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1.
The terrestrial New Zealand fauna has developed on an ancient landmass of continental origins that has had an increasingly isolated existence since the late Mesozoic. As a continental remnant, New Zealand harbours survivors of many ancient lineages many of which were once far more widely distributed. But New Zealand's fauna also resembles that of an isolated archipelago: many higher taxa are missing; some have undergone extensive radiations in situ; and levels of endemism approach 100% in many groups. Ecologically, the fauna is characterized by frequent niche shifts, gigantism, and extended life histories with low reproductive rates, factors that make many species vulnerable to human disturbance. Data continue to amass supporting the ecophysiological as well as phylogenetic distinctiveness of the fauna. Described taxonomic diversity, even of terrestrial vertebrates, continues to increase.  相似文献   

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Purpose

Life cycle assessment (LCA) practitioners face many challenges in their efforts to describe, share, review, and revise their product system models, and to reproduce the models and results of others. Current life cycle inventory modeling techniques have weaknesses in the areas of describing model structure, documenting the use of proxy or non-ideal data, specifying allocation, and including modeler’s observations and assumptions—all affecting how the study is interpreted and limiting the reuse of models. Moreover, LCA software systems manage modeling information in different and sometimes non-compatible ways. Practitioners must also deal with licensing, privacy/confidentiality of data, and other issues around data access which impact how a model can be shared.

Methods

This letter was prepared by a working group of the North American Life Cycle Assessment Advisory Group to support the UNEP-SETAC Life Cycle Initiative’s Flagship Activity on Data, Methods, and Product Sustainability Information. The aim of the working group is to define a roadmap of the technical advances needed to achieve easier LCA model sharing and improve replicability of LCA results among different users in a way that is independent of the LCA software used to compute the results and does not infringe on any licensing restrictions or confidentiality requirements. This is intended to be a consensus document providing the state of the art in this area, with milestones for research and implementation needed to resolve current issues.

Results and Conclusions

The roadmap identifies fifteen milestones in three areas: “describing model contents,” “describing model structure,” and “collaborative use of models.” The milestones should support researchers and software developers in advancing practitioners’ abilities to share and review product system models.
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The annual processing of citrus fruit wastes in the United States has reached two million tons. Forty thousand tons of pectin could be produced, compared with current production of three thousand tons. The physical and chemical properties of pectic substances are important botanically and industrially. Pectic substances aid in maintaining texture of fruits and vegetables and serve as jellying agents in preserves. The availability of increasing amounts of citrus wastes, combined with improvements in manufacturing techniques and new uses, promises expansion of industries concerned with pectin production and utilization.  相似文献   

4.
The development of design systems which ensure economic feasibility has been the focus of recent research in the manufacturing area. Traditional design and justification approaches have been cited as having shortcomings; thus, there have been a variety of modifications and enhancements developed. An approach that is conceptually different from the traditional approaches seeks the integration of the economic analysis within the design process. We denote this approach as thedesign justification method. This paper reviews literature related to the explicit and implicit integration of economic factors in the manufacturing system design process, followed by supporting issues for the implementation of the design justification concept.  相似文献   

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A great deal of progress has been made in understanding both the structure and the mechanism of F1-ATPase. The primary structure is now fully known for at least five species. Sequence comparison between chloroplast, photobacteria, aerobic bacteria, and mitochondrial representatives allow us to infer more general functional relationships and evolutionary trends. Although the F1 moiety is the most studied segment of the H+-ATPase complex, there is not a full understanding of the mechanism and regulation of its hydrolytic activity. The subunit is now known to contain one and probably two nucleotide binding domains, one of which is believed to be a catalytic site. Recently, two similar models have been proposed to attempt to describe the active part of the subunits. These models are mainly an attempt to use the structure of adenylate kinase to represent a more general working model for nucleotide binding phosphotransferases. Labelling experiments seem to indicate that several critical residues outside the region described by the adenylate kinase part of this model are also actively involved in the ATPase activity. New models will have to be introduced to include these regions. Finally, it seems that a consensus has been reached with regard to a broad acceptance of the asymmetric structure of the F1-moiety. In addition, recent experimental evidence points toward the presence of nonequivalent subunits to describe the functional activity of the F1-ATPase. A summary diagram of the conformational and binding states of the enzyme including the nonequivalent subunit is presented. Additional research is essential to establish the role of the minor subunits—and of the asymmetry they introduce in F1—on the physiological function of the enzyme.  相似文献   

