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1.
The influence of weather on habitat use by small mammals   总被引:1,自引:0,他引:1  
Summer habitat use by three species of forest small mammals was determined using tracking stations Nocturnal weather influenced habitat selection by deer mice and woodland jumping mice but not by red-backed voles Deer mice used all habitats equally on clear nights but were most active in mixed forest on cloudy, rainless nights and most active in a coniferous habitat on rainy nights Jumping mice were most active in mixed forest on clear and rainy nights but shifted to coniferous forest on cloudy dry nights Red-backed voles were most active in the coniferous habitat regardless of weather Microhabitat references within habitats reflected the same preferences as habitat selection Microhabitat selection by jumping mice also changes with weather The mechanism most likely responsible for the observed habitat selection changes is changing insect abundance associated with cloud cover and rainfall  相似文献   

2.
The influence of weather upon the activity of slugs   总被引:2,自引:0,他引:2  
Summary The activity of slugs was measured by a catch per unit effort sampling system based upon night searching, and was related to the microclimatological conditions in the habitat by regression analysis. The activity of Arion hortensis Fér., Arion subfuscus (Drap.), Arion lusitanicus Mab., Milax budapestensis (Hazay), and of all slugs irrespective of species, was found to be best related to temperature and vapour pressure deficit. The relevance of these results to the application of effective methods for the control of slugs is discussed.  相似文献   

3.
Background: In the United States, the prevalence of asthma is not only higher than in most other countries, it also varies greatly between diverse populations. Only limited data exist that examine the variation of outcomes by gender in patients admitted to a hospital for asthma.Objective: This study assessed outcome differences based on gender in adults who were admitted nationally with the primary diagnosis of asthma.Methods: A retrospective cohort study was conducted of all patients who were admitted to a hospital with the primary diagnosis of asthma in 2002-2005 and were reported in the Nationwide Inpatient Sample of the Healthcare Cost and Utilization Project. Patients were excluded if they were aged <18 years or had an additional diagnosis of chronic obstructive pulmonary disease.Results: A total of 590,410 patients (439,991 women, 150,419 men) were included in the study. Patients admitted for asthma were significantly more likely to be female (P < 0.05). Women were significantly older compared with men (mean [SD], 48.5 [17.4] vs 44.6 [17.0] years, respectively), had a longer length of stay (3.44 vs 2.84 days), were more likely to be white (37.9% vs 34.2%), and had a higher total cost of admission ($10,575 vs $9390) (all, P < 0.05). Women were more likely than men to need a tracheostomy (adjusted odds ratio [AOR] = 2.04; 95% CI, 1.77-2.35) and to have a bronchoscopy (AOR =1.12; 95% CI, 1.05-1.21). Men were significantly more likely than women to have arterial blood gases performed (AOR = 1.15; 95% Cl, 1.05-1.27) and to be intubated (AOR = 1.18; 95% Cl, 1.10-1.26) (both, P < 0.05). Men were significantly more likely to be admitted as an emergency admission (AOR = 1.10; 95% Cl, 1.04-1.18) and to die during hospitalization (AOR =1.69; 95% CI, 1.41-2.03).Conclusion: Although they were less likely to be admitted to a hospital, men were more likely to be admitted as an emergency and to experience worse outcomes compared with women, in this study of adults with asthma in the United States.  相似文献   

4.
A study has been made of the annual incidence of asthma in Brisbane for 7 years in relation to the weather. The element most closely associated with asthma was rainfall. There was a minor, independent association with temperature. The association of asthma with rain and warmth, which promote the growth of vegetation, supports the suggestion arising from the seasonal study of asthma that vegetation may be an important source of allergens.
Zusammenfassung Die Beziehung zwischen dem Wetter und der Häufigkeit von Asthma in Brisbane während 7 Jahren wurde untersucht. Unter den meteorologischen Elementen ergab sich die engste Beziehung zwischen Asthmahäufigkeit und Niederschlägen. Eine geringere, unabhängige Beziehung bestand mit der Temperatur. Die Verbindung von Asthma mit Niederschlägen und Wärme stützt die Vermutung, dass die Vegetation eine wichtige Allergenquelle ist.

