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1.
Quantifying local people's perceptions to climate change, and their assessments of which changes matter, is fundamental to addressing the dual challenge of land conservation and poverty alleviation in densely populated tropical regions To develop appropriate policies and responses, it will be important not only to anticipate the nature of expected changes, but also how they are perceived, interpreted and adapted to by local residents. The Albertine Rift region in East Africa is one of the world's most threatened biodiversity hotspots due to dense smallholder agriculture, high levels of land and resource pressures, and habitat loss and conversion. Results of three separate household surveys conducted in the vicinity of Kibale National Park during the late 2000s indicate that farmers are concerned with variable precipitation. Many survey respondents reported that conditions are drier and rainfall timing is becoming less predictable. Analysis of daily rainfall data for the climate normal period 1981 to 2010 indicates that total rainfall both within and across seasons has not changed significantly, although the timing and transitions of seasons has been highly variable. Results of rainfall data analysis also indicate significant changes in the intra-seasonal rainfall distribution, including longer dry periods within rainy seasons, which may contribute to the perceived decrease in rainfall and can compromise food security. Our results highlight the need for fine-scale climate information to assist agro-ecological communities in developing effective adaptive management. 相似文献
2.
Question: What is the relative importance of environmental and spatial factors for species compositional and phylogenetic turnover? Location: High‐rainfall zone of the Southwest Australian Floristic Region (SWAFR). Methods: Correlates of species compositional turnover were assessed using quadrat‐based floristic data, and establishing relationships with environmental and spatial factors using canonical correspondence analyses and Mantel tests. Between‐quadrat phylogenetic distance measures were computed and examined for correlations with environmental and spatial attributes. Processes structuring pa2t2terns of beta diversity were also evaluated within four broad floristic assemblages defined a priori. Results: Floristic diversity was strongly related to environmental attributes. A low significance of spatial variables on assemblage patterns suggested no evident effect of dispersal limitations. Species compositional turnover was especially high within the swamp and outcrop assemblage. Phylogenetic turnover was closely coupled to species compositional turnover, implying the occurrence of many locally endemic and phylogenetically relict taxa. Beta diversity patterns within assemblages were also significantly correlated with the local environment, and relevant correlates differed between floristic assemblage types. Conclusion: Phylogenetic diversity in the SWAFR high‐rainfall zone is clustered within edaphic microhabitats in a generally subdued landscape. A clustered rather than dispersed distribution of phylogenetic diversity increases the probability of significant plant diversity loss during periods of climate change. Climate change susceptibility of the region's flora is accordingly estimated to be high. We highlight the conservation significance of swamp and outcrops that are characterized by distinct hydrological properties and may provide refugial habitat for plant diversity during periods of moderate climate change. 相似文献
3.
John P. Simaika Michael J. Samways Philip P. Frenzel 《Biodiversity and Conservation》2016,25(10):1921-1935
Human demands have led to an increased number of artificial ponds for irrigation of crops year-round. Certain insect species have established in these ponds, including dragonflies (Insecta: Odonata). There has been discussion around the value of artificial ponds for encouraging dragonfly diversity, with little work in biodiversity hotspots rich in rare and endemic species. We focus here on the Cape Floristic Region (CFR) global biodiversity hotspot, which has many endemic dragonfly species but has few natural ponds. Yet it has many artificial ponds mostly used for irrigation on local farms. This leads to an interesting question: to what extent do these artificial ponds provide habitats for dragonflies in this biologically rich, agriculturally fragmented landscape? To answer this, we recorded dragonfly species richness and abundances from 17 artificial ponds and 13 natural stream deposition pools as reference, in an area of the CFR where there are no local, natural, perennial ponds. Thirteen environmental and physical variables were recorded at the ponds and pools. We found that although ponds attracted no rare or threatened dragonfly species, they increased the area of occupancy and population sizes of many generalist species. These came from nearby natural deposition pools or from unknown sources elsewhere in the region, so providing refuges which otherwise would not be there. Interestingly, some CFR endemic species were also recorded at our artificial ponds. Overall dragonfly assemblages and those of true dragonflies (Anisoptera) and damselflies (Zygoptera) differed between artificial ponds and deposition pools, suggesting that artificial ponds are to some extent a novel ecosystem. Habitat type, elevation and temperature were significant drivers in structuring overall species assemblages. For the Anisoptera, riparian vegetation and level of landscape connectivity was important, while temperature was not. In contrast, Zygoptera species were most affected by river catchment, habitat type and temperature. In sum, these artificial ponds are stepping stone habitats across an increasingly fragmented landscape. Managing these ponds with perennial water, constant water levels, and maximum complexity and heterogeneity of habitats in terms of vegetation will conserve a wide range of generalists and some specialists. 相似文献
4.
