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521.
Russell C. Van Horn Jason C. Buchan Jeanne Altmann Susan C. Alberts 《Behavioral ecology and sociobiology》2007,61(12):1823-1837
Group living provides benefits to individuals while imposing costs on them. In species that live in permanent social groups,
group division provides the only opportunity for nondispersing individuals to change their group membership and improve their
benefit to cost ratio. We examined group choice by 81 adult female savannah baboons (Papio cynocephalus) during four fission events. We measured how each female’s group choice was affected by several factors: the presence of
her maternal kin, paternal kin, age peers, and close social partners, her average kinship to groupmates, and her potential
for improved dominance rank. Maternal kin, paternal kin, and close social partners influenced group choice by some females,
but the relative importance of these factors varied across fissions. Age peers other than paternal kin had no effect on group
choice, and average kinship to all groupmates had the same effect on group choice as did maternal kin alone. Most females
were subordinate to fewer females after fissions than before, but status improvement did not drive female group choice; females
often preferred to remain with social superiors who were their close maternal kin, rather than improving their own social
ranks. We suggest that during permanent group fissions, female baboons prefer to remain with close maternal kin if those are
abundant enough to influence their fitness; if they have too few close maternal kin then females prefer to remain with close
paternal kin, and social bonds with nonkin might also become influential.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
522.
Nitrous oxide nitrification and denitrification 15N enrichment factors from Amazon forest soils. 总被引:1,自引:0,他引:1
Tibisay Pérez Diana Garcia-Montiel Susan Trumbore Stanley Tyler Plínio de Camargo Marcelo Moreira Marisa Piccolo Carlos Cerri 《Ecological applications》2006,16(6):2153-2167
The isotopic signatures of 15N and 18O in N2O emitted from tropical soils vary both spatially and temporally, leading to large uncertainty in the overall tropical source signature and thereby limiting the utility of isotopes in constraining the global N2O budget. Determining the reasons for spatial and temporal variations in isotope signatures requires that we know the isotope enrichment factors for nitrification and denitrification, the two processes that produce N2O in soils. We have devised a method for measuring these enrichment factors using soil incubation experiments and report results from this method for three rain forest soils collected in the Brazilian Amazon: soil with differing sand and clay content from the Tapajos National Forest (TNF) near Santarém, Pará, and Nova Vida Farm, Rond?nia. The 15N enrichment factors for nitrification and denitrification differ with soil texture and site: -111 per thousand +/- 12 per thousand and -31 per thousand +/- 11 per thousand for a clay-rich Oxisol (TNF), -102 per thousand +/- 5 per thousand and -45 per thousand +/- 5 per thousand for a sandier Ultisol (TNF), and -10.4 per thousand +/- 3.5 per thousand (enrichment factor for denitrification) for another Ultisol (Nova Vida) soil, respectively. We also show that the isotopomer site preference (delta15Nalpha - delta15Nbeta, where alpha indicates the central nitrogen atom and beta the terminal nitrogen atom in N2O) may allow differentiation between processes of production and consumption of N2O and can potentially be used to determine the contributions of nitrification and denitrification. The site preferences for nitrification and denitrification from the TNF-Ultisol incubated soils are: 4.2 per thousand +/- 8.4 per thousand and 31.6 per thousand +/- 8.1 per thousand, respectively. Thus, nitrifying and denitrifying bacteria populations under the conditions of our study exhibit significantly different 15N site preference fingerprints. Our data set strongly suggests that N2O isotopomers can be used in concert with traditional N2O stable isotope measurements as constraints to differentiate microbial N2O processes in soil and will contribute to interpretations of the isotopic site preference N2O values found in the free troposphere. 相似文献
523.
Hawes AK Solomon S Portmann RW Daniel JS Langford AO Miller HL Eubank CS Goldan P Wiedinmyer C Atlas E Hansel A Wisthaler A 《Journal of environmental monitoring : JEM》2003,5(6):977-983
Measuring hydrocarbons from aircraft represents one way to infer biogenic emissions at the surface. The focus of this paper is to show that complementary remote sensing information can be provided by optical measurements of a vegetation index, which is readily measured with high temporal coverage using reflectance data. We examine the similarities between the vegetation index and in situ measurements of the chemicals isoprene, methacrolein, and alpha-pinene to estimate whether the temporal behavior of the in situ measurements of these chemicals could be better understood by the addition of the vegetation index. Data were compared for flights conducted around Houston in August and September 2000. The three independent sets of chemical measurements examined correspond reasonably well with the vegetation index curves for the majority of flight days. While low values of the vegetation index always correspond to low values of the in situ chemical measurements, high values of the index correspond to both high and low values of the chemical measurements. In this sense it represents an upper limit when compared with in situ data (assuming the calibration constant is adequately chosen). This result suggests that while the vegetation index cannot represent a purely predictive quantity for the in situ measurements, it represents a complementary measurement that can be useful in understanding comparisons of various in situ observations, particularly when these observations occur with relatively low temporal frequency. In situ isoprene measurements and the vegetation index were also compared to an isoprene emission inventory to provide additional insight on broad issues relating to the use of vegetation indices in emission database development. 相似文献
524.
