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11.
EIA plays an important role in enhancing the environmental performance of the construction sector. In recent years, the construction sector has been developing green procurement practices. Green procurement is a process that involves the incorporation of environmental requirements during the procurement of services and products. However, discussion on green procurement is rarely seen during the EIA phase. This paper addresses possible opportunities for improving the coordination between EIA and green procurement within the construction sector. The linking of EIA and green procurement has been postulated in the paper as an aid to strengthen the coordination between project planning and implementation. The paper is based on a literature review and is an outcome of an on-going research project concerning EIA and green procurement. This study indicated that it would be appropriate to introduce green procurement during the pre-decision phase of an EIA. In the present study, the opportunities for integrating green procurement at the stage of EIA are associated with the integration of project planning and EIA. Future research should investigate the mechanism through which the link can be established.  相似文献   
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The occurrence of male pregnancy in the family Syngnathidae (seahorses, pipefishes, and sea dragons) provides an exceptionally fertile system in which to investigate issues related to the evolution of parental care. Here, we take advantage of this unique reproductive system to study the influence of maternal body size on embryo survivorship in the brood pouches of pregnant males of the broad-nosed pipefish, Syngnathus typhle. Males were mated with either two large females, two small females, a large then a small female, or a small then a large female. Our results show that offspring survivorship depends on an interaction between female body size and the number of eggs transferred by the female. Eggs of larger females deposited in large numbers are more likely to result in viable offspring than eggs of smaller females laid in large numbers. However, when females deposited smaller numbers of eggs, the eggs from smaller females were more likely to produce viable offspring compared to those from larger females. We found no evidence that this result was based on mating order, the relative sizes of competing females, or egg characteristics such as dry weight of eggs. Additionally, male body size did not significantly influence the survivorship of offspring during brooding. Our results suggest that the factors underlying offspring survivorship in pipefish may be more complex than previously believed, with multiple factors interacting to determine the fitness of individual offspring within the broods of pregnant males.  相似文献   
14.
Brood guarding animals face many critical trade-offs. Sand goby males (Pomatoschistus minutus) build nests with larger openings during low oxygen conditions, presumably to enhance ventilation. However, this may make the nest easier for egg predators to detect and harder for guarding males to defend. Manipulating oxygen level and predator presence (a small crab) for small and large males, we found support for a parental trade-off between fanning and nest defense. An increased fanning activity resulted in less time for guarding. Small males and males in low oxygen showed a higher fanning expenditure than large males and males in high oxygen, but surprisingly, filial cannibalism did not differ between these groups. Males built larger nest openings in low than high oxygen. However, males in both high and low oxygen treatments reduced their nest opening size in the presence of a predator, again indicating an important trade-off between ventilation and nest defense.  相似文献   
15.
One of ABB Atom's methods, ELDECON, is an electrochemical process for decontamination of components used in nuclear power plants. ELDECON removes radioactive species while producing small amounts of waste. However, the waste sludge that is produced in the ELDECON process contains chrornate (Cr(VI)). According to the US Cod of Feguration, 40 CFR 261, if a process in any step creates chromate, the final waste has to be tested in a toxicity characteristic leachate procedure. In order to pass the test, the chromate has to be reduced to chromium (Cr(III)). Electrochemistry has proven to be a valuable tool. When incorporating indirect electrolysis into the ELDECON concept, the chromate ions are reduced. This is done by the use of an electrochemical cell (reactor bed). The method involves ferric nitrate as a reagent which, besides converting the chromate completely, also decreases the reaction time. The reaction time and the amount of solution treated in the cell have a close to linear relationship (i.e. the reaction time is proportional to the amount of solution). This makes the test cell feasible to scale up and use in the industry.  相似文献   
