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Jerry T. Crews B. S. M.S. Willis G. Vogel B.S. M.S. 《Environmental geochemistry and health》1985,7(2):51-55
Evaluation of twelve minesoils collected from restored or abandoned surface mines in eastern Kentucky with six standard lime requirement procedures showed that one of the procedures accurately forecasted long term lime requirements. The minesoils were then evaluated for potassium choloride-extractable aluminum using the Yang exchangeable acidity procedure. When the extractable A13+ was multiplied by a factor of 2.24 it was found to also be an accurate measure for longterm limestone requirements. To bring the minesoil to pH 5.5 the results obtained using the modified Yuan procedure indicate that for each MEQ Al3+ extracted per 100 grams of minesoil 2.24 Mg of calcium carbonate (CaCO3) equivalent lime per hectare be applied. Application of lime based on this procedure and one of the standard lime procedures resulted in pH stability of the minesoils for forty months. 相似文献
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Carel?P.?van?SchaikEmail author Sagar?A.?Pandit Erin?R.?Vogel 《Behavioral ecology and sociobiology》2004,57(2):101-109
Perhaps the most common form of cooperation among primates is the formation of coalitions. Competition among males within a group concerns a constant quantity of the limiting resource (fertilizations). Contest competition over fertilizations is known to produce payoffs that are distributed according to the priority-of-access model, and hence show an exponential decline in payoff with rank. We develop a model for rank-changing, within-group coalitions among primate males. For these coalitions to occur, they must be both profitable (i.e. improve fitness) for all coalition members and feasible (i.e. be able to beat the targets). We assume that the value of the coalition is the sum of the payoffs of the partners in their original ranks. We distinguish three basic coalition configurations, depending on the dominance ranks of the coalition partners relative to their target. We predict five basic coalition types. First, all-up, rank-changing coalitions targeting individuals ranking above all coalition partners; these are expected to involve coalition partners ranking just below their target, concern top rank, and be small, just two or three animals. Second, bridging, rank-changing coalitions, where higher-rankers support lower-rankers to rise to a rank below themselves; these are expected to be most common where a high-ranking male in a despotic system can support a low-ranking relative. Third, bridging non-rank-changing coalitions; these are expected to be common whenever high-ranking males have low-ranking close relatives. Fourth, non-rank-changing coalitions by high-rankers against lower-ranking targets; these are expected to serve to counteract or prevent the first type. Fifth, non-rank-changing, leveling coalitions, in which all partners rank below their target and which flatten the payoff distribution; these are expected to be large and mainly involve lower-ranking males. Bridging, rank-changing coalitions are expected in situations where contest is strong, all-up rank-changing coalitions where contest is intermediate, and leveling coalitions where contest is weak. We review the empirical patterns found among primates. The strong predictions of the model are confirmed by observational data on male-male coalitions in primates.
相似文献
Carel P. van SchaikEmail: |
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JANINE BOLLIGER THOMAS C. EDWARDS JR. STEFAN EGGENBERG SASCHA ISMAIL IRMI SEIDL FELIX KIENAST 《Conservation biology》2011,25(3):567-576
Abstract: Abandonment of agricultural land has resulted in forest regeneration in species‐rich dry grasslands across European mountain regions and threatens conservation efforts in this vegetation type. To support national conservation strategies, we used a site‐selection algorithm (MARXAN) to find optimum sets of floristic regions (reporting units) that contain grasslands of high conservation priority. We sought optimum sets that would accommodate 136 important dry‐grassland species and that would minimize forest regeneration and costs of management needed to forestall predicted forest regeneration. We did not consider other conservation elements of dry grasslands, such as animal species richness, cultural heritage, and changes due to climate change. Optimal sets that included 95–100% of the dry grassland species encompassed an average of 56–59 floristic regions (standard deviation, SD 5). This is about 15% of approximately 400 floristic regions that contain dry‐grassland sites and translates to 4800–5300 ha of dry grassland out of a total of approximately 23,000 ha for the entire study area. Projected costs to manage the grasslands in these optimum sets ranged from CHF (Swiss francs) 5.2 to 6.0 million/year. This is only 15–20% of the current total estimated cost of approximately CHF30–45 million/year required if all dry grasslands were to be protected. The grasslands of the optimal sets may be viewed as core sites in a national conservation strategy. 相似文献
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Andrew H. Rose JR. Robert L. Stenburg Morton Corn Ronald R. Horsley Daniel R. Allen Paul W. Kolp 《Journal of the Air & Waste Management Association (1995)》2013,63(4):297-309
A survey of academic programs in air pollution control was made. Results from the 127 schools reporting are tabulated by state. Faculty involved in air pollution instruction are identified. Some conclusions and recommendations are presented. 相似文献
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A. C. Hill L. G. Transtrum M. R. Pack A. Holloman JR. 《Journal of the Air & Waste Management Association (1995)》2013,63(1):22-27
The principle of fabric filtration has only recently been accepted for fossil fuel fired boiler particulate emissions control. Information on design criteria is, therefore, limited. The paper provides data on the few installations where baghouses have been installed and successfully operated. The general conclusion is that a strong relationship exists between air to cloth ratio and bag life. 相似文献