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1.
This paper examines the value of non-timber forest products (NTFP) and their determinants in communities in the vicinity of the Okwangwo Division of the Cross River National Park, Nigeria. The data for this study were generated from personal interviews conducted in three villages located near the buffer area of the national park. The study showed that income from NTFP was almost 13% of the total annual income of the respondents. Income from NTFP was influenced by factors such as income from non-traditional employment, the distance of respondents' residences to the park, income from farming and age. The results suggest that a shift from primarily subsistence to a more of cash economy may lead to unsustainable exploitation of NTFP.  相似文献   

2.
This paper examines the interaction of spatial and dynamic aspects of resource extraction from forests by local people. Highly cyclical and varied across space and time, the patterns of resource extraction resulting from the spatial–temporal model bear little resemblance to the patterns drawn from focusing either on spatial or temporal aspects of extraction alone. Ignoring this variability inaccurately depicts villagers’ dependence on different parts of the forest and could result in inappropriate policies. Similarly, the spatial links in extraction decisions imply that policies imposed in one area can have unintended consequences in other areas. Combining the spatial–temporal model with a measure of success in community forest management—the ability to avoid open-access resource degradation—characterizes the impact of incomplete property rights on patterns of resource extraction and stocks.  相似文献   

3.
4.
Monitoring agricultural products requires the periodic determination of land cover and the production of land use policies in an optimum way. The hazelnut is one of the important Turkish agricultural exports and Turkey provides 77% of the world's hazelnuts. In Turkey, hazelnut production exceeds the demand; new regulations have been enacted to create new land use policies. By putting into practice regulations restricting hazelnut plantation areas, a more efficient and productive hazelnut harvest policy could be created. Therefore, more information on existing land cover is required to determine optimum (or ideal) potential hazelnut areas (PHA) and to forecast future crop production. The principle aim of this study is to create a methodology for determining existing PHA, using Geographic information system (GIS) and remote sensing (RS) techniques regarding to support hazelnut policy developers and economists. This study was basically carried out in the province of Trabzon, which is one of the most important hazelnut production areas in Turkey. Landsat ETM+ image was used to generate a current land cover classification. Using the supervised classification method, overall accuracy was determined to be 84.7%. Suitable hazelnut areas were determined according to criteria settled by government regulations.  相似文献   

5.
Protected areas (PAs) represent a key global strategy in biodiversity conservation. In tropical developing countries, the management of PAs is a great challenge as many contain resources on which local communities rely. Collection and trading of non-timber forest products (NTFPs) is a well-established forest-based livelihood strategy, which has been promoted as a potential means for enhanced conservation and improved rural livelihoods in recent years, even though the sustainability or ecological implications have rarely been tested. We conducted an exploratory survey to understand the role and stakeholder views on conservation prospects and perceived ecological feasibility of NTFPs and harvesting schemes in a northeastern PA of Bangladesh, namely the Satchari National Park. Households (n?=?101) were interviewed from three different forest dependency categories, adopting a stratified random sampling approach and using a semi-structured questionnaire. The study identified 13 locally important NTFPs, with five being critically important to supporting local livelihoods. Our study suggests that collection, processing and trading in NTFPs constitutes the primary occupation for about 18% of local inhabitants and account for an estimated 19% of their cash annual income. The household consensus on issues relating to NTFPs and their prospective role in conservation was surprisingly high, with 48% of respondents believing that promotion of NTFPs in the PA could have positive conservation value. The majority (71%) of households also had some understanding of the ecological implications of NTFP harvesting, sustainability (53%) and possible management and monitoring regimes (100%). With little known about their real application in the field, our study suggests further investigations are required to understand the ecological compatibility of traditional NTFP harvesting patterns and management.  相似文献   

6.
Forest road construction by bulldozers in Calabrian Pine (Pinus brutia Ten.) forests on mountainous terrain of Turkey causes considerable damage to the environment and the forest standing alongside the road. This situation obliges a study of environmentally sound road construction in Turkey. This study was carried out in 4 sample sites of Antalya Forest Directorate in steep (34-50% gradient) and very steep terrain (51-70% gradient) conditions with bulldozer and excavator machine and direct damages to forest during road construction was determined, including forest area losses and damages to downhill trees in mountainous areas. It was determined that in steep terrain when excavators were used, less forest area (22.16%) was destroyed compared to bulldozers and 26.54% less area in very steep terrain. The proportion of damage on trees where bulldozer worked was nearly twofold higher than excavator was used. The results of this research show that the environmentally sensitive techniques applied for the road construction projects are considerably superior to the traditional use of bulldozers on steep slopes. The environmentally sound forest road construction by use of excavator must be considered an appropriate and reliable solution for mountainous terrain where areas of sensitive forest ecosystems are to be opened up.  相似文献   

