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81.
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. |
82.
The seasonal daily travel in a group of Sichuan snub-nosed monkey (Pygathrix roxellana) in Shennongjia Nature Reserve,China 总被引:3,自引:0,他引:3
Yiming L 《Primates; journal of primatology》2002,43(4):271-276
The seasonal daily travel of a group of snub-nosed monkey (Pygathrix roxellana) was investigated using the group’s straight-line distance method. The group was followed from dawn to dusk for 30 consecutive
days during each season to encompass all aspects of daily travel patterns. The results showed that in Summer and Autumn, the
mean daily travel distance (m) was significantly longer than in Winter and Spring. There was no significant difference in
the mean daily travel distance between Summer and Autumn or between Winter and Autumn. The mean travel distance (m/hr) during
daytime was significantly higher in Summer and Autumn than in Spring, and in Autumn than in Winter. The travel of the group
in all seasons had similar patterns. Traveling showed morning and afternoon peaks, with a rest period at the noon in a day.
Seasonal food availability, length of daytime, and mean travel distance (m/hr) during daytime might have contributed to the
different daily travel distances in different seasons. 相似文献
83.
Effects of artificial shade on attack by the mahogany shoot borer, Hypsipyla robusta (Moore) 总被引:2,自引:0,他引:2
R. M. Mahroof† C. Hauxwell† J. P. Edirisinghe A. D. Watt‡ A. C. Newton† 《Agricultural and Forest Entomology》2002,4(4):283-292
Abstract
- 1 Swietenia macrophylla King (Meliaceae: Swietenioideae) provides one of the premier timbers of the world. The mahogany shoot borer Hypsipyla robusta Moore (Lepidoptera: Pyralidae) is an economically important pest of S. macrophylla throughout Asia, Africa and the Pacific. No viable method of controlling this pest is known. Previous observations have suggested that the presence of overhead shade may reduce attack by H. robusta, but this has not been investigated experimentally. This research was therefore designed to assess the influence of light availability on shoot‐borer attack on S. macrophylla, by establishing seedlings under three different artificial shade regimes, then using these seedlings to test oviposition preference of adult moths, neonate larval survival and growth and development of shoot borer larvae.
- 2 Oviposition preference of shoot borer moths was tested on leaves from seedlings grown under artificial shade for 63 weeks. A significant difference in choice was recorded between treatments, with 27.4 ± 1.5 eggs laid under high shade and 87.1 ± 1.8 under low shade.
- 3 Neonate larval survival on early flushing leaflets of S. macrophylla did not differ significantly between shade treatments. Larval growth rate, estimated by measuring daily frass width, was significantly higher for those larvae fed on seedlings from the high and medium shade treatments (0.1 mm/day), than the low shade treatment (0.06 mm/day). In laboratory‐reared larvae, the total mass of frass produced was significantly higher in the high shade treatment (0.4 g) than under the low shade treatment (0.2 g).
- 4 Longer tunnel lengths were bored by larvae in plants grown under high shade (12.0 ± 2.4 cm) than under low shade (7.07 ± 1.9 cm). However, pupal mass under low shade was 48% higher than that under the high shade treatment, suggesting that plants grown under high shade were of lower nutritional quality for shoot borer larvae.
- 5 These results indicate that shading of mahogany seedlings may reduce the incidence of shoot borer attack, by influencing both oviposition and larval development. The establishment of mahogany under suitable shade regimes may therefore provide a basis for controlling shoot borer attack using silvicultural approaches.
84.
