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671.
Pablo D. Ribeiro John H. Christy Rebecca J. Rissanen Tae Won Kim 《Behavioral ecology and sociobiology》2006,61(1):81-89
Courting male fiddler crabs Uca terpsichores (1 cm carapace width) sometimes build mounds of sand called hoods at the entrances to their burrows. Males wave their single
enlarged claws to attract females to their burrows for mating. It was shown previously that burrows with hoods are more attractive
to females and that females visually orient to these structures. In this study, we test whether males also use their hoods
to find their burrows. We first determined the maximum distance that males can see and find a burrow opening without a hood.
Males were removed from their burrows and placed on the sand at a range of distances from a burrow opening. If they were more
than about 8 cm (seven units of eye-height) away, they were unable find the burrow. In contrast, males that were burrow residents
used a non-visual path map to return to their burrows from much greater distances. To determine if hoods help males find their
burrows when there are errors in their path maps, we moved residents 1–49 cm on sliding platforms producing errors equal to
the distances they were moved. Males with self-made hoods or hood models at their burrows relocated their burrows at significantly
greater distances than did males with unadorned burrows. Hood builders also relocated their burrows faster. Hence, hoods have
two functions: they attract females and they provide a visual cue that males use to find their burrows quickly and reliably
when their path maps fail.
An erratum to this article can be found at 相似文献
672.
Sigua GC Holtkamp ML Coleman SW 《Environmental science and pollution research international》2004,11(5):321-326
BACKGROUND, AIMS AND SCOPE: Dredged materials because of its variable but unique physical and chemical properties are often viewed by society and regulators as pollutants, but many have used these materials in coastal nourishment, land or wetland creation, construction materials, and for soil improvement as a soil amendment. Environmental impact assessment is an important pre-requisite to many dredging initiatives. The ability to reuse lake-dredge materials (LDM) for agricultural purposes is important because it reduces the need for off-shore disposal and provides an alternative to disposal of the materials in landfills. Additional research on disposal options of dredged materials are much needed to supply information on criteria testing and evaluation of the physical and chemical impacts of dredged materials at a disposal site, as well as information on many other aspects of dredging and dredged material disposal. While preliminary efforts are underway to provide information to establish criteria for land disposal, testing procedures for possible land disposal of contaminated sediments are still in their developing stage. The objective of this study (Part 1) was to quantify the effect of applied LDM from Lake Panasoffkee (LP), Florida on soil physico-chemical properties (soil quality) at the disposal site. This series of two papers aims at providing assessment of the efficacy of lake-dredged materials from LP especially its implication to environment (soil quality, Part 1) and agriculture (forage quality and pasture establishment, Part 2). METHODS: The experimental treatments that were evaluated consisted of different ratios of natural soil (NS) to LDM: LDM0 (100% NS:0% LDM); LDM25 (75% NS:25% LDM); LDM50 (50% NS:50% LDM); LDM75 (25% NS:75% LDM); and LDM100 (0% NS:100% LDM). Field layout was based on the principle of a completely randomized block design with four replications. The Mehlich 1 method (0.05 N HCl in 0.025 N H2SO4) was used for chemical extraction of soil. Soil P and other exchangeable cations (Ca, Mg, K, Al, and Fe) were analyzed using an Inductively Coupled Plasma (ICP) Spectroscopy. The effects of dredged materials addition on soil quality and compaction were analyzed statistically following the PROC ANOVA procedures. RESULTS AND DISCUSSION: Sediments that were dredged from LP have high CaCO3 content (82%) and when these materials were incorporated into existing topsoil they would have the same favorable effects as liming the field. Thus, sediments with high CaCO3 may improve the physical and chemical conditions of subtropical sandy pastures. The heavy and trace metal contents of LDM were below the probable effect levels (PEL) and threshold effect levels (TEL). Average values for Pb, Zn, As, Cu, Hg, Se, Cd, and Ni of 5.2 +/- 1.3, 7.0 +/- 0.6, 4.4 +/- 0.1, 8.7 +/- 1.2, 0.01 +/- 0.02, 0.02 +/- 0.02, 2.5 +/- 0.1, and 14.6 +/- 6.4 mg kg(-1), respectively, were below the TEL and the PEL. TEL represents the concentrations of sediment-associated contaminants that are considered to cause significant hazards to aquatic organisms, while, PEL represents the lower limit of the range of the contaminant concentrations that are usually or always associated with adverse biological effects. As such, the agricultural or livestock industry could utilize these LDM to produce forages. LDM should be regarded as a beneficial resource, as a part of the ecological system. Addition of LDM had significant (p < or = 0.001) effects on soil physico-chemical properties and soil quality. Compared with the control plots, the soils in plots amended with LDM exhibited: (1) lower degree of soil compaction; (2) an increase in soil pH, Ca, and Mg; (3) decrease in the levels of soil Mn, Cu, Fe, Zn, and Si; and (4) no significant change in the level of Na in the soil. Results have shown the favorable influence that LDM had on soil compaction. The treatment x year interaction effect was not significant, but the average soil compaction varied widely (p < or = 0.001) with LDM application. In 2002 and 2003, soil compaction of plots was lowered significantly as a result of LDM additions. The least compacted soils in 2002 and 2003 were observed from plots with LDM75 with mean soil compaction of 300 x 10(3) and 350 x 10(3) Pa, respectively. CONCLUSION: Beneficial uses of dredged materials from LP, Florida are both economical and environmental. Often these materials can be obtained at little or no cost to the farmers or landowners in south Florida. Environmentally, dredging of sediments that are rich in CaCO3 should restore the 19.4-sq km LP by removing natural sediments from the lake bottom to improve the fishery, water quality, and navigation of the lake. The bottom sediment materials from lakes, river, and navigational channels usually are composed of upland soil enriched with nutrients and organic matter. These materials should be regarded as a beneficial resource to be used productively and not to be discarded as spoil materials. RECOMMENDATION AND OUTLOOK: Land application of LDM from LP may not only provide substantial benefits that will enhance the environment, community, and society in south Florida, but also in other parts of the world especially those areas having tropical and subtropical climate with forage-based beef cattle pastures. The heavy and trace metal contents of LDM from LP were below the PEL and TEL. As such, the agricultural or livestock industry could utilize these LDM to produce forages (Part 2 of this study). LDM should be regarded as a beneficial resource, as a part of the ecological system. Further studies are still needed to determine whether the environmental and ecological implications of LDM application are satisfied over the longer term. 相似文献
673.
烟气脱硫石膏及其建材资源化研究 总被引:17,自引:0,他引:17
介绍了作者在烟气脱硫石膏及其作为主要原料制备建筑石膏、粉刷石膏、石膏砌块(条板)、纸面石膏板、腻子、水泥缓凝剂、二水石膏胶结材等建材资源化方面的研究结果。结果表明,烟气脱硫石膏的品位较高,便于利用,是建材工业的宝贵资源,应进一步加大研究开发力度。 相似文献
674.
通过对实验分析质量保证工作中存在的实际问题进行了论述;从仪器条件、实验样品前处理以及分析测定方法的选择等方面对环境标准样品的使用,及其对实验分析质量控制的影响进行了分析,并提出了相应的合理化建议。 相似文献
675.