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Tonderski KS  Arheimer B  Pers CB 《Ambio》2005,34(7):544-551
In southern Sweden, wetlands are constructed to remove nitrogen (N) in agricultural catchments. The possible effects of such wetlands on riverine phosphorus (P) were also estimated using input-output data from three well-monitored wetlands. This was done to formulate a simple model for removal of P that is dependent on inflow characteristics. Next, the N- and P-reducing effects of wetlands were modeled on a catchment scale (1900 km2) using the HBV-NP model and various assumptions about the wetland area and location. All three wetlands functioned as sinks for total P (tot-P) and for total suspended solids (TSS) with a removal of 10% to 31% and 28% to 50%, respectively. Mean P-removal rates of 17-49 kg ha(-1) yr(-1) were well simulated with the model. Catchment scale simulations indicated that wetlands were more efficient (in percentage of load) as traps for P than for N and that this may motivate the construction of wetlands for P removal far upstream from the catchment outlet.  相似文献   
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The last several decades of research in behavioral ecology have resulted in a deeper appreciation of post-mating processes and sexual conflict in sexual selection. One of the most controversial aspects of sexual selection is cryptic mate choice. Here, we take advantage of male pregnancy in a sex-role-reversed pipefish (Syngnathus typhle) to quantify cryptic choice based on perceived parasite load and other sources of variance in female fitness. Studies have shown that S. typhle males preferentially mate with females with lower parasite loads and that a male’s perception of female parasite load can be altered by tattooing females. We manipulated the apparent parasite load of females in controlled mating experiments to test the hypothesis that post-copulatory sexual selection is dependent on a male’s perception of female parasite load in pipefish. Our results provided no evidence for cryptic male choice based on perceived female parasite load. However, we found evidence that eggs from larger females were more likely to result in viable offspring than eggs from smaller females and that the first female to mate with a male transferred more eggs per copulation on average. Overall, our results show that potential for post-copulatory sexual selection does exist in pipefish, but the male’s perception of female parasite load does not play a major role in this process.  相似文献   
18.
在富营养化湖泊开展了生物化学湖泊模型(BIOLA)对不同富营养化管理行动的响应研究.此项研究中的管理行动包括减少营养物质载荷量、沉积物控制、生物控制,以及使用除草剂等.该模型用于模拟上世纪90年代湖泊中营养物和生物量浓度.另外,对同一时期的管理情景也进行了模拟.通过对几个生态参数校准,来更好地模拟所选定湖泊的行为,但对磷酸盐的模拟仍存在一些问题.这表明需要对模型做进一步的开发.在营养物质载荷量减少和通过降低食草鱼类的数量进行生物控制情景下,该湖泊出现了良好的发展态势.同时减少氮和磷的载荷量比仅仅减少其中一种成分的载荷量对湖泊水质有更大的影响.  相似文献   
19.
本文所讨论的内容是当设计一个新的动物图舍系统时或者对现有的圈舍系统进行改造时,如何使动物们先天所具有的自然行为得以继续传承和保留.自然行为的定义是;动物处于自然环境中所表现出的由进化而产生的不同行为方式的总称.自然行为的两个很重要的方面是动机和先天的行为,抑制这两个方面会造成动物异常的行为和压力.人们首先应对野生或半自然环境中特定物种动物的行为有一个基本的了解.然后,在养殖空间压缩的情况下,发现动物正常行为的关键激励因素及关键特征,构成圈舍,进行科学测试和  相似文献   
20.
Climate change impact on water quality: model results from southern Sweden   总被引:4,自引:0,他引:4  
Starting from six regional climate change scenarios, nitrogen leaching from arable-soil, water discharge, and nitrogen retention was modeled in the R?nne? catchment. Additionally, biological response was modeled in the eutrophic Lake Ringsj?n. The results are compared with similar studies on other catchments. All scenarios gave similar impact on water quality but varied in quantities. However, one scenario resulted in a different transport pattern due to less-pronounced seasonal variations in the hydrology. On average, the study shows that, in a future climate, we might expect: i) increased concentrations of nitrogen in the arable root zone (+50%) and in the river (+13%); ii) increased annual load of nitrogen from land to sea (+22%) due to more pronounced winter high flow; moreover, remote areas in the catchment may start to contribute to the outlet load; iii) radical changes in lake biochemistry with increased concentrations of total phosphorus (+50%), total nitrogen (+20%), and planktonic algae such as cyanobacteria (+80%).  相似文献   
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