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21.
按离路基不同距离采集土壤、麦苗和籽粒样品, 在测定样品重金属 (Pb、Cd、Zn、Cr和Cu) 的基础上, 开展了路旁土壤-小麦系统重金属分布、积累和污染状况分析, 并对膳食小麦 (Triticumaestivum) 引起的健康风险进行了评价。结果表明:1) 土壤-小麦系统重金属含量随着离开路基距离的增加呈先增加后减少的趋势, 土壤重金属含量>麦苗重金属含量>籽粒重金属含量。2) 麦苗和小麦籽粒对土壤重金属富集能力的大小顺序均为Cu>Cd>Zn>Pb>Cr, 麦苗对重金属的富集能力大于小麦籽粒。3) 膳食小麦所致的Cd个人健康风险较大。 相似文献
22.
Major roads and highways disrupt ecological flows and create barriers or filters to the movement of many species of wildlife, including gliding mammals. Mitigating these impacts presents major challenges for road authorities. One approach has been the retention of forest vegetation in median strips to serve as ‘stepping stones’ for gliding mammals to cross road gaps otherwise beyond their glide capacity. A recently upgraded section of the Pacific Highway through tall open forest near Bonville in north‐east New South Wales retained forest within two 10‐ to 45‐m‐wide median strips separating each carriageway and a service road. We investigated whether Sugar Gliders (Petaurus breviceps) used these median strips to cross an 85 to 135 m‐wide road corridor. Three radio‐collared Sugar Gliders (one male and two females) moved between both highway medians and forest on either side of the road corridor during 32 days of radio‐tracking. Although the sample size is small, these results suggest that highway median strips, featuring mature vegetation with a major den tree, can provide ‘stepping stones’ for gliding mammals to cross a highway that would otherwise function as a movement barrier or filter. Longer‐term research with greater numbers of animals at this and other sites is required to determine whether such strips would be commonly used when den trees are absent and whether gliding via median strips may also increase road mortality of the species. 相似文献
23.
Furuya Hirokazu; Ikezoe Koji; Shigeto Hiroshi; Ohyagi Yasumasa; Arahata Hajime; Araki Ei-ichi; Fujii Naoki 《Dreaming》2009,19(4):232
To categorize four types of sleep- and non-sleep-related hallucinations experienced by normal people and classify ghost or ghost-like stories by these categories. A total of 183 reliable tales of ghosts [41 from “Tohno Monogatari” (Tohno Folktales) and 142 from “Nihon Kaidan Shu” (Ghosts Tales of Japan)] are classified into hallucinations that are sleep-related hallucinations [hypnagogic hallucination-like (HyH) and REM sleep behavior disorder or somnambulism-like (RBDS) tales] and sleep-unrelated [vivid hallucination-like (VH) and highway hypnosis-like (HHy) tales] according to the criteria. Sixty to 70% of these tales can be classified into these four types of hallucinations. Further, sleep-related hallucinations increased from 17.0% to 36.6% in about 40 years. Our criteria will be useful to classify hallucinations experienced by normal people and to elucidate the mechanisms of these kinds of hallucinations experienced in neurodegenerative or psychological disorders. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
24.
Highway underpasses are a common management tool used to lessen wildlife-vehicle collisions on roadways. Despite their widespread use, the effects of predator-prey interactions and human disturbances on wildlife within underpasses have not been well studied. To understand the effect of species interactions and human disturbances on wildlife traveling through underpasses, we analyzed camera data from 3 underpasses in Hallelujah Junction Wildlife Area, Sierra County, California, USA, from June 2017 to December 2018. We recorded 3,589 detections, which were predominately mule deer (Odocoileus hemionus), rodents, lagomorphs, California quail (Callipepla californica), bobcats (Lynx rufus), mountain lions (Puma concolor), and coyotes (Canis latrans). We used occupancy modeling and daily activity estimates to analyze species' spatial and temporal activity within the underpasses. Predator-prey interactions and human disturbances were among the most important factors that influenced wildlife travel through the underpasses. Mule deer avoided underpasses highly used by mountain lions, and mountain lions followed mule deer daily temporal activity patterns and seasonal activity patterns. These results indicate that predator-prey interactions influenced deer and mountain lion use of the underpasses. Coyotes favored underpasses and seasons with higher rodent and lagomorph presence, suggesting that the presence of prey was also important to coyote use of the underpasses. Coyotes, mountain lions, and bobcats all exhibited either temporal or spatial avoidance of human activity within the underpasses. California quail avoided predators within the underpasses and favored underpasses and times with high human activity. Our study suggests that underpass managers need to closely monitor the effect of predator-prey interactions and human activity on wildlife within underpasses to ensure these interactions do not discourage wildlife from using them. © 2019 The Wildlife Society. 相似文献
25.
