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1.
J. M. R. Hughes 《Plant Ecology》1995,118(1-2):17-28
The status of wetland inventory and classification is considered for 44 European countries, as well as for the continent as a whole. Data and information were obtained from questionnaires compiled by the International Waterfowl and Wetland Research Bureau, the MedWet sub-project on inventory and monitoring, and the Ramsar Bureau. Nine European countries have national wetland inventories, and 32 have inventories of sites of international importance listed under the Ramsar Convention. There has been a trend in producing regional or continental inventories for wetlands that are important as waterfowl habitat. There is an urgent need to produce wetland inventories for all European countries. The Ramsar database takes into consideration hydrological and economic wetland values, as well as ecological ones. The Ramsar classification lists a total of 35 wetland types, and is sufficiently flexible that it could be used for classifying European wetlands at the national scale. 相似文献
2.
Julen Astigarraga Enrique Andivia Miguel A. Zavala Antonio Gazol Vernica Cruz‐Alonso Sergio M. Vicente‐Serrano Paloma Ruiz‐Benito 《Global Change Biology》2020,26(9):5063-5076
Climate and forest structure are considered major drivers of forest demography and productivity. However, recent evidence suggests that the relationships between climate and tree growth are generally non‐stationary (i.e. non‐time stable), and it remains uncertain whether the relationships between climate, forest structure, demography and productivity are stationary or are being altered by recent climatic and structural changes. Here we analysed three surveys from the Spanish Forest Inventory covering c. 30 years of information and we applied mixed and structural equation models to assess temporal trends in forest structure (stand density, basal area, tree size and tree size inequality), forest demography (ingrowth, growth and mortality) and above‐ground forest productivity. We also quantified whether the interactive effects of climate and forest structure on forest demography and above‐ground forest productivity were stationary over two consecutive time periods. Since the 1980s, density, basal area and tree size increased in Iberian forests, and tree size inequality decreased. In addition, we observed reductions in ingrowth and growth, and increases in mortality. Initial forest structure and water availability mainly modulated the temporal trends in forest structure and demography. The magnitude and direction of the interactive effects of climate and forest structure on forest demography changed over the two time periods analysed indicating non‐stationary relationships between climate, forest structure and demography. Above‐ground forest productivity increased due to a positive balance between ingrowth, growth and mortality. Despite increasing productivity over time, we observed an aggravation of the negative effects of climate change and increased competition on forest demography, reducing ingrowth and growth, and increasing mortality. Interestingly, our results suggest that the negative effects of climate change on forest demography could be ameliorated through forest management, which has profound implications for forest adaptation to climate change. 相似文献
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Roland Hischier Martin Baitz Rolf Bretz Rolf Frischknecht Niels Jungbluth Torsten Marheineke Phil McKeown Michiel Oele Philippe Osset Isa Renner Tim Skone Helena Wessman Angeline S. H. de Beaufort 《The International Journal of Life Cycle Assessment》2001,6(4):192-198
Data availability and data quality are still critical factors for successful LCA work. The SETAC-Europe LCA Working Group
‘Data Availability and Data Quality’ has therefore focused on ongoing developments toward a common data exchange format, public
databases and accepted quality measures to find science-based solutions than can be widely accepted. A necessary prerequisite
for the free flow and exchange of life cycle inventory (LCI) data and the comparability of LCIs is the consistent definition,
nomenclature, and use of inventory parameters. This is the main subject of the subgroup ‘Recommended List of Exchanges’ that
presents its results and findings here:
相似文献
• | Rigid parameter lists for LCIs are not practical; especially, compulsory lists of measurements for all inventories are counterproductive. Instead, practitioners should be obliged to give the rationale for their scientific choice of selected and omitted parameters. The standardized (not: mandatory!) parameter list established by the subgroup can help to facilitate this. |
• | The standardized nomenclature of LCI parameters and the standardized list of measurement bases (units) for these parameters need not be appliedinternally (e.g. in LCA software), but should be adhered to inexternal communications (data for publication and exchange). Deviations need to be clearly stated. |
• | Sum parameters may or may not overlap - misinterpretations in either direction introduce a bias of unknown significance in the subsequent life cycle impact assessments (LCIA). The only person who can discriminate unambiguously is the practitioner who measures or calculates such values. Therefore, a clear statement of independence or overlap is necessary for every sum parameter reported. |
• | Sum parameters should be only used when the group of emissions as such is measured. Individually measured emission parameters should not be hidden in group or sum parameters. |
• | Problematic substances (such as carcinogens, ozone depleting agents and the like) maynever be obscured in group emissions (together with less harmful substances or with substances of different environmental impact), butmust be determined and reported individually, as mentioned in paragraph 3.3 of this article. |
• | Mass and energy balances should be carried out on a unit process level. Mass balances should be done on the level of the entire mass flow in a process as well as on the level of individual chemical elements. |
• | Whenever possible, practitioners should try to fill data gaps with their knowledge of analogous processes, environmental expert judgements, mass balance calculations, worst case assumptions or similar estimation procedures. |
6.