7.
Medically used plant species in Eastern Black Sea Region of Turkey was determined in this study. Totally 50 species within 24 families have been designated in 25 research points, using the face to face polling method with the herbs sellers and purchasers. 14 species of studied plants are endemic and pointed out as endangered species according to the IUCN list (The World Conservation Union). In which health problem the medicinal plants are used, their usage art, area and the used parts have been determined too. The research results show that 12.58% of the species are used in intestinal problems and 8.60% for diuretic. Evaluating from this point of view the region includes very rich species could be used in different health problems. The results shows that average annual income of the medically used plant selling companies is about 33,333$. Increasingly demands for the medically used plants have been raised the medically used plant companies about 60% in the last decade. The relevance of Ethnopharmacologically used plants is increasing in Turkey and in the World. Important is to meet the demand without endanger the rich plant species resources.  相似文献   

8.
This paper presents the results of research conducted between 2009 and 2014 in the village of Khanda Sharol in the state of Rajasthan, India. Our research objective was to determine how the livelihoods of village residents have been affected by the intensification of forest use, and the resulting loss of domestic access to traditionally used forest resources. Results indicate that changes in forest cover have resulted in a loss of livelihood options for village residents. Yet rather than being victimized by environmental change processes, this paper shows how villagers have responded by partnering with public and private actors to develop a community protected forest area that is now helping villagers to meet their livelihood needs. These findings suggest that sustainable livelihoods in rural regions of India require committed and scaled approaches involving local, public, and private actors.  相似文献   

9.
The effects of thinning on mineral soil and forest floor for three different thinning intensities (control, moderate and heavy) were studied in a sessile oak forest 8 years after treatment. To examine responses to thinning, mass, organic matter and total nitrogen content in forest floor, bulk density and fine soil weight, total nitrogen, organic carbon concentrations and pH in upper mineral soil horizons were measured, and the results compared to control plot. The thinned plots have shown higher total nitrogen concentration and organic carbon in soil. Total mass, weight of layers of forest floor have shown significant patterns with thinning intensity. The present results indicate that various intensities of thinning for a sessile oak stand had major influence on soil and forest floor in eight years following treatment.  相似文献   

10.
Primary surveys were conducted in 20 villages and an equal number of community managed forests (CMFs) of two districts, Adilabad and Chittoor in the state of Andhra Pradesh in southern India. The interviews conducted with 216 respondents listed a total of 22 and 23 non-timber forest products (NTFP) from Adilabad and Chittoor districts, respectively, of which 15 species were common to both study districts. Eight of these NTFPs, including, Sterculia urens, Thysanolena maxima, Sapindus emerginatus, Dendrocalamus strictus, Pongamia pinnata, Schleichera oleosa, Azadirachta indica and Diospyros melenoxylon were collected for commercial purposes. The vegetation survey was conducted in a total of 240 sample plots in 20 CMFs, and found 15 NTFP species from Adilabad and 18 NTFP species from Chittoor. The density of NTFP trees in Adilabad was 52 trees/ha, as against an overall tree density of 278 trees/ha, while in Chittoor it was only 28 trees/ha as against an overall density of 110 trees/ha. The regeneration density of NTFP species was, however, higher in Chittoor. Some of the NTFP species, prioritized for conservation, included Sterculia urens, Tamarindus indica, Phyllanthus emblica, Strychnos nuxvomica, S. potatorum and Anogeissus latifolia.  相似文献   

11.
The fluoride concentration in ground water was determined in ten villages of Rohtak district of Haryana state (India). The fluoride concentration in the underground water of these villages varied from 0.034-2.09 mg/l. Various other water quality parameters, viz., pH, electrical conductivity, total dissolved salts, total hardness, total alkalinity sodium, potassium, calcium, magnesium, carbonate, bicarbonate, chloride and sulfate were also measured. A systematic calculation of correlation coefficients among different physicochemical parameters indicated considerable variations among the analyzed samples with respect to their chemical composition. Majority of the samples do not comply with Indian as well as WHO standards for most of the water quality parameters measured. Overall water quality was found unsatisfactory for drinking purposes. Fluoride content was higher than permissible limit in 50% samples.  相似文献   

12.
Surface soils affected by forest fires from Igbanko mangrove forest in Nigeria were analyzed for 16 EPA priority polycyclic aromatic hydrocarbons (PAHs) using gas chromatography–mass spectrometry (GC–MS). The total PAHs concentrations in the soils ranged from 63 to 188?µg?kg?1 dry weight (average: 108?µg?kg?1). The three predominant PAHs in the soils were naphthalene (Na), fluoranthene (Flu), and benzo(b)fluoranthene (BbF). Compared to the control sample (19?µg?kg?1), elevated PAHs concentrations were observed in the soils, an indication of some level of PAHs contamination. PAHs source diagnostic ratios of Flu/(Flu?+?Pyr) and Ant/(Ant?+?Phe) indicated that the PAHs have a pyrogenic origin which may have resulted from combustion of grass, wood, or coal. An assessment based on Canadian soil quality guidelines indicated that the studied locations do not pose any serious adverse risk on human health.  相似文献   