Adrian Peace 《The Australian journal of anthropology》2013,24(1):99-114
This paper explores the cultural significance of ephemeral public greetings on the highways of Australia's Northern Territory. Despite the exceptional speed at which vehicles pass one another and the fact that such salutations are mostly between travellers who have no acquaintance with one another, few drivers fail to acknowledge the co‐presence of others on the highway. The main concern of this account is to detail how this greeting system works, including the diverse meanings which can be attached to participation in it. In conclusion, it is suggested that this is a form of phatic communication which, as Malinowski (1923) said, eschews engagement with weighty economic and political issues, but contributes significantly to a sense of community between those involved. 相似文献
26.
极端干旱区防护林地土壤微生物多样性 总被引:5,自引:0,他引:5
土壤微生物在森林土壤中有重要功能.采用传统培养、脂肪酸鉴定和PCR-DGGE 3种方法分别研究了塔里木沙漠公路防护林地土壤微生物数量、脂肪酸种类和细菌DNA片段的多样性,从微生物学角度为塔里木沙漠公路防护林的管理提供理论依据.结果表明,塔里木沙漠公路防护林的建设促进了风沙土土壤微生物的发育,随着防护林定植年限的增加,土壤微生物数量、脂肪酸和细菌DNA片段的多样性指数明显增大;土壤微生物区系组成中,细菌是优势类群,占微生物总数80%以上,而真菌很少,不到微生物总数1%,但在不同土层间有所差异;传统培养法与现代生物标记和分子生物学方法对塔里木沙漠公路防护林地土壤微生物多样性的研究结果基本一致,说明塔里木沙漠公路防护林的建设使林地土壤生物活性有所增强,有利于林地土壤养分循环与利用. 相似文献
27.
青藏公路对藏羚羊、藏原羚和藏野驴活动的影响 总被引:2,自引:2,他引:2
2003年8月和2004年8月,在可可西里国家自然保护区通过实地调查,分析了青藏公路运营对藏羚羊(Pantholops hodgsoni)、藏原羚(Procapra picticaudata)和藏野驴(Equus kiang)行为活动的影响.结果表明:藏野驴对青藏公路形成了回避,其在距路基1 001~2 000和2 001~3 000 m区域内的种群密度显著高于0~500 m的区域(P<0.05);青藏公路对藏羚羊、藏原羚的行为活动产生了一定程度的干扰,尤其是对藏羚羊,其在距路基0~500 m区域内的行为活动与距路基2000 m之外的区域具有极显著差异(P<0.01).同时,因其群体数量大,个体通过公路所花费的时间长,需要很长的车辆行驶间隔才能通过公路,故受车辆运输的干扰最大,无法顺利通过公路.研究还发现,在白天的不同时间段,藏羚羊、藏原羚在公路附近的数量分布与各时间段内的车流量呈极显著负相关,这有利于其穿越公路,说明野生动物通过自身的适应和行为调节可以减少环境改变所造成的影响. 相似文献
28.
