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1.
Currently 177 vascular plant species are known or presumed to be obligately associated with water in Peru. Their composition and diversity were surveyed in relationship to their distributions among the natural regions of Peru. Despite considerable aridity, the coastal plains of Peru have important aquatic ecosystems, including marshes in river deltas and mangroves in the far north, near the border with Ecuador; 70 species of aquatic plants are found in this coastal region. The Andean highlands include a great variety of wetlands, plus lakes and rivers; 62 species are found, including eight species of Isoetes, some of which are potentially threatened by extinction. The Amazon region of Peru includes both steep montane rivers in the headwaters and wide floodplains formed by meandering rivers in the lowlands; 102 species are found distributed among these ecosystems, although many additional species are semi-aquatic. Research and conservation strategies for Peru's aquatic plants need to take into account these important regional differences.  相似文献   

2.
《动物学研究》2017,(5):264-280
We conducted four bird biodiversity surveys in the Putao area of northern Myanmar from 2015 to 2017.Combined with anecdotal information collected between 2012 and 2015,we recorded 319 bird species,including two species (Arborophila mandellii and Lanius sphenocercus) previously unrecorded in Myanmar.Bulbuls (Pycnonotidae),babblers (Timaliidae),pigeons and doves (Columbidae),and pheasants and partridges (Phasianidae) were the most abundant groups of birds recorded.Species richness below 1 500 m a.s.l.was higher than species richness at higher elevations.Our results suggest that the current protected areas in this region should be expanded to lower elevations to cover critical conservation gaps.  相似文献   

3.
Bird conservation in Siberia: a summary   总被引:1,自引:0,他引:1  
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Knowledge of the composition of the bird community in Alto Balsas (southwestern Puebla, Central Mexico) is needed for management programs aiming at protection and conservation of bird species and their habitats I studied sites with tropical deciduous forest. Data were obtained during 1666 hours of field work in 238 days from March 1998 to September 2000. Six permanent transect (3.5 km long and 100 m wide; 30 to 40 ha in each transect) were used to determine species richness in the study sites. The Shannon-Wiener diversity index was calculated for each site and Sorensen's index was used to assess similarity between sites. One-way analysis of variance was used to test for differences between sites in species richness and diversity values. A total of 128 species were recorded, Tepexco (n=75, H' = 3.76) and Puente Márquez (n=61, H' = 3.62) were the sites that showed the greatest specific richness and diversity. However, species richness and diversity seasonally patterns were similar among sites (ANOVA p > 0.05), with highest diversity during the rainy season. Most species were resident; 42 were migrants. The avifauna was represented by 30 species associated with tropical deciduous forest and 12 from open habitats or heavily altered habitats. Insectivores were the best represented trophic category, followed by carnivores and omnivores.  相似文献   

6.
Land‐use change is the most important driver of biodiversity loss worldwide and particularly so in the tropics, where natural habitats are transformed into large‐scale monocultures or heterogeneous landscape mosaics of largely unknown conservation value. Using birds as an indicator taxon, we evaluated the conservation value of a landscape mosaic in northeastern Madagascar, a biodiversity hotspot and the center of global vanilla production. We assessed bird species richness and composition by conducting point counts across seven prevalent land‐use types (forest‐ and fallow‐derived vanilla agroforests, woody and herbaceous fallow that are part of a shifting cultivation system, rice paddy, forest fragment and contiguous old‐growth forest). We find that old‐growth forest had the highest species richness, driven by a high share of endemics. Species richness and community composition in forest‐derived vanilla agroforest were similar to forest fragment, whereas fallow‐derived vanilla agroforest was most comparable to woody fallow. The open land‐use types herbaceous fallow and rice paddy had fewest species. Across forest fragments, vanilla agroforests, and woody fallows, endemic bird species richness was positively correlated to landscape‐scale forest cover. We conclude that both fallow‐ and forest‐derived vanilla agroforests play an important but contrasting role for bird conservation: Fallow‐derived agroforests are less valuable but take fallow land out of the shifting cultivation cycle, possibly preventing further degradation. Conversely, forest‐derived agroforests contribute to forest degradation but may avoid total loss of tree cover from forest fragments. Considering the land‐use history of agroforests may thus be a promising avenue for future research beyond the case of vanilla. Abstract in Malagasay is available with online material  相似文献   