Resume On a étudié durant 7 années la relation existant entre le temps et la fréquence des crises d'asthme à Brisbane. Parmi les éléments météorologiques examinés, celui qui donna la plus étroite relation est la précipitation.Une relation indépendante, moindre il est vrai, existe également avec la température.L'étroite relation entre les crises d'asthme d'une part, les précipitations et la chaleur d'autre part renforce l'hypothèse que la végétation est la principale source des principes allergènes.
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Since the appearance of western corn rootworm (Diabrotica virgifera virgifera Le Conte) (Coleoptera: Chrysometidae) in Romania, many researchers have been made, in more or less success. In this study we try to clarify the ecology of the species in order to predict its evolution and its potential area of distribution. In Romania, this species was signalled for the first time in 1996, in western part of country neighbouring with Hungary. This region is an important area for maize production for seed and silage. Together, the climatic conditions, altitude and their influence on species behaviour and distribution have become more apparent. Their habitat and survival strategies are strongly dependent on local weather patents and altitude. In order to investigate the potential impact of weather and altitude on pest populations, a clear understanding of the nature and characterization of pest is required. In general, most pest species are influenced by warm, rainfall and altitude. Taking into consideration our data from the years 2008 and 2009, we can emphasize a very serious influence of air temperature, rainfall and altitude on WCR flight dynamics in adults. Dry and warm conditions generally lead to increasing of insects' number. Our data shown positive correlations between air temperature (daily mean) and adults number captured on pheromone traps (daily mean), but the there are limits from which these become negative. The same trend was recorded in previous research period (2004-2006). The rainfall is an important factor that influences adults' dynamics in maize fields. Excessive rainfall leads to adults' number decreasing. Our daily observations showed a decreasing number of beetles while rainfall increases. Regarding the altitude, we observed a decreasing number of WCR adults at once the attitude increase. For capture of adults we used pheromone traps, in 3 replications (T1, T2 and T3) at difference altitude where maize was grown. Significant relationship of WCR flight dynamic with weather and geographical conditions were found. Activities were carried out under the PN-II-ID-PCE-2007-1/RO project.  相似文献   

7.
By altering its flight altitude, a bird can change the atmospheric conditions it experiences during migration. Although many factors may influence a bird's choice of altitude, wind is generally accepted as being the most influential. However, the influence of wind is not clearly understood, particularly outside the trade‐wind zone, and other factors may play a role. We used operational weather radar to measure the flight altitudes of nocturnally migrating birds during spring and autumn in the Netherlands. We first assessed whether the nocturnal altitudinal distribution of proportional bird density could be explained by the vertical distribution of wind support using three different methods. We then used generalized additive models to assess which atmospheric variables, in addition to altitude, best explained variability in proportional bird density per altitudinal layer each night. Migrants generally remained at low altitudes, and flight altitude explained 52 and 73% of the observed variability in proportional bird density in spring and autumn, respectively. Overall, there were weak correlations between altitudinal distributions of wind support and proportional bird density. Improving tailwind support with height increased the probability of birds climbing to higher altitude, but when birds did fly higher than normal, they generally concentrated around the lowest altitude with acceptable wind conditions. The generalized additive model analysis also indicated an influence of temperature on flight altitudes, suggesting that birds avoided colder layers. These findings suggested that birds increased flight altitudes to seek out more supportive winds when wind conditions near the surface were prohibitive. Thus, birds did not select flight altitudes only to optimize wind support. Rather, they preferred to fly at low altitudes unless wind conditions there were unsupportive of migration. Overall, flight altitudes of birds in relation to environmental conditions appear to reflect a balance between different adaptive pressures.  相似文献   