13.
In this study, growth potential of Crimean juniper (Juniperus excelsa Bieb.) seedlings for the first growing season under Tekir Forest Nursery conditions in Kahramanmaras was evaluated. The height growth of Crimean juniper seedlings was relatively close to that of Lebanon cedar (Cedrus libani A. Rich.) seedlings produced in the same nursery, but their root collar diameters were fairly lower than that of Lebanon cedar seedlings. According to coniferous seedling standards of Turkish Standards Institute, the height growth of Crimean juniper seedlings was fairly good, but their root collar diameters were slightly small. In this respect, that 2+0 or 1+1 Crimean juniper seedlings are used in reforestation activities in the region would be more useful than 1+0 seedlings.  相似文献   

14.
Guoliang Liu  Shijie Han 《Ecological modelling》2009,220(13-14):1719-1723
In their efforts to deal with global climate change, scientists and governments have given much attention to the carbon emissions associated with fossil fuels and to strategies for reducing their use. While it is very important to burn less fossil fuel and to employ alternative energy sources, other carbon-reduction options must also be considered. Given that forests comprise a large portion of the global landbase and that they play a very significant role in the global carbon cycle, it is logical to examine how forest management practices could effect reductions in carbon emissions. Many papers that discuss forest carbon sinks or sources refer only to the short term (<20 years). This paper focuses on the sustainable carbon storage contributions of a forest over the long term. This paper explains that long-term carbon storage and reduced carbon fluctuation can be achieved by a combination of improved forest management and efficient transfer of carbon into wood products. Here we show how three different forest management scenarios affect the overall carbon storage capacity of forest and wood products combined over the long term. We used a timber supply model and scenario analysis to predict forest carbon and other resource conditions over time in the Prince George Forest District, a 3.4-million-ha landbase in northern British Columbia. We found that the high-harvest scenario stores 3% more carbon than the low-harvest scenario and 27% (120 million tonnes) more carbon than the no-harvest scenario even though only 1.2-million ha is in timber harvesting landbase. Our results tell us that forest management practices that maintain and increase forest area, reduce natural disturbances in the forest, improve forest conditions, and ensure the appropriate and timely transfer of carbon into wood products lead to increasing overall carbon storage, thereby reducing carbon in the atmosphere.  相似文献   

15.
The West Anatolian Region is one of the most important areas for industrialization, population density and traffic in Turkey. Therefore, the leaves of Populus nigra L. (Salicaceae), which are used as biomonitor to investigate the levels of the trace elements Cd, Pb, Fe, Zn and Cu, were sampled at 30 locations having different pollution levels in the region. The concentrations of elements were determined by atomic absorption spectrometry. The samples were collected at both reference and contaminated locations where iron was found as the priority element. The strong association between a gradient of contamination and concentration in all samples tested indicates that they are reflecting well the environmental changes, and that they appear as appropriate biological indicators of heavy metal contamination.  相似文献   

16.
保持和提高森林土壤肥力质量是实现森林健康的基础。研究不同林型下土壤肥力质量对森林可持续经营具有重要意义。以东北过伐林区金仓林场中的落叶松Lartx gmelinii人工纯林、云杉Picea asperatax紫椴Tilia amurensis天然混交林、紫椴×白桦Betula platyphylla天然混交林、五角槭Acer monox白桦×落叶松天然混交林、五角槭×白桦×紫椴天然混交林、白桦×落叶松天然混交林和五角械×紫椴×青杨Populus pseudo-simonii天然混交林为研究对象,分析和比较了不同林分下的土壤物理和化学性质,并采用主成分分析与聚类分析相结合的方法评价了其土壤肥力质量。结果表明:①林分类型对土壤理化性质影响显著;随土壤深度增加,土壤密度和土壤pH值增大,而土壤含水量、物理性粘粒含量和养分质量分数减少,但其在不同林分下的变化程度不同;②土壤因子之间关系密切,物理性粘粒含量与含水量、全氮、速效钾质量分数呈极显著正相关,而与土壤密度和pH值呈显著负相关;土壤养分质量分数之间具有不同程度的显著正相关关系;③采用主成分分析法对不同林分下0~60cm的土壤肥力质量进行了评价,土壤肥力质量表现为天然混交林高于落叶松人工纯林;采伐降低了土壤的肥力质量;在落叶松人工纯林中,随着林龄的增加,土壤的肥力质量下降。通过对土壤肥力质量综合指标值的聚类分析,将研究区土壤肥力质量分为优、良、中、差4个等级,肥力质量属于中等以上(优、良、中等)的林地所占研究样地的比例为66.7%,研究区森林土壤肥力质量属于中等水平。建议在经营过伐林时,注意调整林分结构和树种组成,控制采伐强度,同时进行长期定位观测和比较,以改善林分整体的肥力状况。本研究结果为该地区林业可持续经营提供直接依据,也为东北地区森林土壤肥力质量评价提供参考。  相似文献   

