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181.
环境因素对丹顶鹤越冬行为的影响 总被引:3,自引:0,他引:3
丹顶鹤在盐城越冬期间各种环境因素对其行为都将产生一定的影响,对此我们进行了观察记录。该项工作主要用8×40、10×50双筒和20倍单筒望远镜实地观察、照相机摄影等直接记录丹顶鹤的各种行为;种群数量计算为直接计数法;气候因子则根据各级气象部门的预报结果,结合观察点温度计等手段测算。结果表明丹顶鹤越冬期间,气候因子的变化是对其行为产生直接影响的主要因素,温度、雨、雾、雪、风等发生大幅度变化时,都将导致越冬期丹顶鹤的行为发生相应的适应性变化,对迁徙行为的影响则更为明显。而食物和水源则通过气候因子的变化和安全度的影响再次反应到丹顶鹤的越冬行为中来。本文最后提出了减轻灾害性天气对丹顶鹤越冬行为的影响建议。 相似文献
182.
183.
We examined whether recreational tree climbing (TC) activities would have positive social impacts and rejuvenate an outdoor activity center and surrounding community forest in central Japan. Our case study comprised 3800 adults and children participating in TC activities at the Jyokoji Outdoor Activity Center (JOAC) in Seto, Japan. We focused on 1393 adult participants whom we considered to be the decision makers regarding family recreation, and we explored both the social impacts of TC and various factors that contributed to and distracted from the overall experience. Qualitative and quantitative data indicated that elements such as age, gender, tree preferences, tree appreciation, tree education, and technical instruction influenced the enjoyment of recreational TC and the positive effects on tree climbers. Overall, the climbing program had positive social impacts for the community forest and contributed to local conservation initiatives. Our case study suggests that other areas can benefit from incorporating TC programs into community forest planning to complement aesthetic, ecological, and restoration benefits and provide a new venue for recreation and conservation awareness. 相似文献
184.
卷叶螟绒茧蜂Apanteles derogatae Watanabe是棉大卷叶螟Sylepta derogata Fabricius幼虫期的一种重要内寄生蜂,对棉大卷叶螟种群有较好的控制作用。在实验室条件下,运用人工接虫观察法研究卷叶螟绒茧蜂对棉大卷叶螟幼虫的寄生行为。结果表明,该蜂搜寻寄主的时间平均为2.38 min,处理寄主的时间仅需0.86 min;寄生寄主的最适龄期为寄主2龄幼虫;对1龄幼虫的致死率达32%,但其寄生率仅为16%,其余16%的个体为穿刺致死。饲喂蜂蜜水能显著增加该蜂的产卵量,延长其产卵历期和增强其穿刺能力。寄生蜂的寄生能力与寄主密度的关系呈抛物线型:在寄生蜂均为16头/m~3雌蜂条件下,当寄主密度从80头/m~3增加到320头/m~3时,寄主的被寄生个体数随之增加,但当寄主密度超过320头/m~3后,寄主的被寄生个体数反而随寄主密度的上升呈下降趋势。 相似文献
185.
Differences in the behavior of the crossbred steers of different sire lines of Japanese Black cattle
Katsuji UETAKE Toshie ISHIWATA Robert J. KILGOUR Toshio TANAKA 《Animal Science Journal》2012,83(2):184-186
We determined differences in the behavior of the progeny of two major sire lines of Japanese Black cattle by recording the behavior of 35 and 70 half-sib steers of sires from fast (FG) and slow (SG) growing lines, respectively. Two sire lines of steers were mixed and allocated to nine pens with 11–12 animals per pen. The proportion of steers lying was significantly (P < 0.001) higher in the SG line (43.4 ± 5.7% compared to 40.3 ± 6.0%). The proportion of time spent eating concentrate feed (FG: 12.1 ± 2.3%; SG: 11.4 ± 2.1%), drinking (FG: 0.8 ± 1.1%; SG: 0.4 ± 0.6%), licking the feed trough (FG: 0.4 ± 0.6%; SG: 0.2 ± 0.4%) and performing tongue-playing (FG: 3.1 ± 4.6%; SG: 1.0 ± 1.9%) was significantly higher in FG, whereas the proportion of time spent resting (FG: 41.5 ± 12.8%; SG: 43.7 ± 10.9%) and performing self-licking (FG: 1.7 ± 1.4%; SG: 2.1 ± 1.3%) was higher in SG (all P < 0.05). These results show progeny of the FG sire engaged in more active behaviors compared to the progeny of the SG sire line. 相似文献
186.
