Managing multiple catchment demands for sustainablewater use and ecosystem service provision

Ensuring water, food and energy security for a growing world population represents a 21st century catchment management challenge. Failure to recognise the complexity of interactions across ecosystem service provision can risk the loss of other key environmental and socioeconomic benefits from the natural capital of catchment systems. In particular, the ability of soil and water to meet human needs is undermined by uncertainties around climate change effects, ecosystem service interactions and conflicting stakeholder interests across catchments. This critical review draws from an extensive literature to discuss the benefits and challenges of utilising an ecosystem service approach for integrated catchment management (ICM). State-of-the-art research on ecosystem service assessment, mapping and participatory approaches is evaluated and a roadmap of the key short- and longer-term research needs for maximising landscape-scale ecosystem service provision from catchments is proposed. © 2017 by the authors. Licensee MDPI, Basel, Switzerland

Quantifying stakeholder understanding of an ecosystem service trade-off

Sustainable management of global natural resources is challenged by social and environmental drivers, adding pressure to ecosystem service provision in many regions of the world where there are competing demands on environmental resources. Understanding trade-offs between ecosystem services and how they are valued by different stakeholder groups is therefore critical to maximise benefits and avoid conflict between competing uses. In this study we developed a novel participatory trade-off experiment to elicit the perception of 43 participants, from across four key stakeholder groups, working in land and water management (Environmental Regulators, Farming Advisors, Water Industry Staff and Catchment Scientists). Using the Production Possibility Frontier (PPF) concept, we quantified stakeholder assessment of both the shape and the uncertainty around the PPF in a trade-off between agricultural intensity and the ecological health of freshwater systems. The majority of stakeholder groups selected threshold and logistic decay trade-off curves to describe the relationship of the trade-off, and estimated the uncertainty around the curves to be intermediate or large. The views of the four stakeholder groups differed significantly regarding how they estimated stakeholder trade-off prioritisation; the largest difference in perspectives was identified between Environmental Regulators and Farm Advisors. The methodology considered the cultural, socio-economic and institutional specificities of an ecosystem service interaction and identified potential sources of conflict but also possible solutions for win-win opportunities to explore and share understanding between stakeholders. Valuing stakeholder knowledge as a form of expert data and integrating this into participatory decision-making processes for land and water management thus contributes considerable value beyond traditional approaches to ecosystem service assessments

Efficiency of self-cleaning properties in wheat (Triticum aestivum L.)

An experimental study was carried out to assess the efficiency of self-cleaning properties of three wheat cultivars and their potential in the protection against Blumeria graminis f. sp. tritici, a fungus that causes powdery mildew. Leaf samples with intact epicuticular structure were compared to such with wiped wax crystals. Contact angles were determined and the surfaces were subjected to a standardized contamination test with hydrophobic fluorescence powder. Another set of samples was inoculated with conidia of B. graminis and, after various time intervals, exposed to artificial fog or rain. For the intact surfaces of all cultivars contact angles of about 165° were measured. It is therefore suggested that wheat should be termed superhydrophobic. The wiping of the wax crystals led to a significant decrease of contact angles. This fact underlines the importance of surface roughness for achieving extreme water-repellency. In the standardized contamination test significantly more particles remained on the wiped surfaces than on those who had been left intact. This result was ascribed to increased adhesion on the smoothed samples.The inoculation with subsequent precipitation revealed a significantly better removal effect of conidia from intact than from wiped surfaces. This was irrespective of the wheat cultivar. In general, conidia were more effectively removed by rain than by fog. This was probably due to the higher kinetic energy and the greater amount of water when using rain. If fog application was delayed by 3 hours a higher percentage of conidia remained on the surface. As possible causes are discussed increased adhesion by conidia secretions or the development of primary germ tubes.Despite its highly efficient self-cleaning properties proved here, wheat is frequently infected by Blumeria graminis. We conclude that the high water content of the mildew conidia, the ability of Blumeria graminis to germinate at very low humidities and its rapid irreversible adhesion are effective adaptations in order to overcome the barrier of a superhydrophobic self-cleaning surface