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《新西兰生态学杂志》2011,33(2):190-204
Most non-native weeds and other naturalised plants are in the early stages of invasion into New Zealand landscapes. For this invasion to be controlled, even partially, it is important to understand the dominant routes, mechanisms, and rates of weed spread across landscapes. With their linear corridors of disturbed habitats, roadsides are thought to play a large role in the spread of some weeds. We used both new surveys and existing data to assess which of the 328 environmental weeds listed by the Department of Conservation are most frequently found and where on roadsides, and whether distribution patterns are consistent with linear dispersal. We also analysed historical survey data for relationships between reserve weediness and proximity to roads. We surveyed 340 plots of 100-m-long stretches of roadside across four regions and found between 2 and 19 environmental weeds per plot; 128 species in total (Chao estimate 148). Especially abundant were agricultural (weeds and cultivated) species, species that have been naturalised for well over 50 years, and species that disperse externally attached to vertebrates. While we purposefully sampled within 10 km of town limits, we found no strong effect of distance from town on roadside weed richness, including richness of just ornamentally sourced weeds. Instead, number of houses within 250?m and presence of an adjacent house or other residential structure were both important, as was presence of woody vegetation on and adjacent to roadsides. Reserves adjacent to roads had significantly higher weed richness than reserves further from roads, although the causal mechanisms are unclear. Our results suggest that while roadsides include suitable habitats for most environmental weeds, distributions are patchy and roads show little sign of acting as linear dispersal corridors, instead they largely reflect neighbouring land uses. As such, roadside weeds should best be managed as part of the wider landscape.  相似文献   

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Purpose

We present experiences and reflections from social life cycle assessment (S-LCA) case study, the aim of which was to identify social hotspots, test and evaluate the methodology and propose improvements. This paper discusses the usability and applicability of the methodology used based on our experiences from the study. The main issues considered are whether the gathering of data and other information is feasible and straightforward to perform, whether the method provides added value and relevant results and how these can be presented.

Method

We have conducted a generic hotspot assessment on a laptop computer according to the Guidelines for Social Life Cycle Assessment of Products (Benoît and Mazijn 2009). The experiences presented were gathered throughout the case study. The supply chain of the laptop was simplified, and we focused on a limited number of materials. The impacts were assessed in relation to the area of protection on human well-being and to affected stakeholders. Social impacts from the actual use of the product were not included. Methodological sheets were used for guidance on inventory indicators and data sources for data collection. Country-specific data were collected and entered into a spreadsheet. The process has been guided by regular meetings in a reference group, composed of representatives of all stakeholder groups.

Results and discussion

The data collection process was impaired by a lack of data and low data quality. In order to relate the data collected to the product assessed, each country's share of the activity performed in each phase was determined, and the activity percentage was calculated. In order to consider and relate all the phases in the product system, we used an estimated activity variable due to the lack of data. We developed a new approach to impact assessment. By determining the combination of the most extensive activity, as well as the most negative in the range of possible values for involved countries, we identified the hotspots. The results were not further aggregated in order to promote transparency.

Conclusions

We found the S-LCA methodology to be feasible and useful. By handling all relevant issues within one study using a systems perspective on the product life cycle, knowledge can be gained. However, there are still some major challenges. The definition of relevant indicators, data availability, impact pathways, activity variables, results presentation and possible aggregation, the handling of stakeholder context and the restricted assessment of the use phase were identified as major issues to deal with in further studies. Communication, and hence use of the results, is a crucial issue to enable the outcome of a study to result in actions that actually improve human well-being.  相似文献   

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New Zealanders (n = 354) rated the acceptability of lethal and nonlethal cat control methods and the importance of conservation and welfare. Lethal control was more acceptable for feral cats than strays; for nonlethal control, the inverse was true. More than concern for the welfare of cats subjected to control, perceived conservation benefits, risk of disease transfer, and companion cat welfare dictated the acceptability of control measures. Similarly, the welfare consideration for groups of cats differed, transitioning from companion (highest) to feral (lowest). Differences in attitudes toward acceptability of control methods were evident. In particular, nonhuman animal professionals ranked lethal control as more acceptable than did nonanimal professionals. Cat caregivers (owners) considered both conservation and welfare issues of greater importance than did nonowners. Owners ranked the acceptability of nonlethal control methods higher for stray cats, but not feral, than did nonowners. This research indicates that the use of the terms stray and feral may have significant impact on cats in New Zealand. There is also a greater consideration of conservation values than of welfare in stray and feral cat control.  相似文献   