Mountains present particular challenges for biodiversity conservation. Table Mountain is a significant mountain in a global
biodiversity hotspot, the Cape Floristic Region. It has outstanding angiosperm diversity and endemism. Yet, aerial and foliage
invertebrates in the area have been poorly studied, despite their importance as pollinators and predators. These plant and
invertebrate assemblages are under great pressure from human disturbance. Aerial and foliage invertebrates were sampled with
a range of techniques. Sites were chosen to make comparisons between vegetation structure and type, elevation and aspect.
In total, 216 species from 63 families and 14 orders were recorded. Vegetation structure (fynbos or forest) and elevation
were the most important environmental variables for both aerial and foliage invertebrates. Peak time for aerial invertebrate
abundance was spring and summer in the fynbos and spring in the forests, while the foliage invertebrates showed very little
seasonal variation. There was no correlation between the diversity of aerial and foliage invertebrates. When these results
were compared with others on epigaeic invertebrates, it became clear that epigaeic and aerial invertebrates are not correlated,
while epigaeic and foliage invertebrates were only partially correlated, but not sufficiently so to consider one as a reliable
estimator of the other. The management pointer from this study is that sites at all elevations are vital for the conservation
of biodiversity on Table Mountain. Both the aerial and epigaeic/foliage invertebrate assemblages will need to be monitored
separately to maintain the mountain’s conservation status. 相似文献
5.
Trindade Diego Pires Ferraz Pärtel Meelis Carmona Carlos Pérez Randlane Tiina Nascimbene Juri 《Biodiversity and Conservation》2021,30(8-9):2565-2579
Biodiversity and Conservation - Mountains provide a timely opportunity to examine the potential effects of climate change on biodiversity. However, nature conservation in mountain areas have mostly... 相似文献
6.
Mahesh Sankaran 《Biodiversity and Conservation》2009,18(4):1099-1115
For any conservation strategy to be effective, it must be preceded by knowledge of how diversity is configured within the
area of interest. Here, data from 40 savanna-grassland sites were used to examine how plant biodiversity and species composition
varied across spatial scales at the Kalakad-Mundanthurai Tiger Reserve (KMTR), south India. Grasslands surveyed contained
278 plant species, and were characterized by high spatial variability in species association patterns. Fourteen distinct community
assemblages were identified, organized primarily along an elevation gradient in the reserve. Overall, grasslands at KMTR were
characterized by the dominance of a few, widespread species. The bulk of species richness, however, resulted from subordinate
species with fairly restricted distributions. At low elevations, grasslands had high species richness and species composition
differed greatly between sites. Mid-elevation grasslands contained about half the number of species present at low elevations,
but sites were more similar in species composition. Richness of high-elevation grasslands was a third of that found at low
elevations, but different sites harbored unique sets of species. Herbivore use of grasslands varied between communities and
showed patterns that coincided with elevation. Herbivore use of low-elevation communities was high albeit variable, of mid-elevation
sites was consistently low, and increased at higher elevations. Tall grass communities were the least utilized by herbivores
at all elevations. Most species surveyed were rare and restricted in their distribution suggesting that conservation efforts
must, perforce, encompass the entire reserve. However, differences in the structuring of diversity across elevations, and
in herbivore use of grasslands, suggest that conservation efforts can be partitioned differentially across locations, specifically
targeting low and high elevation grasslands in the reserve. 相似文献
7.
Javier Francisco-Ortega Eugenio Santiago-Valentín Pedro Acevedo-Rodríguez Carl Lewis John Pipoly Alan W. Meerow Mike Maunder 《The Botanical review》2007,73(3):183-234
The Caribbean Island Biodiversity Hotspot is composed primarily of the Bahamas and Greater and Lesser Antilles. A total of
180 genera (727 spp., ca. 9% of the species endemic to the Antilles) are restricted to this hotspot. Most of these genera
are unispecific (51%), a pattern that is also found on other islands of the world. The majority of the endemic genera belong
to the “Core Eudicot” clade, and they were published in two time periods (1854–1878 and 1904–1928). There are molecular phylogenies
available for 63 of the endemic genera. However, phylogenetic reconstructions of only 21 genera are based on more than one
independent DNA region and have well-supported clades and good taxonomic sampling. Six of the endemic genera form part of
early-branching groups. We could not infer biogeographical conclusions from the molecular phylogenies of most of the endemic
genera (43: 68%). There is an urgent need for (1) additional field studies to learn the conservation status of these genera,
(2) effective protection of the habitats where the most endangered genera occur, and (3) additional biological and systematic
studies of the least understood genera. 相似文献
8.
