首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
A study was undertaken around Mt Cameroon to examine the role of biological and cultural diversity in the livelihood strategies of indigenous villagers and migrants to the region. Surveys of resources consumed and sold by 118 households were undertaken in five villages over the course of 1 year, the perspectives and practices of cocoa farmers documented, and useful tree species retained or planted on six cocoa farms mapped. Cocoa farms in this region generate more significant benefits for biodiversity conservation and local livelihoods than commercial plantations, but also place pressure on forest reserves and require chemical inputs. Roughly 50 tree species are commonly retained or planted on cocoa farms, primarily for timber or food, with many of these having high conservation value. Average tree density of non-cocoa trees was 15 trees per hectare, with tree densities higher, and a larger percentage of species used, on indigenous Bomboko farms than migrant farms. Both migrant and indigenous households rely on forest as a complement to farm income, but indigenous households do this to a far greater extent, while also making extensive use of fallow and home gardens. Indigenous households also derive roughly four times the income from wild and native species compared to migrants. While diversified cocoa farms contribute to conservation and livelihoods in the region, indigenous livelihoods grow from and require the conservation of a broader range of species and habitats, including natural forest.  相似文献   

2.
Arabuko Sokoke Forest is the largest remaining single block of indigenous dry coastal tropical forest in Eastern Africa. Households within a 5 km buffer zone depend heavily on the forest for their livelihood needs, and the pressure on forest resources is on the increase. In May 2015, 109 households were interviewed on resources they obtain from the forest, in terms of the self‐reported level of monthly income. We found household income and farm size significantly positively correlated with benefits from the forest, highlighting the possible influence of household wealth in exploiting forest resources. A large proportion of households (32%) had limited knowledge of local birds, while human–bird conflict was reported by 44% of the households. While many households were keen to participate in conservation projects that maintain the forest, 44% had no knowledge of the forest management plan, and 60% of those interviewed had no idea of how forest zones were designated for particular activities. Drivers for local community participation in conservation projects appear to be sustainable income and fulfilment of basic household needs.  相似文献   

3.
Forest-product use among nonforest dwelling cultural groups in Southeast Asia is not well known, particularly in contrast to what is known about indigenous forest-product collectors. A case study in one lowland Filipino village in Leyte, Philippines, revealed that over half of village households depend upon 8 species of commercially valuable rattan and 8 species of timber as a primary source of livelihood, and that all village households collected forest-products for supplementary and emergency income. The future of the rattan and timber trade on Leyte is seriously threatened by agricultural encroachment and intensive collecting pressures in the absence of forest management.  相似文献   

4.
This study evaluated whether processing non-timber forest products (NTFPs) and establishing trade partnerships between forest communities and companies enhance the outcomes of NTFP commercialization. In particular, we evaluated whether product processing, partnerships, or their combination was associated with a number of outcomes related to the well-being of forest inhabitants and forest conservation. We based our analyses on ethnographic and quantitative data (i.e., survey and systematic observations) gathered at seven communities from five societies of the Brazilian and Bolivian Amazon. Our results indicated that product processing and partnerships do not represent a silver bullet able to improve the results of NTFP commercialization in terms of well-being and conservation indicators. Compared with cases without interventions, households adopting partnerships but not product processing were most often associated with improved economic proxies of well-being (total income, NTFP income, food consumption and gender equality in income). In comparison, the combination of product processing and partnerships was associated with similar outcomes. Unexpectedly, product processing alone was associated with negative outcomes in the economic indicators of well-being. All of the investigated strategies were associated with less time spent in social and cultural activities. With respect to forest conservation, the strategies that included a partnership with or without processing produced similar results: while household deforestation tended to decrease, the hunting impact increased. Processing alone was also associated with higher levels of hunting, though it did not reduce deforestation. Our results indicate that establishing partnerships may enhance the outcomes of NTFP trade in terms of the financial outcomes of local communities, but practitioners need to use caution when adopting the processing strategy and they need to evaluate potential negative results for indicators of social and cultural activities. With respect to conservation, the three strategies are promising for reducing deforestation, but more pervasive impacts, such as hunting, might increase.  相似文献   

