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741.
Ecological restoration (ER) of coastal wetlands is extremely important because they provide a huge variety of ecosystem services (ES), but they are the most degraded ecosystems in the world. However, coastal wetlands are usually located in largely modified and densely populated landscapes. Hence their restoration may conflict with cultural values. Therefore, considering the cultural dimension of ER is a way of increasing public acceptance of restoration projects. In this study, we assessed the public acceptance of a restoration project in a coastal wetland of Costa Brava (Spain). We combined the ES framework with a cultural approach, which is capable of considering interdisciplinarity, introducing barely assessed services like tranquility and facilitating further integration of the human dimension in the ES framework. We administered an open‐ended questionnaire to 232 visitors and the answers were submitted to a content analysis to get a post hoc classification of services and values. Our results show that visitors undervalue environmental values, while tranquility is the most commonly stated value. Moreover, place attachment is found to be the main driver to influence the perception of the ER. The study concluded that the project enjoys a high public acceptance. However, some disengagement exists between the goals of restoration and visitors’ perceptions, and this needs to be addressed. Sharing the decision‐making power with stakeholders and informing visitors about ES that are not easily perceived could be appropriate steps to take. 相似文献
742.
Xaysackda Vilaysouk Heinz Schandl Shinsuke Murakami 《Journal of Industrial Ecology》2019,23(3):649-662
Modern environmental and sustainability policy that acknowledges the linkages between socioeconomic processes and environmental pressures and impacts, and designs policies to decouple economic activity from environmental pressures and impacts, requires a sophisticated and comprehensive knowledge base. The concept of industrial metabolism provides a sound conceptual base, and material flow accounting—including primary material inputs and outflows of waste and emissions—provides a well‐accepted operationalization. Studies presenting a comprehensive material flow account for a national economy are rare, especially for developing countries. Countries such as Lao People's Democratic Republic (Lao PDR or Laos) face dual objectives of improving the material standard of living of their people while managing natural resources sustainably and mitigating adverse environmental impacts from growing resource throughput. Our research fills a knowledge gap, presents a comprehensive account of material inputs and outflows of waste and emissions for the Lao PDR national economy, and applies the accounting approach for a low‐income economy in Asia. We present a material balance for the years 2000 and 2015. For this research, we used data from Lao PDR national statistics and the accounting guidelines of the European Statistical Office (Eurostat), which pioneered the use of material flow data as part of its official statistical reporting. We demonstrate the feasibility of the accounting approach and discuss the robustness of results using uncertainty analysis conducted with statistical approaches commonly used in the field of industrial ecology, including Gauss's law of error propagation and Monte Carlo simulation. We find that the fast‐changing scale and composition of Lao PDR material flows, waste, and emissions presents challenges to the existing policy capacity and will require investment into governance of changed patterns of material use, waste disposal, and emissions. We consider the data analysis sufficiently robust to inform such a change in policy direction. 相似文献
743.
【目的】为了明确食物颜色对不同日龄昆虫体色的影响,并推广利用计算机视觉研究昆虫体色的技术。【方法】本研究以斜纹夜蛾Prodenia litura幼虫为实验材料,采用计算机定量分析的方法,对取食不同颜色型人工饲料的斜纹夜蛾幼虫头部、胸部斑纹、胸腹部和背中线的红色(R)、绿色(G)、蓝色(B)和明度(L)值进行了定量化分析。【结果】结果表明:幼虫的斑纹、胸腹部背面及侧面主色和背中线的R,G,B和L值随日龄增加而下降;头部R,G,B和L值在1-3日龄增加,后随日龄的增加而下降。幼虫体色变化也受食物颜色的影响,以对1-7日龄的影响为最大;红色型食物r∶g∶b=(128~251)∶(3~129)∶(6~96)对幼虫各部位体色的影响大于黄色、绿色和紫色的食物;幼虫取食不同颜色型食物后,各部位的变异系数大小依次为:斑纹胸腹部头部背中线。最后,建立了幼虫体色与食物色彩r,g,b值及日龄的回归方程。【结论】斜纹夜蛾幼虫体色受到食物颜色的影响,且在低龄时更为显著。 相似文献
744.
745.
Linking macrotrends and microrates: Re‐evaluating microevolutionary support for Cope's rule 下载免费PDF全文
Kiyoko M. Gotanda Cristián Correa Martin M. Turcotte Gregor Rolshausen Andrew P. Hendry 《Evolution; international journal of organic evolution》2015,69(5):1345-1354
Cope's rule, wherein a lineage increases in body size through time, was originally motivated by macroevolutionary patterns observed in the fossil record. More recently, some authors have argued that evidence exists for generally positive selection on individual body size in contemporary populations, providing a microevolutionary mechanism for Cope's rule. If larger body size confers individual fitness advantages as the selection estimates suggest, thereby explaining Cope's rule, then body size should increase over microevolutionary time scales. We test this corollary by assembling a large database of studies reporting changes in phenotypic body size through time in contemporary populations, as well as studies reporting average breeding values for body size through time. Trends in body size were quite variable with an absence of any general trend, and many populations trended toward smaller body sizes. Although selection estimates can be interpreted to support Cope's rule, our results suggest that actual rates of phenotypic change for body size cannot. We discuss potential reasons for this discrepancy and its implications for the understanding of Cope's rule. 相似文献
746.
