Modeling the environmental controls on tree water use at different temporal scales

Acknowledgements This study is part of the first author’s PhD projects in 2010–2014, co-funded by the National Centre for Groundwater Research and Training in Australia and the China Scholarship Council. We give thanks to Zijuan Deng and Xiang Xu for their assistance in the field. Constructive comments and suggestion from the anonymous reviewers are appreciated for significant improvement of the manuscript.

Tackling wicked environmental problems : the discourse and its influence on praxis in Scotland

Peer reviewed

Lipid analytic of environmental and cultural samples

Membrane lipids of marine planktonic archaea have provided unique insights into archaeal ecology and paleoceanography. However, past studies of archaeal lipids in suspended particulate matter (SPM) and sediments mainly focused on a small class of fully saturated glycerol dibiphytanyl glycerol tetraether (GDGT) homologues identified decades ago. The apparent low structural diversity of GDGTs is in strong contrast to the high diversity of metabolism and taxonomy among planktonic archaea. Furthermore, adaptation of archaeal lipids in the deep ocean remains poorly constrained. We report the archaeal lipidome in SPM from diverse oceanic regimes. We extend the known inventory of planktonic archaeal lipids to include numerous unsaturated archaeal ether lipids (uns-AELs). We further reveal i) different thermal regulations and polar headgroup compositions of membrane lipids between the epipelagic (<= 100 m) and deep (> 100 m) populations of archaea; ii) stratification of unsaturated GDGTs with varying redox conditions; and iii) enrichment of tetra-unsaturated archaeol and fully saturated GDGTs in epipelagic and deep oxygenated waters, respectively. Such stratified lipid patterns are consistent with the typical distribution of archaeal phylotypes in marine environments. We thus provide an ecological context for GDGT-based paleoclimatology and bring about the potential use of uns-AELs as biomarkers for planktonic Euryarchaeota. This article is protected by copyright. All rights reserved.

Organic-walled dinoflagellate cysts and environmental analysis of surface sediments from the Northwest African upwelling area

In order to examine the spatial distribution of organic-walled dinoflagellate cysts (dinocysts) in recent sediments related to environmental conditions in the water column, thirty-two surface sediment samples from the NW African upwelling region (20-32°N) were investigated. Relative abundances of the dinocyst species show distinct regional differences allowing the separation of four hydrographic regimes. (1) In the area off Cape Ghir, which is characterized by most seasonal upwelling and river discharge, Lingulodinium machaerophorum strongly dominates the associations which are additionally characterized by cysts of Gymnodinium nolleri, cysts of Polykrikos kofoidii and cysts of Polykrikos schwartzii. (2) Off Cape Yubi, a region with increasing perennial upwelling, L. machaerophorum, Brigantedinium spp., species of the genus Impagidinium and cysts of Protoperidinium stellatum occur in highest relative abundances. (3) In coastal samples between Cape Ghir and Cape Yubi, Gymnodinium catenatum, species of the genus Impagidinium, Nematosphaeropsis labyrinthus, Operculodinium centrocarpum, cysts of P. stellatum and Selenopemphix nephroides determine the species composition. (4) Off Cape Blanc, where upwelling prevails perennially, and at offshore sites, heterotrophic dinocyst species show highest relative abundances. A Redundancy Analysis reveals fluvial mud, sea surface temperature and the depth of the mixed layer in boreal spring (spring) as the most important parameters relating to the dinocyst species association. Dinocyst accumulation rates were calculated for a subset of samples using well-constrained sedimentation rates. Highest accumulation rates with up to almost 80.000 cysts cm**-2 ky**-1 were found off Cape Ghir and Cape Yubi reflecting their eutrophic upwelling filaments. A Redundancy Analysis gives evidence that primary productivity and the input of fluvial mud are mostly related to the dinocyst association. By means of accumulation rate data, quantitative cyst production of individual species can be considered independently from the rest of the association, allowing autecological interpretations. We show that a combined interpretation of relative abundances and accumulation rates of dinocysts can lead to a better understanding of the productivity conditions off NW Africa.