5.
Levels of transaction costs in community‐based forest management (CBFM) in four communities adjacent to the Ambangulu mountain forests of the north‐east of Tanzania were assessed through questionnaire responses from 120 households. Costs and benefits of CBFM to the rich, medium and poor groups of forest users were estimated. Costs of CBFM were participation in forest monitoring and time spent in meetings. Benefits included forest products consumed at household level. Transaction costs relative to benefits for CBFM were found to be higher for poorer households compared with medium income and richer households. Higher income groups obtained the most net benefits followed by medium and poorer households. Community involvement in forest management may lower the transaction costs incurred by government, but a large proportion of these costs are borne by poorer members of the community. Transaction costs are critical factors in the success or failure of CBFM and need to be incorporated into policies and legislation related to community‐based natural resource management.  相似文献   

6.
Local communities in central Brazil harvest buriti palm (Mauritia flexuosa) fruit from swamp forests as well as using them for agriculture and cattle and pig farming. This study describes the intensity of forest use by buriti fruit harvesters and identifies how their socioeconomic conditions influence resource use. We visited 75 swamp forests where buriti fruits are harvested and interviewed the head of the nearest household. Agriculture was practiced in 72?% of forests and cattle farming in 52?%. For almost half (48?%) of households agriculture and buriti fruit harvest were the main sources income. Forests resources were equally important to all socioeconomic classes, even richer farmers. The intensity of fruit harvest did not differ between collective and private use regimes of forests. Market access was a limitation to fruit harvest intensity. The high intensity of swamp forest use suggests that their conservation will require change to current management practices.  相似文献   

7.
Aim The New Zealand terrestrial mollusc fauna is among the most speciose in the world, with often remarkably high richness at lowland forest sites. We sought to elucidate general explanations for patterns of richness in terrestrial mollusc communities by analysis of species coexistence and habitat relationships within a New Zealand district fauna. Location Pukeamaru Ecological District, eastern North Island, New Zealand. Methods We sampled molluscs using qualitative methods at twenty-three sites and quantitatively by frame sampling of scrubland-forest floor litter at sixteen of these sites and analysed patterns of species richness and turnover in relation to regional species pools and local habitat attributes. We then tested for nonrandom assemblage of taxa along diversity and habitat gradients. Results Ninety-four indigenous mollusc species were recorded from a district fauna estimated at 102 indigenous species: only two species were endemic. From the presumptive geological history of the district, the low endemism, and Brooks parsimony and indicator species analyses of faunal relationships, the communities were indicated to have resulted by accumulation of colonists from other New Zealand districts since the Miocene. Richness ranged from two or three indigenous species in dune habitats to fifty-nine species in a floristically rich forest. Beta diversity was high and site occupancy per species was low, indicating communities structured by successive replacement of ecological equivalents. Sites differing in vegetation had characteristic species assemblages, indicating a degree of habitat specialization. Canonical correspondence analysis indicated that canopy tree species, canopy height, floristic diversity, altitude, litter mass, and litter pH were important determinants of species assemblage in scrubland and forest. Richness was strongly associated with site floristic diversity and, for litter-dwelling species, the pH of litter substrate. High richness occurred at those sites supporting molluscs in high abundance. Shell-shape distributions were essentially Cainian unimodal, with communities dominated by snail species with subglobose to discoidal shells. Mean and variance of shell size increased with mollusc species richness and floristic diversity at sites, indicating dominance of communities by small-shelled species at early successional or floristically poor sites, and increased richness resulting from addition of larger snails into vacant niches. Shifts in shell form were associated with sympatry in several congeneric taxa. Main conclusions The underdispersion of shell shape, relative to faunas elsewhere in the world, indicates that community structure in New Zealand land snail faunas has been constrained by limited phylogenetic diversity and/or by convergence upon successful adaptations. The remarkably high richness that characterizes these communities indicates special conditions allow coexistence of numerous species. The relationship between floristic diversity at sites and the richness, diversity, and shell-size distributions of the molluscs suggests assemblages structured around niche partitioning among competing species. While there is an element of congruence between vegetation and mollusc pattern, this study indicates that assembly rules will be defined, and spatial pattern predicted, only through a better understanding of the linkage between regional species pool, organism traits, environment, and local community assemblage.  相似文献   

