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91.
封山育林形成了安徽省的天然次生林,主要有常绿针叶林、针阔混交林、落叶阔叶林、落叶常绿阔叶混交林、常绿阔叶林5种主要类型。天然次生林经营管理目标以"分类经营"、"近自然林业"和"多种效益"为理论,实现以保护为主,适度开发利用的可持续发展;经营管理原则是分类经营、合理地进行人为干扰、生物多样性保护;通过野外调查,对经营目标、原则进行综合分析、统筹决策,制定出合理的经营方案再根据次生林的类型和经营目标的不同,采取不同的经营管理技术。 相似文献
92.
Eugene L. Chia Didier Hubert Kevin Enongene Yitagesu T. Tegegne 《Journal of Sustainable Forestry》2020,39(4):379-391
ABSTRACTAs the role of forests in climate change mitigation is explicitly recognized in the Paris Agreement, the need to enhance the adoption of Sustainable Forest Management (SFM) practices is crucial. Therefore, this paper aims at identifying and evaluating barriers in adopting SFM practices in the context of forest carbon emission reductions. A total of 15 barriers in adopting SFM practices are listed through literature and expert inputs. Using Cameroon as a case study, the listed barriers are then evaluated by experts to determine their relative importance using the Analytical Hierarchy Process (AHP) method. According to our findings, the ‘Regulatory and Legislative frameworks’ barrier category was attributed to the highest importance among other categories, in adopting SFM practices in the forestry sector. ‘Inadequate political will and incentive to enforce regulations’ appears to be the major obstacle in adopting SFM practices in Cameroon. As carbon emission reduction initiatives are being developed, there is need to move from broad to concrete suggestions that will overcome these barriers. However, proper diagnosis is necessary in order to target barriers with the right incentives and enabling conditions that will support carbon programs and projects to deliver effective emission reductions. 相似文献
93.
建设稳定的林分是历代务林人所追求之目标,该文根据太行山区植被演替现存的稳定群落结构及近年来混交林建设的实践经验,提出了在太行山林业生态工程建设中混交林的营造模式及途径。 相似文献
94.
运用改良SDS(十二烷基硫酸钠)法,从马尾松、黄山松、黑松等松树种子胚乳中提取到较高纯度的DNA,并对其纯度、浓度及产率进行了分析.经RAPD检测表明,DNA扩增效果良好,完全能满足常规DNA实验的要求,为针叶树种等其它小粒种子DNA的提取提供了经济、快速、可靠的实验方法. 相似文献
95.
Carly Green Brian Tobin Michael O’Shea Edward P. Farrell Kenneth A. Byrne 《European Journal of Forest Research》2007,126(2):179-188
Reporting carbon (C) stocks in tree biomass (above- and belowground) to the United Nations Framework Convention on Climate
Change (UNFCCC) should be transparent and verifiable. The development of nationally specific data is considered ‘good practice’
to assist in meeting these reporting requirements. From this study, biomass functions were developed for estimating above-
and belowground C stock in a 19-year-old stand of Sitka spruce (Picea sitchensis (Bong) Carr.). Our estimates were then tested against current default values used for reporting in Ireland and literature
equations. Ten trees were destructively sampled to develop aboveground and tree component biomass equations. The roots were
excavated and a root:shoot (R) ratio developed to estimate belowground biomass. Application of the total aboveground biomass function yielded a C stock
estimate for the stand of 74 tonnes C ha−1, with an uncertainty of 7%. The R ratio was determined to be 0.23, with an uncertainty of 10%. The C stock estimate of the belowground biomass component was
then calculated to be 17 tonnes C ha−1, with an uncertainty of 12%. The equivalent C stock estimate from the biomass expansion factor (BEF) method, applying Ireland’s
currently reported default values for BEF (inclusive of belowground biomass), wood density and C concentration and methods
for estimating volume, was found to be 60 tonnes C ha−1, with an uncertainty of 26%. We found that volume tables, currently used for determining merchantable timber volume in Irish
forestry conditions, underestimated volume since they did not extend to the yield of the forest under investigation. Mean
stock values for belowground biomass compared well with that generated using published models. 相似文献
96.
