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941.
上海部分地区市民环境意识调查分析 总被引:6,自引:0,他引:6
根据上海市曹杨街道垃圾分类收集的问卷调查结果,分析了社区市民的环境与环境行为的现状和特点。从中发现67%的人了解垃圾分类收集的方法;89%的人认识到垃圾分类收集的必要性;市民通过不同的媒体获得环保信息来提高环境意识。分析表明市民的文化程度、收入、职业等背景并不会从根本上影响他们的环境行为,但人们的环境意识对他们的环境行为起着相当大的作用。因此环境教育和环保宣传应作为提高公众环境意识的主要途径之一。 相似文献
942.
943.
废旧电器回收再生利用是开辟“城市矿山”的资源源泉。从技术、经济、社会三个层面分析其物质、价值和行为三个形态的循环机理及其互动关系,价值循环要考虑自然资源资本和环境保护与恢复的成本来分析其价值保值与增值过程;行为循环要以基于生产者责任延伸制的主体责任体系为纽带,分析其行为活动规律及其相互关系;物质循环要按照循环经济的原则考虑各种物质形态的有效转换与有机联系,以实现资源到资源的物质闭路循环。 相似文献
944.
Liu Ruiping Yang Yanling Li Guibai He Wenjie Han Hongda 《Frontiers of Environmental Science & Engineering in China》2007,1(2):240-245
This study focused on the adsorptive behaviors of humic acid onto freshly prepared hydrous MnO2(s) (δMnO2), and investigated the feasibility of employing δMnO2 for humic acid removal from drinking water. Effects of such parameters as molecular mass of humic acid, kinds of divalent
cations on adsorptive behaviors and possible mechanisms involved were investigated. This study indicated that humic acid with
higher molecular mass exhibited more tendency of adsorbing onto δMnO2 than that with lower molecular mass. Ca2+ facilitated more humic acid adsorption than Mg2+; UV-Vis spectra analysis indicated higher capabilities of Ca2+ coordinating with acidic functional groups of humic acid than that of Mg2+. Additionally, ζ potential characterization indicated that Ca2+ showed higher potential of increasing gz potential of δMnO2 than Mg2+. Ca2+ of 1.0 mmol/L increased ζ potential of δMnO2 from −37 mV (pH 7.9) to +7 mV (pH 7.2), while 1.0 mmol/L Mg2+ increased to lower value as −9 mV (pH 6.5), correspondingly. Fourier transform infrared (FTIR) spectra demonstrated the adsorption
of humic acid onto δMnO2, showing the important roles of-COO− functional groups and surface Mn-OH in the adsorption of humic acid onto δMnO2.
Translated from Acta Scientiae Circumstantiae, 2005, 25(3): 351–355 [译自: 环境科学学报] 相似文献
945.
Some territorial animals exhibit a form of social recognition, commonly termed the "dear enemy effect", in which territory residents display lower levels of aggression toward familiar neighbors compared to unfamiliar individuals who are non-territorial "floaters". Despite the widespread occurrence of territorial social systems and use of acoustic signals for communication in anuran amphibians, only two previous studies have demonstrated vocally mediated dear enemy behavior in a territorial frog. In this study, I conducted neighbor-stranger discrimination playback experiments in a third species of territorial frog, the strawberry dart-poison frog, Dendrobates pumilio (Anura, Dendrobatidae). In the first experiment (n=24), I broadcast the calls of a subject's nearest neighbor and the calls of an unfamiliar individual from the approximate midpoint between the subject's and the neighbor's territories. Although males responded to the stimuli, they did not exhibit differential responses to the calls of neighbors and strangers. In a second experiment (n=22), I broadcast the calls of a neighbor and a stranger to subjects through a speaker located in the approximate center of the neighbor's territory. Males also responded to the playback, although less intensely than in the first experiment, but no discrimination between the calls of neighbors and strangers was found. Thus, territorial males of the strawberry dart-poison frog appear not to discriminate behaviorally between the advertisement calls of neighbors and strangers. Several proximate and ultimate-level hypotheses for this lack of vocally mediated neighbor-stranger discrimination are discussed.Communicated by T. Czeschlik 相似文献
946.
A criterion validity test of the contingent valuation method: comparing hypothetical and actual voting behavior for a public referendum 总被引:1,自引:0,他引:1
Christian A. Vossler Joe Kerkvliet 《Journal of Environmental Economics and Management》2003,45(3):631-649
This study pursues external validation of contingent valuation by comparing survey results with the voting outcome of a Corvallis, Oregon, referendum to fund a riverfront improvement project through increased property taxes. Survey respondents hypothetically make a voting decision—with no financial consequences—on the upcoming referendum. The survey sample consists of respondents verified to have voted in the election. We use available precinct-level election data to compare the proportion of “yes” survey and referendum votes as well as estimate voting models and mean willingness to pay (WTP) based on the two sets of data. We find that survey responses match the actual voting outcome and WTP estimates based on the two are not statistically different. Contrary to similar studies, our statistical results do not depend on re-coding the majority of “undecided” survey responses to “no.” Furthermore, such a re-coding of responses may be inappropriate for our data set. 相似文献
947.