8.
Summary   Tawa ( Beilschmiedia tawa )-dominated forest fragments on farms within the Rotorua Basin were surveyed to quantify the likely recovery processes following exclusion of domestic livestock grazing, using a space-for-time substitution approach. Vegetation structure, plant diversity and soil fertility were measured at 24 sites within 15 forest fragments on six farms, covering a range in time since exclusion from grazing of 1–53 years. The forest fragments were compared with a large area of ungrazed forest in the nearby Lake Okataina Scenic Reserve. As time since exclusion from grazing increased, indigenous plant species diversity increased (up to 30–35 years); ground fern and epiphyte abundance increased (up to 30–35 years); tree seedling and sapling numbers, and litter cover also increased (up to 10–15 years); and overall tree numbers increased, while average tree diameter at breast height and overall tree basal area did not differ significantly. The soil fertility status was highly variable, obscuring clear patterns, although Olsen P status decreased with time since grazing exclusion. Once grazing of forest fragments ceases, significant changes in their diversity, structure and soil characteristics can be expected, which indicate recovery of these plant communities towards the conditions observed in ungrazed forest.  相似文献   

9.
1. Spatiotemporal patterns of canopy true bug diversity in forests of different tree species diversity have not yet been disentangled, although plant diversity has been shown to strongly impact the diversity and distribution of many insect communities. 2. Here we compare species richness of canopy true bugs across a tree diversity gradient ranging from simple beech to mixed forest stands. We analyse changes in community composition by additive partitioning of species diversity, for communities on various tree species, as well as for communities dwelling on beech alone. 3. Total species richness (γ‐diversity) and α‐diversity, and abundance of true bugs increased across the tree diversity gradient, while diversity changes were mediated by increased true bug abundance in the highly diverse forest stands. The same pattern was found for γ‐diversity in most functional guilds (e.g. forest specialists, herbivores, predators). Temporal and even more, spatial turnover (β‐diversity) among trees was closely related to tree diversity and accounted for ~90% of total γ‐diversity. 4. Results for beech alone were similar, but species turnover could not be related to the tree diversity gradient, and monthly turnover was higher compared to turnover among trees. 5. Our findings support the hypothesis that with increasing tree diversity and thereby increasing habitat heterogeneity, enhanced resource availability supports a greater number of individuals and species of true bugs. Tree species identity and the dissimilarity of true bug communities from tree to tree determine community patterns. 6. In conclusion, understanding diversity and distribution of insect communities in deciduous forests needs a perspective on patterns of spatiotemporal turnover. Heterogeneity among sites, tree species, as well as tree individuals contributed greatly to overall bug diversity.  相似文献   

10.
Sacred forest groves in Ghana are centuries old protected areas that were once part of continuous forest cover but now mostly exist as relict forest patches embedded in an agropastoral landscape. We conducted a year-long survey of the fruit-feeding butterfly fauna of four sacred groves and two forest reserves in the moist semi-deciduous forest zone of Ghana to characterize resident species diversity and complementarity among communities. Joint analysis of frugivorous butterfly diversity at these six forest fragments, which ranged in size from 6 to 5000 ha, was used to evaluate the conservation potential of these ancient indigenous reserves. A total of 6836 individuals were trapped across all sites, representing 79 species and five subfamilies. Community diversity was characterized in terms of, (a) number of species accumulated versus sampling effort, (b) rarefied species richness, (c) nonparametric richness estimates, (d) species evenness, (e) Simpson’s Index of Diversity, and (f) complementarity of communities. Diversity of the fruit-feeding butterfly communities, quantified in terms of both species evenness and rarefied species richness, was higher at the larger forest reserves than at the small sacred forest groves. Additionally, although all sites had species trapped only at that site, the 5000-ha forest reserve harbored a resident community that was clearly distinctive from and more diverse than the other communities including the other forest reserve. Hence, our findings add to the burgeoning body of data that indicates large reserves are the foundation of successful conservation programs. Nonetheless, we found these small forest patches contribute to biodiversity conservation in at least three ways and these are identified and discussed. We also identify a number of species that appear more or less vulnerable to dynamics of forest fragmentation based on changes in their relative abundance across sites and we interpret these data in the context of potential indicator species and theoretical predictions of at-risk species.  相似文献   

