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31.
32.

Context

Conservation planning is increasingly using “coarse filters” based on the idea of conserving “nature’s stage”. One such approach is based on ecosystems and the concept of ecological integrity, although myriad ways exist to measure ecological integrity.

Objectives

To describe our ecosystem-based index of ecological integrity (IEI) and its derivative index of ecological impact (ecoImpact), and illustrate their applications for conservation assessment and planning in the northeastern United States.

Methods

We characterized the biophysical setting of the landscape at the 30 m cell resolution using a parsimonious suite of settings variables. Based on these settings variables and mapped ecosystems, we computed a suite of anthropogenic stressor metrics reflecting intactness (i.e., freedom from anthropogenic stressors) and resiliency metrics (i.e., connectivity to similar neighboring ecological settings), quantile-rescaled them by ecosystem and geographic extent, and combined them in a weighted linear model to create IEI. We used the change in IEI over time under a land use scenario to compute ecoImpact.

Results

We illustrated the calculation of IEI and ecoImpact to compare the ecological integrity consequences of a 70-year projection of urban growth to an alternative scenario involving securing a network of conservation core areas (reserves) from future development.

Conclusions

IEI and ecoImpact offer an effective way to assess ecological integrity across the landscape and examine the potential ecological consequences of alternative land use and land cover scenarios to inform conservation decision making.
  相似文献   
33.
Two horses referred to the Unitat Equina, Fundació Hospital Clínic Veterinari, Universitat Autònoma de Barcelona, for unrelated clinical problems, and with no previous history of cardiac disease exhibited an intermittent ventricular pre-excitation electrocardiographic pattern during hospitalization. Both animals showed decreased plasma total and ionized magnesium concentrations, but no other relevant electrolyte disturbances were detected. Altered interventricular septal motion associated with ventricular pre-excitation beats (VPBs) was detected on M-mode echocardiography in both horses. The likely localization of an accessory pathway (AP) was identified in case 2 using pulsed-wave tissue Doppler imaging in the left anterior paraseptal location. Decreased frequency of the VPB was observed with long-term magnesium supplementation and restoration of plasma magnesium concentrations. The presence of ventricular pre-excitation electrocardiographic pattern was attributed to higher sensitivity of the AP to hypomagnesemia in both cases.  相似文献   
34.
35.
Ohne ZusammenfassungMitteilung aus der Heffischen forstlichen Versuchsanstalt in Gießen.  相似文献   
36.