This article presents a case study of a successful effort to reach agreement on one of the most intractable environmental issues of our time: wolf management. This case is unusual in several ways. In this case, the members of the negotiating team were ordinary citizens rather than leaders of organized groups. This team was given an unusually high level of authority to write the plan as they saw fit; the agency pledged to implement “whatever they came up with.” The agency convened the process, but agency personnel were not members of the team and attended only when they were invited. The team members were able to reach agreement on this tough issue even though polar opposites were at the table—one who felt that wolves are a “spiritual essence” and another who felt that, as he put it, “wolves, coyotes, and cockroaches have a lot in common”. They produced a detailed plan that addressed all the issues in just 5 months. Another unusual aspect of this effort is that the final agreement does not list the team members. They explained that they wanted their plan to “stand alone” and be judged based on what it said, not on who was involved.However, just after their agreement was completed, a new, pro-wolf control government was elected that refused to endorse the plan. While the government gave various reasons for not ratifying the plan, more and more diverse interest groups came out in support for both the plan and the process that created it. Eventually, overwhelming public support forced the government to sign and implement the plan as written. This demonstrates that, while it is important for a team to seek the sanction of decision-makers, it is perhaps even more important for the general public to see the effort and the final agreement as fair. Strong support from a broad spectrum of the public can help win the necessary political support.In addition to discussing the unorthodox aspects of this consensus-building effort, this article also attempts to give the reader a front row seat to this process by using the informants' own words—words rich in detail, brimming with color and spoken straight from the heart. Certainly their experience dispels any notion that such efforts are simply a matter of following a recipe. During the process, members of the negotiating team experienced the entire gamut of emotions—anger, defeat, humor and, finally, a genuine sense of pride. As team member Patty Denison put it, “We showed that a random group of people could work together and do something truly monumental.” 相似文献
676.
哈密地区新型建筑材料天然放射性核素含量及居民受照剂量估算 总被引:1,自引:0,他引:1
用放射化学分析方法对哈密地区主要新型建材中^226Ra、^232Th、^40K含量分析测定。结果表明,放射性核素比活度限制值内照射指数和外照射指数平均范围值分别为0.02-0.26,0.03-0.66。花岗岩石材和涂釉制品最高,装饰材料最低。建材所致居民内、外照射年有效剂量当量为0.06-0.96mSv.a^-1,明显低于哈密地区室内环境γ辐射及氡子体所致居民年有效剂量当量实际调查值1.43mSv 相似文献
677.
Jordan faces stringent energy challenges mainly in the form of import dependence and escalating demand. The building sector accounts for 58% of total national electricity consumption and therefore plays an important role in addressing these challenges. This article investigates how energy efficiency in green buildings certified by the Leadership in Energy and Environmental Design (LEED) rating system contribute towards achieving United Nations (UN) Sustainable Development Goals (SDGs) in Jordan. Furthermore, this paper proposes a new Comprehensive Contribution to Sustainable Development Index (CCSDI) to assess the contributions of implementation of the LEED 2009 prerequisites and credits in the Energy and Atmosphere (EA) category to achieve UN SDGs in Jordan. Questionnaire surveys were conducted to obtain data. Relative Importance Index (RII) method was used to evaluate the contributions of LEED 2009 prerequisites and credits in the EA category. Results indicate a positive relationship between the LEED 2009 prerequisites and credits in category and UN SDGs 7?9 and 12?13. We conclude that our proposed CCSDI is a robust tool for assessing the contribution of energy efficiency in LEED 2009 certified green buildings towards achieving UN SDGs in Jordan. 相似文献
678.
为了解决旧工业建筑再生利用施工风险难以快速应对以及特征属性数据缺失的问题,通过对近年历史案例的收集,将规则推理(RBR)引入案例推理(CBR)中,构建旧工业建筑再生利用施工风险应急管理模型。利用组合权重的方法,求出各特征属性的权值;通过计算结构相似度来处理缺失的属性数据,并结合特征属性相似度,求出全局相似度,检索出相似度最大的案例;通过RBR对检索案例的应对措施进行适用性修正,提高应对措施的针对性;最后,选取案例对模型进行应用说明,结果表明:模型具有较强的适用性,可用于旧工业建筑再生利用施工阶段的风险应急管理。 相似文献
679.
采用姐妹染色单体交换方法,对黄浦江水提取物进行体外试验。结果表明,0.02ml/10ml浓度组各点水样的姐妹染色单体交换率,除上游竖僚泾和松浦大桥点外,下游各点及自来水均高于溶剂对照:0.02ml/10ml浓度组除竖僚泾点外,下游各点均高于溶剂对照。两种浓度均显示越往沿江下游,姐妹染色单体交换率越有增高趋势:0.03、0.04(ml/10ml)两个浓度组损害淋巴细胞。 相似文献
680.