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ROBIN SHARP 《Ibis》1995,137(S1):S219-S223
The Biodiversity Convention requires parties to prepare national plans with strategies for the conservation of biodiversity. The U.K. produced its Action Plan in January 1994, one of the first countries to do so. The document of nearly 200 pages sets out the rationale for conserving biodiversity and the U.K. scientific tradition which underpins our understanding of biodiversity and describes in very summary form the key characteristics of U.K. biodiversity and the resources we devote to sustaining it, both in situ and ex situ, as well as our contribution to assisting conservation outside the U.K. It goes on to consider the role of education and public information and the need to improve the coordination and accessibility of scientific data and monitoring. Finally, it sets out a range of targets and commitments including a proposal to set up machinery, involving non-governmental interests, to agree on specific targets for key species and habitats in 1995. The main emphasis of the Plan and the work ahead is to create a collaborative framework for the large but fragmented efforts by the public voluntary sectors to reverse recent losses of biodiversity. In many ways bird conservation and population monitoring provide a benchmark for other species work. Bird conservation will benefit from the increased integration of effort and scientific analysis which looks at the interaction of species, habitats and wider land use issues and the effect of sectoral policies such as agriculture, energy and transport.  相似文献   

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During 2002–2009, we surveyed butterflies at 73 bogs, 20 adjacent lowland roadsides, and 5 nearby upland roadsides in northern Wisconsin and three bogs in central Wisconsin, with additional observations from 1986 to 2001. Especially in northern Wisconsin, bogs are relatively unaffected by humans, but naturally comprise <1% of the landscape. Bog specialist species composition varied by bog type (muskeg, kettlehole, coastal peatland). Specialist abundance also varied significantly both among bog types and within type among sites. A number of bog specialists frequently occurred in numerous examples of bogs, including all three types. But virtually no specialist individuals occurred in nearby upland roadsides. Northern Wisconsin bogs had similar specialist species richness compared to large barrens and heaths in the same region. Specialist species comprised a small proportion (10%) of all butterfly species recorded in bogs, similar to proportions reported for specialists in tallgrass prairie and barrens. However, specialists accounted for nearly half the total individuals recorded in bogs, comparable to proportions of specialists found in less fragmented vegetation (barrens) and larger patches of favorably managed prairie, but far exceeding proportions observed in other highly fragmented prairie patches. A fundamental lesson may be that aiming to conserve typical ecosystems, even if native, and their average processes, leads to average (generalist) butterflies. Bogs have different vegetation types superimposed on each other, including bog, heath, forest, sedge meadow, and wet meadow associates in the same spots. Conservation management needs to avoid simplifying the vegetation to one layer, reducing specialist fauna. Long-term vegetative consistency, as in bogs, is advised for conservation management of specialist butterflies in other fragmented vegetations.  相似文献   

