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11.
Opportunities and Challenges of Carbon Footprint,Climate or CO2 Labelling for Horticultural Products
The number of fruits on the German and European markets with a carbon label is on the increase. This contribution reviews the existing carbon labels by evaluating, categorising and giving background information to provide guidance for labelling home-grown horticultural produce. The existing labels worldwide were classified in 10 categories: (1) CO2 value; (2) Colour code (with or without CO2 value); (3) CO2 reduction (Carbon Trust, Tesco’s, UK) or conversion labels; (4) Climatop for Migros, Switzerland (temporal label for the best product within a product category, e.g., banana, rice, salt); (5) Airfreight labels, e.g., Marks & Spencer’s UK (without further information); (6) ‘Climate, carbon offset or CO2-neutral’, e.g., NewTree, (only when using gold standard CO2 emission certificates); (7) unaccounted CO2 compensation measures (such as planting young trees: ‘CO2 pineapple’ in Costa Rica); (8) Sustainability labels (ProPlanet, REWE), (9) sustainability reports (printed or online) and (10) QR-Code on the shelf or product to access web-based information. The ‘Pros and Cons’ of the climate labels are compared with respect to the seasonal fruit and vegetables often sold on the markets as lose items and the stakeholder interest. Labelling approaches 4, 8, 9 and 10 appeared suitable for seasonal fruits and vegetables based on criteria such as transparency, clarity, objectivity and integration in the sustainability context. Overall, it is difficult to use labels with a CO2 value for horticultural products, because (a) the consumer may find it difficult to judge and memorise numeric values, particularly if expressed on different units (e.g. packet size, 1 l, 100 g) and (b) because of the big variation between the farm production systems and the variability between the year to year weather and (c) the consumer may find shopping with a seasonal crop calendar and country of origin label a better choice. 相似文献
12.
The effects of vaccination of Merino ewes with an attenuated Australian bluetongue virus serotype 23 at different stages of gestation 总被引:1,自引:0,他引:1
SUMMARY A cell culture attenuated Australian bluetongue virus serotype 23 (BLU23) prototype vaccine was assessed for its effects on pregnant Merino sheep. Seventy-six ewes were vaccinated at 5 different stages of gestation, and the failure to lamb at term was as follows: 35 to 43 days of gestation, 20/36 (56%); 57 to 64 days of gestation, 3/10 (30%); 81 to 88 days of gestation, 3/10 (30%); 109 to 116 days of gestation, 0/10 (0%); 130 to 137 days of gestation, 0/10 (0%). Of 30 ewes vaccinated with a cell culture supernatant fluid control between 35 and 43 days of gestation, 6.7% (2/30) failed to lamb at term. Two ewes vaccinated with BLU23 vaccine between 35 and 43 days of gestation had lambs with hydranencephaly. All other lambs born were clinically normal. Three ewes vaccinated with BLU23 aborted. Two of these were vaccinated between 35 and 43 days of gestation, the 3rd between 81 and 88 days of gestation. Five lambs were born with BLU group antibody. Four of these were from ewes vaccinated between 35 and 43 days of gestation, and 2 of these had hydranencephaly. The fifth was from a ewe vaccinated between 57 and 64 days of gestation. The vaccine did not produce disease in adult sheep, but was a potent cause of early foetal death and to a much lesser extent foetal malformation. 相似文献
13.
Ground-layer vegetation was sampled along selected trail corridors to determine whether corridors provide habitat for certain species and act as conduits for species movement. Patterns of plant species composition were analyzed in relation to distance from trail edge, level of trail use, and distance from trailheads, junctions, and campgrounds. Species composition was significantly affected by distance from trail edge and level of trail use, as species were favored or inhibited by the corridor, depending upon their growth habits. Species composition was also affected by distance from trailheads. These findings, along with the presence of exotic species, indicate that trail corridors in Rocky Mountain National Park function as habitat and conduits for movement of plant species. 相似文献
14.
