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1.
A community-based monitoring system that focuses on natural resource use and forest quality in montane evergreen forest and
miombo woodland areas was developed and implemented in 23 villages in 2002 as part of a participatory forest management regime
in Iringa District, Tanzania. The scheme was developed to suit the needs and capacities of locally-elected natural resource
committees managing and monitoring natural forests. Rather than measuring biodiversity, the monitoring is focused on resource
extraction and disturbance. High levels of commitment to the monitoring were displayed by village level managers, and the
preliminary feed-back indicates that the monitoring scheme provides them with the relevant information needed to suggest appropriate
management interventions. While external support has been essential to cover development costs, natural resource revenue generated
at village level can provide most of the running costs. Once developed, the scheme can, however, be transferred to similar
areas at significantly lower costs that can be met by Tanzanian District budgets. Natural resource revenue generated from
montane forests is generally much lower than in woodland areas due to restrictions on resource extraction imposed as a consequence
of national and international interests. Opportunities to provide economic incentives for montane forest managers through
direct utilisation of the resource are limited and it remains to be seen whether other non-economic incentives can sustain
long term commitment in these biodiversity rich areas. Findings indicate that the key elements of this local resource utilisation
monitoring scheme are simplicity, incentive mechanisms, transparency and accountability, and autonomy for local managers.
However, the methods may not provide sufficient data on changes in biodiversity values in the high value forests and may need
to be augmented by conventional monitoring by scientists funded by national or international institutions. Elements of the
scheme are now being institutionalised within the forestry sector in Tanzania. 相似文献
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Sean P. Healey Warren B. Cohen Thomas A. Spies Melinda Moeur Dirk Pflugmacher M. German Whitley Michael Lefsky 《Ecosystems》2008,11(7):1106-1119
Interest in preserving older forests at the landscape level has increased in many regions, including the Pacific Northwest
of the United States. The Northwest Forest Plan (NWFP) of 1994 initiated a significant reduction in the harvesting of older
forests on federal land. We used historical satellite imagery to assess the effect of this reduction in relation to: past
harvest rates, management of non-federal forests, and the growing role of fire. Harvest rates in non-federal large-diameter
forests (LDF) either decreased or remained stable at relatively high rates following the NWFP, meaning that harvest reductions
on federal forests, which cover half of the region, resulted in a significant regional drop in the loss of LDF to harvest.
However, increased losses of LDF to fire outweighed reductions in LDF harvest across large areas of the region. Elevated fire
levels in the western United States have been correlated to changing climatic conditions, and if recent fire patterns persist,
preservation of older forests in dry ecosystems will depend upon practical and coordinated fire management across the landscape.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Author Contributions: The study was conceived and designed by S.P.H., W.B.C., T.A.S, and M. M. The paper was written primarily
by S.P.H, with editorial help by T.A.S. and W.B.C. The research itself, including mapping and analysis, was performed by S.P.H.,
D.P., M.G.W., and M.L. M.M. contributed additional methodologies related to the creation and validations of maps of historical
older forests. 相似文献
4.
A. York 《Journal of Insect Conservation》1999,3(3):191-199
Low-intensity fire is extensively used in Australian dry eucalypt forests to reduce fuel levels. The long-term impact of this management practice on terrestrial invertebrates is, however, unknown and is of concern given their contribution to ecosystem function and forest biodiversity. This study found that areas subjected to frequent low-intensity fire had significantly lower numbers of spiders, ticks and mites, pseudoscorpions, woodlice, springtails, bugs, beetles, ants and insect larvae in the leaf litter compared with adjacent unburnt areas. Taxa numbers were between 41 and 82% lower and these reductions in abundance have led to an overall decline in taxon richness. This decrease was attributed to a reduction in the amount of litter and associated moisture levels, and a simplification of habitat structure. The extent of local and regional extinctions will depend upon the scale of this disturbance, with future studies investigating the impact on individual species within these communities. A comparison of two sampling techniques, pitfall-trapping and litter extraction, highlighted important considerations for spatial components of invertebrate sampling designs. 相似文献
5.