Background  

The continued depletion of tropical rainforests and fragmentation of natural habitats has led to significant ecological changes which place most top carnivores under heavy pressure. Various methods have been used to determine the status of top carnivore populations in rainforest habitats, most of which are costly in terms of equipment and time. In this study we utilized, for the first time, a rigorous track classification method to estimate population size and density of clouded leopards (Neofelis nebulosa) in Tabin Wildlife Reserve in north-eastern Borneo (Sabah).  相似文献   
37.
The carbonization process causes different physical and chemical transformations to wood, affecting the final properties of the charcoal produced. In Brazil, the cutting and use of Ocotea porosa (Nees & Mart. Ex Nees) L. Barroso is legally prohibited. But the difficulty of identifying the species used to produce charcoal hinders enforcement efforts to protect this and other endangered tree species. The aim of this work was to characterize the anatomy of charcoal made from O. porosa at different temperatures to provide information to facilitate differentiation of the species by the authorities in charge of suppressing illegal commerce. Samples were carbonized by direct heating and final temperatures of 350, 450 and 650 °C, besides a group under a ramp heating regime also with a final temperature of 450 °C. The qualitative characteristics of the O. porosa wood were preserved at the carbonization temperatures studied permitting the use of its anatomical structures for identification of carbonized wood to support control of the illegal trade in charcoal of this species.  相似文献   
38.
The effect of bacteria represented by indigenous soil microflora or a mixture of soil bacteria Pseudomonas aeruginosa and Rhodococcus erythropolis on fungal growth, extracellular enzyme production and polycyclic aromatic hydrocarbons (PAHs) biodegradation efficiency in soil of white-rot fungi Trametes versicolor and Irpex lacteus was investigated. Both fungi were able to colonize soil. The growth yields measured by ergosterol were about two-fold in I. lacteus after 10 weeks. Laccase was produced in T. versicolor cultures in the presence or absence of bacteria but live bacteria reduced the laccase levels in soil about 5 times. Manganese-dependent peroxidase (MnP) was not detected in T. versicolor cultures. The amounts of MnP and laccase in I. lacteus cultures were not affected by the presence of bacteria. T. versicolor was more efficient in PAH removal for all PAHs tested although its capacity to colonize soil was lower. The removal rates of PAHs by T. versicolor in sterile soil were 1.5-fold, 5.8-fold and 1.8-fold for 2-3-ring, 4-ring and 5-6-ring PAHs, compared to I. lacteus, respectively. I. lacteus showed a low efficiency of removal of pyrene, benzo[a]anthracene and benzo[k]fluoranthene, compared to T. versicolor, whereas chrysene and benzo[b]fluoranthene were degraded by neither fungus. The main effect of the presence of the indigenous microflora or R. erythropolis and P. aeruginosa was a significant decrease of degradation of total PAHs by both T. versicolor and I. lacteus. Weak fungal/bacterial synergistic effects were observed in the case of removal of acenapthylene, benzo[a]pyrene, dibenzo[a,h]anthracene and benzo[g,h,i]perylene by I. lacteus and acenapthylene by T. versicolor. However, the bacterial effects were different in the two fungi. PAH abiotic losses represented 15 and 21% of the total PAHs after 5 and 10 weeks, respectively; naphthalene and acenaphthene were removed from the soil due to volatilization.  相似文献   
39.
There is evidence in the literature that the ratio of mass of sorbent (M) to volume of solution (V) affects the results of batch tests with soils and sediments. This restricts the use of such data to conditions with the same M/V ratio they were derived with, unless its influence is corrected. To find a correction, we conducted batch tests with soil and zinc solution using four M/V ratios. For each ratio, the experiments produced a different relationship between the mass of zinc sorbed per unit mass of soil (a s) and the zinc concentration in the solution after shaking and removal of the solid phase (C det), which is usually taken as the equilibrium concentration (C eq). A theoretical analysis revealed that the M/V effect can be accounted for by dividing C det by the M/V ratio, if it is caused by the presence of a “third phase”. The relationship between a s and C det×V/M is the same for all ratios then.  相似文献   
40.
Fatiguing exercise substantially decreases muscle glycogen concentration in horses, impairing athletic performance in subsequent exercise bouts. Our objective was to determine the effect of ingestion of starch-rich meals after exercise on whole body glucose kinetics and muscle glycogen replenishment. In a randomized, cross-over study seven horses with exercise-induced muscle glycogen depletion were either not fed for 8 h, fed half of the daily energy requirements ( approximately 15 Mcal DE) as hay, or fed an isocaloric amount of corn 15 min and 4 h after exercise. Starch-rich meals fed after exercise, when compared to feed withholding, resulted in mild to moderate hyperglycemia (5.7+/-0.3 vs. 4.7+/-0.3 mM, P<0.01) and hyperinsulinemia (79.9+/-9.3 vs. 39.0+/-1.9 pM, P<0.001), 3-fold greater whole body glucose kinetics (15.5+/-1.4 vs. 5.3+/-0.4 micromol kg(-1)min(-1), P<0.05), but these only minimally enhanced muscle glycogen replenishment (171+/-19 vs. 170+/-56 and 260+/-45 vs. 294+/-29 mmol/kg dry weight immediately and 24 h after exercise, P>0.05). It is concluded that after substantial exercise-induced muscle glycogen depletion, feeding status only minimally affects net muscle glycogen concentrations after exercise, despite marked differences in soluble carbohydrate ingestion and availability of glucose to skeletal muscle.  相似文献   
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