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1.
Customary medicinal plant species used by Australian Aborigines are disappearing rapidly with its associated knowledge, due to the loss of habitats. Conservation and protection of these species is important as they represent sources of novel therapeutic phytochemical compounds and are culturally valuable. Information on the spatial distribution and use of customary medicinal plants is often inadequate and fragmented, posing limitations on the identification and conservation of species-rich areas and culturally valuable habitats.In this study, the habitat suitability modeling program, MaxEnt, was used to predict the potential ecological niches of 431 customary medicinal plant species, based on bioclimatic variables. Specimen locality records were obtained from the Global Biodiversity Information Facility (GBIF) data portal and from Australia's Virtual Herbarium (AVH).Ecological niche models of 414 predicted species, which had 30 or more occurrence points, were used to produce maps indicating areas that were ecologically suitable for multiple species (concordance of high predicted ecological suitability) and having cultural values. For the concordance map, individual species niche models were thresholded and summed. To derive a map of culturally valuable areas, customary medicinal uses from Customary Medicinal Knowledgebase (CMKb) (www.biolinfo.org/cmkb) were used to weight individual species models, resulting in a value within each grid cell reflecting its cultural worth.Even though the available information is scarce and fragmented, our approach provides an opportunity to infer areas predicted to be suitable for multiple species (i.e. concordance hotspots) and to estimate the cultural value of a particular geographical area. Our results also indicate that to conserve bio-cultural diversity, comprehensive information and active participation of Aboriginal communities is indispensable.  相似文献   

2.
Genetic differentiation was investigated in the marine mussels Mytilus californianus Conrad and M. edulis Linn. from the west coast of North America. In allopatry with M. californianus, M. edulis occurs throughout the intertidal zone; however, in microgeographic sympatry its ecological range is restricted to above the M. californianus mussel bed and to patches of substratum opened by natural disturbances within the bed. Over the same geographic scale, the broader-niched M. edulis shows greater among-locality genetic difference and greater levels of polymorphism than M. californianus at two enzyme loci. Genetic differentiation on a geographic basis was investigated in M. californianus at a single rock (on a scale of meters), on an island (on a scale of kilometers), throughout a strait (on a scale of 102 kilometers), and along the west coast of North America (on a scale of 103 km). Differentiation was minimal over the west coast, and could be explained by microhabitat differences in a local area. The minimal differentiation in west coast mussels relative to strong geographic differentiation of M. edulis on the east coast of North America may be related to the steeper latitudinal thermal gradient on the east coast. Local ecologically related microgeographic variation can result in biased and misleading estimates of genetic heterogeneity but microgeographic variation at enzyme loci may not be due to selection at the loci investigated or may even be due to the breeding structure of the mussel populations, as suggested by Tracey et al. (1975).  相似文献   

3.
Summary One color-banded black-capped chickadee flock was studied intensively at a winter feeder in Wisconsin. Flock structure was examined by measuring association among flock members in three ways: spatial proximity, temporal association, and association of individuals during flock movements. Additional information was obtained on aggressive interactions at and near the feeder. By midwinter, the strongest attachments were between males and females who subsequently mated; pair attachments strengthened as the breeding season approached. Lower ranked individuals in the dominance hierarchy showed weaker associations with other flock members in early spring than did more dominant individuals. The strong attachment to the mate may have implications for altruistic behavior within the winter flock.  相似文献   