In coastal areas of Australia, there are extensive infestations of the environmental weed Chrysanthemoides monilifera ssp. rotundata (bitou bush). This study looked at the impact of long-term infestations on the abundance and assemblage composition of leaf
litter invertebrates. Assemblages were compared in weed infested and native shrublands along the New South Wales coastline
over 12 months. The total abundance was not significantly reduced in the weedy habitat but the abundance of mites, thrips,
spiders, ants, and centipedes was reduced at many sites. The invertebrate assemblages also differed between habitats, with
the C. monilifera supporting a lower diversity of beetles. However, the millipedes, amphipods, earthworms, pseudoscorpions and isopods appeared
to respond positively to the invasion, occurring in higher abundance and detected more frequently in the weedy areas. This
has been partially attributed to a change in microclimate within the C. monilifera infestations. It is generally moister and darker, which these invertebrates tend to prefer. Secondly, C. monilifera produces less leaf litter of higher quality, and possibly higher palatability than the native sclerophyllous vegetation,
which may encourage species that consume litter. 相似文献
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7.
M. G. Paoletti M. Bressan Professor C. A. Edwards 《Critical Reviews in Plant Sciences》1996,15(1):21-62
The aim of this paper is to try to face up to the increasing demand for soil bioindicators to determine the state of health of the environment. Terrestrial ecosystems are contaminated by a wide range of pollutants originating from different sources and having very different distributions. Animals, plants, and, more generally, ecological community patterns seem to be able to register qualitative and quantitative environmental changes due to anthropogenic activities. A clear and accurate definitive generalization of the response of invertebrate populations to direct and indirect environmental stresses is very difficult; many variables can interact, such as the particular invertebrate species and/or the developmental stage exposed to the stress, the particular environmental stress due to different pollutants, and the environmental physical factors as well, sometimes intervening in complex patterns. 相似文献
8.
Often a single indicator invertebrate taxon is used for assessing changing landscape patterns. However, we argue here against the exclusive selection of a single group. Covariation in diversity patterns of spiders, carabids, staphylinids and ants were compared in and between five highly naturally-fragmented Afromontane forest patches (size range: 3.5–25.2 ha) in South Africa. Significantly fewer individuals and species were captured in smaller forest patches (<6 ha) for most of the taxa, except Formicidae, where a higher number of species were captured in medium-sized patches (7–9 ha). When sampling effort was standardized, a higher diversity (rarefaction and Simpson's diversity index) was obtained in the smaller patches for Carabidae, Staphylinidae and Formicidae. The only significant positive correlation between taxa, in terms of numbers of species, was between Carabidae and Staphylinidae. The other taxa showed only weak positive correlations between species richness, or negative correlations. Multivariate techniques showed significant species turnover between patch assemblages for each taxon, and also showed that some taxa are more similar in assemblage-structure than others. An index of complementarity showed that species compositions of the selected taxa varied greatly between forest patches of different sizes. Our results support the multi-taxa approach, in conservation studies, even at the level of taxonomically-related groups sharing a common habitat stratum. 相似文献
9.
对云南乃古石林出现频度最高的5种藓类植物做了水土保持作用研究。5种藓类植物鳞叶藓(Taxiphyl-lum taxirameum(Mitt.)Fleisch.)、灰白青藓(Brachythecium albicans(Hedw.)B.S.G.)、小牛舌藓全缘亚种(Anomodon minor subsp.integerrimus(Mitt.)Iwats.)、中华细枝藓(Lindbergia sinensis(C.Muell.)Broth.)和拟扁枝藓(Homaliadelphus targionianus(Mitt.)Dix.et P.Varde)的生物量等测定结果显示:平均生物量为24.31~103.78 g/m2,平均饱和吸水率为818.24%~1462.02%,最高的达到1659.27%,最低的也达到了590.95%;平均饱和吸水量为216.92~791.80 g/m2,最高的达到1790.28 g/m2;平均成土率为47.32%~111.58%,最高的达到194.82%,最低的也达到19.33%;平均成土量为9.01~46.73 g/m2,最高的达到110.17 g/m2。小牛舌藓全缘亚种的平均饱和吸水量和平均生物量远远高于其他4种藓类,分别为:791.80 g/m2和103.78 g/m2。相关性分析表明,小牛舌藓全缘亚种的保水成土相关性最显著。它的干重与饱和吸水重、生物量与干重、生物量与饱和吸水量、生物量与成土量、饱和吸水量与成土量都是呈正极显著相关。研究结果表明,在乃古石林剑状喀斯特这种缺少土壤、干旱且保水能力弱的景区环境,藓类植物以其特有的生态功能在石林景观多样性、水土保持等方面具有十分重要的作用。 相似文献
10.