Nay Chi Htun Koichi Miyaki Chenxi Zhao Masaaki Muramatsu Noriko Sato 《Biochemical and biophysical research communications》2014
Higher cognitive performance, maintenance of mental health and psychological well-being require adequate prefrontal cortex (PFC) function. “Inverted U-shaped” dopamine model indicates optimal PFC dopamine level is important to attain its function while high or low levels have adverse effects. Catechol-O-methyltransferase (COMT) and methylenetetrahydrofolate reductase (MTHFR) may be involved in this complex non-linear PFC dopamine regulation. We addressed whether genetic variation reflecting COMT and MTHFR activities can explain the inter-individual mental health differences in healthy Japanese men (n = 188). The mental health was measured by Mental Health Inventory (MHI)-5 score. The rs4633–rs4818–rs4680 haplotypes were used to represent the multilevel COMT activities, while for MTHFR, the functional single polymorphism, rs1801133 (C677T), was used. We examined the effectiveness of haplotype-based association analysis of COMT on mental health together with studying its interaction with MTHFR-C677T. As a result, the relation between activity-ranked COMT genotype and MHI-5 score showed a tendency to fit into an “inverted U-shaped” quadratic curve (P = 0.054). This curvilinear correlation was significant in the subjects with MTHFR-CC (P < 0.001), but not with MTHFR T-allele carriers (P = 0.793). Our pilot study implies a potential influence of COMT and MTHFR genotypic combination on normal variation of mental health. 相似文献
7.
A survey of unresolved problems in life cycle assessment 总被引:2,自引:2,他引:0
John Reap Felipe Roman Scott Duncan Bert Bras 《The International Journal of Life Cycle Assessment》2008,13(4):290-300
Background, aims, and scope Life cycle assessment (LCA) stands as the pre-eminent tool for estimating environmental effects caused by products and processes
from ‘cradle to grave’ or ‘cradle to cradle.’ It exists in multiple forms, claims a growing list of practitioners, and remains
a focus of continuing research. Despite its popularity and codification by organizations such as the International Organization
for Standards and the Society of Environmental Toxicology and Chemistry, life cycle assessment is a tool in need of improvement.
Multiple authors have written about its individual problems, but a unified treatment of the subject is lacking. The following
literature survey gathers and explains issues, problems and problematic decisions currently limiting LCA’s goal and scope
definition and life cycle inventory phases.
Main features The review identifies 15 major problem areas and organizes them by the LCA phases in which each appears. This part of the
review focuses on the first 7 of these problems occurring during the goal and scope definition and life cycle inventory phases.
It is meant as a concise summary for practitioners interested in methodological limitations which might degrade the accuracy
of their assessments. For new researchers, it provides an overview of pertinent problem areas toward which they might wish
to direct their research efforts.