8.
Each month over a period of 22 months two groups of female rats were given i.p. 2.5 mg reserpine/kg BW and the number of gastric ulcers/rat were counted 24 h later. One group (n = 40) was kept for 17 days under environmentally controlled conditions (temperature, humidity, light intensity, length of photoperiod) while the other group (n = 40) was maintained for the same 17 days in a room near the open window under uncontrolled conditions. Under uncontrolled conditions gastric ulcer rate was negatively correlated with Ta (r=–0.87), Ta+Twb(r=–0.84), and Teq=Ta+2e (r=–0.83) of the last 24 hours. The correlation coefficients were higher with meteorological data of the 24 hours after administration of reserpine than with the data of the previous 16 days. No seasonal variation of ulcer morbidity was observed in the rats kept under controlled conditions. Hence, in rats, reserpine increases the gastric ulcer rate in the cold. Serious errors might arise in the interpretation of experiments when the rats are not housed under environmentally controlled conditions.  相似文献   

9.
The relationships between behaviour and synoptic-scale weather patterns and wind speeds for wandering (Diomedea exulans), black-browed (D. melanophrys) and light-mantled sooty (Phoebetria palpebrata) albatrosses were examined using observations collected from ships in the Southern Ocean south of Tasmania, Australia. Wandering albatrosses were found in high-pressure systems in significantly higher numbers than expected than in low-pressure systems. Wandering albatrosses were also found more frequently at lower latitudes than were black-browed and light-mantled sooty albatrosses. Light-mantled sooty and black-browed albatrosses showed no significant association with high- or low-pressure systems, suggesting that they can use either pressure system for travel. High-pressure systems may act as "traps" for wandering albatrosses, due to the lower wind speeds generally associated with these systems.  相似文献   

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The pattern of lion predation in Nairobi Park   总被引:1,自引:0,他引:1  
The feeding habits of lions in Nairobi National Park have been observed between 1968 and 1972. Nairobi Park is briefly described and the herbivore and predator populations are discussed. The relationship between the changing status of the prey population for the period 1968-72 and the feeding habits of the lions is examined and compared with data from earlier years. Selection ratio (preference ratio) for three of the most important prey species is more closely adjusted to the abundance of these species in the total ungulate population than was the case prior to 1968. Only warthog and eland form an exception. Predation on wildebeest shows the most marked decrease although this species has been increasing during the last 5 years. Wildebeest, kongoni, zebra and warthog have provided 80% of total kills throughout the study on the basis of numbers killed. On this basis, warthog has the highest preference rating. However, the largest contribution to the lions' diet expressed in kg is by kongoni, followed by zebra, wildebeest, eland and warthog, in that order. Kongoni and wildebeest contribute most during the first half of the year and zebra and eland during the last 6 months. Selection for males is significant in zebra and eland and highly significant in kongoni, whilst only in zebra is selection for juveniles evident.  相似文献   

12.
Herbivory has long been recognized as a significant driver of plant population dynamics, yet its effects along environmental gradients are unclear. Understanding how weather modulates plant–insect interactions can be particularly important for predicting the consequences of exotic insect invasions, and an explicit consideration of weather may help explain why the impact can vary greatly across space and time. We surveyed two native prickly pear cactus species (genus Opuntia) in the Florida panhandle, USA, and their specialist insect herbivores (the invasive South American cactus moth, Cactoblastis cactorum, and three native insect species) for five years across six sites. We used generalized linear mixed models to assess the impact of herbivory and weather on plant relative growth rate (RGR) and sexual reproduction, and we used Fisher's exact test to estimate the impact of herbivory on survival. Weather variables (precipitation and temperature) were consistently significant predictors of vital rate variation for both cactus species, in contrast to the limited and varied impacts of insect herbivory. Weather only significantly influenced the impact of herbivory on Opuntia humifusa fruit production. The relationships of RGR and fruit production with precipitation suggest that precipitation serves as a cue in determining the trade‐off in the allocation of resources to growth or fruit production. The presence of the native bug explained vital rate variation for both cactus species, whereas the invasive moth explained variation only for Ostricta. Despite the inconsistent effect of herbivory across vital rates and cactus species, almost half of Ostricta plants declined in size, and the invasive insect negatively affected RGR and fruit production. Given that fruit production was strongly size‐dependent, this suggests that Ostricta populations at the locations surveyed are transitioning to a size distribution of predominantly smaller sizes and with reduced sexual reproduction potential.  相似文献   