Pauline M. Ross 《Wetlands Ecology and Management》2006,14(2):167-184
Trampling paths are a feature of estuarine habitats in southeastern Australia. An experimental investigation quantified the
impact of trampling over a 3 year period on the microhabitat features and macrofaunal assemblages in a temperate mangrove
forest in New South Wales, Australia. The magnitude of the impact varied between 0 and 25 passes (representing a visit by
25 people), which reduced the biomass of the Bostrychia–Caloglossa algal association by 50%. The frequency of trampling varied between one and four, simulating a single and seasonal visits
by a group of people to the mangrove forest. The main impact of trampling was an alteration to the microhabitat structures
of the forest floor including a decrease in the number and vertical height of pneumatophores, an increase in the proportion
of bent and broken pneumatophores in trampled lanes and a decrease in the biomass of the epiphytic Bostrychia–Caloglossa algal association. The macrofauna most impacted by trampling were the gastropods most commonly associated with the pneumatophores
and algal assemblages and included Ophicardelus spp. and Assiminea buccinoides. Those gastropods least impacted by trampling were commonly associated with the surface of the sediment or were known to
move over the surface and included Bembicium auratum and Cassidula zonata. There was little impact on the main burrowing crab, Heloecius cordiformis. There were some indirect impacts of trampling with the recruitment of Ophicardelus spp. Assiminea buccinoides and Salinator solida reduced in the subsequent year after trampling had ceased. People can create walking paths in mangrove forests that have
long term effects on the habitat. An appropriate management emphasis may lie in maintaining the structural features of the
habitat. 相似文献
11.
森林植被的自然火干扰 总被引:18,自引:1,他引:18
森林植被的自然火干扰邱扬(山西大学黄土高原研究所,太原030006)NaturalFireDisturbanceofForestVegetation.QiuYang(InstituteofLoesPlateau,ShanxiUniversity,... 相似文献
12.
P. T. Manders 《植被学杂志》1990,1(4):483-490
Abstract. Forests in the southwestern Cape are restricted to sheltered stream banks and patches of rock scree owing to protection from recurrent fire and the more favourable soil moisture conditions in these habitats. The effects of a prescribed burn on 17 March 1987 on the forest / fynbos boundaries in the Swartboskloof catchment are described. No evidence of erosion of the forest edge was recorded, although this could be ascribed to the low intensity of the fire. Soil properties, primarily pH and aluminium and available phosphorus levels, differed markedly between forest and fynbos. It is argued, however, that this is a result, not a cause of vegetation change. Light extinction levels and soil moisture availability after the fire were lower in the fynbos than in the forest, and are considered to preclude incursions of forest species into fynbos of a low post-fire age. 相似文献
13.
Quantitative Evidence for Increasing Forest Fire Severity in the Sierra Nevada and Southern Cascade Mountains, California and Nevada, USA 总被引:2,自引:0,他引:2
Recent research has concluded that forest wildfires in the western United States are becoming larger and more frequent. A
more significant question may be whether the ecosystem impacts of wildfire are also increasing. We show that a large area
(approximately 120000 km2) of California and western Nevada experienced a notable increase in the extent of forest stand-replacing (“high severity”)
fire between 1984 and 2006. High severity forest fire is closely linked to forest fragmentation, wildlife habitat availability,
erosion rates and sedimentation, post-fire seedling recruitment, carbon sequestration, and various other ecosystem properties
and processes. Mean and maximum fire size, and the area burned annually have also all risen substantially since the beginning
of the 1980s, and are now at or above values from the decades preceding the 1940s, when fire suppression became national policy.
These trends are occurring in concert with a regional rise in temperature and a long-term increase in annual precipitation.
A close examination of the climate–fire relationship and other evidence suggests that forest fuels are no longer limiting
fire occurrence and behavior across much of the study region. We conclude that current trends in forest fire severity necessitate
a re-examination of the implications of all-out fire suppression and its ecological impacts.
Author Contributions: Jay Miller designed the study, performed research, analyzed data, and wrote the article. Hugh Safford performed research,
analyzed data, and wrote the article. Michael Crimmins performed research and analyzed data. Andi Thode designed the study
and performed research. 相似文献
14.