13.
We describe here Sursumura affinis sp.n., a new deepwater species of the family Munnopsididae (Isopoda: Asellota) from the South Australian and South Fiji hollows. It is characterized as follows: the dorsum of the body is not granulated, bearing short setae; the pleonite lacks a dorsal spine; the pleotelson bears 5 dorsal spines; the preanal projection of the pleotelson is well-developed; the exopod of pleopod 4 is relatively slender and short. In morphology, the new species is most similar to S. abyssalis (Wolff, 1962) from the Tasmanian Sea. This is the second species of the genus described from the Australian–New Zealand region.  相似文献   

14.
Aromatase is an enzyme required for the conversion of androgens to estrogens. Estrogens are female sex hormones involved in the development and growth of breast tumors. It has been of significant interest to investigate the structure–function relationship of aromatase since its inhibitors have shown great promise in fighting breast cancer. Aromatase belongs to the cytochrome P450 family, and forms an electron-transfer complex with its partner, NADPH-cytochrome P450 reductase (CPR), during the aromatization reaction. Aromatase is found to be widely expressed in vertebrates with unique substrates androstenedione and testosterone, but with various catalytic capacities reflecting species differences in Km, Vmax, etc. This report will summarize current progress in sequence–function correlation analysis of the aromatase protein family and molecular characterization of the interaction between aromatase and CPR. These studies may lead to a novel field for the development of new inhibitors which interfere with the interaction between aromatase and CPR in order to inhibit the aromatization reaction.  相似文献   

15.
《新西兰生态学杂志》2011,34(1):175-184
This paper briefly reviews advances in knowledge of the non-lichenised fungi of New Zealand over the past 25 years. Since 1980, the number of species recorded from New Zealand has doubled, and molecular techniques have revolutionised studies on fungal phylogeny and our understanding of fungal distribution, biology and origins. The origins of New Zealand?s fungi are diverse; a few appear to be ancient, whereas many have arrived in geologically more recent times following trans-oceanic dispersal. Some of these more recent arrivals have evolved subsequently to form local endemic species, while others may be part of larger populations maintained through regular, trans-oceanic gene flow. Although questions remain about which fungi truly are indigenous and which are exotic, about one-third of the fungi recorded from New Zealand are likely to have been introduced since human settlement. While most exotic species are confined to human-modified habitats, there are some exceptions. These include species with potential to have significant impacts at the landscape scale. Examples from saprobic, pathogenic, endophytic and ectomycorrhizal fungi are used to discuss the factors driving the distribution and dispersal of New Zealand?s fungi at both global and local scales, the impact that historical changes to New Zealand?s vascular plant and animal biota have had on indigenous fungi, and the broader ecological impact of some of the exotic fungal species that have become naturalised in native habitats. The kinds of fungi present in New Zealand, and the factors driving the distribution and behaviour of those fungi, are constantly changing. These changes have occurred over a wide scale, in both time and space, which means New Zealand?s indigenous fungi evolved in response to ecological pressures very different from those found in New Zealand today.  相似文献   

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The International Journal of Life Cycle Assessment - This paper aims to investigate the common understanding of the variety of simplifications in LCA, by reviewing what simplification approaches...  相似文献   

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Tagua is the hard seed of a South American palm tree, highly valued for manufacture into buttons and other small articles requiring a hard, easily cut, lustrous material.  相似文献   

20.
Abstract

The following weevil species are known from The Snares islands: Anthribidae — Cacephatus aucklandicus, Lichenobius littoralis; Curculionidae — Exeiratus laqueorum, Pentarthrum spadiceum, Notacalles planidorsis, Lyperobius sp., Hadramphus stilbocarpae, Phrynixus laqueorum, Gromilus laqueorum, Nestrius laqueorum, Catoptes brevicornis australis, Oclandius vestitus. The larvae and pupae are described and figured, and keys for their separation are given.  相似文献   

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