管道工程环境与力学行为 总被引:1,自引:0,他引:1
长输管道所处的环境比较复杂,主要包括所输送介质的环境,运行操作环境、管道周边环境、沿线自然环境与灾害环境以及管道的施工制造环境。在这些环境的作用下,管道将产生相应的力学行为,主要有承载行为,变形行为,断裂行为,疲劳行为和腐蚀行为,为保证管道工程的经济合理性,使管道长期平稳运行,就要在设计阶段将管道所处环境与相应产生的力学行为有机地结合起来,从这一角度出发,提出合理选择线路,正确选用选材,腐蚀控制、管道保护、施工控制和管理维护等6项措施。 相似文献
187.
《中国林业科技(英文版)》2009,(2)
After freezing snow disaster,stands of Pinus massoniana,Cunninghamia lanceolata. Liquidambar formosana,Cinnamomum camphora and Phyllostachys pubescens and new burned areas in Hunan Province were surveyed by setting field plots.Moisture content and fuel load were measured by sampling and fire behavior(such as rate of fire spread) was calculated.The results showed that fuel load got doubled instantly,fuel thickness enhanced,fuel continuity swelled and water content of fuel decreased as shrubs and herbs die... 相似文献
188.
孙江明 《金陵科技学院学报》1999,(4)
收入分配差距是伴随经济增长出现的一种社会经济现象,它对经济增长本身又会产生一定的影响。近年来我国城镇居民收入水平保持较快的增长速度,社会物价水平稳中有降,但消费需求不旺,市场疲软的迹象已十分明显。究其原因,除了供求存在结构性矛盾造成有效供给不足,住房、教育、医疗保险制度的改革使居民预期购买压力增大,以及落后的消费观念和消费信贷体制外,居民收入分配差距扩大,城市低收入和贫困人口的增加已成为对消费需求产生消极影响的一个重要因素。因此,政府在积极增加投资支出、调整经济结构和发展消费信贷的同时,切不可忽视改善收入分配状况,以最终实现刺激消费、促进经济增长的目标。 相似文献
189.
In the marine environment, pelagic dispersal is important for determining the distribution and abundance of populations, as well as providing connections among populations. Estimates of larval dispersal from spawning grounds are important to determining temporal and spatial patterns in recruitment that may have significant influences on the dynamics of the population. We present a case study of the dispersal of Centropristis striata (black sea bass) larvae on the southeast U.S. continental shelf. We use a coupled larval behavior – 3D circulation model to compare the effects of the timing and location of spawning against that of larval vertical migration on larval dispersal. Using the results of field data on larval vertical distributions, we compare the dispersal of virtual 'larvae' which have ontogenetic changes in vertical behavior with that of particles fixed near the surface and near the bottom. Larvae were released at potential spawning sites four times throughout the spawning season (February through May) for 3 yr (2002–04) and tracked for the assumed larval duration (from 27 to 37 days including the egg stage). Results indicate that adult behavior, in the form of spawning time and location, may be more important than larval vertical behavior in determining larval dispersal on the inner- and mid- continental shelves of this region. 相似文献
190.
公务员是国家公务的执行者,依法行使行政权力。在改革开放和建设有中国特色社会主义的伟大实践中,我国公务员队伍的主流是好的,有着良好的社会主义道德风尚。但是由于种种复杂的原因,导致一些公务员行政道德有一定程度滑坡,行政道德行为失范现象屡见不鲜,甚至出现腐败现象。因此,加强对我国公务员行政道德行为的规制,进一步完善我国公务员制度,意义重大。 相似文献