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8.
Islands: stability, diversity, conservation   总被引:1,自引:0,他引:1  
Islands present both a diversity and a stability paradox. They are often highly species-poor but have considerable biological interest in terms of extraordinary endemic genera and taxonomically isolated groups. They appear to be stable, as in some cases these organisms have persisted for many millions of years, and having an oceanic climate, extreme climatic events may be comparatively rare. However, when subject to extrinsic (anthropogenic) disturbance they do not appear to be stable, but often suffer catastrophic ecological change. These apparent paradoxes are resolved when it is realized that all these features are consequences of the same island characteristics: biotic isolation and oceanicity. As a result of these two characteristics, far oceanic islands are quantitatively different from continental systems in the nature of their ecological processes, which appear to give rise to an extreme punctuated equilibrium model of evolutionary change. Endemics may be ancient relict endemics displaying prolonged stasis and persistence, or products of adaptive radiation representing rapid punctuational events. A process-based definition of a relict endemic (palaeoendemic) is one whose founding lineage (i.e. the original continental source taxon) has not left any descendents. A corollary of this definition is that the time of divergence between an endemic and its continental sister-group should predate the colonization of the island by the now endemic lineage. An example is Dicksonia arborescens which has been on St Helena for at least 9 Myrs and no longer occurs in the likely source area of Africa. These relict endemics, frequent on islands, are important as the last remnants of tranches of biodiversity that have vanished elsewhere. Island conservation strategies require an integrated understanding of both sides of the diversity and stability paradox so that both island processes and island organisms can be conserved.  相似文献   

9.
The conservation of plants has not generated the sense of urgency—or the funding—that drives the conservation of animals, although plants are far more important for us. There are an estimated 500,000 species of land plants (angiosperms, gymnosperms, ferns, lycophytes, and bryophytes), with diversity strongly concentrated in the humid tropics. Many species are still unknown to science. Perhaps a third of all land plants are at risk of extinction, including many that are undescribed, or are described but otherwise data deficient. There have been few known global extinctions so far, but many additional species have not been recorded recently and may be extinct. Although only a minority of plant species have a specific human use, many more play important roles in natural ecosystems and the services they provide, and rare species are more likely to have unusual traits that could be useful in the future. The major threats to plant diversity include habitat loss, fragmentation, and degradation, overexploitation, invasive species, pollution, and anthropogenic climate change. Conservation of plant diversity is a massive task if viewed globally, but the combination of a well-designed and well-managed protected area system and ex situ gap-filling and back-up should work anywhere. The most urgent needs are for the completion of the global botanical inventory and an assessment of the conservation status of the 94% of plant species not yet evaluated, so that both in and ex situ conservation can be targeted efficiently. Globally, the biggest conservation gap is in the hyperdiverse lowland tropics and this is where attention needs to be focused.  相似文献   

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11.

Background

Zootherapy is important in various socio-cultural environments, and innumerous examples of the use of animal derived remedies can currently be found in many urban, semi-urban and more remote localities in all parts of the world, particularly in developing countries. However, although a number of ethnobiological inventories concerning the use of medicinal animals in human health care have been compiled in Brazil in recent years, zootherapeutic practices in ethnoveterinary medicine (EVM) are poorly described and neglected in favor of human ethnomedicine. In this sense, the purpose of this study was to describe the local zootherapeutic practices in ethnoveterinary medicine of semi-arid of NE Brazil (Caatinga biome) and to contribute to future research about the validation of the effects and side effects of these animal products

Methods

The information obtained through semi-structured interviews was complemented by free interviews and informal conversations. A total of 67 people were interviewed (53 men and 14 women) about the use and commercialization of medicinal animals. To determine the relative importance of each local known species, their use-values (UV) were calculated. Diversity of species utilized was compared, between localities, using rarefaction curves and diversity estimate (Chao2)

