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101.
Manakorn Sukmak Worawidh Wajjwalku Julia Ostner Oliver Schülke 《Behavioral ecology and sociobiology》2014,68(7):1097-1108
In groups with multiple males, direct mate competition may select for the evolution of dominance hierarchies that sort males into a queue for access to fertile females. The priority-of-access (PoA) model proposed by Altmann in 1962 makes explicit predictions about the resulting paternity distribution based on an interaction between male dominance rank and the overlap of female receptive phases. Here, we investigated whether the logic of the PoA model predicted the distribution of paternity across ranks in a seasonal breeder with high reproductive synchrony over six consecutive mating seasons. We studied 18 males that resided in a group of wild Assamese macaques (Macaca assamensis) in their natural habitat at Phu Khieo Wildlife Sanctuary, Thailand, between 2006 and 2011 with 5 to 13 conceptions per season. We assessed whether mate guarding increased paternity success, described “short-term” deviations from predicted paternity distribution, and examined how these are related to the number of competitors and fertile females. We determined genetic paternity of 43 (93 %) offspring born into the study group and found reproductive skew to be relatively low with 29 % alpha male paternity in accordance with the high degree of female reproductive synchrony observed. Short-term deviations from expected paternity distribution over ranks were not explained by the number of resident males or the number of conceiving females or their interaction. Within the limits of this study, these results suggest that even if males cannot discern female fertile phases, if reproduction is seasonal, and if reproductive synchrony is high, males may also compete directly over access to females. 相似文献
102.
The colonization-extinction dynamics of many species are affected by the dynamics of their patches. For increasing our understanding of the metapopulation dynamics of sessile species confined to dynamic patches, we fitted a Bayesian incidence function model extended for dynamic landscapes to snapshot data on five epiphytic lichens among 2083 mapped oaks (dynamic patches). We estimate the age at which trees become suitable patches for different species, which defines their niche breadth (number of suitable trees). We show that the colonization rates were generally low, but increased with increasing connectivity in accordance with metapopulation theory. The rates were related to species traits, and we show, for the first time, that they are higher for species with wide niches and small dispersal propagules than for species with narrow niches or large propagules. We also show frequent long-distance dispersal in epiphytes by quantifying the relative importance of local dispersal and background deposition of dispersal propagules. Local stochastic extinctions from intact trees were negligible in all study species, and thus, the extinction rate is set by the rate of patch destruction (tree fall). These findings mean that epiphyte metapopulations may have slow colonization-extinction dynamics that are explained by connectivity, species traits, and patch dynamics. 相似文献
103.
Mario Mitov Georgi Hristov Elitsa Hristova Rashko Rashkov Marina Arnaudova Andreas Zielonka 《Environmental Chemistry Letters》2009,7(2):167-173
The complex performance of newly synthesized CoNiMnB electrodeposits in base-stabilized sodium borohydride solutions was examined.
The rate of hydrogen generation due to borohydride hydrolysis was determined at different temperatures. Activation energy
of approximately 33 kJ/mol was estimated, which is lower than the values reported for other catalysts. At electrochemical
conditions, there is a competition between borohydride hydrolysis and electrooxidation reactions. The electrooxidation of
borohydride takes place with low overpotentials at relatively high current densities. The long-term discharge at galvanostatic
conditions as well as possibilities for partial storage of generated hydrogen indicates potentials for application of studied
electrodeposits as anode material in direct borohydride fuel cells (DBFC). 相似文献
104.
Claudia Pahl-Wostl Christoph Schlumpf Martin Büssenschütt Andreas Schönborn Jan Burse 《Integrated Assessment》2000,1(4):267-280
Within the CLEAR project a new approach to integrated assessment modelling has been developed for the participatory integrated
assessment of regional climate change involving citizens' focus groups. The climate change decision problem was structured
by focusing separately on climate impacts and mitigation options. The attempt was made to link the different scales of the
problem from the individual to the global level. The abstract topic of climate change was related to options on the level
of a citizen's individual lifestyle. The option of a low energy society was emphasised in order to embed the climate change
decision problem in a wider range of societal concerns. Special emphasis was given to the characterisation and communication
of uncertainties. The chosen approach allows different kinds of uncertainties in one framework to be addressed. The paper
concludes with a summary of the experience made, and recommendations for the use of models in participatory integrated assessments.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
105.
Jürgens N Schmiedel U Haarmeyer DH Dengler J Finckh M Goetze D Gröngröft A Hahn K Koulibaly A Luther-Mosebach J Muche G Oldeland J Petersen A Porembski S Rutherford MC Schmidt M Sinsin B Strohbach BJ Thiombiano A Wittig R Zizka G 《Environmental monitoring and assessment》2012,184(2):655-678
The international, interdisciplinary biodiversity research project BIOTA AFRICA initiated a standardized biodiversity monitoring network along climatic gradients across the African continent. Due to an identified lack of adequate monitoring designs, BIOTA AFRICA developed and implemented the standardized BIOTA Biodiversity Observatories, that meet the following criteria (a) enable long-term monitoring of biodiversity, potential driving factors, and relevant indicators with adequate spatial and temporal resolution, (b) facilitate comparability of data generated within different ecosystems, (c) allow integration of many disciplines, (d) allow spatial up-scaling, and (e) be applicable within a network approach. A BIOTA Observatory encompasses an area of 1?km2 and is subdivided into 100 1-ha plots. For meeting the needs of sampling of different organism groups, the hectare plot is again subdivided into standardized subplots, whose sizes follow a geometric series. To allow for different sampling intensities but at the same time to characterize the whole square kilometer, the number of hectare plots to be sampled depends on the requirements of the respective discipline. A hierarchical ranking of the hectare plots ensures that all disciplines monitor as many hectare plots jointly as possible. The BIOTA Observatory design assures repeated, multidisciplinary standardized inventories of biodiversity and its environmental drivers, including options for spatial up- and downscaling and different sampling intensities. BIOTA Observatories have been installed along climatic and landscape gradients in Morocco, West Africa, and southern Africa. In regions with varying land use, several BIOTA Observatories are situated close to each other to analyze management effects. 相似文献
106.