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Bird conservation in Siberia: a summary   总被引:1,自引:0,他引:1  
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5.
Summary A black oak savanna in central Wisconsin was analyzed in detail, including canopy trees, understory and tree seedlings. Although many authors have held that savanna in this region is a subclimax maintained by fire, this stand, unburned for many years, shows a high degree of stability and very little trend toward the postulated increase in trees. Of the 25 most frequent understory species, 80% have higher affinity for prairie or other very open habitats than for forest. Although oak seedlings had 72% frequency in 1 m2 quadrats, their growth is exceedingly slow, while dieback and mortality are very high; few survive to 1 m in height and saplings are nearly absent. The tree canopy at 40% is low in relation to B. A., probably due to frequent wind and lightning damage. The inhibition of oak seedlings which prevents succession toward forest appears to be caused by a combination of frost, drouth, sandy soil of low water retaining capacity, interspecific competition and allelopathy; seedlings in an adjacent old field grow approximately 3 times faster, with little injury or mortality. Light grazing in early years of settlement may have allowed a temporary increase in tree establishment, since over 2/3 of the present canopy trees appear to be in one age group of 105–110 years. On the basis of this evidence we propose that at least some savanna sites in this region are naturally stable communities maintained by a complex interaction of the local climate, edaphic factors, and the existing community; fire is not an essential factor.
Résumé La Savane à Chêne noir du Wisconsin central est analysée en détail, comprenant arbres, arbustes et semis d'arbres. Beaucoup d'auteurs considèrent cette Savane d?e à l'incendie. Notre groupement pas soumis à l'incendie depuis beaucoup d'années montre un haut degré de stabilité. Des 25 espèces les plus fréquentes du sous-bois 80% montrent davantage d'affinité avec la prairie où d'autres stations ouvertes qu'avec la forêt. Sur une surface de 1 m2 les semis deQuercus ont une fréquence de 72%. Ils poussent très lentement et la mortalité est très grande, la hauteur de la strate arbustive, influencée par les vents fréquents est faible. L'évolution très lente des semis de Chêne semble causée par une combinaison de froid, sêcheresse, sol sablonneux, d'une faible capacité de retenu d'eau, concurrence interspécifique. Dans un vieux champ, les semis poussent à peu près 3 fois plus vite et montrent une plus faible mortalité. Plus de 2/3 des individus de la strate arborescente ont 105–110 ans. Tenant compte de ces faits, nous pouvons admettre qu'au moins certaines Savanes de cette région sont des unités naturelles, stables, maintenues dans cet état par une interaction du climat local, des facteurs édaphiques et de la végétation existante. Le feu n'est pas un facteur essentiel.
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6.
Summary A black oak savanna in central Wisconsin was analyzed in detail, including canopy trees, understory and tree seedlings. Although many authors have held that savanna in this region is a subclimax maintained by fire, this stand, unburned for many years, shows a high degree of stability and very little trend toward the postulated increase in trees. Of the 25 most frequent understory species, 80 % have higher affinity for prairie or other very open habitats than for forest. Although oak seedlings had 72 % frequency in 1 m2 quadrats, their growth is exceedingly slow, while dieback and mortality are very high; few survive to 1 m in height and saplings are nearly absent. The tree canopy at 40 % is low in relation to B. A., probably due to frequent wind and lightning damage. The inhibition of oak seedlings which prevents succession toward forest appears to be caused by a combination of frost, drouth, sandy soil of low water retaining capacity, interspecific competition and allelopathy; seedlings in an adjacent old field grow approximately 3 times faster, with little injury or mortality. Light grazing in early years of settlement may have allowed a temporary increase in tree establishment, since over 2/3 of the present canopy trees appear to be in one age group of 105–110 years. On the basis of this evidence we propose that at least some savanna sites in this region are naturally stable communities maintained by a complex interaction of the local climate, edaphic factors, and the existing community; fire is not an essential factor.
Résumé La Savane à Chêne noir du Wisconsin central est analysée en détail, comprenant arbres, arbustes et semis d'arbres. Beaucoup d'auteurs considèrent cette Savane d?e à l'incendie. Notre groupement pas soumis à l'incendie depuis beaucoup d'années montre un haut degré de stabilité. Des 25 espèces les plus fréquentes du sous-bois 80 % montrent davantage d'affinité avec la prairie où d'autres stations ouvertes qu'avec la forêt. Sur une surface de 1 m2 les semis deQuercus ont une fréquence de 72 %. Ils poussent très lentement et la mortalité est très grande, la hauteur de la strate arbustive, influencée par les vents fréquents est faible. L'évolution très lente des semis de Chêne semble causée par une combinaison de froid, sêcheresse, sol sablonneux, d'une faible capacité de retenu d'eau, concurrence interspécifique. Dans un vieux champ, les semis poussent à peu près 3 fois plus vite et montrent une plus faible mortalité. Plus de 2/3 des individus de la strate arborescente ont 105–110 ans. Tenant compte de ces faits, nous pouvons admettre qu'au moins certaines Savanes de cette région sont des unités naturelles, stables, maintenues dans cet état par une interaction du climat local, des facteurs édaphiques et de la végétation existante. Le feu n'est pas un facteur essentiel.
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7.
《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   

8.
In the face of the continuing global biodiversity loss, it is important not only to assess the need for conservation, through e.g. gap analyses, but also to seek practical solutions for protecting biodiversity. Environmentally and socially sustainable tourism can be one such solution. We present a method to spatially link data on conservation needs and tourism-based economic opportunities, using bird-related tourism in Peru as an example. Our analysis highlighted areas in Peru where potential for such projects could be particularly high. Several areas within the central and northern Andean regions, as well as within the lowland Amazonian regions of Madre de Dios and Loreto emerge as promising for this type of activity. Mechanisms to implement conservation in these areas include e.g. conservation and ecotourism concessions, private conservation areas, and conservation easements. Some of these mechanisms also offer opportunities for local communities seeking to secure their traditional land ownership and use rights. (Spanish language abstract, Abstract S1).  相似文献   