Heinz Gary H. Erdman Thomas C. Haseltine Susan D. Stafford Charles 《Environmental monitoring and assessment》1985,5(3):223-236
Residues of organochlorine pesticides, polychlorinated biphenyls (PCBs), polybrominated biphenyls (PBBs), polychlorinated styrenes (PCSs), and mercury were measured in the eggs of 10 species of colonial waterbirds nesting in areas around Green Bay or Lake Michigan from 1975 to 1980. Residues also were measured in the carcasses and brains of black-crowned night-herons (Nycticorax nycticorax). The highest residues were of PCBs, DDE, mercury, and dieldrin; for some species, levels of these chemicals possibly were high enough to have caused reproductive effects. Other organochlorine pesticides were found at low levels. Only trace amounts of PCSs and PBBs were found. Eggs of herring gulls (Larus argentatus) collected in 1977 from an island in Lake Michigan contained an average of 100 ppm PCBs and 33 ppm DDE; this was the most-contaminated species. Cattle egrets (Bubulcus ibis), the only bird that is not a fish eater, contained only small quantities of DDE and mercury. 相似文献
525.
Russell J. Hall Susan D. Haseltine Paul H. Geissler 《Environmental monitoring and assessment》1989,13(1):11-19
Comparison of organochlorine residues in wildlife must often be made to regulatory standards or to values of known biological significance; this is difficult when dissimilar tissues are analyzed and results are expressed on different bases. To relate levels in the different tissues used for regulatory and monitoring purposes and for biological assessments, we exposed American black ducks to mixtures of three organochlorines. Differences in residue burdens among tissues were not statistically significant when levels were expressed on a lipid weight basis. Levels of heptachlor and Aroclor 1254 in one tissue can be accurately predicted from those in another; such predictions for endrin are less reliable. Lipid weight based residue concentrations in wings may be used to predict whether levels in fat exceed residue standards set for human health or approach those associated with effects on populations of species sampled. 相似文献
526.
Christine Susan Fagnant Liliana Margarita Sánchez-Gonzalez Nicolette A. Zhou Jill Christin Falman Michael Eisenstein Dylan Guelig Byron Ockerman Yifei Guan Alexandra Lynn Kossik Yarrow S. Linden Nicola Koren Beck Robyn Wilmouth Evans Komen Benlick Mwangi James Nyangao Jeffry H. Shirai Igor Novosselov Peter Borus David S. Boyle John Scott Meschke 《Food and environmental virology》2018,10(1):72-82
Environmental surveillance of poliovirus (PV) plays an important role in the global program for eradication of wild PV. The bag-mediated filtration system (BMFS) was first developed in 2014 and enhances PV surveillance when compared to the two-phase grab method currently recommended by the World Health Organization (WHO). In this study, the BMFS design was improved and tested for its usability in wastewater and wastewater-impacted surface waters in Nairobi, Kenya. Modifications made to the BMFS included the size, color, and shape of the collection bags, the filter housing used, and the device used to elute the samples from the filters. The modified BMFS concentrated 3–10 L down to 10 mL, which resulted in an effective volume assayed (900–3000 mL) that was 6–20 times greater than the effective volume assayed for samples processed by the WHO algorithm (150 mL). The system developed allows for sampling and in-field virus concentration, followed by transportation of the filter for further analysis with simpler logistics than the current methods. This may ultimately reduce the likelihood of false-negative samples by increasing the effective volume assayed compared to samples processed by the WHO algorithm, making the BMFS a valuable sampling system for wastewater and wastewater-impacted surface waters. 相似文献
527.
