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21.
Parental care may be costly to parents because it decreases resources allocated to self-maintenance and may thus reduce survival
and future reproductive success. An inter-sexual conflict may exist in animals with obligatory bi-parental care, such as birds
of prey, in which females incubate and brood, whereas males provision food for their families. We analysed 29 years of data
(1981–2009) from a study population of Tengmalm’s owls Aegolius funereus in western Finland to examine the occurrence and timing of brood desertion and sequential polyandry, and recorded a total
of 1,123 monogamous and 12 polyandrous females. These data were supplemented with the 29-year nationwide Finnish ringing data,
which included 11,590 monogamous and 20 polyandrous females. The 12 polyandrous females started egg-laying in their two nests
at intervals of 54–68 days (mean 60 days), thus deserting their first broods when the age of oldest young averaged 21 days.
Thirty-two polyandrous females re-mated and raised a second brood at a median distance of 4.5 km (range 1–196 km). These females
produced 79% more eggs, 93% more hatchlings and 73% more fledglings than did females that laid simultaneously but remained
monogamous. Our results show that not only males, but also females of altricial species with bi-parental care can increase
their fitness by deserting their first brood when it will be cared for by the males. Earlier studies have shown that male
owls can increase their lifetime reproductive success by simultaneous polygyny, and we suggest that an inter-sexual “tug-of-war”
over bi-parental care exists in Tengmalm’s owls. 相似文献
22.
This is the first study seasonally applying Sphagnum papillosum moss bags and vertical snow samples for monitoring atmospheric pollution.Moss bags,exposed in January,were collected together with snow samples by early March 2012 near the Harjavalta Industrial Park in southwest Finland.Magnetic,chemical,scanning electron microscopy-energy dispersive X-ray spectroscopy(SEM-EDX),K-means clustering,and Tomlinson pollution load index(PLI)data showed parallel spatial trends of pollution dispersal for both materials.Results strengthen previous findings that concentrate and slag handling activities were important(dust)emission sources while the impact from Cu–Ni smelter's pipe remained secondary at closer distances.Statistically significant correlations existed between the variables of snow and moss bags.As a summary,both methods work well for sampling and are efficient pollutant accumulators.Moss bags can be used also in winter conditions and they provide more homogeneous and better controlled sampling method than snow samples. 相似文献
23.
T. H. Tengku Ismail H. Juahir A. Z. Aris Sharifuddin M. Zain Armi Abu Samah 《Environment, Development and Sustainability》2016,18(3):739-762
This paper provides a detailed analysis of the local community response to a newly installed rare earth (RE) refinery facility and the factors underlying its acceptance. House-to-house interviews, using structured questionnaire, were conducted in 2013 (N = 370). Results show that the community was divided into deciding whether they agreed with the presence of the facility, 41.36 % (for) and 41.62 % (against). The remaining fraction of the community was undecided, which made up 17.03 % of the total respondents. This paper identifies six significant predictors of risk acceptance: gender, education status, place of residence, Factor 1 (variables—perception of safety, concern on effects, and trust in the operators), Factor 2 (variables—social and individual benefits), and Factor 3 (variables—no confidence in government). This study gives insights on how the public respond to potential hazardous facilities and highlights the need for policy makers to consider public sentiment which can interfere with further expansion of the RE industry. 相似文献
24.
Jessica A. Salo David M. Theobald Thomas C. Brown 《Journal of the American Water Resources Association》2016,52(3):632-647
Riparian zones in semi‐arid, mountainous regions provide a disproportionate amount of the available wildlife habitat and ecosystem services. Despite their importance, there is little guidance on the best way to map riparian zones for broad spatial extents (e.g., large watersheds) when detailed maps from field data or high‐resolution imagery and terrain data are not available. Using well‐established accuracy metrics (e.g., kappa, precision, computational complexity), we evaluated eight methods commonly used to map riparian zones. Focusing on a semi‐arid, mountainous watershed, we found that the most accurate and robust method for mapping riparian zones combines data on upstream drainage area and valley topography. That method performed best regardless of stream order, and was most effective when implemented with fine resolution topographic and stream line data. Other commonly used methods to model riparian zones, such as those based on fixed‐width buffers, yielded inaccurate results. We recommend that until very‐high resolution (<1 m) elevation data are available at broad extents, models of riparian zones for semi‐arid mountainous regions should incorporate drainage area, valley topography, and quantify uncertainty. 相似文献
25.