Results and discussion Multiple problems occur in each of LCA’s four phases and reduce the accuracy of this tool. Considering problem severity and
the adequacy of current solutions, six of the 15 discussed problems are of paramount importance. In LCA’s first two phases,
functional unit definition, boundary selection, and allocation are critical problems requiring particular attention.
Conclusions and recommendations Problems encountered during goal and scope definition arise from decisions about inclusion and exclusion while those in inventory
analysis involve flows and transformations. Foundational decisions about the basis of comparison (functional unit), bounds
of the study, and physical relationships between included processes largely dictate the representativeness and, therefore,
the value of an LCA. It is for this reason that problems in functional unit definition, boundary selection, and allocation
are the most critical examined in the first part of this review.
相似文献
Bert BrasEmail: |
8.
Abstract. Reproducibility of vegetation measurements is critical for large‐scale or long‐term studies, where numerous observers collect data, but past studies have questioned repro‐ducibility of some techniques. Five methods of evaluating understory composition were appraised for reproducibility among six observers in two forest types in south‐central Alaska: ocular estimates in quadrats, overall community species rank and cover estimates, nested rooted frequency, horizontal‐vertical profiles, and pin drop (systematic points). One forest type was selected to represent structure of coastal communities, another to represent structure of interior Alaska communities. Three general methods of evaluating reproducibility were considered: standard deviations (precision among observers), components of variance (percentage of total variance attributable to observers), and analysis of variance (significance of observer variance). Observer variances were generally similar among techniques and significant in most cases. No technique stood out as being more reproducible than others. Features of techniques other than reproducibility may be more important when selecting a technique. Management decisions based on vegetation cover data should consider the observer errors involved as well as biological significance. 相似文献
9.
France Bellisle Karine Clment Michelle Le Barzic Annie Le Gall Bernard Guy‐Grand Arnaud Basdevant 《Obesity (Silver Spring, Md.)》2004,12(12):2023-2030
Objective: To examine how chronic dietary restraint, disinhibition, and hunger, as assessed by the Eating Inventory, vary over a broad range of BMI values from leanness to massive obesity, in subjects with family obesity. Eating Inventory factors were also studied as a function of personal weight history. Research Methods and Procedures: Subjects were 2509 participants in a genetic study of obesity. BMIs ranged from 15 to 87 kg/m2. Six BMI groups were formed (<27, 27 to 30, 30 to 35, 35 to 40, 40 to 45, and >45). Results: Multivariate analyses showed that restraint and disinhibition were significantly associated with BMI in men, whereas only disinhibition was in women. Disinhibition scores correlated strongly with hunger scores in both genders in all BMI categories; dietary restraint tended to correlate with the other two factors positively in leaner subjects and negatively in the highest BMI categories. Highly restrained normal‐weight subjects were likely to exhibit disinhibition and hunger, whereas massively obese persons with very high disinhibition scores showed high hunger but little restraint. The highest restraint scores were observed in nonobese adult women with previous obesity in childhood and/or adolescence. Discussion: The factor most strongly associated with BMI in this large population was disinhibition, suggesting that obesity treatment should target behaviors associated with disinhibition, especially in individuals showing a low level of dietary restraint. High restraint scores in formerly obese normal‐weight women suggest that dietary restraint may exert a beneficial influence on body weight control under conditions that deserve further investigation. 相似文献
10.
We studied the latent factor structure of the Beck Depression Inventory (BDI) under the light of Multidimensional Item Response Theory models. Under a Bayesian Markov chain Monte Carlo setting, we chose the most adequate model, estimated its parameters and verified its fit to the data. An evaluation of the inventory in terms of the assumed dimensions seems to agree with previous investigations in the factor structure of the BDI present in the literature. Cognitive and somatic‐affective latent traits were identified in the analysis making possible the interpretation of symptom evolution along these dimensions, in terms of probability of their appearance. 相似文献