a ratio of 1:4 between stiffness and small end diameter whereas logs that did not generate structural lumber presented ratios close to 1:8. This information will inform the development of breeding objectives, and help segregating and pricing logs by using traits patterns that result in efficient logs for the production of structural wood.  相似文献   

4.
In a chestnut belt in the northern Apennines (Italy), we interviewed current (n = 52) and potential growers from a younger generation (n = 57), to assess what factors are likely to drive their willingness to continue chestnut culture. In 35 cases, local appraisals of chestnut stand disturbances were also contrasted with expert assessments. More than half of current growers were confident about the future of chestnut cultivation. This proportion decreased with grower’s age and experienced issues, while slightly increased in presence of multifunctional management and support from family members. Although most growers resulted highly capable of diagnosing problems, expert advice significantly contributed to driving positive perceptions. About half of the younger interviewees also expressed interest in growing chestnut. This proportion was higher for respondents who are exposed to chestnut culture within the family, and who value cultural services above other ecosystem services (ES) of forests. Overall, passion for the activity and attachment to local heritage were the most influential motivation for both categories of respondents. We outline policy actions that may encourage the continuation of chestnut management and, more generally, conservation of cultural landscapes in mountain areas. Possible measures include financial incentives (e.g., payments for ES), tighter integration of traditional and expert knowledge in the production chain, and public recognition of the value of local heritage in land management. Broader support to maintaining services and infrastructure in rural areas, however, will also be a pre-condition.  相似文献   

5.
我国原木进口变化趋势及其影响因素   总被引:2,自引:0,他引:2  
随着我国经济飞速发展,国内对木材的需求不断增长,而我国木材产量无法满足国内旺盛的需求,木材供求矛盾日益突出。因此,近10年来我国木材进口量大幅增长,特别是原木的进口量占了很大比重。文章先简要介绍了我国木材产量和原木进口情况,然后分别描述了木材产品进口结构的变化和原木进口来源地的变化,最后分析了影响原木进口变化的诸多因素,指出生产效率、社会政策和便利性是促使我国原木进口高速增长的主要因素。  相似文献   

6.
Mangroves have been systematically exploited in Indonesia since 1800, especially for the development of brackish water shrimp aquaculture (called ‘tambak’) and for timber harvesting. By the end of the 1960s, Indonesia is estimated to have lost more than 200,000 ha of its mangroves mostly in Java and Sumatra. The rate of mangrove loss started to dramatically increase in the 1970 when exploitation shifted to new areas outside Java, particularly in Kalimantan and Sulawesi, encouraged by government policies to boost timber production, followed by policies to expand tambak in 1980s and large scale tambak development triggered by increased shrimp price during Asian financial crisis in 1997. The result has been the loss of nearly 800,000 ha of mangroves in only 30 years, mostly now in the form of low productivity or abandoned tambaks. In recent years, timber harvesting activities in Indonesia's mangroves appear to have become more sustainable. Our analysis suggests that aquaculture will continue as the main driver of change in mangrove ecosystems in Indonesia followed by palm oil plantation. Failure to deal with the current low productivity of shrimp aquaculture in many parts of Indonesia will force shrimp producers to clear an estimated 600,000 ha more mangroves to make way for shrimp farms over the next two decades. However, with improvements in brackish water aquaculture productivity, halting palm oil concession to utilise mangroves, along with maintaining other mangrove use pressures at moderate levels, the net loss of mangroves in the next two decades could be reduced to around 23,000 ha.  相似文献   

7.
李健  何继新  荆涛 《林业经济问题》2013,33(1):27-31,35
根据协整理论和格兰杰因果检验方法,对中国木质林产品进口和国内木材市场消费量及木材年产量之间的关系进行了实证研究。分析结果表明:中国木质林产品进口与木材消费量及年产量之间存在长期稳定的均衡关系,同时在滞后期为1的情况下木质林产品进口与木材市场消费量和木材年产量之间存在单向的格兰杰因果关系。据此,在分析国内木材供需的基础上,提出了大力发展人工林、提高木材利用率、优化进口市场结构等对策建议,以解决对进口木材依赖的问题。  相似文献   

8.
结合中国木材企业生产和经营特征,认为企业可以采用经过森林FM认证的木材原料和经过合法性认证的木材原料保证木材原料来源合法性,可以进行森林企业产销监管链Co C认证和自建完备的产销履历制度保证产销流程可追溯性。研究结果表明:木材合法性贸易要求会造成企业生产成本上升、生存压力不断加大、盈利空间进一步缩窄,但也能给企业带来销售收入增加的有利影响。  相似文献   