11.
Areas allocated for industrial logging and community‐owned forests account for over 50% of all remaining tropical forests. Landscape‐scale conservation strategies that include these forests are expected to have substantial benefits for biodiversity, especially for large mammals and birds that require extensive habitat but that are susceptible to extirpation due to synergies between logging and hunting. In addition, their responses to logging alone are poorly understood due to their cryptic behavior and low densities. In this study, we assessed the effects of logging and hunting on detection and occupancy rates of large vertebrates in a multiple‐use forest on the Guiana Shield. Our study site was certified as being responsibly managed for timber production and indigenous communities are legally guaranteed use‐rights to the forest. We coupled camera‐trap data for wildlife detection with a spatially explicit dataset on indigenous hunting. A multi‐species occupancy model found a weak positive effect of logging on occupancy and detection rates, while hunting had a weak negative effect. Model predictions of species richness were also higher in logged forest sites compared to unlogged forest sites. Density estimates for jaguars and ocelots in our multiple‐use area were similar to estimates reported for fully protected areas. Involvement of local communities in forest management, control of forest access, and nesting production forests in a landscape that includes protected areas seemed important for these positive biodiversity outcomes. The maintenance of vertebrate species bodes well for both biodiversity and the humans that depend on multiple‐use forests.  相似文献   

12.
The Knuckles range of forests has been identified as a unique biological resource in Sri Lanka with much biodiversity. It is also important as a watershed which feeds the Mahaweli reservoir system. Having considered the present hazardous land-use practices such as cardamum production and shifting cultivation, the Knuckles range has been declared a national wilderness area. The Forest Department is in the process of preparing the management plan for the area. There are about 48 villages in the vicinity of the forest. This study attempts to estimate the composition of income in the peripheral communities, ticularly the extraction of non-timber forest products (NTFP) from this range of forests. Data were collected using structured questionnaires from 60 households in three villages in the vicinity of the forest. The rural economy is described using a farming systems approach and the net income contributed by each activity in the farming system was estimated. Results show that nine components of the farming system use resources from the village and the forest, with at least 47 plant species used by the villagers for different purposes. Cardamum production and shifting cultivation contribute significantly to the total income of the household, but the majority of households in the study depend upon forest resources to supply some portion of their income. Nevertheless, the monetary value of the annual income generated by NTFP is much lower than income from either cardamum production or shifting cultivation. If cardamum production and shifting cultivation are to be restricted under the conservation program, there could be additional pressure put on NTFP. Therefore, we suggest a study of the natural regen-eration capacity of selected NTFP; such information should be used in finalizing the management plan in the Knuckles range of forests.  相似文献   

13.
Before Bwindi Impenetrable forest, Uganda, became a national park in 1991, there was a high level of human activity in much of the forest, especially cutting of large trees for timber by pitsawyers. This created extensive gaps in this tropical Afromontane rain forest. We quantified and compared tree regeneration in three sites that were logged at different intensities. Gap sizes in Bwindi, even under fairly natural conditions are very large (mean =4460.1 m2). Logging further enlarged the gap sizes and had a negative impact on tree regeneration. The study shows the strong role of logging disturbance in promoting an alternative successional pathway, where the large gaps created by logging are in a low‐canopy state dominated by a dense tangle of herbs, shrubs, and herbaceous or semi‐woody climbers. We recommend periodic monitoring of gap size and tree regeneration in the gaps to ascertain the trend of recovery from past logging disturbance.  相似文献   