13.
1. Micro-crustacea of the genus Daphnia and Eudiaptomus have evolved different physiological mechanisms for coping with life in a rapidly changing environment. In this paper, we analyse some of the physical and biological factors influencing the winter abundance of the two species in a small lake (Esthwaite Water in Cumbria).
2. The results demonstrate that much of the year-to-year variation in their relative abundance can be related to long-term changes in the weather. The highest numbers of Daphnia were typically found in cold, calm winters when small flagellates were relatively abundant. In contrast, the highest numbers of Eudiaptomus were found in mild, windy winters when the phytoplankton community was dominated by colonial diatoms.
3. Year-to-year variations in the winter abundance of Eudiaptomus had no effect on their subsequent development but the numbers of overwintering Daphnia had a significant effect on the size of their first spring 'cohort'. The most important factor influencing the overwintering performance of the two species was the water temperature.
4. Winter air temperatures over much of Europe are influenced by the atmospheric pressure variation known as the North Atlantic Oscillation (NAO). Winter water temperatures in Esthwaite Water were strongly correlated with this empirical index and there was a significant positive correlation between the NAO and the number of overwintering Eudiaptomus.  相似文献   

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The influence of weather and egg contamination on the dynamics of herbage contamination with infective larave of Cooperia oncophora was investigated on artificially contaminated grass plots and in a grazing experiment with 24 first-year grazing calves from May to October 1987 in Lower Saxony, Germany. On the experimental plots the larval translation was highest at the beginning of July and in the second part of September, following high mean weekly temperatures. Between July and September peak recovery of larvae from herbage occurred 4 weeks after contamination. A seasonal pattern of larval translation similar to that on the experimental plots could be demonstrated on the grazed pastures when the number of larvae per m2 of pasture had been adjusted to the previous egg output by means of a contamination index. The resulting 'relative larval density' is regarded as a good indicator for larval development on pasture. From July to September the larval population on pasture resulted mainly from the egg contamination 2-3 weeks earlier. The short persistence of the infective larvae on herbage was probably due to the frequent and heavy rainfall throughout the season, causing a passive washout of larvae into the soil. On single pastures the larval density started to increase within 1 week after the calves had first contact with these fields. The impact of the calves on the distribution of larvae is discussed.  相似文献   

16.
Student bronchial asthma at the University of Minnesota was studied in grain sensitive and in control groups to find the influence of air pollutants from nearby grain installations on this problem.Under relatively high dust conditions it was observed that grain sensitive students had a two-fold increase in asthma attacks while the controls showed no significant changes. A combined association of wind direction and relatively high dust conditions with asthma gave a correlation of higher significance in the grain sensitive group. Multiple associations indicated that this relationship is only weakly affected by seasonal and temperature changes. It was also observed that relative humidity conditions may significantly influence the effectiveness of the dust exposure in sensitive students. Weather parameters showed no association with asthma in the control group.
Zusammenfassung Bronchialasthma bei Studenten der Universität Minnesota wurde bezüglich der Empfindlichkeit gegen Getreidesamen mit Kontrollgruppen untersucht, um den Einfluss der in der Luft befindlichen Pollen durch nahe gelegene Getreidefelder zu finden. Unter verhältnismässig hohen Konzentrationen wurde beobachtet,dass gegen Getreidesamen empfindliche Studenten doppelt so viele Asthmaanfälle hatten, wie die Kontrollgruppe, die keine signifikante Änderung zeigte. Eine Verbindung von Windrichtung und relativ hohen Staubkonzentrationen mit Asthmaanfällen ergab eine Korrelation von höherer Signifikanz in der sensiblen Gruppe. Weitere Zuordnungen zeigten, dass diese Beziehung nur wenig durch Änderungen von Jahreszeit und Temperatur beeinflusst wird. Es wurde auch beobachtet, dass die Relative Feuchte die Empfindlichkeit gegen Pollen bei entsprechend sensibilisierten Studenten beeinflussen kann. In der Kontrollgruppe zeigten Wetterparameter keine Beziehung zum Asthma.

