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11.
The home range ofTakydromus tachydromoides was studied in a grassland area from April 1977 to November 1978. The mean size of home range did not differ markedly between sexes; 136.5 m2 for males and 130.8 m2 for females. Home ranges of adults overlapped greatly in each sex, and the lizard was considered to be non-territorial. Individuals showed return movement to a definite area (sleeping site) within the home range, and the home range did not shift within a year or between years. Characteristics of the home range of this grassland-inhabiting lizard were discussed in relation to resource abundance and predation pressure.  相似文献   
12.
The history of botanic gardens in the United Kingdom is sketched out with particular reference to the Royal Botanic Gardens Kew and its changing role to meet societal requirements over 250 years.Kew’s position as a modern scientific institution confronting today’s environmental issues through its Breathing Planet Programme yet retaining its heritage buildings and collections is pinpointed.  相似文献   
13.
In this work we report results of radiotracking studies on the movements and home range sizes of two near-threatened species, the greater rhea (Rhea americana) and the lesser rhea (Pterocnemia pennata pennata) in relation to different land use regimes. We radiomonitored greater and lesser rheas for 3 years in their respective habitats: the Pampas and the Patagonia regions. We chose two study areas in each habitat with similar agricultural activities and different hunting control. We did not find significant differences in movements and home range size between study areas of each species. This suggests that disturbance caused by human presence in the areas did not affect rhea spacing behaviors. Moreover, lesser rheas showed larger home range and movements than greater rheas, showing that the home range size is not an immutable property of body mass, and that abundance and distribution of food appears to be the main factor that influences the movements and home range size of these birds.  相似文献   
14.
Core activity areas are the most important sites within an animal’s home range as they contain the greatest density of critical resources. Because these areas are small and intensively used, they can affect the total distances covered by animals searching for resources. Our objective was to document which habitat variables affect core area selection by female mule deer (Odocoileus hemionus) in an arid environment, and to learn which variables affect their displacement within these areas. Using radiotelemetry, from 2012 to 2014 we monitored seven female mule deer. We estimated their core areas, and with this information we identified and classified the location records as inside or outside of the core area. For each record, we also recorded variables related to time (month, time of day), environmental conditions (temperature, relative humidity), and habitat characteristics (plant association, distance to the nearest water body, slope), and used them to predict the presence of the deer in the core area using Classification and Regression Trees (CART). The same variables were analyzed using a GLM to determine which factors explain variations in displacement distance. The most important variable in core area selection was the distance to the nearest body of water (<933.71 m at the population level and <1375.11 m on average for individual deer), followed by two plant associations that included the dominant species Prosopis glandulosa, Pleuraphis mutica, Larrea tridentata, Opuntia rastrera and Fouquieria splendens in areas with a gentle slope or none. Displacement distances within the core area were shorter than those outside and were affected by time of day and month. Our results are the first to elucidate the use of the core area by female mule deer in the Chihuahuan Desert, and allow us to start understanding the connection between the habitat resources essential to the survival of these deer and their movement under desert conditions.  相似文献   
15.
The results of 100 carpet dust analyses from atopic individuals' environment were compared according to the sampling period or the location. Dust samples were collected with a standard domestic vacuum cleaner, in locations with carpeted floor: in residences (living-room and/or bedroom), in school classrooms and in offices. The quantities of fungi vary from 5000 CFU/g to 66 000 000 CFU/g of dust. More than 100 species were isolated by dilution plating. The main species found in carpet dust wereEurotium repens, Penicillium chrysogenum, Alternaria alternata, Aureobasidium pullulans andPhoma herbarum. Strict xerophilic species were rather rare and detected in small quantities. Differences in the distribution of the CFU concentrations were examined for the four different sampling locations and were statistically significant (P=0.0174). In this study, schools were open spaces, and offices, mostly with air conditioning systems, were locations in which air is not confined. This, added to frequent professional carpet cleaning, probably explains the lowest levels of fungal concentration found in these locations. The majority of the homes had the largest fungal concentration in the living-room (median: 2×105 CFU/g) while some bedrooms (median: 7×104 CFU/g) had the highest concentrations. It is suggested that, when fungi are suspected to be the origin of respiratory allergy or irritating symptoms, the mycoflora of the bedroom, principally, should be investigated first.  相似文献   
16.