14.
天山云杉种群空间格局与动态   总被引:22,自引:4,他引:18  
李明辉  何风华  刘云  潘存德 《生态学报》2005,25(5):1000-1006
天山云杉(Picea schrenkiana)林是天山林区的重要针叶林。研究调查了两块分别代表天山云杉不同演替阶段的标准地,应用Ripley’s K系数法研究了天山云杉种群空间格局与动态。结果表明:天山云杉是聚集型种群,天山云杉活立木、枯死木、天山桦(Betula tianschanica Rupr.)和天山柳(Salix tianschanica Rgl.)的空间格局均为聚集型;天山云杉枯死木的聚集强度大于天山云杉活立木的聚集强度;天山桦和天山柳的聚集强度大于天山云杉枯死木的聚集强度;天山桦和天山柳的空间格局随种群所处的演替阶段不同而不同,增长型种群在所有尺度上其空间格局都为聚集型,在大于70m尺度上表现为均匀格局,而天山云杉成熟林中的天山桦和天山柳只在小尺度(0~40m)上表现为聚集。随着天山云杉的生长,其聚集强度逐渐减小,聚集半径不断增大。从50a以下天山云杉到50~100a的天山云杉其聚集强度急速减小,这有利于天山云杉幼树获得足够的资源,是天山云杉幼树的一种生存策略或适应机制。150a以上天山云杉的聚集强度增加,这是由于天山云杉生长到150a左右时开始出现成熟后死亡,形成林窗有利于天山云杉林的更新。研究还对Ripley’s K系数法和频次检验法进行了比较,Ripley’s K系数法能够分析各种尺度下的种群空间格局,且不受样方大小的影响,结果清楚、直观。  相似文献   

15.
Sri Lanka has a long tradition of forest product use. The relationship of people with a dry zone forest was studied using a sample of 48 households in two villages that varied in distance to the forest and access to the market. All households interviewed collected subsistence forest products and a majority of them also collected commercial products. The daily peak-season income from commercial gathering was 4.5 to 7.7 times the daily labor wage. There is a strong gender specialization, with commercial gathering dominated by men whereas subsistence gathering is almost exclusively the task of women. The average forest-derived household income in the village closer to the forest and with better market access was nearly double that of the other village. Family size as a proxy of labor availability was the main discriminating factor between those households who did and those who did not gather commercial products. A small inverse relationship between forest gathering and size of household agricultural land (particularly paddy rice) was observed. No clear relationship was found between total household income and forest derived income, contradicting the view that commercial forest gathering is an exclusive activity of the poorest households.  相似文献   

16.
Phylobetadiversity is defined as the phylogenetic resemblance between communities or biomes. Analyzing phylobetadiversity patterns among different vegetation physiognomies within a single biome is crucial to understand the historical affinities between them. Based on the widely accepted idea that different forest physiognomies within the Southern Brazilian Atlantic Forest constitute different facies of a single biome, we hypothesize that more recent phylogenetic nodes should drive phylobetadiversity gradients between the different forest types within the Atlantic Forest, as the phylogenetic divergence among those forest types is biogeographically recent. We compiled information from 206 checklists describing the occurrence of shrub/tree species across three different forest physiognomies within the Southern Brazilian Atlantic Forest (Dense, Mixed and Seasonal forests). We analyzed intra-site phylogenetic structure (phylogenetic diversity, net relatedness index and nearest taxon index) and phylobetadiversity between plots located at different forest types, using five different methods differing in sensitivity to either basal or terminal nodes (phylogenetic fuzzy weighting, COMDIST, COMDISTNT, UniFrac and Rao’s H). Mixed forests showed higher phylogenetic diversity and overdispersion than the other forest types. Furthermore, all forest types differed from each other in relation phylobetadiversity patterns, particularly when phylobetadiversity methods more sensitive to terminal nodes were employed. Mixed forests tended to show higher phylogenetic differentiation to Dense and Seasonal forests than these latter from each other. The higher phylogenetic diversity and phylobetadiversity levels found in Mixed forests when compared to the others likely result from the biogeographical origin of several taxa occurring in these forests. On one hand, Mixed forests shelter several temperate taxa, like the conifers Araucaria and Podocarpus. On the other hand, tropical groups, like Myrtaceae, are also very representative of this forest type. We point out to the need of more attention to Mixed forests as a conservation target within the Brazilian Atlantic Forest given their high phylogenetic uniqueness.  相似文献   