(Table 1) Radiocarbon results from this study

The Indonesian Arc represents the subduction of the Indian-Australian plate beneath Asia. It has been the scene of catastrophic tectonic activity, including the recent 2004 M=9.1 Aceh earthquake and resulting Indian Ocean tsunami. We have dated planktonic forams associated with historic tephras (Tambora, 1815 and Krakatau, 1883) in marine sediment cores to determine radiocarbon reservoir ages for 2 locations along the arc. Our best estimates for 19th century regional reservoir corrections (DeltaR) are +90 ± 40 yr for surface-dwelling species and +220 ± 40 yr for mixed planktic assemblages containing some upper thermocline species, but scatter in the data suggests that past surface reservoir ages may have varied by about ±100 yr. We used the results of this study to investigate a proposed very large AD 535 eruption at or near Krakatau. We find no evidence for ash from such an eruption, and although this is negative evidence, we consider it sufficiently strong to rule out any possibility that one took place.

Big Data Analytics for Earth Sciences: the EarthServer approach

Big Data Analytics is an emerging field since massive storage and computing capabilities have been made available by advanced e-infrastructures. Earth and Environmental sciences are likely to benefit from Big Data Analytics techniques supporting the processing of the large number of Earth Observation datasets currently acquired and generated through observations and simulations. However, Earth Science data and applications present specificities in terms of relevance of the geospatial information, wide heterogeneity of data models and formats, and complexity of processing. Therefore, Big Earth Data Analytics requires specifically tailored techniques and tools. The EarthServer Big Earth Data Analytics engine offers a solution for coverage-type datasets, built around a high performance array database technology, and the adoption and enhancement of standards for service interaction (OGC WCS and WCPS). The EarthServer solution, led by the collection of requirements from scientific communities and international initiatives, provides a holistic approach that ranges from query languages and scalability up to mobile access and visualization. The result is demonstrated and validated through the development of lighthouse applications in the Marine, Geology, Atmospheric, Planetary and Cryospheric science domains.

Big Data Analytics for Earth Sciences: the EarthServer approach

Big Data Analytics is an emerging field since massive storage and computing capabilities have been made available by advanced e-infrastructures. Earth and Environmental sciences are likely to benefit from Big Data Analytics techniques supporting the processing of the large number of Earth Observation datasets currently acquired and generated through observations and simulations. However, Earth Science data and applications present specificities in terms of relevance of the geospatial information, wide heterogeneity of data models and formats, and complexity of processing. Therefore, Big Earth Data Analytics requires specifically tailored techniques and tools. The EarthServer Big Earth Data Analytics engine offers a solution for coverage-type datasets, built around a high performance array database technology, and the adoption and enhancement of standards for service interaction (OGC WCS and WCPS). The EarthServer solution, led by the collection of requirements from scientific communities and international initiatives, provides a holistic approach that ranges from query languages and scalability up to mobile access and visualization. The result is demonstrated and validated through the development of lighthouse applications in the Marine, Geology, Atmospheric, Planetary and Cryospheric science domains.

Influence of environmental conditions on the age, hatch dates, and growth of juvenile Atlantic menhaden in the Choptank River, MD

Since 1993 Atlantic menhaden has experienced sustained low juvenile production (recruitment) in the Chesapeake Bay. Factors controlling growth, abundance, and mortality of larval and juvenile menhaden change throughout ontogeny such that larval growth rates could carry over to juvenile growth and survival. The effects of winter thermal conditions on the hatch dates and growth of larval and juvenile Atlantic menhaden in Atlantic shelf and Chesapeake Bay habitats were examined using otolith (ear-stone) increment analyses and growth models. For 2010-2013, truncated hatch-date distributions provided evidence for a winter recruitment bottleneck in Atlantic menhaden caused by cold temperatures. Hatch-dates of surviving juveniles were skewed towards warmer months for years characterized by colder temperatures. Reduced larval growth rates, influenced by reduced temperature and food availability, carried over to juvenile growth rates. A growing degree-day model performed well in simulating observed juvenile growth rates in the Choptank River tributary of Chesapeake Bay.

Perceptions of climate change, environmental variability and the role of agricultural adaptation strategies by small-scale farmers in Africa: the case of Mwanga district in Northern Tanzania