Twelve nations involved in boreal or temperate forest management are committed to reporting on indicators under the Montreal Process as a mechanism for assessing progress towards sustainable forest management. For fauna, invertebrates are often considered too poorly known and diverse to include in sustainability indicator reporting. The alternative view, that no monitoring of sustainability can be considered adequate without inclusion of some invertebrate species, is espoused in this paper. The microhabitats of soil and litter, foliage and canopy, bark and branch, dead standing trees and coarse woody debris are highlighted as relevant in the context of determining the impacts of forest management on invertebrates and for selecting representative species. It is argued that a selection of those species from each of the key microhabitats that are restricted to later stages of succession should be monitored. This could be complemented by a selection of easily monitored species from a range of functional groups as a means of endeavouring to pick up adverse impacts not foreseen on the basis of present knowledge. In the longer term, habitat indices (developed from predictive models of fauna habitat) should be used to monitor the occurrence of indicator species across the broader landscape, rather than at specific sites where monitoring of species takes place. Most countries would be in a position to select indicator species and commence monitoring for some key microhabitats (e.g. soil and litter). However, further research is needed in many countries before indicator species can be selected for other key microhabitats (e.g. coarse woody debris). 相似文献
15.
16.
N. M. Korovchinsky 《Hydrobiologia》1986,141(1-2):83-88
This paper briefly reviews systematic, production and biocenotic studies on invertebrates of the littoral zone of Lake Glubokoe. It presents new data for a number of years on the spatial distribution and population dynamics of species (mainly cladocerans) constituting a zoocenosis confined to the lower surface of floating leaves of Nuphar luteum. 相似文献
17.
Kjell Danell 《International Review of Hydrobiology》1981,66(6):837-845
During two winters, the benthic invertebrates in a shallow northern Swedish lake (66 °N) were studied. The lake is ice-covered for about 200 days a year. Live Lamellibranchiata, Oligochaeta. Hydracarina, Isopoda, Heteroptera, Cole optera and Diptera were found in samples of ice and of frozen lake-bottom sediments. During the winter in which the bottom froze deepest, a 70–90% decrease in numbers of live Chironomidae larvae was recorded between the autumn and following early spring. 相似文献
18.
海洋无脊椎动物抗菌肽研究进展及其在食品保鲜中的应用 总被引:1,自引:0,他引:1
海洋无脊椎动物抗菌肽抑菌广谱,稳定性高,且对生物体本身无害,其应用日益引起大量研究者的关注。综述了抗菌肽的几种类型、抑菌机理,介绍了海洋无脊椎动物抗菌肽研究进展、存在的问题并分析其在食品保鲜中的应用前景。 相似文献
19.
Effects of high suspended-sediment (SS) levels (up to c. 20,000 NTU) from fine clay on 5 species of New Zealand stream insects and the crayfish Paranephrops planifrons were assessed by short-term (24 h) exposures to different SS concentrations. There were no patterns of increasing mortality over 24 h with increasing SS concentrations. Effects of longer-term exposure (14 days) of repeated 4 h exposures to lower SS concentrations (c. 1000 NTU) on the common leptophlebiid mayfly Deleatidium were also investigated. No difference in mortality was found between the test and control solutions. We suggest that so-called ‚sensitive’ invertebrates are tolerant of high SS concentrations, and that even repeated exposures to high SS concentrations have little effect on survival. Absence of these animals from catchments with high SS concentrations thus most likely reflects adverse changes to instream habitat conditions, such as filling of interstitial spaces, contamination of food sources, or both. 相似文献
20.
There are two sewage outfalls along the Jordanian coastline in the Gulf of Aqaba. During 1982 and 1983 a total of 328 core samples (0.01 m2 to a depth of 15 cm) were collected from the two outfalls, two control stations which resemble the outfalls in depth and sediment texture, and from two stations 100 m on both sides of each outfall. Faunal analysis revealed that the total number of individuals, number of species, species richness, and faunal similarities of macrobenthic invertebrates were lower at the sewage outfall near the phosphate loading port than the control station during both collections. At the 100 m stations, the numbers of individuals were generally higher than the sewage and control stations. The number of species, however, was highest at the control station and lowest at the sewage outfall. At the other sewage outfall, where the sewage effluent is discharged sporadically, no measurable effects on macrobenthic invertebrates were found. 相似文献