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211.
This research examines whether the relationship between an individual's personality and their behavior within a team is contingent on the team's overall perception of its capability. Individuals were peer‐rated on the extent to which they displayed interpersonal and performance management teamwork behaviors over the course of an 8 week business simulation. The personality trait of agreeableness predicted interpersonal teamwork behavior, while the personality traits of conscientiousness and core self‐evaluation (CSE) predicted performance management behavior. Multilevel analysis showed that collective efficacy influenced the extent to which an individual engaged in both types of behavior, and was also a cross‐level moderator of the relationship between agreeableness and interpersonal behavior and the relationship between CSE and performance management behavior. At the team level, interpersonal behavior mediated between collective efficacy and team performance. The study's results show that in team settings the personality and individual behavior relationship may depend on group level confidence perceptions. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
212.
For two decades, the US Department of Agriculture, Forest Service, has been charged with implementing a nationwide field-based forest health monitoring effort. Given its extensive nature, the monitoring program has been gradually implemented across forest health indicators and inventoried states. Currently, the Forest Service??s Forest Inventory and Analysis program has initiated forest health inventories in all states, and most forest health indicators are being documented in terms of sampling protocols, data management structures, and estimation procedures. Field data from most sample years and indicators are available on-line with numerous analytical examples published both internally and externally. This investment in national forest health monitoring has begun to yield dividends by allowing evaluation of state/regional forest health issues (e.g., pollution and invasive pests) and contributing substantially to national/international reporting efforts (e.g., National Report on Sustainability and US EPA Annual Greenhouse Gas Estimates). With the emerging threat of climate change, full national implementation and remeasurement of a forest health inventory should allow for more robust assessment of forest communities that are undergoing unprecedented changes, aiding future land management and policy decisions.  相似文献   
213.
We study the optimal hardwood tree planting decision on reclaimed surface coal mines in the Appalachian region using a mine operator-focused, expected cost model that recognizes costs of preparing the site for tree planting, unit costs of planting seedlings, and opportunity costs of reforestation treatments and the performance bond. We also consider the possibility of failed initial attempts by incorporating the probability of reforestation success, based on empirical seedling ,survival rates and regulated tree survival standards, as well as fixed and unit costs of returning for additional planting. Optimal planting levels from 319 to 780 trees per acre and expected costs from $1049 to $2338 were found using simulations over a range of unit planting costs, fixed costs of replanting, tree survival standards, and interest rates. Further simulations compared optimal planting across un-weathered gray sandstone and weathered brown sandstone substrate materials, finding gray sandstone to be associated with lower expected costs. We conclude that optimal planting density and expected reforestation cost are sensitive to economic parameters, regulations, and planting substrate materials; and those policies influencing these factors may have substantial impact on reforestation outcomes and the choice of post-mining land use by mine operators. Our study provides a framework for understanding forest reclamation decisions that incorporates incentives faced by the mine operators who develop and implement the plans for mine reclamation, including forestry.  相似文献   
214.
Excessive production of methane has been observed at some remediation sites following the addition of organic hydrogen donors such as (emulsified) oils/lecithin, sugars, and conventional carbon + zero‐valent iron (ZVI) amendments. This is due to the fact that methanogens are commonly the most ubiquitous indigenous microbes in anoxic aquifer settings, and, under enriched environmental conditions, methanogens replicate every one to two hours (whereas Dehalococcoides spp., e.g., double in 24–48 hr). Hence, methanogens often bloom and dominate the microbial ecosystem following the addition of remedial amendments, thereby liberating large amounts of methane gas. There are at least three important consequences of this response:
  1. By utilizing hydrogen, the methanogens compete with dechlorinating microbes, thus making inefficient use of the remedial amendment (just 20 ppm methane in groundwater represents an approximate 30 percent “waste” of added fermentable substrate (i.e., hydrogen donor)—this is a common and tangible detriment);
  2. Methanogens can methylate heavy metals and their rapid growth consumes alkalinity, while generating acidity, thereby facilitating multiple potential mechanisms for creating secondary contaminant issues (i.e., arsenic plumes); and
  3. Elevated methane concentrations can exceed current and pending regulations of <10 to <28 ppm methane in groundwater and/or 0.5 percent by volume methane in soil gas (e.g., 10 percent of the lower explosive limit) and/or indoor air (methane is flammable between 5 percent and 15 percent by volume) and this will induce migration of contaminant vapors potentially causing indoor air issues.
Considering the recent guidelines for indoor air published by the US Environmental Protection Agency, it is increasingly important to prevent excessive methanogenesis associated with remedial actions. From a regulatory perspective, public safety issues are paramount; from a property re‐use or real estate (brownfield) developers’ perspective, project delays are costly and can jeopardize an entire program. The use of antimethanogenic compounds as inhibitors of protein biosynthesis and the activity of enzyme systems unique to Archaea (i.e., methanogens) during in situ remedial action can improve contaminant removal while offering safer, more efficacious treatment, simply by impeding the methanogenic bacteria's ability to proliferate and out compete desired bacterial communities (e.g., Dehalococcoides spp.). ©2016 Wiley Periodicals, Inc.  相似文献   
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