4.
An inventory of the vascular plants, bryophytes, fungi and terricolous lichens recorded within the different sand-dune communities in Wales has been compiled and a summary of the importance of these different taxonomic groups to the ecology and conservation of sand dunes is provided. The total floristic assemblage amounted to 945 species, with vascular plants representing 439 of these. Fungi unexpectedly formed the next most important group with ca. 289 species, followed by bryophytes (171 species) and terricolous lichens (66 species). However, very few of these species are confined to sand dunes. Of the vascular plants only ca. 7 % (32 species) could be classed as either wholly dependent or strongly associated with sand dunes, whereas up to 13% (22 species) of the bryophytes fell within this category. Of the fungi only 4% (10 species) appear to be restricted to sand dunes, but none of the lichen species could be classed as being either limited to, or strongly associated with, this habitat. Over 9% (91 species) of the total flora are considered to be rare, scarce or endangered within the UK or Europe, and ca. 8% of the vascular plant species are considered to be endemic or near-endemic to Europe. The inventory therefore not only provides an insight in the overall plant diversity of dune systems in Wales, it also gives an indication of the proportion of species that are under threat, and the numbers of species that are more-or-less totally dependent on sand dunes. In the discussion various relevant sand-dune management issues are addressed.  相似文献   

5.
An attempt has been made to evaluate pollution status and aquatic bio-resources of the Moirang river near its mouth in the Loktak Lake. The river water is considered polluted as it has high concentration of free CO2 (14.8 mg/l), nitrite-nitrogen (0.040 mg/l), inorganic phosphorus (0.107 mg/l and faecal coliform bacteria (162/100 ml). Aquatic bio-resources of the river include 24 species of fishes representing 20 genera of 13 families and 16 species of macrophytes representing 14 genera of 9 families. The floral and faunal compositions of the river were mostly widely distributed forms that can survive in polluted environments. Fishery potential and conservation strategies of the river are discussed.  相似文献   

6.
Australia has an extensive coastline extending over 60,000 km through diverse tropical and temperate environments. Indigenous archaeological sites are found along this coastline from the time of earliest settlement at least 50,000 years ago. However, Pleistocene sites are rare owing largely to the destructive impacts of sea-level change associated with the end of the last ice age around 10,000 years ago. After this sites are more numerous but there is variability around the coastline due to the impact of a range of both natural and human factors. Here we focus on six key issues impacting on the development and conservation of coastal archaeological deposits: sea-levels, climate change, cyclones, storms, tsunamis and contemporary human impacts. A number of examples of these impacts are discussed from across Australia. Managing and monitoring of sites has been limited in Australia and geoindicators are discussed as a means of developing a long-term measurement of continuing impacts.  相似文献   

7.
A comprehensive list of 1068 typical littoral plant species and subspecies has been composed. They are considered endemic in a wide sense and are subdivided into widespread, transregional, regional and local endemics, the latter three categories being considered as endemics s.s. For each taxon the distribution, habitat preference, endemic status and conservation status are given. The list, which is available upon request, is summarized in a number of figures and tables, from which it appears that 61% of all species are endemics s.s., that ca. 30% of all species are dune and beach species and another nearly 30% are maritime rock species. Species of wet habitats are concentrated in northern and northwestern Europe, dune species in western and southwestern Europe, western Mediterranean and Black Sea. The conservation status of most species is indicated; 37% is considered threatened. It is concluded that the Bern Convention and the European Habitat Directive offer an entirely insufficient framework for effective conservation action. It is suggested to take the present list as a starting point for a geographical/taxonomical/ecological data base of European coastal endemics.  相似文献   

8.
The participation of private landowners in conservation is crucial to efficient biodiversity conservation. This is especially the case in settings where the share of private ownership is large and the economic costs associated with land acquisition are high. We used probit regression analysis and historical participation data to examine the likelihood of participation of Danish forest owners in a voluntary conservation program. We used the results to spatially predict the likelihood of participation of all forest owners in Denmark. We merged spatial data on the presence of forest, cadastral information on participation contracts, and individual‐level socioeconomic information about the forest owners and their households. We included predicted participation in a probability model for species survival. Uninformed and informed (included land owner characteristics) models were then incorporated into a spatial prioritization for conservation of unmanaged forests. The choice models are based on sociodemographic data on the entire population of Danish forest owners and historical data on their participation in conservation schemes. Inclusion in the model of information on private landowners’ willingness to supply land for conservation yielded at intermediate budget levels up to 30% more expected species coverage than the uninformed prioritization scheme. Our landowner‐choice model provides an example of moving toward more implementable conservation planning.  相似文献   

