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1.
阐明水鸟栖息地利用与环境因子的关系有助于制定针对性的水鸟保护对策。本研究在2012~2013年冬季对崇明东滩鸟类栖息地优化区内越冬水鸟的种类、数量以及6种环境因子(植被面积比例、裸地面积比例、水深、地形变异、栖息地结构多样性和干扰)进行调查,以了解水鸟对人工湿地的栖息地利用及其影响因子。野外调查共记录到水鸟24种9 018只,其中优势种为斑嘴鸭(Anas poecilorhyncha)和绿头鸭(A.platyrhynchos);栖息地优化区内水鸟休息的个体数量占总数量的79.2%,这表明优化区是大多数水鸟的休息地,而小(Tachybaptus ruficollis)、白骨顶(Fulica atra)、黑水鸡(Gallinula chloropus)、白琵鹭(Platalea leucorodia)和黑脸琵鹭(P.minor)的觅食个体数量超过60%,说明优化区也为这些鸟类提供了觅食地。逐步回归分析表明,裸地面积比例是影响越冬水鸟种类分布的最主要因子;尽管游禽在地形变异较大、植被面积比例较低的区域数量较多,但在休息时游禽更偏好于裸地面积比例较高的区域,而涉禽休息时偏好于地形变异较大的区域。为增加栖息地优化区内的水鸟多样性,建议在优化区内种植水鸟可食的沉水植物以增加水鸟的食物资源,同时增加裸地面积比例和地形变异程度,更好地为水鸟提供栖息地。  相似文献   

2.
Robert Spencer 《Bird Study》2013,60(3):177-190
Since 1955 there have been striking extensions of the area from which Blackbirds ringed in Britain are recovered, involving Finland in summer and France and Iberia in winter. The author suggests that these changes, though due in part to increased ringing, also provide evidence that the Blackbird is still expanding its range in northern Europe.  相似文献   

3.
云南纳帕海黑颈鹤越冬行为与生境利用初步观察   总被引:2,自引:0,他引:2  
2005年10月~2006年3月在纳帕海自然保护区对黑颈鹤越冬期行为和生境利用进行了30天观察.采用扫描取样和目标取样对黑颈鹤的行为和生境利用进行了观察.将行为划分为觅食、喂食与索食、伫立、休息、运动、保养、社群等7种.整个越冬期黑颈鹤的主要行为是觅食,觅食行为在越冬中、末期在所有行为所占比例逐渐增加.黑颈鹤的觅食行为60%以上发生在沼泽,其次是沼泽畔的草地.因此,保护好湿地沼泽对黑颈鹤在纳帕海顺利越冬极为重要.  相似文献   

4.
青头潜鸭(Aythya baeri)是世界极危级(CR)物种,2018年至今在河南民权黄河故道国家湿地公园均调查到稳定的青头潜鸭越冬种群。研究青头潜鸭对不同栖息地的利用方式及所受干扰有利于该物种的保护管理。本研究分析了越冬期不同栖息地及不同性别青头潜鸭的行为时间分配差异,以及人为干扰对青头潜鸭活动的影响。2020年12月采用焦点取样法对河南民权黄河故道国家湿地公园内青头潜鸭进行行为观察,按照青头潜鸭对栖息地的利用率,将其栖息地类型分为池塘、大水面荷塘和开阔水域。使用单因素方差分析(ANOVA)及t检验比较不同栖息地及性别间差异的显著性。青头潜鸭的主要行为是休息(44.4%)和觅食(34.2%),且在不同栖息地存在显著差异。池塘中的觅食行为占比(50.1%)显著高于大水面荷塘和开阔水域;大水面荷塘中的休息行为占比(63.1%)显著高于池塘和开阔水域。雌雄之间存在一定的行为差异,雌性觅食时间高于雄性,整理行为时间低于雄性,这种差异受栖息地的影响。三种类型栖息地均存在不同程度的人为干扰,池塘中所受干扰程度最高,主要干扰源为钓鱼、行人和施工,荷塘和开阔水域主要干扰为打渔船。本研究表明,对于越冬期的青头潜鸭,池塘是重要觅食地,荷塘可作为躲避干扰的休息场所,开阔水域可作为稳定的觅食栖息场所。对青头潜鸭的保护应考虑到不同栖息地的生态作用,以及青头潜鸭对不同干扰的容忍度,采取相应措施开展保护行动。  相似文献   

