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文章分年度、森林起源、森林权属、森林类别、采伐类型统计了广东省“十三五”期间的林木采伐消耗蓄积量,分析了期间的森林采伐限额执行情况,指出了期间的森林采伐限额方面的管理措施及存在的主要问题,并对“十四五”期间森林采伐限额的管理提出了意见和建议. 相似文献
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阐述实行森林采伐限额制度管理的必要性,分析曲靖市森林采伐管理的现状及存在的问题,对存在问题的原因进行分析,提出完善森林采伐限额管理制度的建议:调整森林采伐限额结构,进一步理顺保护、发展与合理利用的关系,改革和完善森林采伐管理政策,合理下达国有林采伐计划等. 相似文献
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森林采伐限额执行情况检查中发现的问题与对策 总被引：2，自引：0，他引：2
国家林业局每年组织四个直属林业调查规划设计院对全国森林采伐限额执行情况进行了检查,并对检查结果实行整改或全国通报,使全国森林采伐限额执行情况有了明显的好转,各级政府林木采伐管理水平有了很大的提高。但检查结果中发现,采伐许可证管理、伐区调查设计、伐区作业管理、森林采伐限额管理制度等方面仍然存在诸多问题,通过对问题的分析,提出解决的对策。 相似文献
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通过分析不同森林类型采伐的经营特点,探讨森林采伐限额政策的适宜程度,形成对部分类型森林放开采伐限额的思路,分析评估放开采伐限额政策的风险,提出改善森林采伐限额政策建议。 相似文献
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绵阳市森林采伐限额管理监督检查与分析 总被引：1，自引：0，他引：1
通过对绵阳市1996年森林采伐限额管理监督检查,反映该市森林采伐限额管理执行情况、采伐限额管理制度和降低消耗的经验、存在的主要问题和改进措施。 相似文献
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森林采伐限额管理中存在的问题与对策 总被引：1，自引：0，他引：1
俞培忠 《中南林业调查规划》2000,19(3):7-9
通过对华东监测区某省８个县森林采伐限额执行情况的调查，对限额管理中存在的超证采伐、无证采伐等问题进行分析，指出存在问题的原因，提出对策与建议。 相似文献
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通过剖析森林采伐限额本身的科学性和合理性对林木采伐管理的影响,论述了加强"源头"管理、实行凭证采伐是执行森林采伐限额的关键所在,分析了无证采伐存在的形式及其对限额采伐的影响,并提出了相应的管理措施。 相似文献
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森林采伐限额执行中存在的主要问题及对策 总被引：6，自引：1，他引：5
实行森林采伐限额制度是控制森林资源消耗的有效手段。依据近两年全国森林采伐限额执行情况检查结果材料,分析了林木采伐管理、伐区凭证采伐制度执行方面存在的问题,提出了解决措施。 相似文献
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从三明市的实际出发,对林木采伐限额和木材生产计划、林木采伐指标分配、天然商品林采伐管理、自然灾害林木采伐四方面存在的问题进行了分析,并提出了有针对性的建议,旨在为科学制定森林采伐限额提供决策依据。 相似文献
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森林采伐限额制度是森林采伐管理的重要内容,其目的是通过对森林采伐数量来控制森林蓄积量。本文在总结了森林采伐限额制度存在的问题的同时,提出了完善该项制度的意见。 相似文献
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分别采用SPOT5、TM5影像前后两期多光谱遥感影像的波谱特征变化,检测森林资源变化信息,确定变化类型,以计算机自动识别对森林资源变化(减少)的区域(伐区)进行信息提取,并在此基础上进行室内人工预判读;结合采伐证、伐区作业设计、二类调查材料,进行补充判读,得出森林采伐图斑。古丈TM5(30 m分辨率)的面积正判率为96.3%;古丈SPOT5(10 m分辨率)的面积正判率为96.9%。实证分析表明,使用中、高分辨率卫星遥感数据能对森林采伐进行监测,结合辅助材料后能显著提高森林采伐监测精度。 相似文献
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论红松果材林的生态经济问题 总被引：1，自引：0，他引：1
本文全面主红松果材林生态系统的特点,划分了吉林省红松果材林的栽培区域。提出了红松果材林复合生态系统类型和红松果材林经营的技术问题。 相似文献
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森林土壤有机碳(SOC)是全球碳循环的重要组成部分,然而,多样的森林类型和不同森林经营措施的干扰,使得森林土壤碳库维持机制以及碳固存过程的研究和森林土壤碳库的估算存在较大的变异。作为主要的森林经营措施之一,采伐对森林土壤碳储量以及碳过程均产生直接或间接地影响。为深刻理解森林土壤碳库对于采伐干扰的响应,本文综述了近十几年来不同采伐方式下森林土壤碳储量及其主要碳排放过程——土壤呼吸的研究现状,综合分析了采伐方式、森林类型、采伐剩余物管理以及微生物因子等对土壤碳库的影响及其不确定性,并在此基础上阐述了研究中尚未解决的主要问题:1)生物因子作为CO2产生的主体,在应对干扰时结构、功能的变化直接影响着土壤碳排放以及碳固定,但它们具体作用机制以及过程并不清楚,需展开进一步的调查;2)不同森林采伐方式对不同地区和不同类型森林土壤的影响的复杂性,亟须在进一步加强实验研究的基础上,发展森林土壤碳循环的过程或机理模型,为森林生态系统完整的碳循环过程表达及碳计量提供技术支撑,以期为我国森林经营以及碳汇等方面研究提供参考。 相似文献
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Restoring altered forest landscapes toward their ranges of natural variability (RNV) may enhance ecosystem sustainability and resiliency, but such efforts can be hampered by complex land ownership and management patterns. We evaluated restoration potential for southern-boreal forests in the ∼2.1 million ha Border Lakes Region of northern Minnesota (U.S.A.) and Ontario (Canada), where spatially distinct timber harvest and fire suppression histories have differentially altered forest conditions (composition, age–class distribution, and landscape structure) among major management areas, effectively resulting in forest landscape “bifurcation.” We used a forest landscape simulation model to evaluate potential for four hypothetical management and two natural disturbance scenarios to restore forest conditions and reduce bifurcation, including: (1) a current management scenario that simulated timber harvest and fire suppression practices among major landowners; (2) three restoration scenarios that simulated combinations of wildland fire use and cross-boundary timber harvest designed to