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排序方式: 共有19条查询结果,搜索用时 140 毫秒
1.
通过南宁吴圩国际机场对机场飞行区4类生境中两栖爬行类的调杏,记录到3目11科22种.较为丰富的两栖爬行动物种类和数量成为机场鸟类重要的食物源之一,吸引了捕食性鸟类前来栖息和觅食.分析了解两栖爬行动物情况,对于全面了解亚热带和北热带地区的机场鸟类的食物源和活动规律具有十分重要的意义.并提出建议在今后对于鸟撞防治研究应当开展对两栖爬行类作为鸟类食物源这方面的调查研究工作.  相似文献   
2.
重庆机场草地土壤动物群落特征及其与鸟类关系的初步研究   总被引:14,自引:0,他引:14  
对重庆机场草地土壤动物群落的组成,结构和时空动态特征进行了比较研究,初步分析了土壤动物与机场鸟类在种类和数量上的动态关系。结果表明:土壤动物的优势类群为蜱螨目;常见类群多为大,中型土壤动物,是鸟类捕食的主要对象;活动性弱的小型土壤动物是幼虫主要分布在土壤和腐质层中,且群落的多样性和稳定性较高;  相似文献   
3.
To determine whether chronic exposure to airport noise affects children, a study was conducted of the physical growth of children, aged 5-13 years, from two communities, one exposed to airport noise (n = 148) and another, not exposed (n = 102). Ten standard anthropometric measurements were made according to U.S. Health Examination Survey guidelines, and information on the social and biological characteristics of each family was collected in interviews. Hotelling's T2-tests were performed comparing the noise-exposed and nonnoise-exposed samples. There was no significant difference between the sample for measurements of social and biological characteristics of the families (including socioeconomic status and maternal reproductive history). Parental anthropometrics differed significantly (T2 = 24.32, P = 0.0001) as did child anthropometrics (T2 = 21.01, P = 0.032). For the child anthropometrics, noise-exposed children's slightly smaller measures of body bulk, together with their larger facial breadths, contributed to the significant T2. When the entire sample (n = 250) was analyzed by multiple linear regression, noise exposure was a significant predictor only of male triceps and subscapular skinfolds. For these two variables, and most other anthropometrics, however, the beta coefficients were negative for both sexes. In order to include information on the covariance structure among all variables, a canonical correlation analysis was performed. Noise exposure loaded negatively on the third canonical variate and was paired with positively loaded measures of body bulk. Taken together, the three analyses suggest that while there is some evidence for a slight effect of airport noise on measures of body bulk for males in this sample, most measures of postnatal growth for both males and females were unaffected by the noise levels experienced.  相似文献   
4.
Three different biomarkers: sister-chromatid exchanges (SCE), micronuclei (MN), and the Comet assay, were used to evaluate different kinds of genetic damage in peripheral blood lymphocytes from 34 male workers at Barcelona airport, exposed to low levels of hydrocarbons and jet fuel derivatives. The control group consisted of 11 unexposed men. We also investigated the ras p21 protein levels in plasma, in order to evaluate whether the ras gene could serve as a suitable potential marker of carcinogenic pollution in occupationally exposed cohorts. SCE and MN analyses failed to detect any statistically significant increase in the airport workers when compared with the controls, and in fact, the frequency of binucleated cells with MN in the exposed group was significantly lower than that obtained in the control. However, slight but significant differences in the mean comet length and genetic damage index were observed between the exposed and control groups when using the Comet assay. There were no statistically significant differences between both groups in p21 plasma levels. Smoking was shown to affect significantly both SCE and high frequency cells (HFC) in the exposed group.  相似文献   
5.
众多疫病病毒来源于野生动物,具有向人类传播的风险,尤其是具有飞翔能力的鸟类不易控制,所携带的病毒传播广泛,威胁人畜安全。因此,充分了解鸟类携带疫病情况以及鸟类迁徙路线中重点区域的疫病风险,对疫病防控非常重要。本文总结了鸟类主要携带的病原类型,如冠状病毒、流感病毒、寄生虫和新城疫病毒等。着重探讨鸟类携带病原对生物安全防范重点区域的人员和动物的疫病风险,包括自然保护区、机场和禽类养殖场等,并从加强候鸟迁徙的动态监测、加强栖息地检疫和保护、家禽定期疫苗接种等方面提出疫病防范措施。  相似文献   
6.