9.
This study examines the effects of different coal, natural gas and carbon emission prices and market situations on the use of wood for electricity and heat production in the European Union. The analysis is carried out using the global forest sector model EFI-GTM expanded to cover electricity and heat production from wood, coal, natural gas, wind and solar energy. Analysis shows that with low coal and gas prices, use of wood for energy will be limited to low cost logging residues. With high coal, and especially natural gas prices, industrial wood also comes to be used for energy. At a carbon price of 100 €/tCO2, some 32 Mm3 of industrial wood, in addition to 224 Mm3 of logging residues, are projected to be used for electricity and heat in the EU region (including Norway and Switzerland) in 2030. The relatively low quantity of industrial wood used by the energy sector despite the collapse of the use of coal is explained by the fact that under high CO2 prices, other energy forms like natural gas, solar and wind energy become more and more competitive. However, the amount of industrial wood used for energy may substantially increase with subsidies for using wood for electricity and heat, even with relatively low carbon prices. With a high coal and gas price and a carbon price of 100 €/t, a subsidy of 30 €/MWh to the wood based and coal with wood co-firing electricity production will have a significant impact on the European wood based sector. Depending on the development of the market demand for forest industry products, such a subsidy may cause a 10–12.5% reduction in forest products production, a 6–9% increase in harvest level, about 30–60% increase in the pulpwood prices, and a 6–9 fold increase of wood imports in the EU, compared to the respective case without a subsidy in 2030.  相似文献   

10.
This paper examines the potential and the cost of promoting forest carbon sequestration through a tax/subsidy to land owners for reducing/increasing carbon storage in their forests. We use a partial equilibrium model based on intertemporal optimization to estimate the impacts of carbon price (the tax/subsidy rate) on timber harvest volume and price in different time periods and on the change of forest carbon stock over time. The results show that a higher carbon price would lead to higher forest carbon stocks. The tax/subsidy induced annual net carbon sequestration is declining over time. The net carbon sequestration during 2015–2050 would increase by 30.2 to 218.3 million tonnes of CO2, when carbon price increases from 170 SEK to 1428 SEK per tonne of CO2. The associated cost, in terms of reduced total benefits of timber and other non-timber goods, ranges from 80 SEK to 105.8 SEK per tonne of CO2. The change in carbon sequestration (as compared with the baseline case) beyond 2050 is small when carbon price is 680 SEK per tonne of CO2 or lower. With a carbon price of 1428 SEK per tonne of CO2, carbon sequestration will increase by 70 million tonnes of CO2 from the baseline level during 2050-2070, and by 64 million tonnes during 2070–2170.  相似文献   

11.
Tropical forests potentially contribute to global climate change mitigation through carbon sequestration, hence a global carbon pool. In order to mitigate the global climate change impact, the Kyoto protocol developed the clean development mechanism (CDM) which supports carbon credits for plantation activities in developing countries. Unfortunately, none of the CDM forestry projects included bamboo as a carbon reservoir. Although bamboo is an integrating part of tropical forest ecosystems, it was overlooked in the initial negotiating process. The present study, therefore, investigated the carbon storage potential of a common bamboo species, Bambusa vulgaris at Lawachara forest reserve of Bangladesh. Results showed that five-year-old B. vulgaris stand stored in total 77.67 t C ha−1 of which 50.44 t C ha−1 were stored in the above ground biomass (culms, branches and leaves), 2.52 t C ha−1 in the below ground biomass and 24.71 t C ha−1 in the soils. This amount of carbon storage is much more promising than the carbon storage of many other tree species considered in the CDM projects. These findings demonstrate the potential of B. vulgaris to be considered in CDM projects as a plantation species and thereby mitigate climate change impact more efficiently.  相似文献   

12.
Forest fragmentation is continued to be widespread in the tropics resulting in reduced ecosystem services including carbon storage. However, the effect of forest fragmentation is not considered in the current carbon policy. We investigated the effect of forest fragmentation on tree biomass carbon and soil organic carbon (SOC) storage in a moist tropical forest in Bangladesh. Above and below-ground tree biomass carbon were calculated by using widely accepted allometric equations and SOC was measured by sampling soils up to 10 cm depth and analyzing them in a soil laboratory. Results showed that carbon storage in tree biomass was significantly lower in fragmented forests (16.3 ± 1.37 t C ha−1) than in contiguous forests (31.21 ± 2.75 t C ha−1) (p < 0.001). Likewise, a significantly lower SOC was contained in the soils of fragmented forests (17.26 ± 0.83 t C ha−1) than in contiguous forests (21.62 ± 0.78 t C ha−1) (p < 0.001). Thus a total of 36% less carbon retained in tree biomass and soils in fragmented forests than in contiguous forests. Backward multiple linear regression analysis revealed tree density, tree height, tree DBH, height-diameter ratio (H/D) and tree species richness as influential factors of carbon variation in fragmented forests. All these structural parameters except tree species richness were significantly lower in fragmented forests, were positively associated with carbon storage and explained together 69% of the carbon storage variation. These findings suggest that the altered stand structure and tree allometry likely caused reduced carbon storage in fragmented forests and highlight the importance of landscape scale management intervention in the tropics. Here, we provided with the evidence of strong negative impact of forest fragmentation on carbon storage and argue that this effect should be in consideration which is currently overlooked in existing carbon accounting systems for tropical forests.  相似文献   

