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11.
Erica M. Tennenhouse Robert B. Weladji Øystein Holand Knut H. Røed Mauri Nieminen 《Behavioral ecology and sociobiology》2011,65(2):287-295
In polygynous species, males devote considerable effort to reproduction during the rut. Both the number of females in the
mating group and the ratio of sexually mature males to sexually mature females [adult sex ratio (ASR)] are expected to affect
the amount of effort a male devotes to reproductive activities. We predicted the reproductive effort of dominant male reindeer,
measured as relative mass loss, proportions of active reproductive behaviors, and frequencies of agonistic behaviors would
(1) increase with an increasing number of females in the mating group and eventually level off, and (2) exhibit a dome shape
with respect to ASR in the mating group. We tested these predictions using 12 years of data collected from semi-domesticated
reindeer in northern Finland. We found a positive relationship between relative mass loss and the mean number of females in
the mating group for mature, but not young males. The relationship between the proportion of active reproductive behaviors
performed by mature males and the mean number of females in the group was quadratic while agonistic behaviors of mature males
increased with the increasing female group size. We also found that active reproductive behaviors decreased with a rising
mating group ASR for mature males; whereas, young males performed more agonistic behaviors as group ASR increased. Our results
point to age-specific patterns of mass loss and activity during the mating season. They also indicate that both the number
of females and ASR in the mating group are important factors in determining the level of reproductive effort of dominant male
reindeer. 相似文献
12.
Nieminen TM Derome J Helmisaari HS 《Environmental pollution (Barking, Essex : 1987)》1999,106(1):129-137
Bulk precipitation and stand throughfall were collected during 1992-96 at distances of 0.5, 4 and 8 km from the Harjavalta Cu-Ni smelter, southwestern Finland. The amounts of heavy metals (Cu, Ni, Zn, Fe) and mineral nutrients in bulk precipitation and throughfall were highest at 0.5 km. Although the canopy coverage was low at 0.5 km, the amounts of heavy metals intercepted by the canopy were extremely high. The proportion of foliar leaching relative to the wash-off of dry deposition from the needle surfaces decreased on moving towards the smelter for all elements, except for K. The high rate of K leaching from the needle tissues close to the smelter demonstrated that the K throughfall flux has been greatly altered by the heavy pollution load. 相似文献
13.
Raija Ilmarinen Harri Lindholm Kari Koivistoinen Petteri Helistén 《International journal of occupational safety and ergonomics》2004,10(3):215-226
This job-related experiment investigated physiological strain in subjects wearing impermeable chemical protective suit systems (CPSSs) weighing about 28 kg. Two types of CPSSs were studied: the self-contained breathing apparatus was carried either inside or outside the suit. Eight healthy and physically fit male firefighter instructors aged 32 to 45 years volunteered for the study. The test drill, performed at a dry, windless ta of 40 degrees C, was divided into 2 consecutive work sessions of 14.5 min (a 20-min rest between) including typical operational work tasks. Considerable thermal and maximal cardiovascular strain and intense subjective discomfort measured in the firefighters emphasize the need to limit working time in hot conditions to only 10-12 min while wearing CPSSs. The present results indicate that the exceptionally heavy physical load and psychological stress during operations in chemical emergencies must be considered in the assessment of the cardiovascular capacity of ageing firefighters using CPSSs. 相似文献
14.
Mika Nieminen Marjo Palviainen Sakari Sarkkola Ari Laurén Hannu Marttila Leena Finér 《Ambio》2018,47(5):523-534
Drained peatlands are an important source of forest biomass in boreal regions and ditch network maintenance (DNM) operations may be needed to restore the drainage functions of ditches. By reviewing the available literature, as well as utilizing an existing hydrological model and analyzing the characteristics of eroded sediments, we assessed the impacts of DNM on runoff and exports of suspended solids (SS), dissolved organic carbon (DOC), nitrogen (N), and phosphorus (P). In general, DNM had minor impact on runoff and dissolved N and P, and it decreased rather than increased DOC exports. To increase the understanding of the hydrochemical impacts of DNM, future research should focus on the characteristics of SS and particulate nutrient exports. A major gap in knowledge is also the very limited regional representativeness of the available studies. High erosion risk in the ditches reaching the mineral soil below peat should be acknowledged when planning mitigation measures. 相似文献
15.
Which comes first,organizational culture or performance? A longitudinal study of causal priority with automobile dealerships
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Anthony S. Boyce Levi R. G. Nieminen Michael A. Gillespie Ann Marie Ryan Daniel R. Denison 《组织行为杂志》2015,36(3):339-359
Prior research supports a link between organizational culture and performance but generally falls short of establishing causality or determining the direction of a culture–performance (C‐P) relationship. Using data collected from 95 franchise automobile dealerships over 6 years, we studied longitudinal culture–performance relationships to determine whether culture or performance has causal priority, or alternatively, whether a reciprocal relationship exists. Results from cross‐lagged panel analyses indicate that culture “comes first,” consistently predicting subsequent ratings of customer satisfaction and vehicle sales. Furthermore, the positive effect of culture on vehicle sales is fully mediated by customer satisfaction ratings. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
16.
