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1.
The history, current situation, and development trend of GIS (Geographic Information System) applied in the forest resources management were discussed in this paper. On the basis of geographic spatial characteristics of forest resources data, a component geographic information system (ComGIS) was developed for forest resources management. The system embeds a GIS ActiveX control MapObjects (Inc. ESRI) on Visual C platform. System design, data organization and achieving way were studied and expatiated by taking Xigangzi Forestry Centre as study object. The system has many useful functions,, such as adding and display of various map layers, zoom of map by wheeling mouse, attribute and spatial data querying, map auto roaming, features rendering based on the spatial trait of data, label controlling through attribute data band with vector graph, as well as output of ‘Column chart‘ for showing the result of statistics. At the same time, parts of source codes are attached.  相似文献   

2.
Across Europe, ungulate numbers have greatly increased over the past decades, leading to increasing concerns about the ecological and economical impacts and pleas for stronger population control. However, focussing on population control only ignores other underlying factors which may enhance the wildlife–forestry conflict. I reviewed factors which shape herbivore top-down effects in natural temperate forest systems aiming at understanding how these interactions are altered in managed forests. Carnivores are important in modifying ungulate–plant interactions. They can directly influence the numbers of ungulates, but this effect is dependent on productivity and predicted to be smallest in highly productive temperate forest. Indirectly, they modify herbivore top-down effects by creating a landscape of fear. Despite the abundance of knowledge from American systems, there is a lack of knowledge on how this process might work in European systems. Next to carnivores, abiotic conditions interact with herbivory by influencing forage quality and availability. Forest gaps lead to concentration of ungulates and their effects, due to increased forage supply. Abiotic conditions also influence the response of plants following herbivory, which can be tolerated by showing increased regrowth or resistance due to chemical or physical defence. In typical managed forest systems, carnivores and abiotic conditions which shape ungulate top-down effects in natural forests are altered or absent. Human hunting might replace the direct effects of carnivores, but does not replace their indirect effects. Forestry practices also have modified herbivore–plant interactions in several ways, creating a forest with lower ungulate carrying capacity and higher sensitivity for ungulate browsing. These changes logically increase the strength of herbivore top-down effects in managed forests and increase the wildlife–forestry conflict. To reduce this conflict, aiming only at reducing wildlife numbers is predicted to have little effects when they do not coincide with habitat ameliorations. Forestry practices may therefore greatly enhance the conflict that exists between wildlife and forestry but can also be an important tool to reduce this conflict by adapting management practices that allow more natural functioning of forests systems.  相似文献   

3.
IntroductionForestisakindofmulti-function'resourcethatcanbesustaininglyutiIized,butsomeprobIems,suchasinsufficiencyoftimberyieId,soiIerosion,cIimateim-baIanceinpartdistrictetc.,oftenarousedbecauseofincorrectuseandmanagementofnaturalresources.InordertodevelopthefOrestry,IotsoffOrestrypoIi-cieshavebeenissuedandcarriedout.V8rioustypesofforestresourcesmanagementhavebeenaroused,especialIycollectiveforestareasinsouthChina.However,whydiff6rentefficiencies,good,badandworse,eventoresultinthedecrea…  相似文献   

4.
In the recent 20 years, it is a trend that forest will be distributed to villagers to manage in the world. Also in China, “forestry three determinations” has been carried out since 1980, and many new forestry devolutions have been put forward to and come into being. To face the fact of overusing up natural forest to result in the deterioration of ecology environment, the strategy of natural forest protection project (NFPP) is raised after the heavy flood in 1998. Now, it is paid close attention to systematically study to carry out the strategies of NFPP in collective forest area, especially in the community of minority nationalities. Based on the case of forest resource management in Datu Miao Village, the experience of its forest management in the past is analyzed and the strategies of NFPP in collective forest area are put forward. Foundation item: This project is a part of research project “forest devolution management of IFAD/CIFOR” Biography: L{upuo} Ming-can (1961-), maie, associate professor, vice director of post-graduate school of Southwest Forestry College, Kunming 650224, P.R. China. Responsible editor: Song Funan  相似文献   