17.
The objective of this study was to determine the dust concentrations in selected tractor and combine operations in eastern Mediterranean region in Turkey Mean dust concentrations were 137.9 mg m(-3), 83.6 mg m(-3), 80.3 mg m(-3), and 88.8 mg m(-3) respectively for soil packing, furrowing, straw making, and baling on tractors with no cabins whereas 106.9 mg m(-3) was found in combines without cabins, which are much higher than the limit dust concentration (10 mg m(-3)) considered hazardous for workers' health. In tractor operations with field-installed cabins, mean dust concentrations were 5.6 mg m(-3), 6.6 mg m(-3), 6.4 mg m(-3), and 3.7 mg m(-3), respectively in soil packing, furrowing, straw making, and baling while 4.7 mg m(-3) was measured in combines with field-installed cabins. Considering unit-manufactured cabins, mean dust concentrations were 1.1 mg m(-3), 1.6 mg m(-3), 3.2 mg m(-3), and 1.4 mg m(-3) respectively in tractor operations, and 1.4 mg mr(-3) in combine operations. Variance analyses showed that not only the respiration environment of the workers but also the field operation had a significant effect on measured dust concentrations (p < 0.01). Pearson correlation coefficient was 0.74 (very strong level) between dust concentration and wind speed in soil packing, 0.46 (medium level) between dust concentration and wind speed in baling, and 0.44 (medium level) between dust concentration and ground speed in combining.  相似文献   

18.
Taumetopoea pityocampa (Den. and Schiff) is one of the most common defoliator insects found in Turkey. Although several methods have been used in attempting to control this major forest pest up to now but the problem still remains largely unsolved in Turkey. There is an urgent need to control and minimize the damages caused by these defoliating caterpillars. Therefore, we planned and applied field treatments using by Foray 76B and VBC 60074 to put forward to the efficiency of these bioinsecticides against PPM. The bioinsecticides included in Bacillus thuringiensis subsp. kurstaki (Btk). The vulnerable performance of a single application has been observed in the field trial of these bioinsecticides with mortality rates ranging from 97 to 99% in Turkey's pine forests.  相似文献   

19.
Leaf-litter processing by invertebrates in a mangrove forest in Queensland   总被引:6,自引:0,他引:6  
The way leaf shredders handle and shred leaves under laboratory conditions and in the mangrove forest at Myora Springs, Queensland, Australia, was investigated during the period 1980 to 1984. Field observations on the behaviour of the crab Sesarma erythrodactyla during low tide revealed that this species spends most of its time foraging over mud. S. erythrodactyla eats mangrove leaves where they fall or drags them into burrows or hollow logs. Through their feeding activities, crabs (S. erythrodactyla, Metopograpsus frontalis, Helice leachii, Clistocoeloma merguiensis, Leptograpsus variegatus, Paragrapsus laevis, Ilyograpsus paludicula), isopods (Exospaeroma alata, Campaecopia sp.) amphipods (Orchestia sp., Melita sp.), and a capitellid polychaete (Capitellides sp.), break down whole mangrove leaves into small particles. The way in which a leaf is broken down by leaf-shredders influences the size and composition of the particulate organic matter (POM) in the environment. The POM egested by leaf-shredders varies from 32 to 1171 m. POM in this size range occurs in the guts of 38 invertebrate species which feed on mud, suggesting that they depend on the plant detritus produced by leafshredders as a source of food. Leaf-shredders therefore constitute a primary link in the marine food web of mangrove forests.  相似文献   

20.
The accumulation of some heavy metals such as Pb, Cd, Cu and Ni was determined in water sediment and fish samples (Albumus escherichii, Cyprinus carpio and Silurus glanis) collected from Nallihan Bird Paradise (NBP) and its vicinity (Sariyar Dam). The results showed that these metals are found widespread throughout the study area, but metal concentrations in the water samples are below the detection limits (BDL). Pb, Cd, Cu and Ni contamination were determined in sediments and in fish tissues (muscle and liver) and it was seen that they were accumulated and biologically magnified in lish tissues. Metal concentration levels in sediment samples were higher than that of water and fish tissues. The highest amount of metal concentrations in sediment samples among seven stations were determined in Usakbuku (Pb: 0.49 ppm), Sakarya River (Cu: 1.12 ppm) and Sariyar (Ni: 0.77 ppm). Unlikely to the other stations, no metal residues were determined in the sediment samples ofAladag Creek Station.  相似文献   

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