5.
福建省兴化湾滨海养殖塘冬季水鸟的栖息地利用   总被引:3,自引:3,他引:3  
20D7年12月至2008年3月对福建省兴化湾东北部江镜华侨农场(25°29′~25°33′N,119°23′~119°26′E)滨海养殖塘水鸟的栖息地利用进行了研究.选取了6个养殖塘作为样地,总面积360 hm2,共记录到水鸟6目8科25种.潮汐变化是影响养殖塘内越冬水鸟栖息的重要因素.高、中、低3种不同潮位下养殖塘水鸟群落特征差异较大.水鸟的种数和数量随潮水的涨高而显著增加,优势种则减少;多样性指数和均匀性指数随潮水的涨高而降低,优势度则增大.养殖塘的水深是影响水鸟栖息的另一个重要因素.4个不同水深区域水鸟群落的种类组成及密度差异显著,鸻鹬类、鸥类、鹭类等鸟类在中等水位区和浅水区栖息,鸭类主要栖息在深水区,而无水区仅有少数鹭类活动.在潮汛期间,滨海养殖塘是水鸟良好的临时栖息地,科学管理可使养殖塘人工湿地与潮间带滩涂共同满足越冬水鸟的栖息需求.  相似文献   

6.
For nearly 70?years, studies have shown large sex differences in human mate selection preferences. However, most of the studies were restricted to a limited set of mate selection criteria and to college students, and neglecting relationship status. In this study, 21,245 heterosexual participants between 18 and 65?years of age (mean age 41) who at the time were not involved in a close relationship rated the importance of 82 mate selection criteria adapted from previous studies, reported age ranges for the oldest and youngest partner that they would find acceptable, and responded to 10 yes/no questions about a potential marriage partner. For nearly all mate selection criteria, women were found to be the more demanding sex, although men placed consistently more value on the physical attractiveness of a potential partner than women. Also, the effects of the participants?? age and level of education were nearly negligible. These results demonstrate the robustness of sex differences in mate selection criteria across a substantial age range.  相似文献   

7.
鄱阳湖保护区白琵鹭越冬种群分布   总被引:2,自引:0,他引:2  
2007年10月至2010年3月3个冬季的调查显示,鄱阳湖国家级自然保护区白琵鹭(Platakakucorodia)种群数量在12月或1月达到峰值,3个越冬期最大种群数量分别为4 757只、10 385只和7 268只.大湖池、沙湖、常湖池是白琵鹭主要的栖息地,每个越冬期在这3个湖泊栖息的白琵鹭种群数量占保护区总数量的...  相似文献   

8.
2008年11月至2009年3月,采用样线法、样方法和因子分析法对鄱阳湖国家级自然保护区越冬白鹤(Grus leucogranus)觅食地特征进行了研究。结果表明,白鹤在保护区的分布具有时空动态性,主要受水位和食物的控制;白鹤对不同类型觅食地具有选择性(P0.05),对沉水植物型觅食地,即以苦草(Vallisneria natans)、黑藻(Hydrilla verticillata)、马来眼子菜(Potamogeton malaianus)为主的沉水植物型生境利用度最大;白鹤各型觅食地各因子的方差分析表明,植被因子具有极显著差异(P0.001),基底因子和掘食因子具有显著差异(P0.05);因子分析表明,觅食地选择以取食效率因子为主,其次是基底因子和食物丰富度因子。  相似文献   