Rapid Characterisation of Stakeholder Networks in Three Catchments Reveals Contrasting Land-Water Management Issues

Catchments are socio-ecological systems integrating land, water and people with diverse roles and views. Characterising stakeholder networks and their levels of influence and interaction within catchments can help deliver more effective land and water management. In this study, we combined stakeholder analysis and social network methods to provide a novel stakeholder-mapping tool capable of identifying interactions among the land and water management communities across three contrasting study catchments. The overarching aim was to characterise the influence of different stakeholders involved in catchment management based on the perceptions of participants from four key stakeholder groups (Environmental Regulators, Water Industry Practitioners, the Farm Advisor Community, and Academics). A total of 43 participants identified 28 types of specific catchment management stakeholder groups with either core or peripheral importance to our three case study catchments. Participants contributed 490 individual scores relating to the perceived influence of these different stakeholder groups and categorised whether this influence was positive, negative or neutral for the management of catchment resources. Local Government, Farmers and Environmental Regulators were perceived to have the greatest level of influence. Social network analysis further determined which stakeholders were most commonly connected in all of the study catchments and hence formed the core of stakeholder networks in each catchment. Comparing outputs from the analysis of three contrasting river catchments, as well as between participants from four key stakeholder groups allowed identification of which stakeholders were more central to the catchment management networks. Such analyses could help facilitate effective communication within land and water management stakeholder networks by targeting highly connected opinion leaders or promoting peer learning via distinct catchment subgroups

Catchment-Scale Participatory Mapping Identifies Stakeholder Perceptions of Land and Water Management Conflicts

Competing socioecological demands and pressures on land and water resources have the potential to increase land use conflict. Understanding ecosystem service provisioning and trade-offs, competing land uses, and conflict between stakeholder groups in catchments is therefore critical to inform catchment management and the sustainable use of natural resources. We developed a novel stakeholder engagement methodology that incorporates participatory conflict mapping in three catchments with a short questionnaire to identify the perceptions of 43 participants from four key land and water management stakeholder groups: environmental regulators, water industry practitioners, the farm advisor community, and academics. The participatory mapping exercise produced heat maps of perceived conflict and land use competition, providing spatial detail of the complex combination of land use issues faced by catchment managers. Distinct, localised hotspots were identified in areas under pressure from flooding, abstraction, and urbanisation; as well as more dispersed issues of relevance at the landscape scale, such as from farming, forestry, energy production, and tourism. Subsequent regression modelling linked perceived conflict to land cover maps and identified coastal, urban, and grassland areas as the most likely land cover types associated with conflict in the study catchments. Our approach to participatory conflict mapping provides a novel platform for catchment management and can facilitate increased cooperation among different catchment stakeholders. In turn, land and water management conflicts can be recognised and their underlying drivers and likely solutions identified in an effort to better manage competing demands on catchment resources

The Hidden Sexuality of Alexandrium Minutum: An Example of Overlooked Sex in Dinoflagellates