5.
Using plant community analysis methods, we analyzed the floristic characteristics, species composition, community structure, population structure, and spatial distribution patterns of a Betula dahurica forest on the “1238” mountain of Badaling in Beijing, China. The results show that: 1) There are 33 plant species in the B. dahurica community, including 18 woody plant spe- cies. The B. dahurica forest is a monodominant community with 75.9% dominance. 2) Based on diameter at breast height (DBH) size class distribution, the population structure of B. dahurica and Acer mono—two heliophyllous and pioneer tree species—is cascade-type, with both in an increasing stage. The population structure of Tilia mandshurica and T. mongolica, two shade-tolerant tree species, is inverse-J type, and they have more young seedling individuals and regenerate more stably. They are associated species of the pioneer tree species. The population structure of Quercus mongolica, as the associated species of climax species in the community, is sporadic, and its regeneration is fluctuating and random. Fraxinus rhynchophylla is a shade-tolerant tree species which has a unibar population structure and climax characteristics of pioneer tree species. The relative frequency of young seedlings reached 0.4. 3) The dominant species B. dahurica is still in an increasing stage, and the regeneration of other species is steady or partly influences the community, putting the community in the pioneer species stage. From the population structure and distribution frequency of F. rhynchophylla, the B. dahurica forest will approach to a climax state in the future.  相似文献   

6.
The forest estate in south-west Zabaikalia, a territory included in the Lake Baikal catchment area, has been investigated. For this purpose we have used both data of our own studies and monitoring data of environmental protection bodies. It shows that in our study area, fires, fellings, entomo-parasites and air pollution are the major negative factors affecting the state of the forest. In the period from 2003 to 2008 fires were registered in the area of over 500 thousand ha, pest foci in the forests covering an area of over 330 thousand ha, where almost 5 million m3 wood was cut in an area of about 43 thousand ha. The total area of forests in our study affected by air pollution amounts to about 700 thousand ha. According to the results, forest pollution in the territory is concentrated in the vicinity of large-scale industrial complexes, for distances up to about 40 km. The total area of forests weakened by air pollution amounts to about 2 million ha.  相似文献   

7.
The evaluation of ecosystem health has become one of the main research topics of ecosystem science, thus more and more assessment methods and frameworks have been put forward in recent years. However, the attention people pay to ecosystem health is actually more about what the social functions the ecosystem affords, which depend on the integrity and maintenance of the ecosystem structure and function, and the intensity of disturbance from outside. Accordingly, this research commenced from three main aspects, selected the evaluation indices, and then established the Evaluation Index System of Beijing Forest Ecosystem Health (EIS-BFEH). In the EIS-BFEH, each of the three foundations contained an easily-operated and standard sub-index system, which compounded the specific natural and social conditions of Beijing and was concrete enough to measure and evaluate. Then with the method of the Analytical Hierarchy Process (AHP), the comprehensive index (CI) could be obtained, which represented the health of the forest ecosystem. As a case study, the forest ecosystems in the Badaling area were sampled, evaluated, compared and ranked by use of the EIS-BFEH. The result show that the health of natural forests is much better than that of plantations in the Badaling forest center: the average comprehensive index of the former is 7.9, while the latter is only 6.6. From the results, it could also be found that there are nine units in the healthy state, two units in the subhealthy state, and only one unit of Robinia pseudoacacia in the morbid state.  相似文献   

8.
We used an integrated approach to analyze the influence of silvopastoral management on the biotic and abiotic factors influencing on the natural recruitment of native forests in Tierra del Fuego (Argentina). The probabilities of transition from flowers to seeds to seedlings were estimated in forests with silvopastoral management (i.e., stands that had been both grazed and thinned), secondary growth stands, and unmanaged old-growth areas. Pre-dispersal losses were caused by microclimate and insect predation acting on flowers and immature fruits. Post-dispersal losses resulted from the impact of reduced litterfall and microclimate. But the most critical stage of the overall cycle was seedling establishment. Silvopastoral practices and stand age modified the main drivers of regeneration. While flowering was unaffected by management, fruiting and seed production were more successful in unmanaged forests. Seedling establishment and survival were favored by canopy cover reduction in silvopastoral stands. The increase of solar radiation and soil moisture in managed forests positively influenced the seedling establishment and survival, while in second-growth forests it was limited by suitable micro-site availability. Thinning practices aimed at increasing the understory heterogeneity in mature forests and restoring canopy complexity of second-growth stands could be suitable for sustainable management of these temperate forests.  相似文献   

