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41.
Urban Domestic Gardens (IV): The Extent of the Resource and its Associated Features 总被引:11,自引:0,他引:11
Kevin?J.?GastonEmail author Philip?H.?Warren Ken?Thompson Richard?M.?Smith 《Biodiversity and Conservation》2005,14(14):3327-3349
Domestic (‘private’) gardens constitute a substantial proportion of ‘green space’ in urban areas and hence are of potential
significance for the maintenance of biodiversity in such areas. However, the size and nature of this resource and its associated
features are poorly known. In this study, we provide the first detailed audit, using domestic gardens in the city of Sheffield
as a model study system. Domestic gardens, the mean area of which was 151 m2, cover approximately 33 km2 or 23% of the predominantly urban area of the city. The smaller gardens contribute disproportionately to this total because,
although individually they add little, they are large in number. Conversely, the regions of the city with proportionately
more garden area contribute most to the total garden area of the city, although such regions are limited in number. Based
on the findings of a telephone based survey, 14.4% of dwellings with gardens were estimated to have ponds, 26% to have nest-boxes,
29% to have compost heaps, 48% to hold trees more than 3 m tall, and 14% of dwellings were estimated to be home to one or
more cats. Whilst the absolute frequency of these features is low to moderate, by extrapolation they nonetheless yield estimates
for domestic gardens in Sheffield of a total of 25,200 ponds, 45,500 nest boxes, 50,750 compost heaps, 360,000 trees, and
a population of 52,000 domestic cats. These results are considered in the context of the role of gardens in urban areas as
habitats for wildlife and the implications for housing policy. 相似文献
42.
Marie-Line Maublanc Eric Bideau Romain Willemet Clara Bardonnet Georges Gonzalez Lionel Desneux Nicolas Cèbe Jean-François Gerard 《Comptes rendus biologies》2012,335(12):735-743
We studied the ranging behaviour and spatial relationships between seven roe deer during more than 4 years in a partly wooded 14.2-ha enclosure. The animals (three young males, four adult females) were monitored with GPS telemetry collars. As expected, the surface area and overlap of the males’ bimonthly ranges decreased, and the distance between their arithmetic centres increased, as they became adult and, for two of them, territorial. Unexpectedly, females also tended to space out, the surface area and overlap of their bimonthly ranges being minimal in May to June, i.e. during the birth period. The distance between their arithmetic centres reached its maximum at the same time. Overlap between females’ ranges was consistently lower than those between males and females’ ranges, or between 1-year old males’ ranges. Our results raise the questions of female seasonal territoriality and of independence of the spacing systems of the two sexes in roe deer. 相似文献
43.
Cultivated plant species diversity in home gardens of an Amazonian peasant village in Northeastern Peru 总被引:1,自引:0,他引:1
Research on agrobiodiversity points to the importance of home gardens in situ conservation, yet few studies to date explicate
the origins and dynamics of plant species diversity. In this paper, we examine inter-household variations in cultivated plant
species diversity among house gardens in a traditional peasant community, near Iquitos, Peru. In-depth household interviews
(n = 24) and garden/field surveys reveal that home gardens are clearly the site of highest plant diversity in farmers’ field
portfolios, and that substantial differences exist in garden composition, plant diversity, and the sources of garden planting
material across households. Statistical analyses indicate that home garden diversity is related strongly to specific garden
characteristics, household socioeconomic features, and access to planting material including seeds, cuttings, and suckers.
The role and implications of differential access to planting material in the development and maintenance of crop species diversity
is signaled as an important theme for future study in economic botany. 相似文献
44.
Many conclusions about mammalian ranging behaviour have been drawn based on minimum convex polygon (MCP) estimates of home
range size, although several studies have revealed its unpredictable nature compared to that of the kernel density estimator.
We investigated to what extent the choice of home range estimator affected the biological interpretation in comparative studies.
We found no discrepancy when the question asked covered a wide range of taxa, as real and very large differences in range
size were likely to have masked smaller differences due to the choice of home range estimator. However, when the question
asked concerned within-species characteristics, the choice of home range estimator explained as much of the variation in range
size as did the ecological variable in question. The implications for macro-ecological and intraspecific studies are discussed. 相似文献
45.
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47.
Caroline Birer Corrie S. Moreau Niklas Tysklind Lucie Zinger Christophe Duplais 《Molecular ecology》2020,29(7):1372-1385
Bacteria living on the cuticle of ants are generally studied for their protective role against pathogens, especially in the clade of fungus‐growing ants. However, little is known regarding the diversity of cuticular bacteria in other ant host species, as well as the mechanisms leading to the composition of these communities. Here, we used 16S rRNA gene amplicon sequencing to study the influence of host species, species interactions and the pool of bacteria from the environment on the assembly of cuticular bacterial communities on two phylogenetically distant Amazonian ant species that frequently nest together inside the roots system of epiphytic plants, Camponotus femoratus and Crematogaster levior. Our results show that (a) the vast majority of the bacterial community on the cuticle is shared with the nest, suggesting that most bacteria on the cuticle are acquired through environmental acquisition, (b) 5.2% and 2.0% of operational taxonomic units (OTUs) are respectively specific to Ca. femoratus and Cr. levior, probably representing their respective core cuticular bacterial community, and (c) 3.6% of OTUs are shared between the two ant species. Additionally, mass spectrometry metabolomics analysis of metabolites on the cuticle of ants, which excludes the detection of cuticular hydrocarbons produced by the host, were conducted to evaluate correlations among bacterial OTUs and m/z ion mass. Although some positive and negative correlations are found, the cuticular chemical composition was weakly species‐specific, suggesting that cuticular bacterial communities are prominently environmentally acquired. Overall, our results suggest the environment is the dominant source of bacteria found on the cuticle of ants. 相似文献
48.
49.
George W. LaBar Jose A. Hernando Casal Carlos Fernandez Delgado 《Environmental Biology of Fishes》1987,19(2):111-117
Synopsis Radio telemetry was used to study the movements of European eels,Anguilla anguilla, in a small (1.2 ha) lake in southwestern Spain in March and April, 1985. Observations were taken on the locations of 7 eels at least once each 2 h for a combined total of 1713 h. The size of individual activity regions varied from 2700 to 1300 m2. Eels covered a larger area at night than during the day, with an average of 23% and 42% of the activity region used during the day and night respectively. Average distance moved between observations was significantly greater at night than in the day. Eels tracked during rainy and cloudy weather were more active during the day and used a larger total area than did those tracked during drier, more stable weather. The standing crop of eels was estimated to be about 77 kg ha–1. 相似文献
50.
Thievery,home ranges,and nestmate recognition inEctatomma ruidum 总被引:1,自引:0,他引:1
Summary Thievery of food items among colonies of a ponerine ant,Ectatomma ruidum was common; nonnestmates in colonies or near the colony entrances receive incoming food items and carry them to their own
colony. In our study area 7 of 10 colonies were victimized by thief ants. Colonies have discrete home ranges and home range
size is correlated with the number of workers in the colony. Worker ants discriminate nestmates from non-nestmates when non-nestmates
are presented at colony entrances, but individuals from different colonies were not observed to engage in agonistic interactions
away from nest entrances. Non-nestmates gain entrance to colonies when the entrance is unguarded. Many instances of non-nestmates
being removed from colonies by residents were observed. The costs and benefits of theft under these circumstances are considered. 相似文献