9.
In the present study an extensive amount of data, comprising more than 30,000 offspring in total, was analyzed to evaluate the influence of age and sex on the recombination frequency in the K-PGD segment of the equine linkage group (LG) I and the influence of age, breed and sex on recombination in the Al-Es segment of LG II. A highly significant sex difference is reported for both segments. Male and female recombination values in the K-PGD segment were estimated at 25.8 ± 0.8 and 33.3 ± 2.5%, respectively. Similarly, recombination was less frequent in the male (36.6 ± 0.7%) than in the female (46.6 ± 1.2%) in the Al-Es segment. Comparison of data from two Swedish horse breeds revealed no significant breed differences in either sex for recombination in the Al-Es segment. No evidence of an age effect was found in any segment or sex. The distribution of individual male recombination estimates was also investigated, and a significant heterogeneity among stallions was revealed in the K-PGD segment. The results are discussed in relation to previous studies on factors affecting recombination in mammals.  相似文献   

10.
《Endocrine practice》2010,16(1):71-79
ObjectiveTo examine the performance of weightbased formulae for estimating the levothyroxine dosage requirement in athyreotic patients and to determine whether formula performance is affected by age, sex, or menstrual status.MethodsIn this prospective study, euthyroid study participants aged 18 to 65 years were followed up after total thyroidectomy at 4 time points: 6-8 weeks, 12-16 weeks, 6 months, and 1 year. Patient weight, serum thyrotropin concentration, and levothyroxine dosage required were recorded at each time point. The postoperative starting levothyroxine dosage was 1.7 mcg/kg daily for patients with benign thyroid disease and 2.2 mcg/kg daily for patients with thyroid cancer. Actual body weight was used to calculate the initial dosage. At steady state, adjustments were made in each patient’s levothyroxine dosage until the target thyrotropin concentration was reached. The levothyroxine dosage required to achieve this goal was documented.ResultsFifty patients were included (37 women, 13 men). Formulae based on actual body weight were accurate in achieving a normal thyrotropin concentration in 48% to 75% of participants. Final dosages to achieve normal thyrotropin values were similar in men (1.43 mcg/kg daily) and menopausal women (1.68 mcg/kg daily), but higher in premenopausal women (2.10 mcg/kg daily). When a formula based on ideal body weight was used, the requirement for menopausal women (2.34 mcg/kg daily) was similar to that of premenopausal women (2.44 mcg/kg daily), but the requirement for men (1.73 mcg/kg daily) remained lower than that observed in both female groups.ConclusionsWhen actual body weight was used to calculate levothyroxine dosage requirement, premenopausal women appeared to have a greater requirement than either menopausal women or men. When ideal weight was used, the requirement of all women was greater than that of men. Perhaps with formulae using actual weight, this apparent sex difference is masked by the greater weight, older age, or altered hormonal milieu of menopausal women. (Endocr Pract. 2010;16:71-79)  相似文献   

11.
This is the first study to examine how both structural and functional components of individuals’ social networks may moderate the association between biological sex and experimental pain sensitivity. One hundred and fifty-two healthy adults (mean age = 22yrs., 53% males) were measured for cold pressor task (CPT) pain sensitivity (i.e., intensity ratings) and core aspects of social networks (e.g., proportion of friends vs. family, affection, affirmation, and aid). Results showed consistent sex differences in how social network structures and intimate relationship functioning modulated pain sensitivity. Females showed higher pain sensitivity when their social networks consisted of a higher proportion of intimate types of relationship partners (e.g., kin vs. non kin), when they had known their network partners for a longer period of time, and when they reported higher levels of logistical support from their significant other (e.g., romantic partner). Conversely, males showed distinct patterns in the opposite direction, including an association between higher levels of logistical support from one’s significant other and lower CPT pain intensity. These findings show for the first time that the direction of sex differences in exogenous pain sensitivity is likely dependent on fundamental components of the individual’s social environment. The utility of a social-signaling perspective of pain behaviors for examining, comparing, and interpreting individual and group differences in experimental and clinical pain reports is discussed.  相似文献   