Results and Conclusions

A total of 44 animal species (37 vertebrates and 7 invertebrates), distributed among 6 taxonomic categories were found to be used to treat 30 different ailments in livestock and pets. The results of our surveys revealed a rich traditional knowledge of local residents about the use of animals in traditional veterinary medicine. Although it is gradually being discontinued, the perceived efficacy, economic and geographic accessibility were main reasons for popularity of zootherapy in studied areas.  相似文献   

12.
Diversity is a complex term that includes taxonomic, functional, spatial and temporal aspects of organisms variety. Conservation policies must be supported by holistic studies of ecosystem function, must aim to transform scientific knowledge into social responsibility creating a culture of respect towards nature and should also include economic components. Mediterranean ecosystems will likely experience the greatest proportional changes in biodiversity due to the substantial influence of land use and climate change as major drivers. Land use includes not only rural abandonment but also intensive exploitation of native forests (cork oak woodlands) or shrublands for animal or crop production. These last two are dependent on large Nitrogen (N) inputs. In this paper we intend to show the responses of Mediterranean ecosystems to increased N availability in terms of biodiversity and ecosystem functionality. We present two case studies: 1) a gradient of N availability due to a N point source; and 2) N manipulative field experiment (doses and forms). With these results our aim is to pinpoint the importance of improving scientific knowledge at a local level before we establish conservation policies at global level. The two case studies reflect a strong influence of the N source on ecosystem function. Finally, we use the SWOT (Strengths, Weakness, Opportunities and Threats) analysis approach to underpin the complexities of human intervention in the N cycle and the problem it poses for policies of plant conservation.  相似文献   

13.
Mexico has a megadiverse avifauna that includes many endemic elements, as well as rich sets of species ranging farther north or farther south in the Americas. This avifauna, nonetheless, has suffered considerable losses as a consequence of long‐term, intensive human activity across the landscape. We review what is known about the Mexican avifauna, specifically its diversity and endemism, and how that knowledge has and has not turned into effective conservation measures to assure the long‐term integrity of the avifauna.  相似文献   

14.
The Azores Archipelago, located in the North Atlantic Ocean, with an extensive hiking trail system is a promising destination for nature tourism. Hiking is becoming an important touristic attraction, but negative impacts may arise on trails. We aim to evaluate plant biodiversity along eight hiking trails located inside Special Areas of Conservation in two islands with different levels of population density and touristic activity (São Miguel and Flores). Along each trail, 3 plots of 5 × 5 m were used to evaluate the vegetation at every 500 m. Effects of distance to the trail border, altitude, trail, and island, were evaluated by: (i) diversity measures; (ii) floristic composition (different life forms; different biogeographic/conservation status); and (iii) identifying indicator species. Bayesian models run in WinBUGS and the R package “Indicspecies” were used. In total, 111 plant taxa were found, with: (i) highest species richness and diversity in the plots closer to the trail; (ii) highest evenness at the lowest altitude class; (iii) a reduction in the proportion of introduced species with increasing altitude; (iv) a variation in life forms’ composition between and within trails (with the altitude); and (v) the presence of indicator species associated to one altitude, one trail, or one island. The results showed a slight impact on vegetation from the presence of the trails, although with no major changes in the community composition. Presently, factors like the type of land use in areas surrounding the trails may have a deeper effect on plant biodiversity than trail use by visitors.  相似文献   

15.
Analysing healing practices at an ayahuasca tourism centre in Peru, this article illustrates how Shipibo practices of curing and sorcery have adapted to the demands of international clients searching for primitivist healing experiences. At the core of this adaption is the thorny issue of occult power and its relation to capital accumulation. Sorcery here does not serve clients but is manifest among healers working to capitalize on the guests’ primitivist rejections of modern life while operating in environments of economic scarcity and ambient poverty. Ayahuasca tourists do not request and generally do not believe in sorcery, but their very presence generates and negates the local moral economy of sorcery in novel ways. The article explores a paradoxical aspect of ayahuasca tourism wherein guests purge similar anxious desires for capital accumulation that healers achieve when curing them.  相似文献   

