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381.
Daily and seasonal variations in dry and wet atmospheric nitrogen fluxes have been studied during four campaigns between 2004 and 2006 at a coastal site of the Southern North Sea at De Haan (Belgium) located at coordinates of 51.1723° N and 3.0369° E. Concentrations of inorganic N-compounds were determined in the gaseous phase, size-segregated aerosol (coarse, medium, and fine), and rainwater samples. Dissolved organic nitrogen (DON) was quantified in rainwater. The daily variations in N-fluxes of compounds were evaluated with air-mass backward trajectories, classified into the main air-masses arriving at the sampling site (i.e., continental, North Sea, and Atlantic/UK/Channel).The three, non-episodic campaigns showed broadly consistent fluxes, but during the late summer campaign exceptionally high episodic N-deposition was observed. The average dry and wet fluxes for non-episodic campaigns amounted to 2.6 and 4.0 mg N m?2 d?1, respectively, whereas during the episodic late summer period these fluxes were as high as 5.2 and 6.2 mg N m?2 d?1, respectively.Non-episodic seasons/campaigns experienced average aerosol fluxes of 0.9–1.4 mg N m?2 d?1. Generally, the contribution of aerosol NH4+ was more significant in the medium and fine particulate fractions than that of aerosol NO3?, whereas the latter contributed more in the coarse fraction, especially in continental air-masses. During the dry mid-summer campaign, the DON contributed considerably (~15%) to the total N-budget.Exceptionally high episodic aerosol-N inputs have been observed for the late summer campaign, with especially high deposition rates of 3.6 and 2.9 mg N m?2 d?1 for Atlantic/UK/Channel and North Sea-continental (mixed) air-masses, respectively. During this pollution episode, the flux of NH4+ was dominating in each aerosol fraction/air-mass, except for coarse continental aerosols. High deposition of gaseous-N was also observed in this campaign with an average total N-flux of 2–2.5-times higher than in other campaigns.  相似文献   
382.
Environmental Science and Pollution Research - International investment is needed in every economy, and every economy is expected to grow and attract investment. Despite the need of the above in...  相似文献   
383.
Regional Environmental Change - Protection of natural or semi-natural ecosystems is an important part of societal strategies for maintaining biodiversity, ecosystem services, and achieving overall...  相似文献   
384.
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   
385.
Inclusive recycling is the inspiring slogan of a project relying on a cross-sector (public–private–civil society) partnership implemented in Latin America with the objective to improve the socioeconomic conditions of recyclers. Through a qualitative study in Santiago de Chile, this paper seeks to understand how inclusive inclusive recycling is, by assessing how organised recyclers perceive the goals, the process, and the outcomes of this project. The main findings converge in observing a general low inclusion of recyclers, but they also enable to decompose the notion of inclusion into three dimensions: “inclusive goals” refers to the extent to which the goals of the recyclers are taken into account when designing the collaboration project; “inclusive process” refers to the extent to which recyclers are involved in the process of implementing the project; and “inclusive outcomes” refers to the capacity of the partnership to acknowledge the achievements of recyclers organisations before (and during) the project and to take into account the ongoing local dynamics when evaluating the project. These findings contribute to better understand the position and challenges of recyclers in this type of partnership and more generally to shed light on the potential power imbalance in waste management cross-sector partnerships.  相似文献   
386.
387.
Chemical communication appears to be the primary mode of information transfer among woodland salamanders of the genus Plethodon. These pheromones have been shown to convey a wide variety of information, and are used to establish territorial boundaries. Responses to pheromones can include changes in both behavior and energy consumption. The ability of Ozark zigzag salamanders, Plethodon angusticlavius, to detect the sex of a conspecific through chemical substrate markings has not been assessed. In addition, some populations of P. angusticlavius are naturally infected with the ectoparasitic mite Hannemania eltoni. Parasitism can impact both the behavior and metabolism of the host as well as the behavior of others towards the parasitized individual. We examined whether sex and parasitism of the pheromone donor and receiver influenced behavioral and metabolic responses in P. angusticlavius. In laboratory trials, behavior of P. angusticlavius was influenced by the sex and parasite load of the pheromone donors and receivers. Behavioral responses were also influenced by whether the receiver was in its own territory or in the territory of the pheromone donor. Metabolic responses were not affected by the sex or parasite load of the pheromone donor, but males had higher metabolic rates than females, even after adjusting for differences in body size. Overall, our study indicates that both sex and parasitism can be detected via pheromones in this species, and the nature of the response depends on residency status, sex, and parasite load of the receiver.  相似文献   
388.
389.
An ‘I see you’ (ISY) prey–predator signal can co-evolve when such a signal benefits both prey and predator. The prey benefits if, by producing the signal, the predator is likely to break off an attack. The predator benefits if it is informed by the signal that the prey is aware of its presence and can break off what is likely to be an unsuccessful and potentially costly hunt. Because the signal and response co-evolve in two species, the behaviour underlying an ISY signal is expected to have a strong genetic component and cannot be entirely learned. An example of an ISY signal is the ‘shimmering’ behaviour performed by Asian hive bee workers in the presence of their predator Vespa velutina. To test the prediction that bee–hornet signalling is heritable, we let honey bee workers of two species emerge in an incubator so that they had never been exposed to V. velutina. In Apis cerana, the shimmering response developed 48 h post-emergence, was strong after 72 h and increased further over 2 weeks. In contrast, A. mellifera, which has evolved in the absence of Asian hornets, did not produce the shimmering signal. In control tests, A. cerana workers exposed to a non-threatening butterfly did not respond with the shimmering signal.  相似文献   
390.
Double-choice experiments with three adult males of the little golden-mantled flying fox, Pteropus pumilus, and ten adult greater musky fruit bats, Ptenochirus jagori (both Megachiroptera: Pteropodidae), demonstrate that they are able to discriminate accurately between an empty dish and a dish containing fruits of one of several species by odour alone. Tests were run using fruits of six fruit species for Pteropus pumilus and five fruit species for Ptenochirus jagori. The fruit species used are known to be consumed in the wild by Ptenochirus jagori and are, with two exceptions, species of the natural rain-forest habitat. This is the first study to show that fruit bats are also able to assess the ripeness of a fruit exclusively by its odour. The bats preferred ripe over unripe fruits of the same species. Thus, both Pteropus pumilus and Ptenochirus jagori can not only locate fruits by their odour but can also discriminate between ripe and unripe fruits of the same species by olfaction. The results confirm and expand earlier findings on the role of olfactory cues in the orientation of foraging pteropodids.  相似文献   
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