emulate natural disturbance patterns; (3) a historical natural disturbance scenario that simulated pre-EuroAmerican settlement fire regimes and windthrow; and (4) a contemporary fire regime that simulated fire suppression, but no timber harvest. Forest composition and landscape structure for a 200-year model period were compared among scenarios, among major land management regions within scenarios, and to six RNV benchmarks. The current management scenario met only one RNV benchmark and did not move forest composition, age–class distribution, or landscape structures toward the RNV, and it increased forest landscape bifurcation between primarily timber-managed and wilderness areas. The historical natural disturbance scenario met five RNV benchmarks and the restoration scenarios as many as five, by generally restoring forest composition, age–class distributions, and landscape structures, and reducing bifurcation of forest conditions. The contemporary natural disturbance scenario met only one benchmark and generally created a forest landscape dominated by large patches of late-successional, fire-prone forests. Some forest types (e.g., white and red pine) declined in all scenarios, despite simulated restoration strategies. It may not be possible to achieve all objectives under a single management scenario, and complications, such as fire-risk, may limit strategies. However, our model suggests that timber harvest and fire regimes that emulate natural disturbance patterns can move forest landscapes toward the RNV. 相似文献
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Elevated nitrate concentrations in streams and groundwater are frequently observed following forest harvest. In addition to depleting nutrients available for forest regeneration, elevated nitrate export following harvest can have deleterious effects on downstream aquatic ecosystems. As part of a forest harvest experiment conducted at the Turkey Lakes Watershed, Ontario, Canada, stable isotope techniques were employed to investigate nitrate attenuation in a natural wetland receiving high concentrations of nitrate as a result of clear-cutting in the catchment. Isotopic analysis of nitrate (δ18O, δ15N) and vegetation (δ15N) demonstrated that both denitrification and plant uptake of nitrate resulted in significantly lower nitrate concentrations in wetland outflow compared to incoming stream water. Although the 0.2-ha forested swamp (4% of catchment by area) was too small to be featured on standard topographic maps, the wetland remove 65–100% of surface water nitrate inputs, thereby protecting downstream aquatic habitats from the full effect of N release from forest harvest. The δ15N enrichment factor associated with nitrate attenuation in wetland surface water was lower than typically observed during denitrification in groundwaters, suggesting that nitrate removal is complete in some areas of the wetland. Plant assimilation of nitrate was also partially responsible for the low observed enrichment factor. Wetland plants recorded the high δ15N associated with denitrification activity in portions of the wetland. Apportionment of nitrate sources using δ18O–NO3− at the outlet weir was unaffected by the wetland nitrate attenuation under pre- and post-harvest conditions due to the mid-catchment position of the wetland. Future forest management practices designed to recognize and preserve small wetlands could reduce the potentially detrimental effects of forest harvest on aquatic systems. 相似文献
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《Forest Policy and Economics》2001,2(3-4):213-228