Natural<Superscript>15</Superscript> N Abundance of Plants and Soil N in a Temperate Coniferous Forest 总被引:3,自引:0,他引:3
Keisuke?Kobakkoba@depe.titech.ac.jp" title="kkoba@i.kyoto-u.ac.jp kkoba@depe.titech.ac.jp" itemprop="email" data-track="click" data-track-action="Email author" data-track-label="">Email author Muneto?Hirobe Lina?Koyama Ayato?Kohzu Naoko?Tokuchi Knute John?Nadelhoffer Eitaro?Wada Hiroshi?Takeda 《Ecosystems》2003,6(5):457-469
Measurement of nitrogen isotopic composition (15N) of plants and soil nitrogen might allow the characteristics of N transformation in an ecosystem to be detected. We tested the measurement of 15N for its ability to provide a picture of N dynamics at the ecosystem level by doing a simple comparison of 15N between soil N pools and plants, and by using an existing model. 15N of plants and soil N was measured together with foliar nitrate reductase activity (NRA) and the foliar NO3– pool at two sites with different nitrification rates in a temperature forest in Japan. 15N of plants was similar to that of soil NO3– in the high-nitrification site. Because of high foliar NRA and the large foliar NO3– pool at this site, we concluded that plant 15N indicated a great reliance of plants on soil NO3– there. However, many 15N of soil N overlapped each other at the other site, and 15N could not provide definitive evidence of the N source. The existing model was verified by measured 15N of soil inorganic N and it explained the variations of plant 15N between the two sites in the context of relative importance of nitrification, but more information about isotopic fractionations during plant N uptake is required for quantitative discussions about the plant N source. The model applied here can provide a basis to compare 15N signatures from different ecosystems and to understand N dynamics. 相似文献
85.
Biomass Partitioning and Gas Exchange in Dalbergia sissoo seedlings under water stress 总被引:3,自引:0,他引:3
Biomass, leaf water potential (l), net photosynthetic rate (P
N), transpiration rate (E), stomatal conductance (g
s), leaf to air temperature difference (T
diff), and instantaneous water use efficiency (WUE) were measured in the seedlings of Dalbergia sissoo Roxb. grown under irrigation of 20 (W1), 14 (W2), 10 (W3), and 8 (W4) mm. Treatments were maintained by re-irrigation when water content of the soil reached 7.4% in W1, 5.6% in W2, 4.3% in W3, and 3.2% in W4. Seedlings in a control (W5) were left without irrigation after maintaining the soil field capacity (10.7%). Seedlings of W1 had highest biomass that was one tenth in W5. Biomass allocation was highest in leaf in W2 and in root in W4 and W5 treatments. Difference between predawn leaf water potential (Pd) and midday (mid) increased with soil water stress and with vapour pressure deficit (VPD) in April and May slowing down the recovery in plant leaf water status after transpiration loss. P
N, E, and g
s declined and T
diff increased from W1 to W5. Their values were highly significant in April and May for the severely stressed seedlings of W4 and W5. P
N increased from 08:00 to 10:00 and E increased until 13:00 within the day for most of the seedlings whereas g
s decreased throughout the day from 08:00 to 17:00. P
N and E were highest in March but their values were low in January, February, April, and May. Large variations in physiological variables to air temperature, photosynthetically active radiation, and vapour pressure deficit (VPD) indicated greater sensitivity of the species to environmental factors. WUE increased from W1 to W2 but decreased drastically at high water stress particularly during hot summer showing a kind of adaptation in D. sissoo to water stress. However, low biomass and reduced physiological functions at <50% of soil field capacity suggest that this species does not produce significant biomass at severe soil water stress or drought of a prolonged period. 相似文献
86.
Totzke U Hübinger A Dittami J Bairlein F 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2000,170(8):627-631
To investigate the proximate influence of a changing food availability on the seasonal fattening of migratory birds, garden
warblers (Sylvia borin) following postnuptial moult were food restricted once a week. Body mass, food intake, plasma hormone and metabolite levels
were measured and compared to birds which always had ad libitum food access. The food-restricted birds increased their body
mass significantly earlier than the controls. The accelerated fattening was initially not accompanied by hyperphagia and may
be due to either an increased food utilisation efficiency or a reduced metabolic rate. An increase of basal glucagon and corticosterone
and a decrease of insulin levels prior to fattening were not significant, however, they resulted in a significant decrease
of the insulin:glucagon ratio. This ratio was also lower in food-restricted birds than in control birds and may account for
the difference in the fattening progress. We conclude that seasonal fattening may be stimulated by a catabolic impulse which
could be imposed in free-living birds by a decrease of food availability and/or by an increase of energy expenditure. A negative
energy balance is hypothesised to be a common proximate factor affecting migratory as well as winter fattening.