17.
Frugivores and pollinators are two functional groups of animals that help ensure gene flow of plants among sites in landscapes under restoration and to accelerate restoration processes. Resource availability is postulated to be a key factor to structure animal communities using restoration sites, but it remains poorly studied. We expected that diverse forests with many plant growth forms that have less‐seasonal phenological patterns will provide more resources for animals than forests with fewer plant growth forms and strongly seasonal phenological patterns. We studied forests where original plantings included high tree species diversity. We studied resource provision (richness and abundance of flowers and fruits) of all plant growth forms, in three restoration sites of different ages compared to a reference forest, investigating whether plant phenology changes with restoration process. We recorded phenological data for reproductive plant individuals (351 species) with monthly sampling over 2 years, and found that flower and fruit production have been recovered after one decade of restoration, indicating resource provision for fauna. Our data suggest that a wide range of plant growth forms provides resource complementarities to those of planted tree species. Different flower phenologies between trees and non‐trees seem to be more evident in a forest with high non‐tree species diversity. We recommend examples of ideal species for planting, both at the time of initial planting and post‐planting during enrichment. These management actions can minimize shortage and periods of resource scarcity for frugivorous and nectarivorous fauna, increasing probability of restoring ecological processes and sustainability in restoration sites.  相似文献   

18.
Insect herbivores were collected from five species of dipterocarp tree seedling within a large‐scale reciprocal transplant experiment in Sabah, Malaysia, on alluvial and sandstone soils in both gap and understory plots. The aim was to determine whether the location and ecological specialization of seedlings influenced the herbivore communities found on and around them. Three major groups of folivores were collected: Coleoptera, Orthoptera, and larval Lepidoptera. Herbivory of all species was confirmed through laboratory trials. Herbivore abundance in the understory plots was extremely low relative to the gaps. Rank‐abundance curves were similar on both soil types, differing only within the Lepidoptera. Coleoptera and Orthoptera communities were numerically dominated by a small suite of species capable of feeding on all dipterocarp species tested, whereas lepidopteran communities had both greater species richness and diversity. When corrected for leaf area surveyed, the abundance of Coleoptera was similar on both soil types, while larval Lepidoptera were more abundant in sandstone plots and Orthoptera were more abundant in alluvial plots. Estimated species richness of all three taxa was greater in alluvial forest, but there were contrasting patterns in Simpson diversity and evenness between groups. Species richness of Lepidoptera was greatest on seedlings when grown in their native soil type, providing partial evidence for possible escape effects, although this was not matched by differences in folivore abundance. The link between herbivore communities and herbivory rates on rain forest tree seedlings is complex and is unlikely to be detected through simplistic measures of abundance, species richness, or diversity.  相似文献   

19.
Despite its central importance to tropical forest conservation, the understanding of patterns in traditional resource use still is incipient. To address this deficiency, we compared known palm uses among two indigenous (Yawanawd and Kaxinawá) and two folk (rubber tapper and ribeirinho) communities in Southwestern Amazonia (Acre, Brazil). We conducted one-hundred-and -forty semi-structured “checklist” interviews about palm uses with male and female adults in the four communities. The knowledge of each community about the uses of the 17 palm species common to all communities was compared by testing for significant differences in the mean number of uses cited per informant and by calculating the Jaccard similarity index of known uses of palm species among the four communities. The following three hypotheses were confirmed: 1) the use of palms differs according to the cultural preferences of each community; 2) indigenous communities know significantly more about palm uses than folk communities; and 3) part of the indigenous knowledge was acquired through contact with Amazonian folk communities.  相似文献   

20.
Plant resources are used, managed and conserved by local communities in many parts of the world. However, very few studies have examined the site-specific factors and mechanisms that affect resource extraction. We apply methodology from the social and biological sciences to examine the cultural and socio-economic factors that influence the harvest practice and resource use of indigenous wood carvers in the Maningrida region of central Arnhem Land. Woodcarvers from this region use a small number of carving timbers with two species dominant, Bombax ceiba and Brachychiton diversifolius. There were many cultural differences in harvest practice, with artists from the Kuninjku/Kunibeidji language community harvesting a greater number of tree species, larger quantities per harvest trip and smaller sized stems. Socio-economic factors also played an important role in facilitating the collection of stems as artists owning a vehicle acquired more stems than those who did not. Harvest sites closest to the township of Maningrida had higher visitation frequencies than those further away. These influences on harvest practice have significant implications for the ecological sustainability of timber harvesting in this region and we highlight the need to examine such localised factors when assessing the sustainability of indigenous wildlife harvests.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号