繁殖期白头鹤觅食地活动的时间分配和日节律 总被引:5,自引:0,他引:5
2004年4~6月在黑龙江大沾河湿地自然保护区内,采用野外直接观察法对野生白头鹤在觅食地的活动节律进行了研究.结果表明:①繁殖期白头鹤在觅食地各种行为活动有一定的时间分配规律.在繁殖前期,雌、雄白头鹤全天(5:30~18:00)成对在觅食地活动,雄性个体以取食、警戒、游走、保养和求偶为主要行为,雌性个体以取食、警戒、游走和保养为主要行为;到繁殖后期,雌、雄白头鹤每天有两个时间段单独在觅食地活动(4:00~6:00和17:00~19:00),无论雌雄个体,均无求偶行为.②白头鹤雌、雄个体间保养行为差异极显著(P<0.001),警戒和求偶行为差异显著(P<0.05),取食、游走行为具有一定的差异.③在麦田和池塘2种微地貌之间,白头鹤的取食、求偶行为具极显著差异(P<0.001),警戒行为具显著差异(P<0.05).④在繁殖期的不同阶段以及不同的天气情况下白头鹤的各种行为均具有一定差异.图1表2参15 相似文献
948.
Resource value is often considered the most important nonstrategic variable in the fighting behavior of invertebrates. In
our study, we tested whether the experience of shells of a given quality, occupied in the recent past, might affect the agonistic
behavior of the hermit crab Pagurus longicarpus. We analyzed the fights battled by 84 test crabs against size-matched unknown rivals before (premanipulation phase) and after
(postmanipulation phase) having modified the quality of the domicile shell of the contestants. Specifically, we compared the
behavior of crabs that had been subject to either a worsening or an improvement in the quality of their shell with crabs that,
although being similarly subject to a shell manipulation, occupied a shell of the same quality as in the premanipulation phase.
We found that the crabs subject to a worsening in the quality of their shell were more aggressive than those subject to its
improvement and that the former were even more aggressive than those that occupied a bad quality shell also in the premanipulation
phase. Crabs seemed not to gather information about the opponent’s shell during fights or not to use this information, most
often behaving in accordance with the quality of the domicile shell. These results are clear in showing the role played by
the experience of a previously occupied shell, also confirming that the agonistic behavior of P. longicarpus is mainly based on decision rules of the type “own resource value dependency.” 相似文献
949.
JAIME BOSCH§ PEDRO A. RINCÓN LUZ BOYERO† IÑIGO MARTÍNEZ-SOLANO‡ 《Conservation biology》2006,20(1):180-189
Abstract: Amphibians are declining worldwide because of multiple factors, including human-mediated introduction of fishes into naturally fishless areas. Although several studies have focused on the effect of exotic fishes on native amphibians breeding in ponds or lakes, little is known about their effects on stream-breeding species. We studied the effects of introductions of native brown trout ( Salmo trutta ) and exotic brook trout ( Salvelinus fontinalis ) on the stream-breeding, endemic Iberian frog ( Rana iberica ) in a protected area in central Spain. We assessed occurrence patterns of tadpoles and salmonids and compared habitat use of the three species. We also determined experimentally whether chemical cues from salmonids elicited antipredator behavior in tadpoles. Finally, we assessed the relative influence of tadpole habitat preferences, differences in salmonid species, and invasion geography on tadpole occurrence. Despite widely overlapping habitat preferences, tadpoles and trout did not coexist, with the former restricted to fishless habitats. Tadpoles detected chemical cues from both trout species and reacted by decreasing their activity, although the response toward the native brown trout was stronger. The residual distribution of Iberian frogs in Peñalara is better explained by the geography of fish invasions than by the fish species involved. Measures such as fish extirpation from certain areas, aimed at recovering lost habitat and improving connectivity among remaining populations of Iberian frogs, seem critical for the species' long-term survival in central Spain. 相似文献
950.
Karen M. Kester Steven C. Peterson Frank Hanson D. Michael Jackson R. F. Severson 《Chemoecology》2002,12(1):1-10
Summary. Field observations indicated that hornworms select feeding sites non-randomly on tobacco. We tested the hypotheses that differences
in feeding site locations of larvae of Manduca
sexta L. and Manduca
quinquemaculata (Haworth) (Lepidoptera: Sphingidae) on tobacco could be explained by differential nicotine concentrations within plants and
leaves, species-specific responses to nicotine, or pressure exerted by natural enemies. Results showed that third-instar larvae
of M. sexta fed more proximally and centrally on the leaf, whereas M. quinquemaculata fed more distally. Within-plant selection of leaves did not differ; both species selected leaves in the middle region of
the plant. Nicotine concentrations in a high nicotine genotype, NC95, varied within each leaf, increasing 2—3 fold from the
basal to apical portion of the leaf, and within each plant, increasing 7—10 fold from the first fully expanded leaf to the
twelfth (lowest) leaf. In laboratory bioassays, both Manduca species responded to nicotine as a feeding deterrent. Electrophysiological studies demonstrated that gustatory organs of
both species responded to nicotine at concentrations found in tobacco leaves and that M. quinquemaculata generally showed a less vigorous response to nicotine than M. sexta. Field mortality of M. sexta due to parasitism by Cotesia
congregata (Say) and to parasitism and predation combined differed among feeding sites; predation alone did not. Results suggest that
although nicotine concentration and species specific responses to nicotine play a role in determining feeding site locations,
pressure exerted by natural enemies, especially parasitism by C. congregata, is more important.
Received 22 February 2000; accepted 20 July 2001. 相似文献