Estimated home ranges can misrepresent habitat relationships on patchy landscapes

Home ranges of animals are generally structured by the selective use of resource-bearing patches that comprise habitat. Based on this concept, home ranges of animals estimated from location data are commonly used to infer habitat relationships. Because home ranges estimated from animal locations are largely continuous in space, the resource-bearing patches selected by an animal from a fragmented distribution of patches would be difficult to discern; unselected patches included in the home range estimate would bias an understanding of important habitat relationships. To evaluate potential for this bias, we generated simulated home ranges based on optimal selection of resource-bearing patches across a series of simulated resource distributions that varied in the spatial continuity of resources. For simulated home ranges where selected patches were spatially disjunct, we included interstitial, unselected cells most likely to be traveled by an animal moving among selected patches. We compared characteristics of the simulated home ranges with and without interstitial patches to evaluate how insights derived from field estimates can differ from actual characteristics of home ranges, depending on patchiness of landscapes. Our results showed that contiguous home range estimates could lead to misleading insights on the quality, size, resource content, and efficiency of home ranges, proportional to the spatial discontinuity of resource-bearing patches. We conclude the potential bias of including unselected, largely irrelevant patches in the field estimates of home ranges of animals can be high, particularly for home range estimators that assume uniform use of space within home range boundaries. Thus, inferences about the habitat relationships that ultimately define an animal's home range can be misleading where animals occupy landscapes with patchily distributed resources.     

以监测网深化环境监测工作

本文根据多年从事监测工作的体会和对各类监测站的调查研究,评述了当前地方监测工作和行业、企业监测工作中存在的一些问题,提出了用切实运转的监测网来深化和开拓监测工作的建议,并对监测网的组建和运转作了较为可行的建议和设想。     

矿业环境相邻关系立法初探

矿业环境相邻关系的界定是相应环境产权私人化的途径。由矿业环境相邻权与矿业成员环境权双向对接组成的环境相邻关系,通过法律来约束矿山企业的环境相邻权和激励相邻对方的成员环境权而共同保护矿业环境。矿山企业一方给相邻对方合理施加容忍义务,相邻对方应当容忍非实质性的或当地通行的影响。成员环境权的保护,是基于物权而行使消除危险、排除妨害和恢复原状的请求权,基于债权而行使侵害赔偿请求权。     

阿图什市不同类型的炉灶及能源消耗现状调查评价

对不同类型的炉灶煤耗及污染物的排放量进行了定量计算,在大量的统计资料及监测数据的基础上,分析阿图什市各类型炉灶燃煤及污染物排放的情况,并通过定量计算进行了探讨,提出相关的对策和建议.     

Risk tolerance and pilot involvement in hazardous events and flight into adverse weather

INTRODUCTION: According to Lopes [Lopes, L.L. (1987). Between hope and fear: The psychology of risk. Advances in Experimental Social Psychology, 20, 255-295] tolerance of risk may be governed by sensitivity to either the opportunities for gain or threats of loss involved. Methods: In the initial study, qualified pilots were presented with 36 written flight scenarios that varied in the levels of opportunity and threat present. The pilots rated the likelihood that they would undertake each flight. Pilots were largely risk averse, as their ratings were all significantly influenced by threat. Results: The pilots whose ratings were significantly influenced by opportunity had been involved in more hazardous aviation incidents than the other pilots. In the final study, 32 qualified pilots completed both the risk tolerance measure and a simulated flight into adverse weather. The pilots who continued flying into adverse weather were less risk averse compared to the pilots who diverted. This further highlighted the link between risk tolerance and risk-taking, and suggested that some pilots may fly into adverse weather because of a greater tolerance of risk. Impact on Industry:The studies provide evidence that a measure of risk tolerance can predict potential accident involvement amongst general aviation pilots.     

Distribution of leeches in aquatic ecosystems of the city of Yekaterinburg and its vicinity

Ecological features and species composition of leeches were studied in 25 water bodies located in the city of Yekaterinburg and its vicinity. Specific features of their occurrence and distribution in water bodies of various types were analyzed. Dominant, mass, common, and rare species were distinguished.     