9.
The interest intermediation system has always attracted the attention of forest policy scientists. However, research on this subject has focused on the national level, despite the fact that forest issues are increasingly prominent on international and European agendas, both in the EU and the Pan-European Process on the Protection of Forests in Europe. Accordingly, the impacts of the globalisation and Europeanisation of forest policy and the peculiarities of multi-level policy processes have not been sufficiently taken into account. This article examines how international forest politics and the integration of national actors in the EU multi-level system of joint decision-making affect national actor constellations. To this end, I draw on the advocacy coalition framework to depict the Austrian forest policy network and its actors’ dispute on forest certification, as well as on hypotheses and empirical results of multi-level governance scholars and on my own preliminary results to investigate the likely effects of the evolving EU forest policy. The discussion provides some hypotheses and indications that national forest policy networks might be subject to significant change.  相似文献   

10.
By late 2017, governments had pledged more than 140 M ha to the global forest landscape restoration (FLR) agenda. Although much FLR will consist of conventional ecological restoration, a substantial proportion will involve agroforestry. The question therefore arises of how the agroforestry germplasm needs of FLR can be met, particularly given its emphasis on species diversity. This paper examines the role of market-based germplasm supply systems. A simple analytic framework is presented, and key demand- and supply-related factors are described. It is suggested that seedling supply and demand at market prices will not necessarily coincide with needs of all farmers nor with the requirements of a particular restoration program, and that market-based germplasm supply systems will therefore often not meet the needs of restoration programs. Implications of these findings are then identified and appropriate responses are suggested. These include those intended to produce shifts in demand or supply curves through addressing the underlying enabling environment, and direct subsidies to tree planting stock prices.  相似文献   

11.
Models for predicting mortality in even‐aged stands were developed. The models rely on data from the Norwegian National Forest Inventory, and were designed for use in large‐scale forestry scenario models. A two‐step modelling strategy was applied: (1) logistic regression models predicting the probability of complete survival occurring,” and (2) multiplicative regression models for stem number reduction and diameter calibration. A joint model for all species predicting the probability of survival occurring on a plot was developed. Separate models for forests dominated by spruce, pine and broadleaved trees were developed for stem number reduction, while no appropriate models for diameter calibration were found. The phenomenon mortality is a stochastic, rare and irregular event, and this was reflected as low R 2 in the models. However, the model performance appeared logical and the results of validations based on independent data were reasonably good, i.e. the presented models may be applied to large‐scale forestry scenario analyses. With new rotations of permanent sample plot measurements, the models should be evaluated and, if necessary, revised.  相似文献   

12.
Abstract

Similar to other industrialized countries, the USA has experienced a significant increase in the number of non-industrial private forest (NIPF) owners as well as shifts in the values held by these owners. This study examines the motivations of predominantly new ex-urban forest owners interested in forest management in pursuing collective action through participation in the now out-of-business Sustainable Woods Cooperative (SWC). While common elsewhere, forest landowner cooperatives in the USA are an anomaly. Through a case-study design that depended primarily on semi-structured interviews, it was found that SWC members were motivated to join SWC as it was an attractive alternative to (1) the typical timber sale scenario that often places the forest owner at a disadvantage, and (2) the primary government tax incentive program. SWC represents a shift towards owners playing a greater role in shaping forest practices and markets, which is generally absent in the USA. It also suggests that new ex-urban forest owners, who are found in most industrialized countries, will seek to reshape the forest policy arena to meet their values and objectives. As such, this study provides insights for others in understanding the potential changes wrought by the changing characteristics of forest owners.  相似文献   

13.
IntroductionKoreanpine(PinuskoraiensiSSieb.etZucc.)forestmixedwithbroad-leavedtreesisacIimaxvegetationtypeinNoFtheastChina(Wang1994;Nie1995iZhOu1994).BecausetheforestdominatedbyPinuskoraiensiSthathasveryhighecologicaIandeconomicvalue(Wang1994,Nie1995lZhou1994),itisoneofthemostcompIicatedplantcommunitytypesinNoFtheastAsia.ThisforestisveryimpoFtantforthemaintenanceofbiodiversityandtheconserva-tionofwaterandsoiIintheregionalarea(Liu1957,Zhang1957,Zhang1986,JiLin199O,Wang1994,Nie1995)…  相似文献   