107.
Today's large-scale poultry production is often accompanied by high concentrations of airborne microorganisms at working places. However, the microbial communities in those bioaerosols are rarely characterised. In this study, we investigated the bacterial population in bioaerosols from a duck hatchery by both cultivation based and molecular methods and compared the results. Depending on used media, concentrations of airborne culturable bacteria varied between 6 × 10(1) and 7 × 10(6) CFU per m(3) air. The corresponding total cell count of DAPI stained cells was 2 × 10(7) cells per m(3) air. 16S rRNA gene analyses of bacterial isolates and clone libraries revealed a low species richness in hatcheries air, respectively. More than 50% of bacterial isolates were phylogenetically most closely related to bacterial species of the risk group 2 (German TRBA). The sequence composition in clone libraries supported the result of cultivation based approaches, whereby sequences assigned to Staphylococcus, Acinetobacter and Enterococcus are the most common. The high concentration of airborne bacteria which are most closely related to species of potential health risk requires further detailed investigations for these bacterial species. 相似文献
108.
Jarmo Poikolainen Juha Piispanen Jouni Karhu Reijo Seppänen Eero Kubin 《Environmental monitoring and assessment》2014,186(7):4299-4307
This study measured heavy metal and nutrient concentrations of two feather mosses during the periods of dry storage. Samples (Hylocomium splendens, Pleurozium schreberi) were collected in the nationwide moss surveys carried out on the permanent sample plots of the 8th Finnish National Forest Inventory in 1985–86, 1990, 1995 and 2000. A small amount of each moss sample was analyzed soon after collection, and the remainder was dried and stored at the Paljakka environmental specimen bank (ESB). The 108 stored samples from 27 plots were reanalyzed in 2008. Concentrations of heavy metals (Cd, Cr, Cu, Fe, Ni, Pb, Zn) and nutrients (Ca, K, Mg, P) were determined and compared for each survey year. Overall, Fe, Pb and Cr concentrations decreased, and Cu concentrations increased significantly during storage. The greatest decrease was observed in samples from plots where their initial concentrations were the highest. Changes in the concentrations of Cd, Ni and Zn were less pronounced. The loss of heavy metals is likely due to drying when cell membranes rupture and some of the surface material is lost. K, P and, to some extent, Mg concentrations increased during storage, whereas Ca did not change significantly. Nutrient increase is probably due to their movement from older to younger growths during the initial phase of drying. Ca is mostly bound to cell walls and is not easily released. Results emphasize the importance of establishing the intended use of a stored moss prior to sampling, in order to select and optimize an appropriate storage technique. 相似文献
109.
110.
Organic pollutants in compost and digestate. Part 1. Polychlorinated biphenyls, polycyclic aromatic hydrocarbons and molecular markers 总被引:1,自引:0,他引:1
Brändli RC Bucheli TD Kupper T Furrer R Stahel WA Stadelmann FX Tarradellas J 《Journal of environmental monitoring : JEM》2007,9(5):456-464
In Europe, 9.3 x 10(6) t(dry weight (dw)) of compost and digestate are produced per year. Most of this is applied to agricultural land, which can lead to considerable inputs of organic pollutants, such as polychlorinated biphenyls (PCB) and polycyclic aromatic hydrocarbons (PAH) to soil. This paper presents an inventory of the pollutant situation in source-separated composts, digestates and presswater in Switzerland by a detailed analysis of over 70 samples. PCB concentrations ( summation PCB 28, 52, 101, 118, 138, 153, 180) were significantly higher in urban (median: 30 microg kg(-1)dw, n = 52) than in rural samples (median: 14 microg kg(-1)dw, n = 16). Together with low concentrations in general, this points to aerial deposition on compost input material as the major contamination pathway. Enantiomeric fractions of atropisometric PCB were close to racemic. Median PAH concentration was 3010 microg kg(-1)dw( summation 15PAH, n = 69), and one quarter of the samples exhibited concentrations above the relevant Swiss guide value for compost (4000 microg kg(-1)dw). The levels were influenced by the treatment process (digestate > compost), the season of input material collection (spring-summer > winter > autumn), the particle size (coarse-grained > fine-grained), and maturity (mature > less mature). The main source of PAH in compost was pyrogenic, probably influenced mainly by liquid fossil fuel combustion and some asphalt abrasion, as suggested by multiple linear regression. This study, together with a companion paper reporting on other organic contaminates including emerging compound classes, provides a starting point for a better risk-benefit estimation of the application of compost and digestate to agricultural soil in Switzerland. 相似文献