Airport detection in remote sensing images: a method based on saliency map   总被引:1,自引:0,他引:1  
The detection of airport attracts lots of attention and becomes a hot topic recently because of its applications and importance in military and civil aviation fields. However, the complicated background around airports brings much difficulty into the detection. This paper presents a new method for airport detection in remote sensing images. Distinct from other methods which analyze images pixel by pixel, we introduce visual attention mechanism into detection of airport and improve the efficiency of detection greatly. Firstly, Hough transform is used to judge whether an airport exists in an image. Then an improved graph-based visual saliency model is applied to compute the saliency map and extract regions of interest (ROIs). The airport target is finally detected according to the scale-invariant feature transform features which are extracted from each ROI and classified by hierarchical discriminant regression tree. Experimental results show that the proposed method is faster and more accurate than existing methods, and has lower false alarm rate and better anti-noise performance simultaneously.  相似文献   
7.
Anthropogenic noise is of increasing concern to biologists and medical scientists. Its detrimental effects on human health have been well studied, with the high noise levels from air traffic being of particular concern. However, less is known about the effects of airport noise pollution on signal masking in wild animals. Here, we report a relationship between aircraft noise and two major features of the singing behavior of birds. We found that five of ten songbird species began singing significantly earlier in the morning in the vicinity of a major European airport than their conspecifics at a quieter control site. As birds at both sites started singing before the onset of air traffic in the morning, this suggests that the birds in the vicinity of the airport advanced their activity to gain more time for unimpaired singing before the massive plane noise set in. In addition, we found that during the day, chaffinches avoided singing during airplane takeoffs, but only when the noise exceeded a certain threshold, further suggesting that the massive noise caused by the airport can impair acoustic communication in birds. Overall, our study indicates that birds may be adjusting their mating signals and time budgets in response to aircraft noise.  相似文献   
8.
长沙黄花国际机场鸟类群落物种多样性分析   总被引:12,自引:1,他引:12  
为了获得长沙黄花国际机场鸟击防范工作所需的鸟类基础性资料,从2005年9月~2006年8月,通过对机场地区5种生境类型鸟类群落的调查与监测,记录到鸟类112种,属16目32科。其中46种属东洋界种类、45种属古北界种类、21种属广布种;留鸟46种、夏候鸟25种、冬候鸟29种、旅鸟12种。经RB频率指数测算,鸟类群落的优势种为白头鹎(Pycnonotus sinensis)、乌鸫(Turdus merula)和树麻雀(Passer montanus)。按鸟类生境分布系数划分,广布型的鸟类有44种,是该区鸟类群落组成的主体。鸟类群落的Shannon-Weiner物种多样性指数为1.607,均匀性指数为0.784。  相似文献   
9.
煤气炮和声波驱鸟器有效距离的评估   总被引:1,自引:0,他引:1  
鸟击事故主要发生在机场区域,通过使用驱鸟设备减少机场鸟类活动是预防鸟击的主要措施之一。本研究以家鸽和红隼两种高危险鸟类作为受试对象,选择沈阳桃仙国际机场使用的煤气炮和定向声波驱鸟器,观察在设备正常运行期间鸟类位于不同距离上的行为反应,探究两种驱鸟设备的有效作用距离以及效果。结果表明: 家鸽和红隼在距离煤气炮驱鸟器10、30 m时的警戒、逃跑行为显著高于对照,而在50 m处的各种行为次数与对照没有显著差别。家鸽和红隼在距离定向声波驱鸟器50、100 m时能够显著引起警戒和逃跑行为,在300 m处仍能显著引起红隼的警戒行为。可见,煤气炮的有效驱鸟距离为30 m,定向声波的有效驱鸟距离可达300 m,即定向声波的驱鸟效果要强于煤气炮。本研究可为机场引进驱鸟设备以及合理使用提供依据。  相似文献   
10.
四川南充高坪机场秋冬季节鸟类多样性与鸟撞预防   总被引:2,自引:0,他引:2  
2006年9月-2007年2月,对四川南充高坪机场及其周围4种生境(草地、农耕区、村囤、松林)的鸟类进行调查,并进行鸟类多样性指数分析.结果共记录到鸟类81种,隶属于13目37科;秋冬季农耕区和村囤的鸟类密度、数量明显比草地和松林高;机场草地冬季鸟类的密度明显比秋季高.结合鸟类的生活习性及其栖息生境、Ⅳ值、分布广度和在各生境中的优势密度和总范围里的密度,秋季对鸟撞最具危险的是白鹭、家鸽、山斑鸠、白鹡鸰、白头鹎、小云雀、小鹀等;冬季对鸟撞最具威胁的是家鸽、小云雀、小鹀、金翅雀、白头鹎、水鹨等.并相应提出了相应一些的预防措施,如减少结实的植物、剪草降低草高、控制土壤动物的密度等.  相似文献   
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