9.
While compositional diversity is a common metric for assessing human impacts on aquatic communities, functional diversity is scarcely employed, though highly desirable from the perspective of the European Water Framework Directive. Using abundance data from 99 minimally disturbed sites (i.e., no or very weak anthropogenic impact) from a national survey, we studied the spatial variability of compositional and functional biodiversity metrics across a predefined ecoregional classification. Metrics of compositional diversity comprised taxonomic and EPT richness and Simpson diversity. Functional diversity metrics were based on Rao's Quadratic Entropy (RQE), which described the differences among benthic invertebrate genera in eleven biological traits (e.g., size, life cycle, reproduction types, feeding habits). Using generalized linear models we show that taxonomic richness may vary greatly across ecoregions, contrasting with Simpson diversity and functional metrics that varied weakly in response to natural environmental variability. Functional diversity metrics, because of their stability in response to natural environmental variability, may be useful tools for assessing human impairment to ecosystem function. We further tested the response of functional diversity metrics to a specific human impact (sewage) and demonstrated significant modifications of functional diversity downstream of sewage pollution. Further investigations are required to test the ability of functional diversity metrics to precisely and accurately indicate different types of human impacts. 相似文献
10.
Global knowledge about the spatial distribution of species is orders of magnitude coarser in resolution than other geographically-structured environmental datasets such as topography or land cover. Yet such knowledge is crucial in deciphering ecological and evolutionary processes and in managing global change. In this review, we propose a conceptual and cyber-infrastructure framework for refining species distributional knowledge that is novel in its ability to mobilize and integrate diverse types of data such that their collective strengths overcome individual weaknesses. The ultimate aim is a public, online, quality-vetted 'Map of Life' that for every species integrates and visualizes available distributional knowledge, while also facilitating user feedback and dynamic biodiversity analyses. First milestones toward such an infrastructure have now been implemented. 相似文献
11.
The Noah's Ark Problem (NAP) is a comprehensive cost-effectiveness methodology for biodiversity conservation that was introduced by Weitzman (1998) and utilizes the phylogenetic tree containing the taxa of interest to assess biodiversity. Given a set of taxa, each of which has a particular survival probability that can be increased at some cost, the NAP seeks to allocate limited funds to conserving these taxa so that the future expected biodiversity is maximized. Finding optimal solutions using this framework is a computationally difficult problem to which a simple and efficient "greedy" algorithm has been proposed in the literature and applied to conservation problems. We show that, although algorithms of this type cannot produce optimal solutions for the general NAP, there are two restricted scenarios of the NAP for which a greedy algorithm is guaranteed to produce optimal solutions. The first scenario requires the taxa to have equal conservation cost; the second scenario requires an ultrametric tree. The NAP assumes a linear relationship between the funding allocated to conservation of a taxon and the increased survival probability of that taxon. This relationship is briefly investigated and one variation is suggested that can also be solved using a greedy algorithm. 相似文献
12.
India's biodiversity hotspot under anthropogenic pressure: A case study of Nilgiri Biosphere Reserve
Nagarajan Baskaran Uthirapathi Anbarasan Govindasamy Agoramoorthy 《Journal for Nature Conservation》2012,20(1):56-61
This paper presents data on the impact of biotic pressure in terms of grazing by livestock and wood cutting by humans on the plant community in the Nilgiri Biosphere Reserve of India. Grass, and herbaceous plant biomass, number of cattle dung piles, number of woody stems available and damaged by human activities and weed biomass were assessed at different proximity along transects radiating from village-forest boundary to forest interior to measure the ecological impact of livestock grazing and fire wood collection. The grass biomass was positively correlated to overgrazing indicating the adverse effect on natural vegetation by cattle. Woodcutting was intense along the forest boundary and significantly declined as distance increased. Similarly, weed biomass and number of thorny species declined positively with proximity from village-forest boundary and the weed biomass was significantly higher in the pastoral sites compared to residential sites. The results suggest that human impact adversely affects natural vegetation and promotes weed proliferation in forest areas adjoining human settlements in the ecologically important Nilgiri Biosphere Reserve. Continued anthropogenic pressure could cause reduction in fodder availability to large herbivores like elephants, which in turn leads to an increase in human–elephant conflict. 相似文献
13.