When animal home ranges overlap extensively in species lacking overt territorial behaviours, identifying exclusive core areas within individual ranges can be difficult. By analysing the size and overlap of successively smaller core areas among individual Eurasian red squirrels (Sciurus vulgaris), we determined exclusive areas within the home ranges of resident males and females. Possible effects of habitat composition and food supplies were explored by monitoring squirrels in different conifer forests and during years with low and high tree seed production. Using outlier-exclusive cores (OEC) revealed that the total ranges consisted of large sally zones (on average, 35% of the total minimum convex polygon [MCP] range) around home ranges with multi-nucleate cores. The mean OEC home range size did not differ between the sexes but was larger with poor food availability. Home ranges (99% incremental cluster polygons [ICP]) overlapped extensively between sexes (average overlap high food–low food: males by females 21–40%, females by males 43–45%) and among males (males by males 26–44%), while intrasexual overlap among females was low (9–10%). The overlap of inner cores among females rapidly approached zero, suggesting the intrasexual territoriality of 75% core areas. This was not the case among male squirrels, for which intrasexual overlap averaged only 4% at 50% but 18% at 75% core areas. Even the smallest inner cores had some degree of intersexual overlap, indicating that complete territoriality did not occur in this species. Female home ranges were more strongly affected by annual fluctuations in food supplies than male ranges. Females reduced the size of their food-based intrasexual territories when food availability increases. Males probably benefit from using larger home ranges and core areas, which overlap with the ranges of several females, by increasing their probability of successful mating.  相似文献   
17.
Kirk M  Esler D  Iverson SA  Boyd WS 《Oecologia》2008,155(4):859-867
The distribution of predators is widely recognized to be intimately linked to the distribution of their prey. Foraging theory suggests that predators will modify their behaviors, including movements, to optimize net energy intake when faced with variation in prey attributes or abundance. While many studies have documented changes in movement patterns of animals in response to temporal changes in food, very few have contrasted movements of a single predator species naturally occurring in dramatically different prey landscapes. We documented variation in the winter movements, foraging range size, site fidelity, and distribution patterns of a molluscivorous sea duck, the surf scoter (Melanitta perspicillata), in two areas of coastal British Columbia with very different shellfish prey features. Baynes Sound has extensive tidal flats with abundant clams, which are high-quality and temporally stable prey for scoters. Malaspina Inlet is a rocky fjord-like inlet where scoters consume mussels that are superabundant and easily accessible in some patches but are heavily depleted over the course of winter. We used radio telemetry to track surf scoter movements in both areas and found that in the clam habitats of Baynes Sound, surf scoters exhibited limited movement, small winter ranges, strong foraging site fidelity, and very consistent distribution patterns. By contrast, in mussel habitats in the Malaspina Inlet, surf scoters displayed more movement, larger ranges, little fidelity to specific foraging sites, and more variable distribution patterns. We conclude that features associated with the different prey types, particularly the higher depletion rates of mussels, strongly influenced seasonal space use patterns. These findings are consistent with foraging theory and confirm that predator behavior, specifically movements, is environmentally mediated.  相似文献   
18.
