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排序方式: 共有149条查询结果,搜索用时 15 毫秒
1.
红火蚁Solenopsis invicta是典型的社会性昆虫, 在防控过程中容易引起红火蚁巢体迁移和弃尸等现象, 影响防控效果。本研究对标记好的蚁巢施用茚虫威饵剂, 然后定时观察新增加的蚁巢数量和工蚁弃尸量。结果表明, 施用0.08%和0.1%茚虫威饵剂后, 所有处理均有新蚁巢出现, 施药后5~10 d, 新蚁巢大量出现, 随后蚁群趋向稳定, 新增蚁巢减少, 至处理后25~30 d, 再次出现新蚁巢。0.1%茚虫威饵剂15 g/巢处理在施药后5 d出现8个新蚁巢, 药后10 d和30 d分别又新增5个蚁巢, 其他时间新增蚁巢数较少。按处理剂量, 药后30 d, 2种药剂15 g/巢处理出现的新巢数量均显著高于25 g/巢处理。0.1%茚虫威15 g/巢处理, 校正蚁巢累计增加率高达124.98%, 0.08%茚虫威饵剂15 g/巢处理为89.05%; 0.08%和0.1%茚虫威饵剂25 g/巢处理, 校正蚁巢累计增加率分别为12.00%和51.34%。施用15 g/巢饵剂后2 d开始有大量工蚁尸体被丢弃, 至药后4 d弃尸量达最大值, 0.08%和0.1%茚虫威饵剂处理弃尸量分别为330.5头/巢和300.2头/巢, 随后呈逐步下降趋势, 至14 d, 弃尸量降至最低。施药后8 d内弃尸量达总弃尸量75.26%以上, 至药后10 d, 已达总弃尸量的90.08%以上。施用0.08%和0.1%茚虫威饵剂25 g/巢的处理新蚁巢出现较少, 表明施用相对低剂量的饵剂, 更容易引起蚁巢迁移。红火蚁的弃尸行为主要发生在饵剂施用后的前8 d。 相似文献
2.
Daisuke Takahashi 《Ecology of Freshwater Fish》2008,17(1):71-77
Abstract – Age at maturity in males of the freshwater goby Tridentiger brevispinis , a species with exclusive paternal care, was investigated in two populations in Lake Biwa, Japan, that differed markedly in nest site abundance. At Ohmi-maiko, where nest sites were scarce, most males matured at age 3, and mean body size of males guarding eggs in nests was larger than that of males sampled randomly (including both guarding and nonguarding males) in the population. Conversely, at Minamihama, where nest sites were abundant, many males matured at age 1, and there was no difference in body size between guarding males and males collected randomly. The slope of regression lines between body size of the guarding male and the number of eggs in his nest was greater in Ohmi-maiko than in Minamihama. These results suggest that the shortage of nest sites enhances reproductive success in larger males, probably through male–male competition for nest sites and female mate choice for larger males. I conclude that in nest spawners, the availability of nest sites should strongly affect life-history traits of males through sexual selection. 相似文献
3.
通过孢子分离,小白球分离都在人工合成培养基上萌发成菌丝,形成小白球,证实小白球是鸡(土从)菌生活循环中的一个发育阶段.鸡(土从)菌担孢子萌发的单核菌丝,经过锁状联合发育成双核菌丝,继而形成小白球,但难以在培养基上长出子实体,而在蚁巢上合轴交叉的菌丝交织成小白球,再发育成原基,在适宜的环境条件下鸡(土从)菌破土而出形成子实体.本研究从无性循环及有性循环两方面初步阐明了鸡(土从)菌的生活史. 相似文献
4.
浙江江山市林区食虫鸟类初步调查 总被引:2,自引:1,他引:2
本文报道了1987~1989年在江山市林区鸟类调查的初步结果。记录鸟类102种,隶属12目29科。留鸟52种,冬候鸟32种,夏候鸟18种。其中重要的食虫鸟类有46种,值得很好保护,特别是在该区繁殖的鸟类。文末记述了6种鸟巢。 相似文献
5.
Qing-ming wu Hong-fei ZOU Jian-zhang MA 《林业研究》2014,25(4):947-952
White-naped crane (Grus vipio) is a globally threatened spe- cies. It is very important to analyze its nest site selection in circum- stances where there are multiple disturbances, and also helpful to accu- mulate valuable information about this threatened species and supply scientific suggestions for conservation and management. We studied nest site selection and the effects of environmental variables on nesting habits of white-naped crane at Zhalong National Nature Reserve, Qiqihar City, Heilongiiang, China, during March-May of 2002-2008. White-naped crane responded and adapted to changes in the quality of the spatial environments of landscape and microhabitat under multiple environ- mental disturbances. Nest site selection included two scales and two choices, namely the choice of nest site habitat type within the macro-habitat scale and nest site micro-habitat selection within the mi- cro-habitat scale. Nest sites were recorded only in reed marshes. The choice of nest site micro-habitat included three basic elements and six factors, namely incubation element (nest parameters factor, incubation temperature factor and incubation humidity factor), safety element (pro- tection factor and concealment factor), and food element (water factor). Water, remnant reed clusters, and fire were major resource management challenges during the breeding period for the white-naped crane in this Reserve. 相似文献
6.
7.
Abstract Variation in brood abandonment was explored by conducting partial brood removals from smallmouth bass, Micropterus dolomieu Lacepède, nests in two north temperate lakes. In both lakes, percent of the brood removed had no effect on nest failure rates. Nest failure prior to offspring swim‐up was more common, but unrelated to brood size after removal, in the lake with higher post‐spawning mortality and lower growth and fecundity. Brood size after removal was negatively related to nest failure in the lake with high survival, growth and fecundity. Nests guarded by young males failed more frequently than those of old males, and young broods failed more frequently than old broods. Dynamic programming and logistic regression models developed to predict nest fate worked better for the lake with selective pressures that theoretically favoured abandonment (e.g. high post‐spawning mortality). Both models identified male age and brood age as important factors in predicting nest fates. Because nest success is related to the age of the parent, this could have consequences for overall nest success for populations with different demographics. 相似文献
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9.
Abstract – Bluegill ( Lepomis macrochirus ) primarily reproduce in spawning colonies. We assessed habitat characteristics at 15 bluegill spawning colonies in a South Dakota glacial lake. Nesting sites were visually identified and angling was used to verify the species of nesting fish. Habitat characteristics were measured at each nesting site and compared with those measured at 75 randomly selected sites. In Lake Cochrane, mean water depth of spawning colonies was 1.0 m. Of the 13 habitat characteristics measured, four (substrate type, substrate firmness, vegetation density and dissolved oxygen levels) were significantly different ( P ≤ 0.05) between nesting and random sites. Every bluegill nest site contained gravel substrate, despite the availability of muck, sand and rock. Substrate firmness was indexed at 0-cm penetration and vegetation density was low at all nesting sites. Additionally, bluegills selected nesting locations with relatively moderate dissolved oxygen levels. Lake Cochrane bluegill nest sites consisted of shallow, gravel areas with short, low-density, live submergent Chara vegetation. 相似文献
10.