Imminent shifts in environmental parameters due to climatic change might have profound ramifications for wetlands listed under the Ramsar convention. Although the exact mechanisms by which global change will affect these systems are not known, models that simulate component drivers, particularly at a broad spatial scale, can nevertheless allow for more informed conservation decision making. Such general inference is particularly needed for wetlands across the tropics, where less knowledge and fewer resources are available to mitigate the impacts on important conservation sites. Here we develop a case study of wetland loss to sea level rise across tropical north Australia (including Ramsar‐listed sites), and link these to a metapopulation model for a keystone endemic waterbird, the magpie goose Anseranas semipalmata. We projected published models on sea level rise through to the year 2400, and found a non‐linear trajectory of inundation up to 20 m above present levels. Digital elevation models were used to simulate sea level rise and the spatially differentiated loss of wetland habitat used by geese. Range retraction was linked to decline in ecological carrying capacity, and we coupled wetland‐specific habitat loss projections to a spatially explicit demographic metapopulation model. Additionally, we included alternate harvest strategies based on present‐day estimates of indigenous and non‐indigenous offtake of geese, and examined the synergy between wetland loss and hunting on extinction risk. Our results suggest that Australia's once‐abundant and widespread magpie goose will be reduced to a fragmented population of just a few thousand individuals within the next 200–300 yr. Harvest could continue for some time, up to a “tipping point” at around 5% loss of current wetland habitat, after which the decline of geese is rapid. Given the inexorable nature of sea level rise, short‐ to medium‐term conservation of waterbirds across Ramsar wetlands must prepare for adaptive wetland management, such as through buffer‐placement, and ongoing monitoring of harvest. 相似文献
14.
A sample of 204 skinks (Squamata: Scincidae) from 10 genera representing 24 species were collected from 10 different localities in New Guinea and examined for blood parasites. Hemogregarines, trypanosomes, microfilarial worms, and 8 infections showing 2 distinct morphological types of malaria parasites (Plasmodium sp.) were observed. Molecular sequence data, in the form of mitochondrial cytochrome b sequences from the Plasmodium infections, showed 2 distinct clades of parasites, 1 in Sphenomorphus jobiense hosts and 1 in Emoia spp., which correspond to the 2 morphotypes. There was substantial genetic variation between the 2 clades, as well as within the clade of Emoia parasites. Nearly half of the skinks sampled had green blood pigmentation, resulting from the presence of biliverdin in the plasma; however, only 1 of these lizards was infected with Plasmodium sp. and only 2 had any blood parasites. These preliminary results suggest a high degree of phylogenetic diversity but a very low prevalence of Plasmodium spp. infections in the skinks of this globally important biodiversity hot spot. 相似文献
15.
Sampling bias and the use of ecological niche modeling in conservation planning: a field evaluation in a biodiversity hotspot 总被引:2,自引:0,他引:2
Gabriel C. Costa Cristiano Nogueira Ricardo B. Machado Guarino R. Colli 《Biodiversity and Conservation》2010,19(3):883-899
Ecological niche modeling (ENM) has become an important tool in conservation biology. Despite its recent success, several
basic issues related to algorithm performance are still being debated. We assess the ability of two of the most popular algorithms,
GARP and Maxent, to predict distributions when sampling is geographically biased. We use an extensive data set collected in
the Brazilian Cerrado, a biodiversity hotspot in South America. We found that both algorithms give richness predictions that
are very similar to other traditionally used richness estimators. Also, both algorithms correctly predicted the presence of
most species collected during fieldwork, and failed to predict species collected only in very few cases (usually species with
very few known localities, i.e., <5). We also found that Maxent tends to be more sensitive to sampling bias than GARP. However,
Maxent performs better when sampling is poor (e.g., low number of data points). Our results indicates that ENM, even when
provided with limited and geographically biased localities, is a very useful technique to estimate richness and composition
of unsampled areas. We conclude that data generated by ENM maximize the utility of existing biodiversity data, providing a
very useful first evaluation. However, for reliable conservation decisions ENM data must be followed by well-designed field
inventories, especially for the detection of restricted range, rare species. 相似文献
16.