朱鹮繁殖期的活动区和栖息地利用   总被引:19,自引:0,他引:19  
20 0 0~ 2 0 0 2年 ,我们应用标记识别法和地理信息系统对朱繁殖期的活动性、活动区和栖息地利用进行了研究。结果表明 :朱在越冬期、繁殖期和繁殖后期的觅食距离存在差异 ,分别为 2 82 1± 1 4 88km、0 5 6 3± 0 6 81km和 1 70 6± 0 834km ,但同一时期中不同个体间的觅食距离无显著差异。不同年份中 ,朱在越冬期和繁殖期的觅食距离无显著差异 ;在繁殖后期 ,由于受到干旱等气候因素的影响 ,两年的觅食距离差异显著。一天中觅食距离最远的是 10 :0 0~ 12 :0 0 ,最近的是 0 6 :0 0~ 0 8:0 0。不同时间段中觅食行为的比例差异显著 ,0 6 :0 0~ 10 :0 0和 16 :0 0~ 18:0 0为取食高峰期 ,中午和夜宿前的休息和理羽行为则高于其他时间段。MCP法和 90 %Kernel法的计算结果表明 ,其中 8只观测次数较多的朱在繁殖期的平均活动区面积分别为10 0 8± 4 9 8hm2 和 175 6± 91 3hm2 ,5 0 %Kernel法计算的活动区的核心面积为 4 3 8± 2 1 5hm2 。朱个体间的繁殖活动区重叠强度较大 ,达到各自活动区的 2 4 5 %± 2 7 3%。朱营巢比较密集 ,配对亲鸟间的活动区重叠强度和其他个体的重叠强度无显著差别。栖息地利用研究表明 ,朱对针阔混交林的利用率显著低于研究区内的可利用率 ,对水田的利用  相似文献   
19.
IntroductionHip fracture is one of the most frequent disabling injuries, presenting serious complications during the acute and subacute phase. Rehabilitation at home, after hospital discharge, allows rapid functional recovery. The objective of this study is to evaluate the possible usefulness of a home rehabilitation program in patients with hip fracture integrated in a Hospital at Home Unit.MethodsRetrospective study that consecutively included patients accepted for home rehabilitation treatment between September 9, 2019 and December 31, 2021 in the Hospital at Home Unit of the Hospital Universitario de la Ribera, Alzira, Valencia. Demographic, clinical, functional and quality of care variables were collected.ResultsTwo hundred twenty-four subjects were included. The mean age was 84.6 (SD 7.7) years, with 66% women and 34% men, with 32% of patients diagnosed with dementia in one of its degrees of severity. The mean hospital stay was 8.4 (SD 4.1) days and 6.5 (5.3) days in the Hospital at Home Unit rehabilitation program. 90% of the patients included in the program reached the therapeutic goal outlined during hospital admission.ConclusionsThe home rehabilitation of patients with hip fracture contributes to a functional recovery of the patient in a shorter time. Further studies are necessary to confirm the results obtained.  相似文献   
20.
Background and Aims Autumn leaf senescence marks the end of the growing season in temperate ecosystems. Its timing influences a number of ecosystem processes, including carbon, water and nutrient cycling. Climate change is altering leaf senescence phenology and, as those changes continue, it will affect individual woody plants, species and ecosystems. In contrast to spring leaf out times, however, leaf senescence times remain relatively understudied. Variation in the phenology of leaf senescence among species and locations is still poorly understood.Methods Leaf senescence phenology of 1360 deciduous plant species at six temperate botanical gardens in Asia, North America and Europe was recorded in 2012 and 2013. This large data set was used to explore ecological and phylogenetic factors associated with variation in leaf senescence.Key Results Leaf senescence dates among species varied by 3 months on average across the six locations. Plant species tended to undergo leaf senescence in the same order in the autumns of both years at each location, but the order of senescence was only weakly correlated across sites. Leaf senescence times were not related to spring leaf out times, were not evolutionarily conserved and were only minimally influenced by growth habit, wood anatomy and percentage colour change or leaf drop. These weak patterns of leaf senescence timing contrast with much stronger leaf out patterns from a previous study.Conclusions The results suggest that, in contrast to the broader temperature effects that determine leaf out times, leaf senescence times are probably determined by a larger or different suite of local environmental effects, including temperature, soil moisture, frost and wind. Determining the importance of these factors for a wide range of species represents the next challenge for understanding how climate change is affecting the end of the growing season and associated ecosystem processes.  相似文献   
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