9.
Environmental and Ecological Statistics - To qualify niche space and niche overlap, the current methods are based on a strict assumption of the normal distribution and restrict dependence to the...  相似文献   

10.
Having studied the definitions of niche proposed by different ecologists, I have proposed a quantitative method of niche which can be applied to plants. Accordingly, the niche of an operational taxonomic unit (OTU) has been described by a mapping from its environmental set to the unit interval [0, 1], which enables a model of niche to be mathematically operational. The concepts of fundamental niche, realized niche, time niche, etc., may be described by using mathematical models related to each other, and the geometrical relationships between them can be revealed by a multi-dimensional surface. The uni-factor models are built upon the condition that the other factors are optimal for OTU, which are particular cases of the multi-factor models. The establishment of the quantitative relationship between these two kinds of models makes it possible to find out the plants' fundamental niche by doing uni-factor experiments. This may simplify the experiments in which the parameters in a practically applied model are to be estimated. The niche index introduced in this paper is related to average level and aftereffect of plant responses to the effects of its environment (i.e. “inertia”), thus it should be the basis of the simulation of plant seed yield and of its environmental evaluation. Accordingly, models of niche index, of plant seed yield, of plant growth and of environmental evaluation have been built which can be applied to the environmental evaluation or the prediction and management of plant (crop) production, etc.As an example of application, the models of wheat yield and its environmental assessment have been established and practically tested. The results of testing the model of wheat yield showed that the relative errors are 8% and 7.2%, respectively, in 1984 and 1986. The results of the environmental assessment of wheat reveal the fact that the insufficiency of the soil moisture at the 2th and 3th stages is the main restriction of the production of the wheat in Dinxi, Gansu Province, China.  相似文献   

11.
It is predicted that climate change will drive extinctions of some reptiles and that the number of these extinctions will depend on whether reptiles are able to change their distribution. Whether the latitudinal distribution of reptiles may change in response to increases in temperature is unknown. We used data on reptile distributions collected during the 20th century to analyze whether changes in the distributions of reptiles in Spain are associated with increases in temperature. We controlled for biases in sampling effort and found a mean, statistically significant, northward shift of the northern extent of reptile distributions of about 15.2 km from 1940-1975 to 1991-2005. The southern extent of the distributions did not change significantly. Thus, our results suggest that the latitudinal distributions of reptiles may be changing in response to climate change.  相似文献   

12.
Forests cover approximately one‐third of Central Europe. Oak (Quercus) and European beech (Fagus sylvatica) are considered the natural dominants at low and middle elevations, respectively. Many coniferous forests (especially of Picea abies) occur primarily at midelevations, but these are thought to have resulted from forestry plantations planted over the past 200 years. Nature conservation and forestry policy seek to promote broadleaved trees over conifers. However, there are discrepancies between conservation guidelines (included in Natura 2000) and historical and palaeoecological data with regard to the distribution of conifers. Our aim was to bring new evidence to the debate on the conservation of conifers versus broadleaved trees at midelevations in Central Europe. We created a vegetation and land‐cover model based on pollen data for a highland area of 11,300 km2 in the Czech Republic and assessed tree species composition in the forests before the onset of modern forestry based on 18th‐century archival sources. Conifers dominated the study region throughout the entire Holocene (approximately 40–60% of the area). Broadleaved trees were present in a much smaller area than envisaged by current ideas of natural vegetation. Rather than casting doubt on the principles of Central European nature conservation in general, our results highlight the necessity of detailed regional investigations and the importance of historical data in challenging established notions on the natural distribution of tree species.  相似文献   