12.
崇明东滩是亚太地区候鸟迁徙路线的重要中转站,也是上海地区促淤圈围的重点区域。水稻(Oryza sativa)田作为当地分布广泛且重点改造的人工湿地,研究其是否具有水鸟招引效果具有重要意义。本研究于2013和2014年冬季采用样方法对崇明东滩两种不同管理模式的水稻田,即2013年开始改造的传统模式水稻田和改造多年的机械化模式水稻田,进行了水鸟群落及生境因子调查,以探究不同管理模式下水稻田内生境差异,水鸟对不同生境的利用程度及其不同生境中的关键因子对水鸟分布的影响。调查期间共记录到水鸟5目7科18种1 795只次,其中传统模式水稻田记录到水鸟5目6科17种1 756只次,优势种为绿翅鸭(Anas crecca)、斑嘴鸭(A.poecilorhyncha)、鹤鹬(Tringa erythropus);机械化模式水稻田录到水鸟4目5科6种39只次,优势种为小??(Tachybaptus ruficollis)和凤头麦鸡(Vanellus vanellus)。T检验结果显示,传统模式水稻田对水鸟的招引效果(即多度和物种丰富度)显著优于机械化模式水稻田,2014年改造后传统模式水稻田的水鸟招引效果显著优于2013改造初期。多元回归分析显示,明水面面积比例是影响水稻田水鸟种类、数量分布的最重要因子。结果表明,明水面面积和适合的水位高度是影响冬季水稻田水鸟招引效果的主要因素,为提高冬季水稻田水鸟保育效果,应注重营造、维护冬季水稻田中水文条件。  相似文献   

13.
14.
Abstract: San Joaquin kit foxes (Vulpes macrotis mutica) are an endangered species with a narrow geographic range whose natural populations are limited by predation by coyotes (Canis latrans). In the warm, arid grassland and shrubland habitats where kit foxes occur, coyotes are more cover dependent than kit foxes, creating the possibility of habitat segregation. Effects of habitat variation on coyote and kit fox competition are unknown. We assessed exploitation and interference competition between coyotes and kit foxes in grassland and shrubland habitats to determine if such competition varies among habitats. With respect to exploitation competition, we evaluated habitat and spatial partitioning, diet, prey abundance, and survival for kit foxes and coyotes at the Lokern Natural Area in central California, USA, from January 2003 through June 2004. Kit foxes partitioned habitat, space, and diet with coyotes. Coyotes primarily used shrubland habitats whereas kit foxes selectively used burned grasslands. Kit foxes and coyotes had high dietary overlap with regards to items used, but proportional use of items differed between the 2 species. Kit foxes selected for Heermann's kangaroo rats (Dipodomys heermanni), which were closely tied to shrub habitats. With respect to interference competition, predation was the primary source of mortality for kit foxes, and survival of individual kit foxes was inversely related to proportion of shrub habitat within their home ranges. Our results suggest that a heterogeneous landscape may benefit kit foxes by providing habitat patches where predation risk may be lower.  相似文献   

15.
中华秋沙鸭在中国的近期越冬分布与数量   总被引:8,自引:3,他引:8  
中华秋沙鸭(Mergus squamatus)以往在我国广有越冬记录,但分布点零散,且多为小群或零星个体,很少在同一地点见到10只以上的个体记录。20世纪90年代以来在个别地点虽发现有中华秋沙鸭的越冬群体,但缺少持续性观察结果。21世纪初在赣东北的弋阳、婺源相继发现中华秋沙鸭的较大越冬群,总数量至少超过100只,且数量和分布地点相对保持稳定。两地记录到的最大数量分别超过该种全球总量的1%,应当加强保护。  相似文献   