16.
Data are presented on the richness of Macrolepidoptera faunas in the Indo-Australian tropics, and on the proportional representation of the various families. Both overall diversity and diversity of families decline with latitude and also with isolation from major land areas. Exceptions are noted.
Measures of alpha-diversity from quantitative light-trap samples indicate that diversity within the tropics is often greatest at altitudes around 1000 m, declining above that level. Diversity is much lower in Pacific archipelagos. Loss of diversity through disturbance and conversion to agriculture is evident and marked. Problems in the measurement of diversity with light-traps are discussed, exemplified by results obtained using different trap types.
Changes in family proportions with habitat type are examined. Family diversity generally decreased with altitude and with disturbance and conversion to agriculture, though there are exceptions to this decline.  相似文献   

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18.
We describe the application of molecular biological techniques to estimate eukaryotic diversity (primarily fungi, algae, and protists) in Antarctic soils across a latitudinal and environmental gradient between approximately 60 and 87 degrees S. The data were used to (i) test the hypothesis that diversity would decrease with increasing southerly latitude and environmental severity, as is generally claimed for "higher" faunal and plant groups, and (ii) investigate the level of endemicity displayed in different taxonomic groups. Only limited support was obtained for a systematic decrease in diversity with latitude, and then only at the level of a gross comparison between maritime (Antarctic Peninsula/Scotia Arc) and continental Antarctic sites. While the most southerly continental Antarctic site was three to four times less diverse than all maritime sites, there was no evidence for a trend of decreasing diversity across the entire range of the maritime Antarctic (60 to 72 degrees S). Rather, we found the reverse pattern, with highest diversity at sites on Alexander Island (ca. 72 degrees S), at the southern limit of the maritime Antarctic. The very limited overlap found between the eukaryotic biota of the different study sites, combined with their generally low relatedness to existing sequence databases, indicates a high level of Antarctic site isolation and possibly endemicity, a pattern not consistent with similar studies on other continents.  相似文献   

19.
To what extent do repair and maintenance of consumer electronics conserve the materials and energy they embody? In this paper we examine the conservation value of a cluster of independent third-party electronics repair businesses in Lima, Peru. Drawing on a combination of methods that include fieldwork, digital methods for online sociology, and life cycle assessment (LCA) of phones and tablets we quantify the conservation value of typical repairs performed at businesses in this cluster in terms of CO2 equivalent (CO2e) and water consumption relative to new manufactures of the same categories of electronics. We model typical repair scenarios and find that repair can offer substantial conservation benefits. However, these benefits vary by device sub-unit repaired (e.g., replacing a camera vs. replacing a display). For example, while two screen repairs through replacement is nearly equivalent to replacement with a whole new device, repairing with components that are already in the market could save around 10% of total emissions in global warming potential (GWP) for both devices. Further, we discuss the politics of attributing the conservation value achieved by the third-party repair cluster in Lima to either domestic (that is, Peruvian) or foreign CO2e and water consumption. Whose conservation of CO2e and water is this? How do the answers to that question shape understandings of the relevance of location for industrial ecology? Our work contributes to the emerging subfield of political industrial ecology and its incorporation of spatially explicit LCAs.  相似文献   

20.
Genetic relationships between 61 dog breeds were investigated, using a sampling of 1514 animals and a panel of 21 microsatellite markers. Based on the results from distance-based and Bayesian methods, breed constituted the main genetic structure, while groups including genetically close breeds showed a very weak structure. Depending on the method used, between 85.7% and 98.3% of dogs could be assigned to their breed, with large variations according to the breed. However, breed heterozygosity influenced assignment results differently according to the method used. Within-breed and between-breed diversity variations when breeds were removed were highly negatively correlated ( r  = −0.963, P  <   0.0001), because of the genetic structure of the breed set.  相似文献   

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