Resume On a étudié les accès d'asthme bronchial provoqués par les polluants de l'atmosphère provenant d'entreprises travaillant les céréales et situées dans le voisinage du l'Université du Minnesota. Pour ce faire,on s'est servi d'étudiants de la dite Université sensibles aux poussières de céréales d'une part et d'un groupe de contrôle d'autre part. Dans des conditions de poussière relativement forte,on a observé que les étudiants sensibles aux poussières de céréales présentaient une fréquence double d'accès d'asthme alors que le groupe de contrôle n'était pas touché de façon significative. En utilisant une conbinaison des facteurs direction du vent et forte poussière d'une part, accès d'asthme d'autre part,on obtient une corrélation plus significative dans le groupe des gens sensibles.Des combinaisons multiples indiquent que cette corrélation n'est que peu influencée par la saison ou des changements de température. On a aussi remarqué que les conditions d'humidité relative peuvent influencer de façon significative la sensibilité effective aux poussières des étudiants du premier groupe. Quant au groupe de contrôle, on n'a pas trouvé de relation entre les accès d'asthme et les paramètres météorologiques.


Paper presented during the Fourth International Biometeorological Congress, New Brunswick, N.J., 26 August – 2 September 1966.This work was performed under Air Pollution Grant No. AP 00090-07,Division of Air Pollution, Bureau of State Services, United States Public Health Service.  相似文献   

17.
The seasonal incidence of the coffee berry moth, Prophantis smaragdina (Butler) (Lepidoptera: Pyralidae), was investigated on Coffea arabica L. in Jimma, Ethiopia. Our results showed that; the coffee berry moth was present throughout the study period except during November and December. The average incidence was 24.5% and the peak incidence (61%) was in September. Multiple correlation analysis was used to estimate the strength of association between weather variables and the incidence of the pest, and stepwise (both forward and backward) regression analysis was used to select the best explanatory variable. There were strong associations among the explanatory weather variables, indicating the potential problem of multicollinearity in the regression analysis. Relative humidity had a highly significant regression coefficient of 2.228 and was selected in the stepwise regression analysis as the best explanatory variable. The results of the study can be used in designing an integrated pest management strategy against the coffee berry moth.  相似文献   

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目的探索肺炎支原体(Mycoplasma pneumoniae,MP)抗体阳性对咳嗽变异性哮喘(cough variant asthmaCVA)患儿肺功能的影响。方法收集72例初次诊断CVA的患儿,根据血清MP抗体结果分为CVA合并MP抗体阳性(以下记CVA合并MP)组,CVA组。分别对两组进行支原体抗体及肺功能检测。结果纳入本研究的CVA患儿,MP抗体阳性占29%,且这部分患儿中女孩比男孩多。CVA患儿肺功能FVC、FEV1/FVC、PEF、MMEF75/25各项指标均下降(P〈0.05),合并MP组FVC、FEV1/FVC、PEF值变化差异无统计学意义(P〉0.05),而MMEF75/25下降差异有统计学意义(P〈0.05);CVA合并MP组支气管激发试验以极轻度、轻度为主(P〈0.05),而CVA组以中重度为主(P〈0.05);CVA合并MP组,在治疗一个月时FEV1%升高,差异有统计学意义(P〈0.05);治疗相同时间两组间FEV1%差异无统计学差异(P〉0.05)。结论呼吸道的多种微生物间形成复杂而又互相联系的群落,MP使气道黏膜受到损害,影响呼吸系统局部微生态,这与哮喘的形成有某种联系。MP抗体阳性的CVA患儿气道高反应性较低,相比之下,小气道阻塞加重,且其对CVA治疗过程中肺通气功能的变化没有影响。  相似文献   

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