Smoldering Combustion (STAR) for the Treatment of Contaminated Soils: Examining Limitations and Defining Success
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Gavin P. Grant David Major Grant C. Scholes John Horst Susan Hill Mark R. Klemmer James Neil Couch 《补救:环境净化治理成本、技术与工艺杂志》2016,26(3):27-51
Smoldering combustion, commercially available as the Self‐sustaining Treatment for Active Remediation (STAR) technology, is an innovative technique that has shown promise for the remediation of contaminant source zones. Smoldering combustion is an exothermic reaction (net energy producing) converting carbon compounds and an oxidant (e.g., oxygen in air) to carbon dioxide, water, and energy. Thus, following ignition, the smoldering combustion reaction can continue in a self‐sustaining manner (i.e., no external energy or added fuel input following ignition) as the heat generated by the reacting contaminants is used to preheat and initiate combustion of contaminants in adjacent areas, propagating a combustion front through the contaminated zone provided a sufficient flux of air is supplied. The STAR technology has applicability across a wide‐range of hydrocarbons in a variety of hydrogeologic settings; however, there are limitations to its use. Impacted soils must be permeable enough to allow a sufficient flux of air to the combustion front and there exists a minimum required concentration of contaminants such that the soils contain sufficient fuel for the reaction to proceed in a self‐sustaining manner. Further limitations, as well as lessons learned and methods to mitigate these limitations, are presented through a series of case studies. In summary, the successful implementation of STAR will result in >99 percent reduction in contaminant concentrations in treated areas, limited residual contaminant mass, reduced groundwater contaminant mass flux which can be addressed through monitored natural attenuation; and an enhanced site exit strategy, reduced lifecycle costs, and reduced risk. ©2016 Wiley Periodicals, Inc. 相似文献
528.
One of the most significant junctures in natural resource planning and management in recent years has been the emergence of community-based natural resource management (CBNRM). The central focus of CBNRM is the environment, of course. However, it explicitly considers the local economy and community as well. It is a highly participatory approach to local, place-based projects, programs and policies aimed simultaneously at environmental and community health. This paper is an attempt to shed light on what happens in the local economy and community as a result of pursuing a CBNRM strategy. Oregon has been in the vanguard in putting CBNRM into operation. A key example is the state's experience with local watershed councils and the state agency that supports them, the Oregon Watershed Enhancement Board (OWEB). Drawing from a larger study of Oregon's watershed councils, we ask and answer the questions: ‘What direct contribution do watershed councils make to the local economies of Oregon?’; ‘Do watershed councils contribute to ‘civic engagement’ in Oregon?’ and ‘Do they enhance individuals' and communities’ capacity to engage in public issues beyond watershed council activities?’ 相似文献
529.
Wet Strength and Water Resistance of Modified Soy Protein Adhesives and Effects of Drying Treatment 总被引:7,自引:0,他引:7
Zhikai Zhong X. Susan Sun Donghai Wang Jo A. Ratto 《Journal of Polymers and the Environment》2003,11(4):137-144
Soy protein isolate (SPI) was modified using sodium dodecyl sulfate (SDS) and guanidine hydrochloride (GuHCl). Adhesion performance of the modified SPI on fiberboard was studied. The Water-soluble mass of the modified SPI adhesives was examined following modified ASTM D5570. The SDS-modified SPI containing 91% protein had a water-soluble mass of 1.7%. To be considered a water-resistant adhesive, the water-soluble mass of adhesive should be less than 2%. The wet shear strength test showed 100% cohesive failure within fiberboard, indicating that the modified SPI has good water resistance. The effect of drying treatment on adhesion performance of the SDS-modified SPI on fiberboard was then investigated. Drying treatment significantly affected the final adhesion performance. Shear strength did not change much, but the percentage of cohesive failure within fiberboard increased markedly as drying temperature increased. All the unsoaked, soaked, and wet specimens glued by the adhesives treated at 70° or 90°C had 100% cohesive failure within fiberboard. Viscosity also increased greatly with an increase in drying temperature. This information will be useful in developing low-cost adhesive processing system in the future. 相似文献
530.
Martin M. Karpiscak Kennith E. Foster Susan B. Hopf John M. Bancroft Peter J. Warshall 《Journal of the American Water Resources Association》1994,30(2):219-227
ABSTRACT: Water hyacinth (Eichhornia crassipes L.) has shown to be effective in the treatment of municipal wastewater in a pilot study begun in January 1989 by the Pima County Wastewater Management Department and researchers associated with The University of Arizona's Office of Arid Lands Studies in the Sonoran Desert near Tucson. The influent pumped into the pilot facility's six raceways (ponds) typically has been treated secondary effluent diverted from a conventional treatment facility, although primary effluent from the same facility also has been treated. The Secondary Influent Treatment System has met the Arizona Department of Environmental Quality (ADEQ) tertiary standard for BOD5 and TSS of 10 mg/l for every month of its operation since March 1990; the Primary Influent Treatment System met the ADEQ secondary standard for BOD5 and TSS of 30 mg/1 for most of the 10 months it was in operation. 相似文献