温室无沙养鳖工艺的初步研究

温室无沙养鳖法是对传统的有沙养鳖进行重大改革，其主要特点是能克服底质和池水极易污染的问题，从而改善栖息环境，提高放养密度。“人工鳖巢”是一种较理想的栖息隐蔽物，有它替代河沙，排污比较彻底，洗池省工省时。试验证明，无沙养鳖法具有高产、优质、低成本，以及观察检查，饲养管理和干池捕鳖均很方便等优点。这种新工艺对稚鳖和幼鳖都适用，但它是一项综合性的养殖技术，除用“人工鳖巢”替代河沙作鳖的栖息隐蔽物外，在饲     

香港垃圾倾倒活动有害渔业环境

香港方面在外伶仃岛正北约 ４．５公里处设立垃圾区，长期倾倒淤泥、垃圾。为查明倾倒活动与附近渔业环境的关系，在垃圾区附近海域进行了９个测站的表面沉积采样调查，每个样品测定沉积化学成分和粒级分类等１３个项目。根据调查所得的第一手资料，应用模糊聚类分析方法，鉴别出香港垃圾的倾倒活动，使外伶仃岛北部区域复盖了新生沉积层，并证实位于外伶仃岛北海岸的石冲湾网箱养殖区处于较主要的受影响区域内。     

When and why do smallmouth bass abandon their broods? The effects of brood and parental characteristics

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.     

Habitat characteristics at bluegill spawning colonies in a South Dakota glacial lake

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.     

湘潭市郊菜园土及部分蔬菜重金属和氟污染状况的研究

湘潭市菜园土全部受到Cd的污染,蔬莲65％超过食品卫生标准,所有菜园土均有Pb污染,其中轻度污染4个区,中度污染2个区,以0.3ppm为标准,则蔬菜含Pb超标率达100％,如以0.6ppm为摄入限量浓度,蔬菜68％超限、Cu,Zn在土壤中均有积累,但末达到引起蔬菜污染的程度,土壤采用湘江流域背景值加2倍标准差作为污染起始值进行评终,3类菜园士对几种重金属元素的积累总趋势为:煤灰菜园土>红菜园土>潮菜园土,污染物质对土壤重金属积累的影响是:煤灰垃圾>污水灌溉>气污,但F的污染则与上相反、白菜和包菜对Cu,Zn,Cd,Pb的蓄积能力顺序相同,均为Cd>Zn>Cu>Pb,对每种元素而言则白菜的蓄积能力均大于包菜。     

信阳市生态环境问题现状与保护对策研究

通过对信阳市目前主要存在的生态环境问题的分析 ,有针对性的提出了生态保护的对策 ,旨在为建设良好的信阳市生态环境提供参考依据     

Bt转基因玉米的抗虫效果及其对田间动物种群影响的初步研究

通过比较Bt转基因玉米和常规玉米（丹玉13号）的玉米螟卵量、被害株数及田间一些动物的种群数量，结果表明：Bt转基因玉米对玉米螟具有较高的抗性，而且这种作用是持久的、稳定的。另外还发现，Bt转基因玉米对非鳞翅目昆虫及其他动物的影响甚微，可以认为Bt转基因玉米对田间生态环境是安全的。     

八种肉用犬的繁殖性能研究

本文通过对狼犬、鞑子犬、青龙犬、大丹犬、英卡犬、沙皮犬、藏鳌、拿波伦犬等8个品种192只犬繁殖性能研究。发现这八种犬的发情季节多集中在3月份和10～11月份，发情持续时间一般为14d，交配最佳时间为11d。配种次数与窝产仔数间不存在相关。     

The use of artificial nest boxes by Siberian flying squirrels (Pteromys volans) in South Korea

In this study, we examined the use of artificial nest boxes by Siberian flying squirrels (Pteromys volans) in three coniferous and mixed forests in Gangwon Province, South Korea. Six hundred and twelve boxes with different sized entry holes (ranging from 3 to 7 cm in diameter) were placed in the forests between 2004 and 2009. Pteromys volans used nine boxes in the coniferous forests and two boxes in the mixed forests. The squirrels only used boxes with entrance holes measuring 3.5, 4, and 5 cm in diameter, showing a strong and moderate preference for boxes with 5 and 4-cm holes, respectively, and a strong avoidance for boxes with 3- and 7-cm holes. Therefore, we suggest placing artificial nest boxes with entrance holes 5 cm in diameter to encourage breeding activity. Most nests made in the artificial boxes were composed of fibrous materials from woody vines. We recommend placing artificial nest boxes with holes of 5-cm diameter in coniferous forests, which support dense populations of P. volans, to survey whether this approach would positively affect the breeding habits and population maintenance of this species.