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231.
Adjusting the timing of hatching to changing environmental conditions has fitness costs in blue tits
Edward?KluenEmail author Maaike?E.?de?Heij Jon?E.?Brommer 《Behavioral ecology and sociobiology》2011,65(11):2091-2103
After laying the first egg, a bird can, to a certain extent, adjust the hatching date of the brood to environmental conditions.
However, costs of this adjustment have remained largely unexplored. We studied potential costs of hatching delay in a population
of blue tits in southern Finland. We explored the factors underlying hatching delay and investigated the association between
hatching delay, clutch hatchability and female body condition. Finally, we reciprocally cross-fostered a large number of broods
irrespective of their experienced hatching delay to address possible downstream effects of hatching delay on developmental
parameters in offspring. We found that hatching delay was associated with early laying dates and low mean temperatures during
the egg-laying phase. Furthermore, we found evidence that delayed hatching negatively affected the breeding performance. Hatchability
of the clutch was lowered and the breeding female was energetically impaired, resulting in smaller clutch sizes, lower female
body mass at hatching and lowered survival of nestlings reared in nests that had experienced a long hatching delay. In addition,
delayed hatching had a significant negative effect on the body mass of nestlings prior to fledging. However, ultimately we
did not find evidence that delayed hatching affected survival of the breeding female nor recruitment of fledglings in the
local breeding population. Our study demonstrates that environmental conditions during egg laying can have lasting effects
throughout the breeding and nestling phase. Furthermore, our results emphasize the importance of energetic tradeoffs by breeding
females during the early breeding phase to manage reproductive costs. 相似文献
232.
Hansen S Nieboer E Sandanger TM Wilsgaard T Thomassen Y Veyhe AS Odland JØ 《Journal of environmental monitoring : JEM》2011,13(8):2143-2152
The objective of this study was to investigate changes in the levels of toxic and essential elements in maternal blood during pregnancy and subsequently. A subset of 211 pregnant women from the North Norwegian Mother-and-Child Study was included. Blood samples were collected during the 2(nd) trimester (P1) and postpartum (day 3, P2; and 6 weeks, P3) in different regions of northern Norway, and were analyzed for a suite of 10 selected elements. The latter feature three general but distinct concentration patterns across the three collection periods, namely: progressive increase [Group 1: As, Cd (non-smokers only), Mn, Pb and Zn]; V-shaped, with a minimum at P2 [Group 2: Cd (smokers), Hg, Mo and Se]; and downward V, with a maximum at P2 [Group 3: Co and Cu]. These trends are interpreted in the context of underlying metabolic, hematological and physiological changes that occur in mothers, as well the biochemistry and accumulation preferences of these elements within the whole blood compartment and breast milk. Implications for biomonitoring strategies are discussed. In a multivariable analysis of the P1 data, fish consumption was a robust positive predictor for Hg (p < 0.02), As (p < 0.01) and Se (p ≤ 0.001) blood concentrations, multivitamin intake for Se (p < 0.001), and parity for Co (p < 0.002); age reached significance only for Hg (p < 0.001). An inverse association was observed between parity and Hg (p < 0.05). For the other elements, predictor patterns were not evident. 相似文献
233.
Elie Gaget Alison Johnston Diego Pavón-Jordán Aleksi S. Lehikoinen Brett K. Sandercock Alaaeldin Soultan Luka Božič Preben Clausen Koen Devos Cristi Domsa Vitor Encarnação Sándor Faragó Niamh Fitzgerald Teresa Frost Clemence Gaudard Lívia Gosztonyi Fredrik Haas Menno Hornman Tom Langendoen Christina Ieronymidou Leho Luigujõe Włodzimierz Meissner Tibor Mikuska Blas Molina Zuzana Musilová Jean-Yves Paquet Nicky Petkov Danae Portolou Jozef Ridzoň Laimonas Sniauksta Antra Stīpniece Norbert Teufelbauer Johannes Wahl Marco Zenatello Jon E. Brommer 《Conservation biology》2022,36(4):e13877
Protected area networks help species respond to climate warming. However, the contribution of a site's environmental and conservation-relevant characteristics to these responses is not well understood. We investigated how composition of nonbreeding waterbird communities (97 species) in the European Union Natura 2000 (N2K) network (3018 sites) changed in response to increases in temperature over 25 years in 26 European countries. We measured community reshuffling based on abundance time series collected under the International Waterbird Census relative to N2K sites’ conservation targets, funding, designation period, and management plan status. Waterbird community composition in sites explicitly designated to protect them and with management plans changed more quickly in response to climate warming than in other N2K sites. Temporal community changes were not affected by the designation period despite greater exposure to temperature increase inside late-designated N2K sites. Sites funded under the LIFE program had lower climate-driven community changes than sites that did not received LIFE funding. Our findings imply that efficient conservation policy that helps waterbird communities respond to climate warming is associated with sites specifically managed for waterbirds. 相似文献
234.
235.