城郊公路两侧主要森林类型铅含量及分布规律 总被引:28,自引:3,他引:28
对南京城郊312国道两侧主要森林类型林木不同器官中Pb含量和分布规律的研究表明,不同树种、同一树种不同器官中Pb含量有明显差异.火炬松对Pb污染的净化能力强于杉木、栎树.汽车尾气排放的Pb污染影响范围在离公路两侧100m以内,主要在40m以内范围.有林地土壤由于有林木及林下植被的覆盖,其Pb含量(尤其是表层0~20cm范围内)明显降低,说明林分可有效地降低土壤中Pb的污染程度.林木不同器官对Pb尘的吸附率在180%~281%之间,以叶片吸附能力最强;不同树种比较,以松树吸附率为高 相似文献
29.
NORRIS L. DODD JEFFREY W. GAGNON SUSAN BOE RAYMOND E. SCHWEINSBURG 《The Journal of wildlife management》2007,71(4):1107-1117
Abstract: Highways have significant direct and indirect impact on natural ecosystems, including wildlife barrier and fragmentation effects, resulting in diminished habitat connectivity and highway permeability. We used Global Positioning System (GPS) telemetry to assess Rocky Mountain elk (Cervus elaphus nelsoni) permeability across a 30-km stretch of highway in central Arizona, USA, currently being reconstructed with 11 wildlife underpasses, 6 bridges, and associated ungulate-proof fencing. The highway was reconstructed in phases, allowing for comparison of highway crossing and passage rates during various stages of reconstruction. We instrumented 33 elk (25 F, 8 M) with GPS receiver collars May 2002 to April 2004. Our collars accrued 101,506 GPS fixes with 45% occurring within 1 km of the highway. Nearly 2 times the proportion of fixes occurred within 1 km of the highway compared with random. We think elk were attracted to the highway corridor by riparian—meadow foraging habitats that were 7 times more concentrated within the 1-km zone around the highway compared with the mean proportion within elk use areas encompassing all GPS fixes. Elk crossed the highway 3,057 times; crossing frequency and distribution along the highway were aggregated compared with random. Crossing frequency within 0.16-km highway segments was negatively associated with the distance to riparian—meadow habitats (rs = -0.714, n = 190, P < 0.001). Mean observed crossing frequency (92.6 ± 23.5 [SE] crossings/elk) was lower than random (149.6 ± 27.6 crossings/elk). Females crossed 4.5 times as frequently as males. Highway permeability among reconstruction classes was assessed using passage rates (ratio of highway crossings to approaches); our overall mean passage rate was 0.67 ± 0.08 crossings per approach. The mean passage rate for elk crossing the highway section where reconstruction was completed (0.43 ± 0.15 crossings/approach) was half that of sections under reconstruction and control sections combined (0.86 ± 0.09 crossings/approach). Permeability was jointly influenced by the size of the widened highway and associated vehicular traffic on all lanes. Crossing frequency was used to delineate where ungulate-proof fencing yielded maximum benefit in intercepting and funneling crossing elk toward underpasses, promoting highway safety. Use of passage rates provides a quantitative measure to assess permeability, conduct future pre- and postconstruction comparisons, and to develop mitigation strategies to minimize highway impacts to wildlife. 相似文献
30.
不同人工灌木与草混播群落中4种灌木根系分布的研究 总被引:2,自引:0,他引:2
通过对3种人工群落中4种优良水土保持灌木荆条、柠条、胡枝子、紫穗槐的根系分布的研究,分析和探讨这4种灌木在不同群落中根系生物量分布,地上、地下生物量相关性及有效根密度的差异.结果表明:(1)紫穗槐在不同人工群落中的地下生物量相对稳定;(2)群落Ⅰ(胡枝子80/柠条80 紫穗槐30/荆条20 苇状羊茅150/百脉根100)的植物配置灌木根系生物量最大;(3)4种灌木地上、地下生物量有较强的相关性,地上生物量均随地下生物量的增加而提高;群落Ⅰ有效根密度总和远大于群落Ⅱ、Ⅲ.可见,紫穗槐具有良好的混播性能,群落Ⅰ的植物配置模式相对合理. 相似文献