14.
Conversion of natural secondary broad-leaved forest to Cunninghamia lanceolata plantation is a common management practice in subtropical China. In this study, we compared soil physico-chemical properties, microbial biomass in one natural secondary broad-leaved forest and two C. lanceolata plantation sites to estimate the effects of forest conversion on soil microbial biomass at the Huitong Experimental Station of Forestry Ecology, Chinese Academy of Sciences. Concentrations of soil organic carbon, total nitrogen, NH4^+-N and microbial biomass carbon and nitrogen were much lower under C. lanceolata plantations as compared to natural secondary broad-leaved forest. Soil microbial biomass C in the first and second rotation of C. lanceolata plantations was only 53%, 46% of that in natural secondary broad-leaved forest, and microbial biomass N was 97% and 79%, respectively. The contribution of microbial biomass C to soil organic C was also lower in the plantation sites. However, the contribution of microbial N to total nitrogen and NH4^+-N was greater in the C. lanceolata plantation sites. Therefore, conversion of natural secondary broad-leaved forest to C. lanceolata plantation and continuous planting of C. lanceolata led to the decline in soil microbial biomass and the degradation of forest soil in subtropical China.  相似文献   

15.
The Great Xing’an Mountains boreal forests were focused on in the northeastern China.The simulated future climate scenarios of IPCC SRES A2a and B2a for both the baseline period of 1961-1990 and the future scenario periods were downscaled by the Delta Method and the Weather Generator to produce daily weather data.After the verification with local weather and fire data,the Canadian Forest Fire Weather Index System was used to assess the forest fire weather situation under climate change in the study region.An increasing trend of fire weather severity was found over the 21st century in the study region under the both future climate change scenarios,compared to the 1961-1990 baseline period.The annual mean/maximum fire weather index was predicted to rise continuously during 2010-2099,and by the end of the 21st century it is predicted to rise by 22%-52% across much of China’s boreal forest.The significant increases were predicted in the spring from of April to June and in the summer from July to August.In the summer,the fire weather index was predicted to be higher than the current index by as much as 148% by the end of the 21st century.Under the scenarios of SRES A2a and B2a,both the chance of extremely high fire danger occurrence and the number of days of extremely high fire danger occurrence was predicted to increase in the study region.It is anticipated that the number of extremely high fire danger days would increase from 44 days in 1980s to 53-75 days by the end of the 21st century.  相似文献   

16.
Forest certification can be conceived as one of many rapidly growing non-state market driven (NSMD) modes of governance. The environmental effectiveness of forest certification is oftentimes evaluated by indicators such as stringency of standards, degree of participation by key stakeholders, certified area, etc. In political science, forest certification as an NSMD governance arrangement is usually evaluated in terms of the quality of the decision-making procedures (input legitimacy) rather than for its problem solving capacity, i.e. its environmental performance or effectiveness. We conceptualize environmental effectiveness as a function of a standard's environmental stringency and the area covered by the standard, the latter dependent on the degree of social acceptance. Accordingly, the environmental effectiveness of different certification schemes ought to be evaluated taking both the standard stringency and the area certified into account. The forest certification process in Sweden illustrates how forestry history and regional differences affect the development, acceptance and adoption of different certification schemes. Industrial and Northern forestry owners favour the NGO led Forest Stewardship Council (FSC) standards whereas Southern small-scale private forest owners preferred to develop an alternative scheme the Programme for Endorsement of Forest Certification (PEFC). We demonstrate that there is a bifurcated geographical coverage of the two certification schemes along a north–south divide coupled with a similarity in standard stringency and a high degree of acceptance in their different areas of dominance. Both forest certification schemes display a similar degree of environmental effectiveness — but in different parts of the country and for different types of ownership.  相似文献   