Zara Richmond Ron Fleischer Maya Chopra Jason Pinner Mario D'Souza Yelena Fridgant Jonathan Hyett 《黑龙江环境通报》2017,37(10):975-982
Objective: The aim of this study was to (1) examine the psychological impact of non-invasive prenatal testing (NIPT) in women with a high-risk (≥1 : 300) and low-risk (≤1 : 301) result on combined first trimester screening (cFTS) and (2) to examine factors influencing anxiety and decision-making in both risk populations. Method: Questionnaires and structured interviews were administered to low (n = 50) and high (n = 63) risk women at the time of NIPT blood draw (point A) and again at least 1 week after receiving their NIPT result (point B). Anxiety levels were measured at these two time points using the State–Trait Anxiety Inventory. Results: Both high-risk and low-risk cFTS groups demonstrated similar intrinsic (trait) anxiety levels (36 ± 10 vs 35 ± 10; p = 0.70). High-risk women had significantly higher levels of state anxiety at point A than low-risk women (42 ± 11 vs 36 ± 11; p < 0.01). Both groups had a statistically significant reduction (p < 0.01), to similar final levels of state anxiety at point B (30 ± 11 vs 29 ± 8; p = 0.61). Conclusion: Women receiving a high-risk result on cFTS have higher levels of state anxiety than their low-risk counterparts. Following a low-risk NIPT result, the anxiety levels in both populations are reduced to similar levels. © 2017 John Wiley & Sons, Ltd. 相似文献
236.
Stephen E. Lewis Jon E. Brodie Zoë T. Bainbridge Ken W. Rohde Aaron M. Davis Bronwyn L. Masters Mirjam Maughan Michelle J. Devlin Jochen F. Mueller Britta Schaffelke 《Environmental pollution (Barking, Essex : 1987)》2009,157(8-9):2470-2484
The runoff of pesticides (insecticides, herbicides and fungicides) from agricultural lands is a key concern for the health of the iconic Great Barrier Reef, Australia. Relatively low levels of herbicide residues can reduce the productivity of marine plants and corals. However, the risk of these residues to Great Barrier Reef ecosystems has been poorly quantified due to a lack of large-scale datasets. Here we present results of a study tracing pesticide residues from rivers and creeks in three catchment regions to the adjacent marine environment. Several pesticides (mainly herbicides) were detected in both freshwater and coastal marine waters and were attributed to specific land uses in the catchment. Elevated herbicide concentrations were particularly associated with sugar cane cultivation in the adjacent catchment. We demonstrate that herbicides reach the Great Barrier Reef lagoon and may disturb sensitive marine ecosystems already affected by other pressures such as climate change. 相似文献
237.
238.
Carla Ximena Salinas Jon Mendieta 《Mitigation and Adaptation Strategies for Global Change》2013,18(5):659-672
Climate change will further increase the risk of desertification, which is already affecting large areas of the world. Many countries are making investments for the implementation of mitigation and adaptation strategies to combat desertification. The long term effectiveness of these strategies necessarily require a socioeconomic return for its sustainability. The main goal of our paper is to assess the relation between the mitigation and adaptation investments and the socio-economy of the rural population. The area of study is located in north-central Chile. The northern regions are mostly composed by arid land, which can be considered as a marginal area for agriculture. The area formed by the southern regions is optimal for the agricultural activity which is characterized by an industrialized agriculture with and increased use of technology. The indicators we have used for our study are the following: the Investments provided by the Chilean Agriculture Livestock and Forestry (ALF) promotion agencies, the ALF Gross Domestic Product (GDP) and the Population Employed in ALF. The results show that the relationship between the investments and the socioeconomy varies among the regions analyzed. Investments are positively correlated (P?≤?0.05) with the ALF GDP and the labor in ALF in the northern regions, but do not seem to be directly related to labor in ALF in the southern regions (P?≥?0.05). Therefore, our conclusion is that the Investments are significantly relevant for the agricultural activity in the arid northern regions, while in the southern regions they have no direct impact on the labor in ALF. 相似文献
239.
Martin W. Doyle Emily H. Stanley Jon M. Harbor 《Journal of the American Water Resources Association》2002,38(6):1567-1579
ABSTRACT: There is a pressing need for tools to predict the rates, magnitudes, and mechanisms by which sediment is removed from a reservoir following dam removal, as well as for tools to predict where this sediment will be deposited downstream and how it will impact downstream channel morphology. In the absence of adequate empirical data, a good initial approach is to examine the impacts of dam removal within the context of the geomorphic analogies of channel evolution models and sediment waves. Channel changes at two dam breaching sites in Wisconsin involved a succession of channel forms and processes consistent with an existing channel evolution model. Sediment transported downstream after removal of other dams suggests that reservoir sediment may be translated downstream either as a distinct wave or gradually eroded away. More extensive data collection on existing dam removals is warranted before undertaking the removal of a large number of dams. However, if removal is to proceed based on current knowledge, then geomorphic analogies can be used as the foundation for sediment management and stabilization schemes. 相似文献
240.