16.
Obesity and ageing are emerging issues in the management of captive primates, including Chimpanzees, Pan troglodytes. Studies on humans show that obesity and old age can independently increase the risk of inflammatory-associated diseases indicated by elevated levels of pro-inflammatory cells and proteins in the blood of older or obese compared to levels in younger or non-obese individuals. In humans, sex can influence the outcomes of these risks. Health management of these problems in chimpanzee populations requires an understanding of similarities and differences of factors influencing inflammatory disease risks in humans and in chimpanzees. We examined the relationship between age, sex and Body Mass Index (BMI) with hematological biomarkers of inflammatory disease risk established for humans which include the neutrophil to lymphocyte ratio (NLR), and neutrophil, white blood cell (WBC), platelet microparticle and platelet counts. We found that higher values of NLR, neutrophil count and platelet microparticle count were associated with higher BMI values and older age indicating increased inflammation risk in these groups; a similar pattern to humans. There was a strong sex by age interaction on inflammation risk, with older males more at risk than older females. In contrast to human studies, total WBC count was not influenced by BMI, but like humans, WBC and platelet counts were lower in older individuals compared to younger individuals. Our findings are similar to those of humans and suggest that further insight on managing chimpanzees can be gained from extensive studies of ageing and obesity in humans. We suggest that managing BMI should be an integral part of health management in captive chimpanzee populations in order to partially reduce the risk of diseases associated with inflammation. These results also highlight parallels in inflammation risk between humans and chimpanzees and have implications for understanding the evolution of inflammation related diseases in apes.  相似文献   

17.
18.
四川山鹧鸪的分布及生境选择   总被引:4,自引:0,他引:4  
研究了四川山鹧鸪(Arborophila rufipectus)的分布区域和栖息地的生境,认为四川山鹧鸪的分布范围比已知的要大,但其实际分布区呈明显的岛屿状,显示出生境的破碎化;指出四川山鹧鸪的适宜生境是原始的常绿阔叶林、针阔混交林和具有较大常绿落叶阔叶乔木树种盖度的多年生次生林,亦可选择部分人工林,而对地表灌丛密度大的次生幼林以及人工幼林生境不喜好。由于天然林的禁伐和生态林的管护,四川山鹧鸪的栖息地趋于稳定并有所扩大。但四川山鹧鸪仍然处于濒危状态。  相似文献   

19.
The coastal waters off the southeastern United States (SEUS) are a primary wintering ground for the endangered North Atlantic right whale (Eubalaena glacialis), used by calving females along with other adult and juvenile whales. Management actions implemented in this area for the recovery of the right whale population rely on accurate habitat characterization and the ability to predict whale distribution over time. We developed a temporally dynamic habitat model to predict wintering right whale distribution in the SEUS using a generalized additive model framework and aerial survey data from 2003/2004 through 2012/2013. We built upon previous habitat models for right whales in the SEUS and include data from new aerial surveys that extend the spatial coverage of the analysis, particularly in the northern portion of this wintering ground. We summarized whale sightings, survey effort corrected for probability of whale detection, and environmental data at a semimonthly resolution. Consistent with previous studies, sea surface temperature (SST), water depth, and survey year were significant predictors of right whale relative abundance. Additionally, distance to shore, distance to the 22°C SST isotherm, and an interaction between time of year and latitude (to account for the latitudinal migration of whales) were also selected in the analysis presented here. Predictions from the model revealed that the location of preferred habitat differs within and between years in correspondence with variation in environmental conditions. Although cow-calf pairs were rarely sighted in the company of other whales, there was minimal evidence that the preferred habitat of cow-calf pairs was different than that of whale groups without calves at the scale of this study. The results of this updated habitat model can be used to inform management decisions for a migratory species in a dynamic oceanic environment.  相似文献   

20.

Aims

To measure the degree and direction of errors in recall of age at first sex.

Method

Participants were initially recruited in 1994–1995 (Wave I) with 3 subsequent follow-ups in: 1996 (Wave II); 2001– 2002 (Wave III); and 2007–2008 (Wave IV). Participants'' individual errors in recall of their age at first sex at Wave IV were estimated by the paired difference between responses given for age at first sex in Wave I and Wave IV (recalled age at first sex obtained at Wave IV minus the age at first sex obtained at Wave I).

Results

The mean of the recall-estimation of age at first sex at Wave IV was found to be slightly increased comparing to the age at first sex at Wave I (less than 1 year). The errors in the recalled age at first sex tended to increase in participants who had their first sex younger or older than the average, and the recalled age at first sex tended to bias towards the mean (i.e. participants who had first sex younger than the average were more likely to recall an age at first sex that was older than the age, and vice versa).

Conclusions

In this U.S. population-based sample, the average recall error for age at first sex was small. However, the accuracy of recalled information varied significantly among subgroup populations.  相似文献   

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