Accepted: 24 August 2000 相似文献
87.
Habitat choice in shoals of roach as a function of water temperature and feeding rate 总被引:2,自引:0,他引:2
Temperature and food availability are two important factors which affect fish growth and therefore are expected to influence habitat choice in fish. In this study, shoals of 16 juvenile roach, Rutilus rutilus , were given a choice between two chambers that differed in temperature by 1·5°C or 3°C whereas food availability was the same in both chambers (ratio 1 : 1) or higher in the colder one (ratio 4 : 1). The number of fish in each chamber was recorded for 10 min each during a pre-feeding, feeding and post-feeding period. Roach generally preferred the warmer over the colder chamber during the pre-feeding periods. Temperature had a significant effect on the distribution of fish during all three time periods whereas food availability was a significant factor only during the feeding period. The important role of temperature was emphasized further by the fact that a relatively small difference in the temperature gradient of 1·5°C had a stronger effect on fish distribution than a four times higher feeding rate during the feeding period. The implications for growth rates of such short-term decision-making of roach are discussed. 相似文献
88.
Nitrogen mineralization by bacterial-feeding nematodes: verification and measurement 总被引:15,自引:0,他引:15
Bacterial feeding nematodes excrete N assimilated in excess of that required for growth. Because metabolic and developmental rates differ among nematode species, we hypothesized that their contribution to N mineralization in soil would differ. Sand-column microcosms amended with an organic substrate, bacteria, and with or without bacterial-feeding nematodes, were leached at 3-d intervals. Cumulative N, as NH
4
+
or NO
3
-
, leached from columns containing nematodes was consistently greater than from columns without nematodes. Maximum N-mineralization rates for populations of rhabditid nematodes, which predominated in field soils early in the summer were at lower temperatures than those for cephalobid nematodes, which predominated later in the summer. For an organic substrate with C-to-N ratio of 11:1, rates of N mineralization among species of different body size were similar, ranging between 0.0012 and 0.0058 g-N nematode-1 d-1, mainly as NH
4
+
. Smaller nematodes mineralized more N per unit of body weight than larger nematodes. We hypothesized that at low C-to-N ratios of the organic substrate, bacterial growth is C-limited and N-immobilization will be minimal; at high C-to-N ratios bacterial growth will be N-limited and there may be rapid immobilization of newly-mineralized N. Consequently, net N mineralization in the presence of nematodes will be lower when the organic substrate has a high C-to-N ratio. In experiments with different nematode species, net mineralization and the nematode contribution to mineralization generally decreased with increasing C-to-N ratio, consistent with the hypothesis; however, there were exceptions. 相似文献
89.
We present a design to quantify fitness consequences of jasmonate-induced responses in plants that are competing for limited resources with a conspecific. Under both high and low nitrogen supply rates, uninduced (control) Nicotiana attenuata plants growing next to a plant induced with 250 μg methyl jasmonate (MJ) yielded more seed capsules than control plants competing with another control plant. We conclude that there is a opportunity benefit for control plants growing next to an induced plant. Initially, MJ-induced plants grew more slowly, but by senescence they had produced the same number of seed capsules as control plants that had competed with another control plant. Replacement series showed that the fitness of MJ-induced plants is not influenced by the competitive status of their neighbour plant. We argue that competitive designs are useful tools for evaluating the phenotypic costs of ecologically important traits. 相似文献
90.
Soybean meal was fermented withAspergillus usamii to improve zinc availability through the degradation of phytic acid. Rats fed a diet containing fermented soybean meal showed
greater femoral zinc than did animals fed a diet containing regular soybean meal. Zinc solubility in the small intestine was
higher in the rats fed fermented soybean meal than in the rats fed regular soybean meal. These results suggested that fermentation
withAspergillus usamii improved zinc availability in dietary soybean meal, which was induced by the increase of zinc solubility in the small intestine.
Adding the same amount of phytate that was contained in the regular soybean mealbased diet did not affect the amount of zinc
present in rats fed a fermented soybean meal-based diet with sodium phytate. Phytase activity was found in fermented soybean
meal, and this activity may degrade added phytate in fermented soybean meal-based diet. 相似文献