13.
在基株和无性系两个水平上,分析了珍稀濒危植物仙湖苏铁种群在土壤资源上的生态位宽度,以及该种群对土壤资源的潜在利用能力,探讨该种群对资源的利用状况,从而为种群的保护提供科学依据。结果表明,在有机质、全氮、速效磷、速效钾等土壤养分资源轴上,无性系种群的生态位宽度大于基株种群;而且无性系种群比基株种群具有更大的潜在利用土壤资源的能力,说明无性繁殖可能是种群在日益恶化的生境中赖以生态的主要方式。当土壤有机质在3.348%~3.832%、全氮在0.164%~0.186%、速效磷在2.092~2.868mg/kg、速效钾含最在108.34~137.28mg/kg范围之间时,种群分布的个体数最多。因此,抑制周边生境恶化,改善土壤养分结构将有助于促进仙湖苏铁种群的恢复和发展。  相似文献   

14.
We present the first quantitative analyses of dolphinfish (Coryphaena hippurus) foraging habits and trophic interactions with co-occurring yellowfin (Thunnus albacares) and albacore (T. alalunga) tunas in the Southern New England region of the western North Atlantic Ocean. Fish caught by recreational anglers in offshore waters of Massachusetts were sampled during the summers of 2007–2010. Diet analysis revealed that shortfin squid (Illex illecebrosus) and small pelagic crustaceans were principal prey to dolphinfish, yellowfin tuna, and albacore tuna. A wide variety of Sargassum-associated fishes were also important to dolphinfish and yellowfin tuna diets. Dietary (Schoener’s index: 0.82–0.86) and isotopic niche (isotopic ellipse overlap: 53.6–64.7 %) overlap was high, and dolphinfish and tunas occupied equivalent trophic positions (TP = 3.4–3.6). Relative prey size in dolphinfish and yellowfin tuna diets exhibited convergence with ontogeny. Overall, dolphinfish had the greatest isotopic niche width, which was twice as large as yellowfin tuna and three times as large as albacore tuna; dolphinfish also consumed the greatest range of prey sizes. Results quantify dolphinfish trophic interactions in the western Atlantic near the northern extent of their geographical range, and are relevant for ecosystem-based management of the offshore pelagic guild in the context of shifting fish populations and fisheries in response to climate and ecological change.  相似文献   

15.
The past decade has seen an increasing shift in animal communication towards more studies that incorporate aspects of signaling in multiple modalities. Although nonhuman primates are an excellent group for studying the extent to which different aspects of condition may be signaled in different modalities, and how such information may be integrated during mate choice, very few studies of primate species have incorporated such analyses. Here, we present data from free-ranging male rhesus macaques on sex skin coloration (modeled to receiver perception), bark vocal signals, androgen levels, morphometric variables, dominance status, and female mate choice. We show that, consistent with data on females, most intra- and interindividual variation in sex skin appearance occurs in luminance rather than color. Sex skin luminance was significantly correlated across different skin regions. Sex skin luminance did not correlate with the majority of bark parameters, suggesting the potential for the two signals to convey different information. Sex skin appearance was not related to androgen levels although we found some evidence for links between androgen levels and bark parameters, several of which were also related to morphometric variables. We found no evidence that either signal was related to male dominance rank or used in female mate choice, though more direct measures of female proceptive behavior are needed. Overall, the function of male sex skin coloration in this species remains unclear. Our study is among the first nonhuman primate studies to incorporate measurements of multiple signals in multiple modalities, and we encourage other authors to incorporate such analyses into their work.  相似文献   