13.
以木材产品贸易对林业的影响为核心,对木材产品的进口和出口情况进行详细的统计分析,并运用弹性理论分析林业产值对木材产品进口和出口的敏感度,以此来初步证明木材产品贸易对林业的影响。研究表明,原木、锯材、刨花板、木家具、纸和纸制品的进口敏感度均高于木材总产品的进口敏感度1.382,尤其以刨花板和木家具的敏感度最大,为136.018,说明这些产品的进口额变化对林业产值变化的影响非常显著,进口额增加1%,将使林业产值成倍地增长。  相似文献   

14.
Increased forest areas and climate change mitigation are policy goals enhanced by expanding private forest ownership. This study shows transfer of land from farms owning forested acreage associated with low quality land and high production costs achieves such goals. Calculated cost efficiency scores show a large gap between the most and least efficient farms, and farms with forests are less cost efficient. Land reforestation through subsidy programs could replace income from agricultural production. We illustrate that farms from the applied FADN panel could reforest 45,000 hectares, binding about 0.5 mln tons of carbon annually without limiting food or feed supply.  相似文献   

15.
To assist pest management planning, the Canadian Forest Service developed the Spruce Budworm Decision Support System (SBW DSS), which quantifies the timber supply impacts of protecting stands against spruce budworm (Choristoneura fumiferana Clem.) defoliation. We incorporated protection costs and timber product values in this system to evaluate economic aspects of spruce budworm control. The analysis allows pest managers to evaluate the degree to which the traditional volume protection priority objective corresponds to three economic criteria, namely the volume protected per dollar protection program cost, the benefit–cost ratio of the protection program, and the net present value of the protection program. Twelve alternative spruce budworm protection strategies were analyzed on Crown License 1 in New Brunswick and Prince Albert Forest Management Area (PAFMA) in Saskatchewan, based on a number of protection program extents and intensities. For both landbases under base-case market conditions, the largest, most intensive protection scenario provided the highest amount of volume saved and net present value (at 3.94 Mm3 and $39.98 M for PAFMA, and 4.04 Mm3 and $41.49 M for License 1, respectively) while smaller, less-intensive programs provided the highest benefit–cost ratios and volume protected per present value dollar of protection cost (at 8.22 and 0.52 m3/$ for PAFMA, and 10.26 and 0.65 m3/$ for License 1, respectively). Sensitivity analysis on product values and protection costs revealed that smaller, less-intensive programs could also produce the highest net present values when costs are higher and/or product values lower. These results highlight the conditions under which pest managers should consider deviating from their traditional strategy of maximizing volume saved to one that maximizes the economic returns of protection.  相似文献   

16.
Objectives(1) To quantify the contribution of the French forest-wood product chain in terms of carbon sequestration and substitution when accounting for both the physical impacts (shifts in tree growth and mortality rates) and the market impacts (increased demand of harvested wood products (HWP)) of climate change (cc) and the subsequent forest managers adaptations; (2) To assess the uncertainty of the impacts on the above carbon balance and on forest allocation; and (3) To assess the role of managers’ expectations toward these future, uncertain but highly anticipated, impacts.MethodologyWe used a bio-economic model of the French Forest Sector (FFSM++) that is able to consider and integrate: (a) the effects of climate change over forest dynamics; (b) forest investment decisions (among groups of species) according to expected profitability; and (c) market effects in terms of regionalised supply, consumption and trade of HWP, depending on the forest resource stocks and international prices. By including both forest dynamics and forest products, we can evaluate the carbon balance taking the following elements into consideration: (a) carbon sequestered in live and dead biomass in the forest; (b) carbon sequestered in HWP; (c) carbon substituted when wood is used in place of fossil fuels or more energy-intensive materials; and (d) carbon released by forest operations.ResultsWhen the model is run at constant conditions for the next century, the average carbon potential of French forests is 66.2–125.3 Mt CO2 y−1, depending on whether we consider only inventoried wood resources, HWP pools and direct energy substitution, or if we also account for the carbon stored in tree branches and roots and if we consider the more indirect, but also largely more subjective, material substitution. These values correspond to 18.3% and 34.7%, respectively, of the French 2010 emissions (361 Mt CO2). However, when we consider both the probable increment of coniferous mortality and changes in forest growth, plus the rise in HWP demand worldwide, the average sequestration rate of the French forest decreases by 6.6–5.8% to 61.8–118.0 Mt CO2 y−1. Running partial scenarios, we can assess the relative interplay of these two factors, where the price factor increases the HWP stock while decreasing the forest stocks (where the latter effect prevails), while the physical impact of climate change reduces both, but to a lesser extent. Considering short-sighted forest managers, whose behaviour is based uniquely on the observed conditions at the time decisions are made, we obtain a limited effect of the overall carbon balance but a relatively large impact on the area allocation of broadleaved vs. coniferous species.  相似文献   