Abstract The potential impacts of climate change and environmental variability are already evident in most parts of the world, which is witnessing increasing temperature rates and prolonged flood or drought conditions that affect agriculture activities and nature-dependent livelihoods. This study was conducted in Mwanga District in the Kilimanjaro region of Tanzania to assess the nature and impacts of climate change and environmental variability on agriculture-dependent livelihoods and the adaptation strategies adopted by small-scale rural farmers. To attain its objective, the study employed a mixed methods approach in which both qualitative and quantitative techniques were used. The study shows that farmers are highly aware of their local environment and are conscious of the ways environmental changes affect their livelihoods. Farmers perceived that changes in climatic variables such as rainfall and temperature had occurred in their area over the period of three decades, and associated these changes with climate change and environmental variability. Farmers’ perceptions were confirmed by the evidence from rainfall and temperature data obtained from local and national weather stations, which showed that temperature and rainfall in the study area had become more variable over the past three decades. Farmers’ knowledge and perceptions of climate change vary depending on the location, age and gender of the respondents. The findings show that the farmers have limited understanding of the causes of climatic conditions and environmental variability, as some respondents associated climate change and environmental variability with social, cultural and religious factors. This study suggests that, despite the changing climatic conditions and environmental variability, farmers have developed and implemented a number of agriculture adaptation strategies that enable them to reduce their vulnerability to the changing conditions. The findings show that agriculture adaptation strategies employ both planned and autonomous adaptation strategies. However, the study shows that increasing drought conditions, rainfall variability, declining soil fertility and use of cheap farming technology are among the challenges that limit effective implementation of agriculture adaptation strategies. This study recommends further research on the varieties of drought-resilient crops, the development of small-scale irrigation schemes to reduce dependence on rain-fed agriculture, and the improvement of crop production in a given plot of land. In respect of the development of adaptation strategies, the study recommends the involvement of the local farmers and consideration of their knowledge and experience in the farming activities as well as the conditions of their local environment. Thus, the findings of this study may be helpful at various levels of decision making with regard to the development of climate change and environmental variability policies and strategies towards reducing farmers’ vulnerability to current and expected future changes.

Environmental assessment of proton exchange membrane fuel cell platinum catalyst recycling

International audience

(Appendix A) Sedimentation rate, geochemical and environmental magnetic proxies of the samples of the Metochia section, on the island of Gavdos, south of Crete

The upper Tortonian Metochia marls on the island of Gavdos provide an ideal geological archive to trace variations in Aegean sediment supply as well as changes in the North African monsoon system. A fuzzy-cluster analysis on the multiproxy geochemical and rock magnetic dataset of the astronomically tuned sedimentary succession shows a dramatic shift in the dominance of 'Aegean tectonic' clusters to 'North African climate' clusters. The tectonic signature, traced by the starvation of the Cretan sediment, now enables to date the late Tortonian basin foundering on Crete, related to the tectonic break-up of the Aegean landmass, at c. 8.2 Ma. The synchronous decrease in the North African climate proxies is interpreted to indicate a change in the depositional conditions of the sink rather than a climatic change in the African source. This illustrates that interpretations of climate proxies require a multiproxy approach which also assesses possible contributions of regional tectonism.

MIGRATION PATTERNS AMONG YOUNG ADULTS IN THE UNITED STATES: ENVIRONMENTAL, SOCIAL, AND ECONOMIC EXPLANATIONS

Young adult migration is a key factor in community development. The goal of this paper is to study what kinds of places attract young adults and what kinds are losing them. Linear regression is conducted to analyze what place-specific factors explain migration patterns among young adults. These factors include economic, social, and environmental variables. This study finds that social and environmental factors are just as important as economic ones. Specifically, employment in the arts increases young adult net migration. Environmental variables, for example, natural amenities and protected federal lands are particularly important in rural settings in attracting young adults. These findings suggest that policy makers interested in attracting and retaining young adults should pay closer attention to social and environmental factors and consider creating more opportunities for arts employment in general. For rural areas, improving the attractiveness of natural amenities and better protection of federal lands is also recommended.

Characterisation of indoor air organic pollutants in Brisbane

The occurrence and levels of airborne polycyclic aromatic hydrocarbons and volatile organic compounds in selected non-industrial environments in Brisbane have been investigated as part of an integrated indoor air quality assessment program. The most abundant and most frequently encountered compounds include, nonanal, decanal, texanol, phenol, 2-ethyl-1-hexanol, ethanal, naphthalene, 2,6-tert-butyl-4-methyl-phenol (BHT), salicylaldehyde, toluene, hexanal, benzaldehyde, styrene, ethyl benzene, o-, m- and pxylenes, benzene, n-butanol, 1,2-propandiol, and n-butylacetate. Many of the 64 compounds usually included in the European Collaborative Action method of TVOC analysis were below detection limits in the samples analysed. In order to extract maximum amount of information from the data collected, multivariate data projection methods have been employed. The implications of the information extracted on source identification and exposure control are discussed.