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The worldwide increase of urbanization requires better knowledge of its effects on biodiversity. We investigated the distribution of 41 breeding bird species of conservation concern along an urban gradient (centre, inner periphery, outer periphery, sparsely built up area) in Italian towns. We used data on the presence of bird species of conservation concern in each square of the grid of 27 urban atlases to obtain the frequency of each species in each sector. The frequency of species of conservation concern—for both passerines and non passerines—decreased in more urbanised sectors. An increased degree of urbanization is particularly unfavourable to the following groups of species of conservation concern: raptors (except Falco tinnunculus); galliforms; granivorous, ground-nesting passerines; and passerines of bush-shrub habitats. Our findings did not change substantially if we limited our analysis to small, intermediate or large towns. Our results confirm that urban areas are avoided by the majority of specialists and rare species. However, the frequency of aerial feeders and Jynx torquilla, Phoenicurus phoenicurus, Monticola solitarius and Muscicapa striata did not decrease in more urbanised sectors. Since these species include some whose main habitats are dwindling, urban areas might be a refuge for them. Conservation efforts in towns should preserve the conditions (presence of mature trees, habitat heterogeneity, availability of insects, suitable nesting sites in buildings) favouring these species.  相似文献   

11.
The lowland areas of the Himalayan region are subjected to immense anthropogenic pressure because of least representation in the protected area network. Kitam Bird Sanctuary is the only representative protected area that occurs below 1000 m in Sikkim state of India (a part of globally significant biodiversity hotspot of Himalayas) and serves as the refuge for various species of flora and fauna. Here we studied butterfly diversity and community composition in Kitam Bird Sanctuary (a small protected area of 6 km2 geographical area) following point count method spread across predetermined transects. Altogether 1674 butterflies belonging to 111 species and six families were recorded after completion of 240 point counts. Among these, 18 species are federally protected under the Wildlife (Protection) Act (1972) of India. Most of the butterflies were forest specialist in terms of habitat preference, whereas based on host plant specificity, the butterfly community was mostly dominated by generalist feeder (Oligophagous II and Polyphagous). Butterfly community parameters showed a strong correlation with habitat variables. While Kitam Bird Sanctuary is primarily designated for conservation of lowland birds, the high diversity of butterflies both in terms of taxonomic richness and trait composition suggests that the sanctuary harbors an ideal habitat for butterflies of the tropical region and invites conservation attention.  相似文献   

12.
Land use change alters species' abundance and distributions by affecting habitat availability and quality. The decline of bird populations worldwide is of major concern, and habitat protection and restoration are primary conservation actions. However, conservation decisions largely consider only short-term habitat changes and species’ population dynamics in a given area. Disregarding long term modifications in species’ available habitat, and the role of a given population for a species’ global population may lead to misdirected conservation action. Our goal here was to combine the assessment of conservation responsibility, with that of century-long available habitat dynamics, in order to inform better conservation practice. We compiled available habitat data for 170 bird species in the Carpathian Region from 1860 to 2010 from historic maps and satellite data. We analyzed these species’ range distributions, IUCN extinction risk and population trends, and we identified 29 species of high conservation responsibility, and all of them were forest or and grassland specialists. Furthermore, we found major land use trends including cropland abandonment and increase in forests and grasslands that resulted in increases in potential habitat for the species for which the Carpathians have high conservation responsibility. The loss of row-crop agriculture, on the other hand, reduced habitat for species for which the Carpathians do not have high responsibility, and thus subsidizing agriculture may not be warranted from a conservation perspective. More broadly, many regions worldwide are undergoing rapid land use changes, and we suggest that these should be analyzed relative to a given regions’ conservation responsibility to see if there are opportunities for conservation, i.e., cases similar to the Carpathians, where conservation efforts ‘only’ have to foster current land use trends, and make them permanent, rather than to try to revert the loss of habitat.  相似文献   