Pirjo Peltonen-Sainio Tapio Salo Lauri Jauhiainen Heikki Lehtonen Elina Sievil?inen 《Ambio》2015,44(6):544-556
The Finnish agri-environmental program (AEP) has been in operation for 20 years with >90 % farmer commitment. This study aimed to establish whether reduced nitrogen (N) and phosphorus (P) use has impacted spring cereal yields and quality based on comprehensive follow-up studies and long-term experiments. We found that the gap between genetic yield potential and attained yield has increased after the AEP was imposed. However, many contemporary changes in agricultural practices, driven by changes in prices and farm subsidies, also including the AEP, were likely reasons, together with reduced N, but not phosphorus use. Such overall changes in crop management coincided with stagnation or decline in yields and adverse changes in quality, but yield-removed N increased and residual N decreased. Further studies are needed to assess whether all the changes are environmentally, economically, and socially sustainable, and acceptable, in the long run. The concept of sustainable intensification is worth considering as a means to develop northern European agricultural systems to combine environmental benefits with productivity.
Electronic supplementary material
The online version of this article (doi:10.1007/s13280-015-0637-9) contains supplementary material, which is available to authorized users. 相似文献26.
Armi Z Turki S Trabelsi E Ceredi A Riccardi E Milandri A 《Environmental monitoring and assessment》2012,184(8):5085-5095
The main diarrhetic shellfish toxins, okadaic acid (OA) and dinophysistoxin-1, 2 (DTX-2, 2) were detected by liquid chromatography-tandem mass spectrometry (LC-MS/MS) as pyrenacyl esters in clams (Ruditapes decussatus) collected in Tunis north lagoon from January 2007 to June 2008. Sample analyses by LC-MS/MS displayed OA and related congeners (DTX-2, 2) with a highest detected level of 21 μg OA eq/kg shellfish meat for the samples of January 2007. Nevertheless, all samples were MBA negative. During the study period, potentially toxic dinoflagellate Dinophysis sacculus was recorded all year, blooming at different times. Highest concentrations were recorded during January 2007 with 4.6?×?10(4) cells per liter and 4.10(4) cells per liter in the northern and southern districts, respectively. Results show that there is no significant correlation between D. sacculus densities in water column and diarrhetic shellfish poisoning (DSP) toxins concentrations unregistered in clams. These data reveal that DSP toxicity in clams of Tunis north lagoon is low according to European regulatory limit (160 μg OA eq/kg shellfish meat). However, a potential threat, in this area, is represented by DSP toxic species as D. sacculus and provides grounds for widen and reinforcing sanitary control of the phycotoxin measures in the region. 相似文献
27.
Salo S Verta M Malve O Korhonen M Lehtoranta J Kiviranta H Isosaari P Ruokojärvi P Koistinen J Vartiainen T 《Chemosphere》2008,73(10):1675-1683
Kymijoki, the fourth largest river in Finland, has been heavily polluted by pulp mill effluents as well as the chemical industry. Up to 24,000 ton of wood preservative, chlorophenol known as Ky-5, was manufactured in the upper reaches of the river, an unknown amount of which was discharged into the river between 1940 and 1984. Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) occurred as impurities in the final Ky-5 product. The PCDD/F concentrations and burden in the river sediments were studied and the transport of PCDD/Fs from contaminated sites downstream and into the Gulf of Finland in the Baltic Sea was estimated. More than 190 sediment cores were sampled to estimate the volume of contaminated sediments and the total PCDD/F burden. The transport of PCDD/Fs was estimated using sediment traps placed at several sites. The survey revealed that sediments in the river were heavily polluted by PCDD/Fs, the main toxic congener being 1,2,3,4,6,7,8-heptachlorodibenzofuran, a major contaminant in the Ky-5 product. The mean total concentration at the most polluted river site downstream from the main source was 42000 microg kg(-1) d.w. (106 microg I-TEQ kg(-1)). The elevated concentrations in the coastal region and the present estimated transport from the River Kymijoki confirm earlier assessments that the river is a major source of PCDD/F for the Gulf of Finland. 相似文献
28.
Vincenzo Penteriani María del Mar Delgado Anna Kuparinen Pertti Saurola Jari Valkama Eino Salo Jere Toivola Adrian Aebischer Raphaël Arlettaz 《Behavioral ecology and sociobiology》2014,68(5):743-747
Upon leaving their natal area, dispersers are confronted with unknown terrains. Species-specific perceptual ranges (i.e. the maximum distance from which an individual can perceive landscape features) play a crucial role in spatial movement decisions during such wanderings. In nocturnal animals that rely on vision, perceptual range is dramatically enhanced during moonlight, compared to moonless conditions. This increase of the perceptual range is an overlooked element that may be responsible for the successful crossing of unfamiliar areas during dispersal. The information gathered from 143 radio-tagged eagle owl Bubo bubo juveniles in Spain, Finland and Switzerland shows that, although the decision to initiate dispersal is mainly an endogenous phenomenon determined by the attainment of a given age (~6 months), dispersers leave their birthplace primarily under the best light conditions at night, i.e. when most of the lunar disc is illuminated. This sheds new light into the mechanisms that may trigger dispersal from parental territory. 相似文献