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Carlos Palacín Juan C. Alonso Carlos A. Martín Javier A. Alonso 《Conservation biology》2017,31(1):106-115
Many bird populations have recently changed their migratory behavior in response to alterations of the environment. We collected data over 16 years on male Great Bustards (Otis tarda), a species showing a partial migratory pattern (sedentary and migratory birds coexisting in the same breeding groups). We conducted population counts and radio tracked 180 individuals to examine differences in survival rates between migratory and sedentary individuals and evaluate possible effects of these differences on the migratory pattern of the population. Overall, 65% of individuals migrated and 35% did not. The average distance between breeding and postbreeding areas of migrant individuals was 89.9 km, and the longest average movement of sedentary males was 3.8 km. Breeding group and migration distance had no effect on survival. However, mortality of migrants was 2.4 to 3.5 times higher than mortality of sedentary birds. For marked males, collision with power lines was the main cause of death from unnatural causes (37.6% of all deaths), and migratory birds died in collisions with power lines more frequently than sedentary birds (21.3% vs 6.3%). The percentage of sedentary individuals increased from 17% in 1997 to 45% in 2012. These results were consistent with data collected from radio‐tracked individuals: The proportion of migratory individuals decreased from 86% in 1997–1999 to 44% in 2006–2010. The observed decrease in the migratory tendency was not related to climatic changes (temperatures did not change over the study period) or improvements in habitat quality (dry cereal farmland area decreased in the main study area). Our findings suggest that human‐induced mortality during migration may be an important factor shaping the migration patterns of species inhabiting humanized landscapes. 相似文献
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《组织行为杂志》2017,38(7):1016-1037
This experimental switching replications design study examined the effectiveness of a brief mindfulness‐based training intervention that included a one‐hour mindfulness‐based workshop followed by 13 days of behavioral self‐monitoring (BSM) in an attempt to reduce work–family conflict. The intervention increased participants' mindfulness and decreased work‐to‐family conflict, but did not reduce family‐to‐work conflict. In addition, those who participated in BSM reported greater mindfulness, less work‐to‐family conflict, and less family‐to‐work conflict than did those who did not participate in BSM. Theoretical and practical implications, as well as future research directions, are discussed. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
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MATTHEW SOMMERVILLE E.J. MILNER‐GULLAND MICHAEL RAHAJAHARISON JULIA P.G. JONES 《Conservation biology》2010,24(6):1488-1498
Abstract: Despite the growing interest in conservation approaches that include payments for environmental services (PES), few evaluations of the influence of such interventions on behaviors of individuals have been conducted. We used self‐reported changes in six legal and illegal forest‐use behaviors to investigate the way in which a PES for biodiversity conservation intervention in Menabe, Madagascar, influenced behavior. Individuals (n =864) from eight intervention communities and five control communities answered questions on their forest‐use behaviors before and after the intervention began, as well as on their reasons for changing and their attitudes to various institutions. The payments had little impact on individuals’ reported decisions to change behaviors, but it had a strong impact on individuals’ attitudes. Payments appeared to legitimize monitoring of behaviors by the implementing nongovernmental organization (NGO), but did not act as a behavioral driver in their own right. Although there were no clear differences between changes in behaviors in the intervention and control communities, the intervention did influence motivations for change. Fear of local forest associations and the implementing NGO were strong motivators for changing behavior in communities with the PES intervention, whereas fear of the national government was the main reason given for change in control communities. Behavioral changes were most stable where fear of local organizations motivated the change. Our results highlight the interactions between different incentives people face when making behavioral decisions and the importance of considering the full range of incentives when designing community‐based PES interventions. 相似文献
566.
E.I. Vanguelova S. Benham A.J. Moffat T. Nisbet N. Barsoum F. Bochereau S. Broadmeadow P. Taylor 《Environmental pollution (Barking, Essex : 1987)》2010,158(5):1857-1869
Long term trend analysis of bulk precipitation, throughfall and soil solution elemental fluxes from 12 years monitoring at 10 ICP Level II forest sites in the UK reveal coherent national chemical trends indicating recovery from sulphur deposition and acidification. Soil solution pH increased and sulphate and aluminium decreased at most sites. Trends in nitrogen were variable and dependant on its form. Dissolved organic nitrogen increased in bulk precipitation, throughfall and soil solution at most sites. Nitrate in soil solution declined at sites receiving high nitrogen deposition. Increase in soil dissolved organic carbon was detected - a response to pollution recovery, changes in soil temperature and/or increased microbial activity. An increase of sodium and chloride was evident - a possible result of more frequent storm events at exposed sites. The intensive and integrated nature of monitoring enables the relationships between climate/pollutant exposure and chemical/biological response in forestry to be explored. 相似文献
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采用田间试验方法,进行了生物稻壳粉、生物稻草粉2种生物有机除草剂对水田杂草的防效试验。结果表明,2种生物有机除草剂对水田杂草均有不同程度的防效,其中生物稻壳粉防效最好、经济效益最高,生物稻草粉防效和经济效益次之。该试验研究为生产有机水稻提供了新的除草方法。 相似文献
568.
传统的U型通风工作面上隅角瓦斯积聚现象经常出现,严重制约着矿井正常生产能力的有效发挥,对矿井安全生产造成重大威胁。基于前人对采空区非均质多孔介质气体运移理论的研究,采用Fluent软件数值模拟研究了U型和上隅角埋管条件下U型通风系统的静压力场和瓦斯浓度场。研究结果表明:在相同的模型参数条件下,U型通风容易造成上隅角瓦斯积聚,上隅角瓦斯超限问题十分严重;采空区5m处埋管,治理上隅角瓦斯积聚的效果欠佳,达不到安全开采的条件;15m处埋管可以较好的解决上隅角瓦斯超限问题,工作面没有出现瓦斯积聚现象,工作面和回风巷的瓦斯浓度始终处于1%以下;25m处埋管的效果与15m基本相同,没有表现出更好的瓦斯治理效果。综合数值模拟的结果,确定了上隅角埋管抽放采空区瓦斯的理想抽放位置为距离地板垂高1.2m、沿走向深入采空区15m处。 相似文献
569.
环境监测工作是环境保护工作的基础工作,在新的形势下,如何做好环境监测工作,是环保工作必须面对的一个重要课题。本文通过总结研究淮北市在环境监测工作中一些富有创造性的做法和所取得的成效,经验,提出了一些有独立见解的工作思路和建议,对广大环保工作者特别是环境监测工作者,有一定的借鉴意义。 相似文献
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