The ancient landscape of the South - West Australian Floristic Region (SWAFR) is characterized by exceptional floristic diversity, attributed to a complex mosaic of nutrient - impoverished soils. Between - soil type differences in nutrient availability are expected to affect floristic assemblage patterns in the SWAFR. We compared patterns of floristic diversity between open - forest samples from three soil types in the high - rainfall zone of the SWAFR. The importance of environmental and spatial factors for species compositional turnover within soil types were evaluated within canonical correspondence analyses using variation partitioning. Patterns of phylogenetic diversity and dispersion were contrasted between soil types and related to differences in soil nutrient availability. Between - quadrat shared phylogenetic branch length for individual life form categories was correlated with explanatory variables using Mantel tests. Species and phylogenetic diversity increased with a decline in soil nutrients and basal area. Nutrient - poorer soils were differentiated by higher species density and phylogenetic diversity, and larger phylogenetic distances between species. Species turnover was best explained by environmental factors when soil nutrient concentrations and basal area were low. Coastal and inland quadrats from the most fertile soil type were distinguished by significantly differing patterns of phylogenetic diversity. Inland quadrats were characterized by strong relationships between phylogenetic diversity and environment, while phylogenetic patterns remained largely unaccounted for by explanatory variables within coastal quadrats. Phylogenetic diversity was more strongly related with environment within upland landform types for nutrient-poor soils. We highlight the complex relationships between climatic and edaphic factors within the SWAFR, and propose that the occurrence of refugial habitat for plant phylogenetic diversity is dynamically linked with these interactions. Climate change susceptibility was estimated to be especially high for inland locations within the high - rainfall zone. Despite the strong relationship between floristic diversity and soil fertility, holistic conservation approaches are required to conserve the mosaic of soil types regardless of soil nutrient status. 相似文献
17.
The rainbowfishes of the family Melanotaeniidae represent one of the largest radiations of freshwater fishes from the Indo-Australian archipelago. A total of 75 nominal species have been described, among which several have become very popular among tropical fish hobbyists because of their tendency to form large schools of colourful individuals. Facing habitat loss and competition or predation by introduced species, this group has become a priority in the conservation of ornamental fishes in Indonesia. In this context, several expeditions have been conducted between 2007 and 2010 in Indonesian Papua with the aim to initiate a large-scale survey of the genetic resources in this group. We assessed the diversity of the Papua rainbowfishes with DNA barcoding. We sequenced the mitochondrial COI gene for 350 specimens belonging to 53 nominal species throughout the Indo-Australian archipelago. Unexpected levels of cryptic diversity and endemism were detected since additional cryptic lineages were detected in several watersheds from the Vogelkop and the Lengguru massif. DNA barcoding supports the presence of nearly 30 evolutionary lineages among the 15 nominal species sampled in the Vogelkop and all these lineages are endemic to a single lake or watershed. This result highlights that the diversity of the family has been largely underestimated and urges for the identification of conservation priorities in Papua. 相似文献
18.
19.
Rob Bugter Paula Harrison John Haslett Rob Tinch 《Biodiversity and Conservation》2018,27(7):1549-1560
This Editorial to the BESAFE special issue introduces the project and its approach and case studies. The BESAFE (EC 7th Framework programme) project investigated how the effectiveness of different types of arguments for biodiversity conservation depends on the context in which they are used. Our results show that tailoring of argumentation to audience within the course of decision processes is the main factor determining effectiveness. We consistently found arguments linked to intrinsic value (e.g. moral or ethical obligation arguments) as shared and supported widely, and thus offering common ground between parties. Economic arguments are effective as additional ones, but not as replacements. Next generation biodiversity conservation strategies can probably improve their effectiveness by emphasizing and better explaining the synergies between traditional conservation and especially regulating and cultural services. 相似文献
20.
Javier Velzquez Rosario Tejera Ana Hernando María Victoria Núez 《Journal for Nature Conservation》2010,18(4):309-317
The conservation of biodiversity in Europe is defined by Directive 92/43/EEC – commonly known as the Habitats Directive – relating to the conservation of natural habitats and of wild flora and fauna. This Directive established the creation of an ecological network of European protected areas – the Natura 2000 network – , and also recognised the need to manage these areas to maintain their “favourable conservation status”.This paper proposes a methodology which enables the conservation of biodiversity to be integrated into the management of Natura 2000 forest spaces. The methodology comprises an “environmental diagnosis” in three phases. The first phase evaluates the current conservation status of habitats using the following criteria: vital functions; floristic richness; forest structure; area occupied by the habitat; and recovery capacity. The second phase assesses the fragility of the space to determine the degree of vulnerability of habitats. This involves evaluating the fire hazard, erosion hazard, and the fragility of the vegetation. The last phase combines the two previous ones to generate management areas (optimum, intermediate or unfavourable) and to prioritise management actions.This methodology was applied in a protected forest area in the Natura 2000 network, located in Avila (Spain). Different management areas were generated for biodiversity conservation, and each habitat was associated to one of them. Finally, actions were prioritised and designed to raise the habitats to a “favourable conservation status”. 相似文献