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31.
Scenario-based investigations explore alternative future courses of action in a widening array of situations. Anticipating landscape patterns and the values behind them are recurring needs in such investigations. While it is accepted that how scenario assumptions are framed and who frames them matters, the sensitivity of resulting trajectories to contrasting scenario framing and modeling processes is rarely tested. Using comparable scenarios we contrast landscape change trajectories produced from two distinct approaches to modeling scenario assumptions: the first uses lay citizen groups and deterministic land allocation modeling, the second uses experts from biophysical and social sciences and agent-based modeling. Scenarios are defined and mapped for the year 2050 in western Oregon’s Willamette River Basin along a gradient of conservation oriented to development-oriented assumptions using first citizen-based and then expert-based approaches. The landscape variability and trajectories for the citizen-based Conservation 2050 and Development 2050 scenarios are then characterized and compared with those of the expert-based Conservation 2050 and Development 2050 scenarios. Results distinguish areas where trajectories always vary regardless of approach or scenario from those that never vary. Policy influence on trajectory is illustrated using agent-based model results where land conversion serves purposes of wealth production and ecosystem function. Results depict areas with strong coupling between policy and trajectory as those places experiencing the same pattern of change over time regardless of scenario. Results also indicate that the greater the variability of a given scenario’s trajectories, the more successful the scenario is at avoiding scarcity of wealth and ecosystem function.  相似文献   
32.
The objective of this study was to isolate bacteria on the skin of the proximal to distal equine limb to guide the practitioner in the selection of prophylactic antimicrobial protocols. This prospective study involved 20 client-owned horses that were admitted to the Veterinary Teaching Hospital for routine elective surgery. Each horse spent between 12 and 36 hours at our hospital before sampling. Samples were collected from the skin of the left mid-thorax and the dorsal aspect of nine joints on the left side of each horse: front and hind coffin and fetlock joints, carpi, elbows, shoulders, hocks, and stifles. Samples were cultured aerobically and speciated when possible. When evaluating bacterial composition by location, a 40% difference was considered clinically significant. When comparing proximal sites above the fetlock to distal sites, the odds of isolating gram-positive bacteria were 1.23 times (P = .0124) higher at proximal sites; the odds of isolating coliform bacteria were 1.32 times (P = .023) higher at distal sites; and the odds of isolating a common septic arthritis pathogen were 1.16 times (P = .018) higher at distal sites. Coagulase-positive Staphylococcus was not isolated in this study. All comparisons between sites and between the proximal and distal limb were <40%, and thus were not considered clinically significant. No coagulase-positive Staphylococcus was isolated from any of the 200 sites in this study, suggesting that iatrogenic infections by that organism may not be because of preexisting flora. These data suggest that antibiotic prophylaxis targeting preexisting normal flora should be similar regardless of the area of interest on the limb.  相似文献   
33.
Our objective was to determine effects of dietary high-oleate (Oleate; 76% 18:1) or high-linoleate (Linoleate; 78% 18:2) safflower seeds on fatty acids in muscle and adipose tissue of feedlot lambs. White-faced ewe lambs (n = 36) were fed a beet pulp, oat hay, and soybean meal basal diet (Control), blocked by BW, and allotted randomly to dietary treatments. Cracked safflower seeds were used in isocaloric and isonitrogenous replacement of beet pulp, oat hay, and soybean meal so that Oleate and Linoleate diets contained 5.0% additional fat. Fatty acids were determined in semitendinosus, longissimus dorsi (longissimus), and adipose tissue from the tail head (tailhead adipose tissue), adjacent to the 12th rib (s.c. adipose tissue), and kidney and pelvic fat (KPH adipose tissue) depots. Fatty acid data were analyzed within muscle and adipose tissue as a split-block design. Single degree of freedom orthogonal contrasts were used to compare treatment effects. Average daily gain, feed efficiency, and carcass characteristics did not differ (P = 0.15 to 0.96) across dietary treatments. Adipose tissue saturated fatty acids were greater (P = 0.04) for Controls but were not different (P = 0.36) in muscle. Trans-vaccenic acid (18:1(trans-11)) increased (P < 0.0001) with safflower supplementation and was greater (P < 0.0001) in Linoleate than in Oleate for both tissue types. Linoleate lamb had greater (P < 0.0001) PUFA than Oleate lamb in muscle and adipose tissue. Conjugated linoleic acids (CLA; cis-9, trans-11 and trans-10, cis-12) were greater (P < 0.0001) in muscle and adipose tissue of lambs fed safflower seeds. Lambs fed Linoleate had greater (P < 0.0001) CLA in adipose tissue and muscle than lambs fed Oleate. Saturated fatty acids were greater (P < 0.0001) in s.c. adipose tissue than in tailhead adipose tissue. Mono- and polyunsaturated fatty acids were greater (P < 0.0001) in tailhead adipose tissue than in s.c. adipose tissue. Weight percentages of 18:1(trans-11) ranked tailhead adipose tissue = KPH adipose tissue > s.c. adipose tissue and semitendinosus > longissimus, whereas CLA ranked tailhead adipose tissue > s.c. adipose tissue > KPH adipose tissue and semitendinosus > longissimus. Feeding mono- and polyunsaturated fatty acids increased tissue 18:1(trans-11) and CLA, which is a favorable change in regard to current human dietary guidelines.  相似文献   
34.

??Context

It is assumed that climate change will favour European beech (Fagus sylvatica L.) to Norway spruce (Picea abies [L.] Karst.) at its northern range margins due to climate change and induced disturbance events.

??Aims

An old-growth mixed forest of spruce and beech, situated near the northern beech margin, was studied to reveal effects of disturbances and response processes on natural forest dynamics, focussing on the understory.

??Methods

We carried out analyses on understory dynamics of beech and spruce in relation to overstory release. This was done based on a sequence of stand and tree vitality inventories after a series of abiotic and biotic disturbances.

??Results

It became apparent that beech (understory) has a larger adaptive capacity to disturbance impacts and overstory release (68 % standing volume loss) than spruce. Understory dynamics can play a key role for forest succession from spruce to beech-dominated forests. Disturbances display an acceleration effect on forest succession in the face of climate change.

??Conclusion

Beech is poised strategically to replace spruce as the dominant tree species at the study area. Due to an increasing productivity and a lower risk of stand failure, beech may raise into the focus of forestry in southern Sweden.  相似文献   
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