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161.
Graham W. Prescott  William J. Sutherland  Daniel Aguirre  Matthew Baird  Vicky Bowman  Jake Brunner  Grant M. Connette  Martin Cosier  David Dapice  Jose Don T. De Alban  Alex Diment  Julia Fogerite  Jefferson Fox  Win Hlaing  Saw Htun  Jack Hurd  Katherine LaJeunesse Connette  Felicia Lasmana  Cheng Ling Lim  Antony Lynam  Aye Chan Maung  Benjamin McCarron  John F. McCarthy  William J. McShea  Frank Momberg  Myat Su Mon  Than Myint  Robert Oberndorf  Thaung Naing Oo  Jacob Phelps  Madhu Rao  Dietrich Schmidt‐Vogt  Hugh Speechly  Oliver Springate‐Baginski  Robert Steinmetz  Kirk Talbott  Maung Maung Than  Tint Lwin Thaung  Salai Cung Lian Thawng  Kyaw Min Thein  Shwe Thein  Robert Tizard  Tony Whitten  Guy Williams  Trevor Wilson  Kevin Woods  Alan D. Ziegler  Michal Zrust  Edward L. Webb 《Conservation biology》2017,31(6):1257-1270
Political and economic transitions have had substantial impacts on forest conservation. Where transitions are underway or anticipated, historical precedent and methods for systematically assessing future trends should be used to anticipate likely threats to forest conservation and design appropriate and prescient policy measures to counteract them. Myanmar is transitioning from an authoritarian, centralized state with a highly regulated economy to a more decentralized and economically liberal democracy and is working to end a long‐running civil war. With these transitions in mind, we used a horizon‐scanning approach to assess the 40 emerging issues most affecting Myanmar's forests, including internal conflict, land‐tenure insecurity, large‐scale agricultural development, demise of state timber enterprises, shortfalls in government revenue and capacity, and opening of new deforestation frontiers with new roads, mines, and hydroelectric dams. Averting these threats will require, for example, overhauling governance models, building capacity, improving infrastructure‐ and energy‐project planning, and reforming land‐tenure and environmental‐protection laws. Although challenges to conservation in Myanmar are daunting, the political transition offers an opportunity for conservationists and researchers to help shape a future that enhances Myanmar's social, economic, and environmental potential while learning and applying lessons from other countries. Our approach and results are relevant to other countries undergoing similar transitions.  相似文献   
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In avian species whose chicks show facultative siblicide, attacks increase with food deprivation. In species that show obligate siblicide, this causal relationship is not expected, but no test has been made. When we composed artificial pairs of young brown boobies, Sula leucogaster (an obligately siblicidal species), and supplied variable amounts of food to the older nestlings in each pair, food ingestion was related to the most intense form of attack, pushes, which can cause death by expelling the broodmate from the nest. The less food an older nestling ingested, the more time it spent active and the greater its rate and absolute frequency of pushes, and the more often it expelled its nestmate. Hence, deficient food provision to older nestlings could precipitate siblicidal expulsion of broodmates. Younger nestmates were aggressive too, and the more they were pushed and expelled, the more they pecked. Aggression of senior brown-booby broodmates may be flexible and food sensitive in order to optimize the timing of siblicide or to make siblicide weakly facultative.Communicated by R. Gibson  相似文献   
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The photodegradation of the herbicides atrazine and ametryn with visible light in aerated neutral aqueous solutions and 5, 10, 15, 20-tetrakis (2,6-dichloro-3-sulfophenyl) porphyrin or 5, 10, 15, 20-tetrakis (4-sulfophenyl) porphyrin as sensitizers are reported for the first time. Our findings show that the degradation percentage reached 30% for atrazine and 63% for ametryn. The final photoproducts were characterized as dealkylated s-triazines. Photolysis of the pesticides in the presence of a singlet oxygen quencher showed only a minor contribution of this type of mechanism, while a bimolecular quenching reaction between the triplet state of the sensitizer and the pesticides is excluded by flash photolysis studies. It is proposed that the mechanism may involve the formation of a superoxide radical anion from the triplet state of the sensitizer and molecular oxygen, followed by a radical decomposition pathway. Selected article from 1st International Meeting on Photochemistry, Photocatalysis and Environmental Applications, Agadir, 2006, organised by Prof. Dr. Ait Ichou, University Ibn Zohr, Agadir, Morocco  相似文献   
167.
The function of hatching asynchrony in the blue-footed booby   总被引:3,自引:0,他引:3  
The blue-footed booby (Sula nebouxii) commonly hatches two eggs 4 days apart; then the senior (first-hatched) chick aggressively dominates the other and sometimes kills it. Two hypotheses explaining the function of the hatching interval were tested by creating broods with synchronous hatching: the facultative brood reduction hypothesis of Lack (1954) and the sibling rivalry reduction hypothesis of Hahn (1981). The results contradicted most predictions of both hypotheses: synchronous broods formed an aggressive hierarchy similarly to asynchronous broods (controls), and subordinate chicks grew poorly (Fig. 1) and died frequently, similarly to junior chicks in control broods. However, compared with synchronous broods, asynchronous broods showed less aggression (Fig. 2), diminished food allocation to subordinate chicks (Fig. 3) and less total food consumption (30% fewer feeds at age 0–10 days). These behavioral comparisons took into account the different ages of chicks in different treatments. The results suggest that natural asynchrony makes brood reduction more efficient and decreases the costs of sibling aggression to parents, in terms of their future survival or fecundity, as proposed by Mock and Ploger (1987). Further, in exaggeratedly asynchronous broods (8-day hatch interval) junior chicks suffered more aggression (Fig. 4) and grew more slowly than junior chicks in control broods. This result supports the hypothesis of optimal hatch asynchrony of Mock and Ploger (1987).  相似文献   
168.
The Nottingham Cycle Friendly Employers Project studied the effectiveness of measures to promote cycling to work by eight large city employers under the 1995 governmentfunded Cycle Challenge. Progress was monitored by 'before' and 'after' surveys, by examination of the measures, and by discussions with the employers. Overall cycling awareness and activity were increased by the project: 42% of employees said their cycle commuting had increased. The main influences, about equally, were providing workplace cycling facilities, a house or job move making cycling more attractive, and heightened awareness of the importance of regular exercise for health. The most welcomed and best used measures were secure cycle parking, showering and changing facilities, and cycle purchase loans.  相似文献   
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A number of distinct definitions ofsustainable agriculture have been proposed. In this paper we criticize two such definitions, primarily for conflating sustainability with other objectives such as economic viability and ecological integrity. Finally, we propose and defend a definition which avoids our objections to the other definitions.  相似文献   
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