Enchytraeids are regarded as keystone soil organisms in forest ecosystems. Their abundance and biomass fluctuate widely. Predicting the consequences of anthropogenic disturbances requires an understanding of the mechanisms underlying enchytraeid population dynamics. Here I develop a simple model, which predicts that the type of dynamics is controlled by resource input rate. If fungal resource input is a discrete event once a year, an exponential growth phase is followed by starvation and sharp decline of enchytraeid abundance. Model simulations with three different forcing functions were compared to field data. Initial parameter values were obtained from various independent sources, and parameters were estimated by minimizing the residual sum of squares. The best fitting model with resource addition once a year explained 39% of the variation in enchytraeid biomass over an 8-year study period. Further, variation in rainfall explained 59% of the variation in R2 of the exponential phase models, which is also an index of the stability of population size-structure. The results emphasize the importance of resource limitation for enchytraeid population dynamics and support the hypothesis that the mortality during the decline phase is size-dependent. 相似文献
17.
Rantavaara A Wallin H Hasunen K Härmälä K Kulmala H Latvio E Liskola K Mustonen I Nieminen I Tainio R 《Journal of environmental radioactivity》2005,83(3):305-317
An expert group was established in 2001 representing various organisations and authorities responsible for primary production, food processing, the distribution and consumption of foodstuffs, food safety and availability, catering and extension services, nature conservation, research into environmental impacts, and the media. The aim was to strengthen networking and improve the stakeholder response to accidental radioactive contamination of rural areas through participation in the FARMING network project. A hypothetical contamination of a large milk-producing area provided a suitable framework for evaluation of actions ensuring clean feeding of dairy cows during grazing. The following year the group received a compilation of rural countermeasures and waste disposal methods, described by the STRATEGY project. The robust, uncomplicated approach of the evaluation meetings was fruitful and efficient, and the multidisciplinary group was capable of taking shared views on various measures after updating their knowledge together. High priority was given to measurements of radioactivity and the provision of information and advice to a wider audience. 相似文献
18.
Ø. Holand R. B. Weladji K. H. Røed H. Gjøstein J. Kumpula J.-M. Gaillard M. E. Smith M. Nieminen 《Behavioral ecology and sociobiology》2006,59(5):682-688
The manipulation of the sex ratio and age structure in many managed ungulate populations calls for a better understanding
of their potential consequences on females’ condition and behavior during rut. During 1996–2002, we manipulated the male age
structure and male percentage (nine treatments during 7 years) within an experimental herd of semidomestic reindeer (Rangifer tarandus) and investigated their influence on both the body mass change and the behavior of females during rut. On average, the females
lost body mass (−0.95±SE 0.18 kg) during rut, which we contend to reflect somatic costs. The females’ losses increased as
the percentage of male decreased, but this was certainly ascribed to one treatment with high male percentage (27.7%) as compared
to the others (ranging from 3.9 to 12.2%). Female losses were highest for treatments including both young and adult males
as compared to only adult or only young males, and higher for treatments including only young compared to only adult males.
This is supported by (1) the higher female harassment frequency when females are exposed to only young or a mixture of young
and adult males as compared to only adults, (2) the higher female harassment frequency by young males as compared to adults
in the mixed treatments, and (3) the reduced females’ feeding activity in treatments including both young and adult males.
We conclude that the male age structure during rut will influence the females’ behavior and mass change and may have implications
for females’ life history and for population dynamics. 相似文献
19.
Nieminen TM 《Journal of environmental monitoring : JEM》2004,6(11):888-896
The contribution of soil Cu and Ni pollution to the poor vitality and growth rate of Scots pine growing in the vicinity of a Cu-Ni smelter was investigated in two manipulation experiments. In the first manipulation, Cu-Ni smelter-polluted soil cores were transported from a smelter-pollution gradient to unpolluted greenhouse conditions. A 4-year-old pine seedling was planted in each core and cultivated for a 17-month period. In the second manipulation, pine seedlings from the same lot were cultivated for the same 17-month period in a quartz sand medium containing increasing doses of copper sulfate, nickel sulfate, and a combination of both. The variation in the biomass growth of the seedlings grown in the smelter-polluted soil cores was very similar to that of mature pine stands growing along the same smelter-pollution gradient in the field. In addition, the rate of Cu and Ni exposure explained a high proportion of the biomass growth variation, and had an effect on the Ca, K, and Mg status of the seedlings. According to the lethal threshold values determined on the basis of the metal sulfate exposure experiments, both the Cu and Ni content of the 0.5 km smelter-polluted soil cores were high enough to cause the death of most of the seedlings. The presence of Cu seemed to increase Ni toxicity. 相似文献
20.
Climate targets call for novel policy measures to facilitate widespread adoption of low-carbon solutions and innovations. The literature on socio-technical systems argues that experimentation has a prominent role in enabling sustainability transition. Experiments represent ways of testing new ideas and methods across a wide range of policy fields. Governance experiments in particular can support accelerated diffusion of new solutions, because they integrate policy with innovations. Here, types of success factors in the implementation of governance experiments to mitigate climate change are examined. Statistical analysis of sustainability innovations in the 28 European Union countries indicates that the types of success factors in governance experiments differ from those of product and social experiments. Governance experimentation is more positioned within socio-technical regimes than in strategic niches. These results suggest that governance experiments may indeed provide new transition opportunities towards low-carbon societies. 相似文献