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1. We tested the degree to which a lake's landscape position constrains the expression of limnological features and imposes a characteristic spatial pattern in a glacial lake district, the Northern Highland Lake District in north‐central Wisconsin. 2. We defined lake order as a metric to analyze the effect of landscape position on limnological features. Lake order, analogous to stream order, is based solely on geographical information and is simple to measure. 3. We examined the strength of the relationship between lake order and a set of 25 variables, which included measures of lake morphometry, water optical properties, major ions, nutrients, biology, and human settlement patterns. 4. Lake order explained a significant fraction of the variance of 21 of the 25 variables tested with ANOVA. The fraction of variance explained varied from 12% (maximum depth) to 56% (calcium concentration). The variables most strongly related to lake order were: measures of lake size and shape, concentrations of major ions (except sulfate) and silica, biological variables (chlorophyll concentration, crayfish abundance, and fish species richness), and human‐use variables (density of cottages and resorts). Lake depth, water optical properties, and nutrient concentrations (other than silica) were poorly associated with lake order. 5. Potential explanations for a relationship with lake order differed among variables. In some cases, we could hypothesize a direct link. For example, major ion concentration is a function of groundwater input, which is directly related to lake order. We see these as a direct influence of the geomorphic template left by the retreat of the glacier that led to the formation of this lake district. 6. In other cases, a set of indirect links was hypothesized. For example, the effect of lake order on lake size, water chemistry, and lake connectivity may ultimately explain the relation between lake order and fish species richness. We interpret these relationships as the result of constraints imposed by the geomorphic template on lake development over the last 12 000 years. 7. By identifying relationships between lake characteristics and a measure of landscape position, and by identifying geomorphologic constraints on lake features and lake evolution, our analysis explains an important aspect of the spatial organization of a lake district.  相似文献   

15.
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   

16.
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   

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Diurnal raptor habitat use has conservation implications due to environmental and anthropogenic interactions. Three tree-nesting diurnal raptors, black kites (Milvus milvus), steppe buzzards (Buteo vulpinus) and African fish eagles (Haliaeetus vocifer), were studied from December 2016 to October 2017. The objective was to determine factors influencing diurnal raptor habitat selection and use in and around Chembe Bird Sanctuary of Kalulushi district, Zambia. We surveyed for birds in ten randomly selected 200 × 200 m sample plots in each of the five stratified sampling units (miombo woodland, grasslands, human settlements, Lake Chembe and marsh). Seasons and dietary composition variably influenced the distribution, habitat selection and use by raptors. The three raptors devised a suit of behaviours to curtail challenges associated with seasonal food and water availability, and anthropogenic disturbances. There is a need to promote multi-stakeholder engagement and involvement in raptor conservation.  相似文献   

19.
Summary   Volunteers play an important role in recovery efforts on threatened Australian birds. We surveyed the demography, motivation and preferences of people registered with the Threatened Bird Network, a network dedicated to placing volunteers in recovery efforts. Most were employed or studying and were members of conservation or natural history groups. The main reason for volunteering was an interest in conservation, and most volunteers considered habitat conservation of primary importance. They preferred outdoor projects on highly threatened species and where organizers set clear goals, provided feedback and supervised in a friendly and helpful manner. We also surveyed the recovery projects to determine the extent of volunteer involvement required, and the expectations recovery teams had of volunteers. Volunteers made a major contribution to recovery efforts, with $3.4 million being directed to 32 recovery efforts in the period 1996−2000 − a contribution that has been increasing in recent years. Most activities involved surveying and searching and most activities were available in spring, which coincides with the breeding season of the taxa involved. Volunteers travelled considerable distances, yet only a few projects provided financial support.  相似文献   

20.
ALEXANDER ANDREEV 《Ibis》1995,137(S1):S195-S197
The subcontinent of northeast Asia, defined as the region east of the Lena River between 58o and 72oN (and excluding the Kamchatka peninsula), is 3500 km × 1500 km in area (Fig. 1). Influenced by ice-covered seas, low air temperatures and permafrost, it has a complicated mosaic of habitats, supporting a diverse and unique bird fauna with a number of endemic species and populations.
East of the Verkhoyansk range, the northern limit of continuous coniferous forest retreats southwards and is replaced by two vegetation types unique to northeast Siberia: Larch tundra-forest ( sparse Larix cajanderi ) and tall bush tundra ecotone (dominated by the Shrub Pine Pinuspumila and Bush Alder Alnus fruticosa). Shrub Pine dominates sub-alpine altitudes throughout the interior and coastal ranges, descending in places to sea level.
Coastal habitats include river deltas, brackish water bays, offshore drift ice fields and leads, lagoons, sand spits, marshes, intertidal mudflats, cliffs. offshore islands, upwellings and surface currents. Warmed by the ground water, the permafrost-free interior valleys support lush deciduous woods of Poplar Popubs suaveolens and Korean Willow Chosenia macrolepis . Higher in the mountains, dry lichen tundra and rocky deserts occur.  相似文献   

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