17.
2011年第四季度我国林业企业景气指数再次下降,也显著低于全国企业同期景气指数。第四季度出口上升,进口下降。出口商品主要以木竹家具、木竹制品、胶合板、纤维板为主,占主要林产品出口额的95.10%;进口商品主要以原木、锯材、木竹浆、废纸、木片等为主,占主要林产品进口额的96.32%。林产品进出口以龙头企业为主,整体同比增长,环比下降。分析了位列进出口前50家企业的状况及企业景气指数下降的主要原因。  相似文献   

18.
Land use and cover (LUC) change is a major driver of ecosystem service loss worldwide. In response, policymakers have designed conservation strategies that incentivize the establishment and maintenance of LUC types associated with higher ecosystem service provision. Many of these policies also aim to promote social and economic goals such as reducing poverty. Attempts to measure the impact of policy-driven LUC change on stakeholders typically focus only on economic outcomes for landowning participants or aggregate the socio-economic outcomes of diverse groups. In this study, we applied local ecological knowledge (LEK) held by beekeepers in Costa Rica to understand the impact of policy-driven LUC change on this specific group of often non-landowning stakeholders. Beekeeping is a globally important rural livelihood and provides pollination services to crops and wild plants. We synthesized beekeeper LEK using a mixed-methods approach including apiary mapping exercises (n = 215 apiaries), questionnaires (n = 50 participants), and follow-up interviews (n = 21 participants). Our study revealed that some policy-driven LUC changes have limited beekeepers’ access to preferred land uses, such as secondary and mature forests with native trees. Participants reported concern for their livelihoods due to policy-driven spatial and temporal change of floral resources via the establishment of tree plantations, changes in pasture management, and laws that prohibit beekeeping in national parks and reserves. Our study provides evidence of unintended outcomes from land use policies, including Payment for Ecosystem Services, with disproportionate negative impacts on non-landowning residents who depend on natural resources in the landscape for their livelihoods. Our study illustrates potential inequality rising from current incentive mechanisms associated with Payments for Ecosystem Services and other conservation policies and calls for policymakers to consider LUC change impacts on non-landowning stakeholders.  相似文献   

19.
运用产品相似性指数、市场相似性指数和显示性比较优势指数,分析中国与德国、意大利、马来西亚、波兰和越南等木质家具主要出口国在国际木质家具市场上的竞争关系,结果表明:中国与越南、马来西亚木质家具出口的市场相似度很高,但产品相似度较低;中国与意大利、波兰木质家具出口的市场相似度较低,产品相似度较高;意大利、德国木质家具产业的比较优势相对较弱且在萎缩,而波兰木质家具的比较优势极强。针对中国与木质家具主要出口国的这种竞争关系,提出中国木质家具产业应将低端产能逐步向东南亚国家转移,承接意大利、德国的家具产业转移,并积极应对波兰的竞争等对策建议。  相似文献   

20.
基于2008—2017年中国与常年贸易伙伴国的数据样本,运用面板数据估计方法分别测算了国产原木、锯材与进口原木、锯材之间的Armington替代弹性,并分三阶段分组检验,还测算了中国原木、锯材主要进口来源国的出口产出弹性。结果显示:国产原木、锯材与进口原木、锯材之间具有较低的可替代性,且可替代性均呈下降趋势;内外材差异化程度较大,对国外进口木材具有长期的进口依赖性;原木进口市场供给风险较大,新西兰、澳大利亚供给安全性强,美国、巴布亚新几内亚、俄罗斯进口风险大;锯材进口市场的供给较稳定,泰国、巴西和马来西亚等国供给潜力大。因此,中国应大力发展培育国内优质大径材和珍贵树材,建设培育基地,提高优质木材供给能力;寻找珍贵木材的替代材料,通过技术开发生产替代产品;加强境外森林资源的开发利用,调整木材进口来源,减少对高风险国家的进口依赖。  相似文献   

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