Consequences for net present value, net income and harvest related to ‘sustainable forest management regimes’ at non-industrial forest owner level in Norway are discussed. The following indicators of a sustainable forest management have been analysed: existing old forest set aside for preservation, maintaining minimum target levels for area covered by old forest through time, restricted treatments for border zone areas around water bodies, retention of trees at final harvest and restricted options with respect to regeneration. The consequences were analysed according to individual as well as co-operative management for eight different properties. GAYA-JLP, a large scale forestry scenario model applying simulations and linear programming, was used for the calculations. A regime with a ‘medium’ intensity of the environmentally oriented constraints, and a real rate of discount of 2.5%, reduced the net present values by 8% to 20%. The results indicated that the consequences for individual properties might vary considerably if the regimes for a sustainable forestry are designed generally without considering the heterogeneity among the properties with respect to the initial forest state. Assuming co-operative management, the net present value of the entire forest area (all properties) increased. At the same time it was possible to increase, respectively, the proportion of old forest set aside for preservation and the area covered by old forest through time. The differences compared with individual management were relatively small for all these parameters, and most likely not large enough to cover up for the transaction costs related to co-operative management. Whether the gains of co-operation will exceed transaction costs, can probably only be answered through cost-benefit analyses of the actual project. 相似文献
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Ideal Point Method Applied in Forest Harvest Regulation 总被引：1，自引：0，他引：1
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In Maine and other heavily forested states, existing land cover maps quickly become dated due to forest harvesting and land use conversion; therefore, these maps may not adequately reflect landscape properties and patterns relevant to current resource management and ecosystem studies. By updating an older land cover product (the 1993 Maine GAP map) using Landsat imagery and established forest change detection techniques, we demonstrate a practical and accurate means of providing contemporary, spatially explicit forest cover data needed to quantify landscape change. For a 1.8 million hectares study area in northern Maine, we quantify the accuracy of forest harvest classes and compare mapped harvest and regeneration area between the 2004 GAP update product and the 2004 Maine Landcover Dataset (MeLCD), a map recently developed in coordination with the 2001 National Land-Cover Database (NLCD). For the period 1995–2004, the overall harvest/non-harvest accuracy of the GAP update map is 87.5%, compared to 62.1% for the MeLCD. Producer and user accuracy for harvest detection is 92.4% and 89.7%, respectively for the GAP update, and 48.8% and 92.5% for the MeLCD. Mapped harvest area differs considerably, reflecting a systematic under-representation of recent harvest activity on the part of the MeLCD. By integrating older land cover data, the GAP update retains the forest disturbance legacies of the late 1970s through the early 1990s while simultaneously depicting 2004 forest composition for harvested and regenerating stands. In contrast, the MeLCD (and 2001 NLCD) over-represents the area and connectivity of older forest (undisturbed since the late 1970s), and provides no forest composition information for mapped forest regeneration. Systematic misclassification of forest age classes and harvest history has serious implications for studies focused on wildlife habitat modeling, forest inventory, and biomass or carbon stock estimation. We recommend the integration of older land cover data and time-series forest change detection for retention of harvest or disturbance classes when creating new forest and land cover maps. 相似文献