Ian Jeffreys 《Small-Scale Forestry》2004,3(1):99-117
Small-scale farm forestry has the potential to offer many benefits both to landholders and the wider community. As with all
changes in land-use practices, there are associated benefits and costs and these are not uniformly distributed. They have
varying impacts on the different values, aspirations, goals and objectives that exist within the community. Furthermore, the
community does not consider these values, aspirations, goals and objectives of equal importance. The degree of concern can
vary from minor to high and overriding all other considerations. When evaluating farm forestry options it is necessary to
address all of these concerns. This paper examines the combined use compensatory and non-compensatory multi-criteria analyses
to evaluate forestry options, in a case study for the Darling Downs region of Queensland, Australia. These aggregation techniques
are found to be highly complementary and together provide a comprehensive analysis. The compensatory technique provides a
sound measure of overall performance of a forestry system, whereas the non-compensatory technique alerts decision-makers to
presence of particularly poor performance with respect to individual criteria. The compensatory technique used is simple and
understandable even for those with non-mathematical backgrounds. This analysis can identify and aid communication of the relative
benefits and costs, and trade-offs, between economic, environmental and social considerations. 相似文献
97.
FORESTAR:A decision—support system for multi—objective forest management in Northeast China 总被引:11,自引:0,他引:11
SHAOGuo-fan DAILi-min LIYing-shan LiuYong-min BAIGuang-xin 《林业研究》2003,14(2):141-145
Past monoculture forestry in China has contributed to countrywide ecological disasters and economic difficulties in forestry regions. China‘s new forestry programs, Natural Forest Conservation Program and Returning Farmlands to Forests Program, provide opportunities for ecosystem management of mountain forests in China. A decision support system, FORE-STAR, has been developed for better managing and protecting natural forests in Changbai Mountain area. It uses GIS-based forest inventory data at a scale of forestry bureau. The first version contains two sub-modules: forest operation and forest res-toration. Under each sub-module, users can compare several decision options and make optimal choices. It can help field for-esters, forest managers, and policy makers make multi-objective and consistent decisions in planning forest management at hierarchical administrative scales. 相似文献
98.
In order to meet the demands of modern, information-based society, higher education in natural resource management needs to be transformed. Enhanced mobility of students and staff, multi- and transdisciplinary approaches, as well as innovative educational approaches are called for. Moreover, the urban component needs to be better incorporated, as exemplified by the emerging field of urban forestry. This paper relates to the developments in higher education within the context of education on urban forests and urban trees in Europe. Presented here are the main findings of a comparative European study led by the Danish Forest and Landscape Research Institute within the framework of the EU-funded COST Action E12 'Urban Forests and Trees'. In order to obtain an overview of the status of higher education on urban forestry in Europe, 180 educational institutions in 28 countries were sent a questionnaire. Results show that urban forestry is an expanding element of European education, as urban elements are becom 相似文献
99.
KU Daping Bernie DELL. Research Institute of Tropical Forestry CAF Guangzhou China . Murdoch University. Perth. Australia 《中国林业科技(英文版)》2002,(1)
Eucalypts are very popular for revegetation in many parts of south China because of their capacity to tolerate degraded sites and unfertile soils,and their fast growth potential to coppice. This paper reviews a decade of field trials in china, undertaken as part of several bilateral researchprograms in plantation forestry, concerning the use of fertilizers, harvest residue management and inoculation with ectomycorrhizal fungi. One of the key questions addressed is whether the productivity of plantation eucalypts in south China can be increased to the world average by nutrient management across a rotation. 相似文献
100.
To derive optimal benefits from intercropping timber, farmers should make important initial decisions on tree species and
planting density with a good understanding of their tradeoffs. Complex and data-intensive models used by researchers should
be supplemented with simpler models based on easily measured parameters and easily understood competition functions. In experiments
in the Philippine uplands, growth parameters of three popular farm-forestry species (Eucalyptus deglupta, E. torelliana, and Paraserianthes falcataria) were measured, along with intercropped and non-intercropped yields of maize and vegetables. The commonly used forestry parameter
of stand basal area had a significant negative correlation with intercrop yields (as a percentage of non-intercropped yields).
The slope of the regression line differed between species; in this study, percent yield loss per unit stem basal area growth
was in the order E. deglupta > E. torelliana > P. falcataria. The relationship between stand basal area and intercrop-yield decline was tested on an independent data set from China.
Intercrop yields had significant negative correlations with stand basal area of Paulownia elongata. We propose that adaptive tree-screening trials evaluate competitiveness in addition to evaluating growth and mortality.
Stand basal area may be better suited to this task than more mechanistic indices such as leaf-area index as it is easy to
measure, calculate, and understand, and it may serve as a better index of total (aboveground + belowground) competition. Basal
area is also directly related to tree volume, and allows farmers to more easily evaluate the economic tradeoffs between tree
growth and intercrop-yield declines.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献