We used ionic tracers to estimate the volume of old (soil and ground) water interacting with snowmelt in eleven Adirondack, NY watersheds. The contribution of old water varied from 66 to 90%, with no general relationship between old water % and soil depth to till. This approach also discriminated between watershed retention and release of particular ions to lake outlet water during snowmelt. Most watersheds released NO3 ? during snowmelt, in addition to the snowpack NO3 ?. Nitrification of snowpack NH4 + explained part of the additional NO3 ? in lake out outlet water, but some NO3 ? was likely mineralized nitrogen from soil organic matter. All watersheds retained NH4 + as well. Nitrogen release was greatest in the acidic watersheds in the southwestern Adirondacks, a region thought to be impacted by anthropogenic deposition. During snowmelt, Ca2+ and Mg2+ ions (presumably from soil exchange sites) were also released from most watersheds. In watersheds with acidic (minimum pH<4.6) lake outlet water, Al was also released during snowmelt. Thus, lake outlet water acidification during snowmelt was both buffered by cation release, and intensified by NO3 ? release. If the soil exchangeable cation pools were not replenished prior to snowmelt, or NO3 ? mobilization were increased, acidification during snowmelt would intensify. 相似文献
15.
J Schaefer K J Kramer J R Garbow G S Jacob E O Stejskal T L Hopkins R D Speirs 《Science (New York, N.Y.)》1987,235(4793):1200-1204
Cross-polarization magic-angle-spinning nuclear magnetic resonance spectroscopy has been used to determine insect cuticle composition and cross-link structure during sclerotization or tanning. Unsclerotized cuticle from newly ecdysed pupae of the tobacco hornworm, Manduca sexta L., had a high protein content with lesser amounts of lipid and chitin. Concentrations of chitin, protein, and catechol increased substantially as dehydration and sclerotization progressed. Analysis of intact cuticle specifically labeled with carbon-13 and nitrogen-15 revealed direct covalent linkages between ring nitrogens of protein histidyl residues and ring carbons derived from the catecholamine dopamine. This carbon-nitrogen adduct was present in chitin isolated from cuticle by alkaline extraction and is probably bound covalently to chitin. These data support the hypothesis that the stiffening of insect cuticle during sclerotization results primarily from the deposition of protein and chitin polymers and their crosslinking by quinonoid derivatives of catecholamines. 相似文献
16.
Subjects with type III hyperlipoproteinemia develop premature atherosclerosis and have hyperlipidemia due to an increase in cholesterol-rich very low density lipoproteins (VLDL) of abnormal electrophoretic mobility. Apolipoprotein E is a major protein constituent of VLDL and appears to be important for the hepatic uptake of triglyceride-rich lipoproteins. A new kindred of patients with type III hyperlipoproteinemia is described in which no plasma apolipoprotein E could be detected, consistent with the concept that type III hyperlipoproteinemia may be due to an absence or striking deficiency of apolipoprotein E. 相似文献
17.
Schaefer VJ 《Science (New York, N.Y.)》1946,104(2707):457-459
18.
A series of organic salts, in which the cation has been designed to have a large molecular hyperpolarizability, has been prepared. Variation of the counterion (anion) in many cases leads to materials with large powder second harmonic generation efficiencies, the highest of which is roughly 1000 times that of a urea reference. 相似文献
19.
The dynamics of a fluid surface filled with high-amplitude ripples were studied with a technique (diffusing light photography) that resolves the height at all locations instantaneously. Even when nonlinearities are strong enough to generate a (Kolmogorov) cascade from long wavelength (where energy is input) to shorter wavelength, the resulting turbulent state contains large coherent spatial structures. The appearance of these structures in a thermal equilibrium state (with the same average energy) would be highly improbable. 相似文献
20.
The extent to which synaptic activity can signal a sensory stimulus limits the information available to a neuron. We determined the contribution of individual synapses to sensory representation by recording excitatory postsynaptic currents (EPSCs) in cerebellar granule cells during a time-varying, quantifiable vestibular stimulus. Vestibular-sensitive synapses faithfully reported direction and velocity, rather than position or acceleration of whole-body motion, via bidirectional modulation of EPSC frequency. The lack of short-term synaptic dynamics ensured a highly linear relationship between velocity and charge transfer, and as few as 100 synapses provided resolution approaching psychophysical limits. This indicates that highly accurate stimulus representation can be achieved by small networks and even within single neurons. 相似文献