Dinoflagellates are haploid eukaryotic microalgae in which rapid proliferation causes dense blooms, with harmful health and economic effects to humans. The proliferation mode is mainly asexual, as the sexual cycle is believed to be rare and restricted to stressful environmental conditions. However, sexuality is key to explaining the recurrence of many dinoflagellate blooms because in many species the fate of the planktonic zygotes (planozygotes) is the formation of resistant cysts in the seabed (encystment). Nevertheless, recent research has shown that individually isolated planozygotes in the lab can enter other routes besides encystment, a behavior of which the relevance has not been explored at the population level. In this study, using imaging flow cytometry, cell sorting, and Fluorescence In Situ Hybridization (FISH), we followed DNA content and nuclear changes in a population of the toxic dinoflagellate Alexandrium minutum that was induced to encystment. Our results first show that planozygotes behave like a population with an “encystment-independent” division cycle, which is light-controlled and follows the same Light:Dark (L:D) pattern as the cycle governing the haploid mitosis. Resting cyst formation was the fate of just a small fraction of the planozygotes formed and was restricted to a period of strongly limited nutrient conditions. The diploid-haploid turnover between L:D cycles was consistent with two-step meiosis. However, the diel and morphological division pattern of the planozygote division also suggests mitosis, which would imply that this species is not haplontic, as previously considered, but biphasic, because individuals could undergo mitotic divisions in both the sexual (diploid) and the asexual (haploid) phases. We also report incomplete genome duplication processes. Our work calls for a reconsideration of the dogma of rare sex in dinoflagellates.Versión del edito

Conversion of self-assembled monolayers into nanocrystalline graphene: Structure and electric transport

Graphene-based materials have been suggested for applications ranging from nanoelectronics to nanobiotechnology. However, the realization of graphene-based technologies will require large quantities of free-standing two-dimensional (2D) carbon materials with tuneable physical and chemical properties. Bottom-up approaches via molecular self-assembly have great potential to fulfil this demand. Here, we report on the fabrication and characterization of graphene made by electron-radiation induced cross-linking of aromatic self-assembled monolayers (SAMs) and their subsequent annealing. In this process, the SAM is converted into a nanocrystalline graphene sheet with well defined thickness and arbitrary dimensions. Electric transport data demonstrate that this transformation is accompanied by an insulator to metal transition that can be utilized to control electrical properties such as conductivity, electron mobility and ambipolar electric field effect of the fabricated graphene sheets. The suggested route opens broad prospects towards the engineering of free-standing 2D carbon materials with tuneable properties on various solid substrates and on holey substrates as suspended membranes.Comment: 30 pages, 5 figure

Effect of food concentration and type of diet on Acartia survival and naupliar development

We have performed life table experiments to investigate the effects of different food types and concentrations on the larval development and survival up to adulthood of Acartia tonsa. The food species offered comprised a wide taxonomic spectrum: the pigmented flagellates Isochrysis galbana, Emiliania huxleyi, Rhodomonas sp., Prorocentrum minimum, the diatom Thalassiosira weissflogii, grown on medium offering enriched macronutrient concentrations and the ciliate Euplotes sp. initially cultured on Rhodomonas. For the ciliate species, also the functional response was studied. In order to avoid limitation by mineral nutrients, food algae have been taken from the exponential growth phase of the nutrient replete cultures. The suitability of Rhodomonas as a food source throughout the entire life cycle was not a surprise. However, in contrast to much of the recent literature about the inadequacy or even toxicity of diatoms, we found that also Thalassiosira could support Acartia-development through the entire life cycle. On the other hand, Acartia could not complete its life cycle when fed with the other food items, Prorocentrum having adverse effects even when mixed with Rhodomonas and Thalassiosira. Isochrysis well supported naupliar survival and development, but was insufficient to support further development until reproduction. With Emiliania and Euplotes, nauplii died off before most of them could reach the first copepodite stages. Acartia-nauplii showed a behavioral preference for Euplotes-feeding over diatom feeding, but nevertheless Euplotes was an insufficient diet to complete development beyond the naupliar stages

Resting spores of the freshwater diatoms Acanthoceras and Urosolenia

Diatom resting spores are a widespread, but sometimes misconstrued component of siliceous microfossil assemblages. We illustrate and discuss resting spore morphology found in populations of Acanthoceras and Urosolenia , two widely distributed freshwater genera. Taxonomic status of these genera and the potential paleolimnologic interpretation of resting spores are discussed.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/43094/1/10933_2004_Article_BF00680035.pd

Comment letters to the National Commission on Commission on Fraudulent Financial Reporting, 1987 (Treadway Commission) Vol. 1

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