16.
Although it is recognized that marine wild-capture fisheries are an important source of food for much of the world, the cost of sustainable capture fisheries to species diversity is uncertain, and it is often questioned whether industrial fisheries can be managed sustainably. We evaluated the trade-off among sustainable food production, profitability, and conservation objectives in the groundfish bottom-trawl fishery off the U.S. West Coast, where depletion (i.e., reduction in abundance) of six rockfish species (Sebastes) is of particular concern. Trade-offs are inherent in this multispecies fishery because there is limited capacity to target species individually. From population models and catch of 34 stocks of bottom fish, we calculated the relation between harvest rate, long-term yield (i.e., total weight of fish caught), profit, and depletion of each species. In our models, annual ecosystem-wide yield from all 34 stocks was maximized with an overall 5.4% harvest rate, but profit was maximized at a 2.8% harvest rate. When we reduced harvest rates to the level (2.2% harvest rate) at which no stocks collapsed (<10% of unfished levels), biomass harvested was 76% of the maximum sustainable yield and profit 89% of maximum. A harvest rate under which no stocks fell below the biomass that produced maximum sustainable yield (1% harvest rate), resulted in 45% of potential yield and 67% of potential profit. Major reductions in catch in the late 1990s led to increase in the biomass of the most depleted stocks, but this rebuilding resulted in the loss of >30% of total sustainable yield, whereas yield lost from stock depletion was 3% of total sustainable yield. There are clear conservation benefits to lower harvest rates, but avoiding overfishing of all stocks in a multispecies fishery carries a substantial cost in terms of lost yield and profit.  相似文献   

17.
This study was conducted in Gwayi Valley Conservation Area in Zimbabwe. The objective was to evaluate the level of environmental awareness raising among rural communities resettled by government in a wildlife conservation area and their behavior and actions towards biodiversity conservation. We selected three communities based on the degree of exposure to environmental awareness campaigns by various government departments and non-governmental organizations. This formed a gradient of exposure to environmental awareness campaigns, ranging from the most accessible and exposed community (Hangano), moderately exposed (Gwayi) through to the least accessible and exposed community (Karna). We used focus group discussions, key informant interviews and structured interviews with 95 respondents in the selected communities from November 2016 to April 2017. Through public awareness raising, a number of conservation groups were established including fire and hunting committees, anti-poaching teams and environmental resource monitors. While these groups were found to be either inactive or less effective in Gwayi and Karna, all were found to be very active and effective in Hangano. Similarly, community behavior and actions that caused biodiversity loss such as indiscriminate cutting of live trees, poaching, streambank cultivation, fishing in rivers with nets and use of sledges were much reduced in Hangano than in Gwayi and Karna. Frequent environmental awareness campaigns played a critical role in promoting biodiversity in Hangano. We conclude that substantial gains can be made in environmental conservation by investing more in public awareness campaigns, particularly in developing countries such as Zimbabwe where financial resources for conservation are scarce.  相似文献   

18.
In the coastal waters of Florida (USA) tadpole larvae of the colonial ascidian Ecteinascidia turbinata contain chemicals which make them unpalatable to planktivorous juvenile pinfish Lagodon rhomboides. Experiments demonstrate that the bright organe color of E. turbinata tadpoles is aposematic. Fish that have recently tasted larvae of E. turbinata will not attack the palatable tadpoles of Clavelina oblonga when the latter are dyed organe to resemble larvae of E. turbinata. Tadpoles of E. turbinata that have been mouthed and rejected by fish generally survive to complete a normal metamorphosis. Individual selection explains the evolution of aposematic coloration in E. turbinata better than kin selection. The identity of the defensive chemical is unknown. The unpalatable substance in larvae of E. turbinata is removed by dialysis, indicating that it has a molecular weight less than 14000 d. Larvae are not acidic, nor is the active substance denatured by doiling.  相似文献   

19.
Summary Motivation to fight and willingness to risk the use of dangerous weapons, two factors which can be decisive in predicting the winners of asymmetric animal contests, are readily bluffed in display. When contests are decided by motivation to fight or daring, more reliable information about contest asymmetries may be gained by watching actual fights than by watching displays. By presenting mounts to territorial red-winged blackbirds and scoring how aggressively a territory holder attacks the mount, then recording any subsequent intrusions over established boundaries, I showed that neighbors are likely to intrude upon focal males that fail to attack the mount vigorously. This result suggests that red-winged blackbirds watch contests to assess the RHP of neighbors.  相似文献   

20.
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