Enantioseparation of the Six Important Intermediates of Homoharringtonine With Immobilized Cellulose Chiral Stationary Phase 下载免费PDF全文
A new liquid chromatographic method has been developed for the chiral separation of the enantiomers of intermediates in the preparation of the ester side‐chain of homoharringtonine. The enantiomers were separated by a Chiralpak IC (250 × 4.6 mm, 5 µm) in normal phase high‐performance liquid chromatography (HPLC). Four compounds were baseline resolved. By comparing the chromatographs of racemates and single enantiomers of the six intermediates, the enantiomeric excess values of the single enantiomers were evaluated, and the elution orders of the enantiomers were established. Chirality 27:538–542, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
747.
贵州野生小檗科木本植物的园林观赏特性及用途 总被引:2,自引:0,他引:2
通过调查及查阅有关资料,对贵州省野生小檗科木本植物45种1变种的观赏生物学特性进行了研究,并叙述了这些观赏植物的园林用途。 相似文献
748.
In their ambitious Evolutionary Anthropology paper, Winterhalder and Smith 1 review the history, theory, and methods of human behavioral ecology (HBE). In establishing how HBE differs from traditional approaches within sociocultural anthropology, they and others laud its hypothetical‐deductive research method. 1 - 3 Our aim is to critically examine how human behavioral ecologists conduct their research, specifically how they analyze and interpret data as evidence for scientific hypotheses. Through computer simulations and a review of empirical studies of human sex ratios, we consider some limitations of the status quo and present alternatives that could strengthen the field. In particular, we suggest that because human behavioral ecologists often consider multiple hypotheses, they should use statistical approaches that can quantify the evidence in empirical data for competing hypotheses. Although we focus on HBE, the principles of this paper apply broadly within biological anthropology. 相似文献
749.
AIMS: To determine the levels of measurement uncertainty (MU) obtained in proficiency testing and routine microbiological analyses of foods and to compare these with estimates of MU obtained for results of analyses obtained in collaborative interlaboratory studies of microbiological methods. METHODS AND RESULTS: Raw data submitted by participants in the Food Examination Proficiency Assessment Scheme were obtained from the Central Science Laboratory (York). Internal quality monitoring data were obtained from Health Protection Agency (HPA) laboratories, together with data from routine food examinations undertaken in HPA laboratories. The data sets were analysed to determine the relative standard deviations of reproducibility (RSD(R)), based on log(10) colony count values, and thence the relative measures of expanded uncertainty. Analysis of proficiency test data showed extreme values of RSD(R) up to +/-30% depending upon the organism, the laboratory and the method of examination. RSD(R) values on routine samples averaged around +/-12% but ranged up to +/-41% in a few instances. Internal quality assessments for different organisms ranged up to +/-27%, depending upon the particular organism and examination procedure. The results show little difference in uncertainty for counts obtained using different plating systems (e.g. pour plates, spread plates or spiral plating) on the same dilutions of the same food samples. The data are compared with estimates of microbiological uncertainty derived in interlaboratory studies. CONCLUSIONS: The estimates of uncertainty ranged widely, both within and between laboratories, and appeared to bear little relationship to the foodstuff under examination. The extent of MU associated with many routine microbiological examinations is generally no worse than those produced in inter-laboratory trials, although notable exceptions were seen. SIGNIFICANCE AND IMPACT OF THE STUDY: Knowledge of the levels of MU may have wide impact on the establishment of international standard methods for microbiological examination of foods and the ability to set realistic microbiological criteria. 相似文献
750.
The latest crystallographic model of the cyanobacterial photosystem II (PS II) core complex added one transmembrane low molecular weight (LMW) component to the previous model, suggesting the presence of an unknown transmembrane LMW component in PS II. We have investigated the polypeptide composition in highly purified intact PS II core complexes from Thermosynechococcus elongatus, the species which yielded the PS II crystallographic models described above, to identify the unknown component. Using an electrophoresis system specialized for separation of LMW hydrophobic proteins, a novel protein of ∼ 5 kDa was identified as a PS II component. Its N-terminal amino acid sequence was identical to that of Ycf12. The corresponding gene is known as one of the ycf (hypothetical chloroplast reading frame) genes, ycf12, and is widely conserved in chloroplast and cyanobacterial genomes. Nonetheless, the localization and function of the gene product have never been assigned. Our finding shows, for the first time, that ycf12 is actually expressed as a component of the PS II complex in the cell, revealing that a previously unidentified transmembrane protein exists in the PS II core complex. 相似文献