Toxicity of cobalt-complexed cyanide to <Emphasis Type="Italic">Oncorhynchus mykiss,Daphnia magna</Emphasis>, and <Emphasis Type="Italic">Ceriodaphnia dubia</Emphasis>

Background Cobalt cyanide complexes often result when ore is treated with cyanide solutions to extract gold and other metals. These have recently been discovered in low but significant concentrations in effluents from gold leach operations. This study was conducted to determine the potential toxicity of cobalt-cyanide complexes to freshwater organisms and the extent to which ultraviolet radiation (UV) potentiates this toxicity. Tests were also conducted to determine if humic acids or if adaptation to UV influenced sensitivity to the cyanide complexes. Methods Rainbow trout (Oncorhynchus mykiss), Daphnia magna, and Ceriodaphnia dubia were exposed to potassium hexacyanocobaltate in the presence and absence of UV radiation, in the presence and absence of humic acids. Cyano-cobalt exposures were also conducted with C. dubia from cultures adapted to elevated UV. Results With an LC50 concentration of 0.38 mg/L, cyanocobalt was over a 1000 times more toxic to rainbow trout in the presence of UV at a low, environmentally relevant irradiance level (4 μW/cm² as UVB) than exposure to this compound in the absence of UV with an LC50 of 112.9 mg/L. Toxicity was immediately apparent, with mortality occurring within an hour of the onset of exposure at the highest concentration. Fish were unaffected by exposure to UV alone. Weak-acid dissociable cyanide concentrations were observed in irradiated aqueous solutions of cyanocobaltate within hours of UV exposure and persisted in the presence of UV for at least 96 hours, whereas negligible concentrations were observed in the absence of UV. The presence of humic acids significantly diminished cyanocobalt toxicity to D. magna and reduced mortality from UV exposure. Humic acids did not significantly influence survival among C. dubia. C. dubia from UV-adapted populations were less sensitive to metallocyanide compounds than organisms from unadapted populations. Conclusions The results indicate that metallocyanide complexes may pose a hazard to aquatic life through photochemically induced processes. Factors that decrease UV exposure such as dissolved organic carbon or increased pigmentation would diminish toxicity.     

Home range overlap of mothers and their offspring in the sleepy lizard, Tiliqua rugosa

This paper reports a field investigation of interactions between juveniles and their mothers in the Australian sleepy lizard, Tiliqua rugosa. In their first spring season, juvenile lizards maintain home ranges largely within the home range of their mother. Juvenile home ranges are significantly smaller than those of adult males and females, and juveniles move significantly less often and significantly shorter distances than adults. While siblings were never found together in the spring, they showed a significant tendency to be closer to each other than if they were randomly located in their home ranges. Juveniles and mothers were never found together, nor was there any evidence for any positive (or negative) spatial association. Nevertheless, the extended tolerance of home range overlap represents a greater degree of mother-offspring association than has been previously reported for other lizards. Despite this, the level of parental care can only be described as minimal. Received: 20 June 1997 / Accepted after revision: 29 December 1997     

某厂煤气洗涤塔煤气泄漏中毒事故分析

针对某钢铁厂煤气事故,使用定性分析的方法,对喷淋塔泄水作业的试验数据进行了分析,煤气泄漏造成人员中毒原因进行了论证,得出了一些结论,并据此分析煤气泄漏后可能导致人员死亡的范围,为今后采取控制措施提供依据。     

一株耐盐嗜热菌Aneurinibacillus thermoaerophilus H7的分离及其油脂降解特性

针对高盐、高油餐厨垃圾高温堆肥功能菌株缺乏的问题,以大豆油为唯一碳源,通过测定生物量、脂肪酶活性和油脂降解率,从餐厨垃圾堆积处的土壤样品中分离筛选出一株嗜热油脂降解菌H7.通过形态特征、生理生化特征和16S rDNA序列分析,对筛选的菌株进行鉴定,考察其耐盐能力、油脂降解和生长特性.结果表明,菌株H7为嗜热嗜气解硫胺素...