17.
ABSTRACT

In forest insurance policy, coverage level and premium subsidy are two important factors that affect farmers’ decision to be insured. This paper uses data from a survey of farmers in Hunan Province of China. First, a single-bounded dichotomous-choice valuation method is used to estimate the average amount that the farmers are willing to pay (WTP) for forest insurance. The results show that farmers’ average WTP is 0.65 RMB/acre (Chinese currency is referred as RMB), which is lower than the premium level prescribed in the existing forest insurance implementation program. Second, an acreltiple-bound dichotomous-choice valuation method is used to study farmers’ WTP for acreltiple coverage levels. Results show that when coverage equals 500 RMB/acre, 1,000 RMB/acre, and 2,000 RMB/acre, the median value of the premium level of farmers’ WTP is 0.922 RMB/acre, 1.954 RMB/acre and 2.893 RMB/acre, respectively. In a situation where the current premium rates are unchanged, and the coverage level is 500 RMB/acre, 1,000 RMB/acre, or 2,000 RMB/acre, the models predict the subsidy ratio should be 53.90, 51.15 and 63.84%, respectively. Improving the coverage level of existing forest insurance policies can significantly increase farmers’ expected rate of insurance.  相似文献   

18.
Roots and rhizosphere soils of Acacia auriculiformis A. Cunn. ex Benth., A. mangium Wild., Artocarpus heterophyUus Lamk. C., Dalbergia sissoo Roxb. ex A. P. D., Eucalyptus camaldulensis Dehnn., Hevea brasiliensis (Wild. ex Juss) Muell. Arg., Swietenia macrophylla King. and Tectona grandis L. were collected from different locations of Madhupur forest area to study the biodiversity of Arbuscular Mycorrhizal (AM) fungal colonization and spore population. All the plants showed AM colonization. Out of eight selected plants, mycelial colonization was lowest in the roots of A. heterophyllus (22%) and the highest was in the roots of H. brasiliensis (78%). Mycelial intensity was observed poor (25%-77%) and moderate (23%-57%) in all plants species and abundant (11%-40%) was in most of the plant species. Vesicular colonization was observed in five plant species. The lowest was recorded in E. camaldulensis (4%) and the highest was in H. brasiliensis (21%). Poor (24%-56%), moderate (16%-100%) and abundant (11%-40%) type of vesicular intensity were observed. Arbuscular colonization was observed in three plants. The highest was in A. mangium (72%) and the lowest was in S. macrophylla (17%). Arbuscular intensity was recorded as poor (12%-44%), moderate (22%-100%) and abundant (4%-47%). The highest AM fungal spore population was in A. auriculiformis (714) and the lowest was in D. sissoo (102). Five AM fungal genera were recorded. Glomus was found to be dominant. A few spores remained unidentified. Significant correlation was observed between percent coloniza- tion and spore population. The results of the present study indicate the occurrence of AM fungi and the mycotrophism of the plants of Madhupur forest area and the applicability of AM technology in the forest management of Madhupur forest.  相似文献   

19.
This paper presents a method for complex evaluation and quantification of tree-layer species diversity in forest ecosystems—model BIODIVERSS. The model was constructed for the assessment of species diversity on a small-scale (forest-stand) level, but may be applied with advantage to regional and large-scale inventories. The probability of correct classification of species diversity degree is relatively high; e.g. with a sampling intensity of only 1.5%, the correctness of the classification by the model is already 90%. Model BIODIVERSS is a simple and practical tool. It can be used directly during fieldwork, since for its application only a pocket calculator is needed.  相似文献   

20.
吴俊民  吴保国 《林业研究》2000,11(2):103-105
lntroductionConcerningthemechanismoftheinteractionbe-tWeentreespeciesinthelarch(LafisgmelinI)-ash(PraxiPusmandShuFbe)mixedforest,wehavestudiedtheaIIelopathiceff6ctsoftheIarchvolatilematter,litterandrootsecretion.onthegroWthofash.TheobtainedresultsshowedclearIythatthelarchvoIatiIematt6rplayedaninhibitivepart,andboththeIarchIitt6randrootsecretionpIayedanobviousfystimuIatingpaFtontheashgroWth(Wu2oooa,2ooob,2oooc).Thispapermakesastudyofanotherallelo-pathicway(Ieaching)betWeenlarchandash.T…  相似文献   

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