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Environmental Science and Pollution Research - The poor adsorption capacity of sandy soils is one of the primary reasons of a high level of phosphorus (P) leaching. Silicon (Si)-rich soil...  相似文献   
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Inbreeding depression is an important long-term threat to reintroduced populations. However, the strength of inbreeding depression is difficult to estimate in wild populations because pedigree data are inevitably incomplete and because good data are needed on survival and reproduction. Predicting future population consequences is especially difficult because this also requires projecting future inbreeding levels and their impacts on long-term population dynamics, which are subject to many uncertainties. We illustrate how such projections can be derived through Bayesian state-space modeling methods based on a 26-year data set for North Island Robins (Petroica longipes) reintroduced to Tiritiri Matangi Island in 1992. We used pedigree data to model increases in the average inbreeding level (F ) over time based on kinship of possible breeding pairs and to estimate empirically Ne/N (effective/census population size). We used multiple imputation to model the unknown components of inbreeding coefficients, which allowed us to estimate effects of inbreeding on survival for all 1458 birds in the data set while modeling density dependence and environmental stochasticity. This modeling indicated that inbreeding reduced juvenile survival (1.83 lethal equivalents [SE 0.81]) and may have reduced subsequent adult survival (0.44 lethal equivalents [0.81]) but had no apparent effect on numbers of fledglings produced. Average inbreeding level increased to 0.10 (SE 0.001) as the population grew from 33 (0.3) to 160 (6) individuals over the 25 years, giving a ratio of 0.56 (0.01). Based on a model that also incorporated habitat regeneration, the population was projected to reach a maximum of 331–1144 birds (median 726) in 2130, then to begin a slow decline. Without inbreeding, the population would be expected stabilize at 887–1465 birds (median 1131). Such analysis, therefore, makes it possible to empirically derive the information needed for rational decisions about inbreeding management while accounting for multiple sources of uncertainty.  相似文献   
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Environmental Science and Pollution Research - Food waste management (FWM) is considered to be an extremely important social issue besides an environmental one. Worldwide, it is estimated that 1.3...  相似文献   
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We designed 3 image‐based field guides to tropical forest plant species in Ghana, Grenada, and Cameroon and tested them with 1095 local residents and 20 botanists in the United Kingdom. We compared users’ identification accuracy with different image formats, including drawings, specimen photos, living plant photos, and paintings. We compared users’ accuracy with the guides to their accuracy with only their prior knowledge of the flora. We asked respondents to score each format for usability, beauty, and how much they would pay for it. Prior knowledge of plant names was generally low (<22%). With a few exceptions, identification accuracy did not differ significantly among image formats. In Cameroon, users identifying sterile Cola species achieved 46–56% accuracy across formats; identification was most accurate with living plant photos. Botanists in the United Kingdom accurately identified 82–93% of the same Cameroonian species; identification was most accurate with specimens. In Grenada, users accurately identified 74–82% of plants; drawings yielded significantly less accurate identifications than paintings and photos of living plants. In Ghana, users accurately identified 85% of plants. Digital color photos of living plants ranked high for beauty, usability, and what users would pay. Black and white drawings ranked low. Our results show the potential and limitations of the use of field guides and nonspecialists to identify plants, for example, in conservation applications. We recommend authors of plant field guides use the cheapest or easiest illustration format because image type had limited bearing on accuracy; match the type of illustration to the most likely use of the guide for slight improvements in accuracy; avoid black and white formats unless the audience is experienced at interpreting illustrations or keeping costs low is imperative; discourage false‐positive identifications, which were common; and encourage users to ask an expert or use a herbarium for groups that are difficult to identify. Pruebas Empíricas de Guías de Campo de Plantas Hawthorne, Cable & Marshall  相似文献   
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Activated ZnO powder has been prepared by procedures involving first its dissolution in nitric acid, then simultaneous treatment by adding NH4OH and CO2 bubbling leading to precipitation as Zn(OH)CO3 (ZH) and further thermal decomposition of ZH at 400 °C. The gas evolution leads to formation of pores and increase in the specific surface area. Chemically activated M/ZnO powders doped with Mn, Co, Ni, Cu, and Ag have been obtained by the impregnation method. The samples have been characterized by ultraviolet-visible (UV-Vis) spectroscopy, diffuse reflectance (DR) UV-Vis, X-ray diffraction (XRD), single point Brunauer–Emmet–Teller (BET), scanning electron microscope (SEM), and X-ray photoelectron spectroscopy (XPS) methods. The experiments have shown that metal-doped activated ZnO powders possess higher photocatalytic activities in oxidative discoloration of model contaminant textile coloring dye Reactive Black 5 in slurry reactor compared to that of the pure ZnO. The XRD and XPS data have shown the presence of defects, nonstoichiometricity implying the formation of solid solutions. Copper-doped (1.5 wt%) activated ZnO (Cu2+ replaces Zn2+) is outstanding in its photocatalytic performance in discoloration of the dye due to the higher specific surface area and improved charge carrier separation.  相似文献   
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