Role of light and photophysiological properties on phytoplankton succession during the spring bloom in the north-western Mediterranean Sea

This study aimed to determine the role of light on the succession of the phytoplankton community during the spring bloom in the northwestern Mediterranean Sea. To this end, three successive Lagrangian experiments were carried out between March and April 2003. The three experiments correspond to distinct phases of the bloom development (pre-bloom, bloom peak and post-bloom, respectively) and therefore to different trophic conditions. Phytoplankton (sampled on a daily scale) was grouped in size-based classes (pico and nano+micro) each of them were characterised in terms of chemotaxonomic composition, primary production and photophysiological properties. The phytoplankton community evolved with time changing in both size-class dominance and specie/group dominance within each size class. The bloom peak was characterised by highly dynamic condition (i.e. vertical mixing) and by the dominance of both small (pico) and large (nano and micro) diatoms, as a result of their capacity to photoacclimate to changing light regimes (‘physiological plasticity’). Concluding, we suggest that the physiological adaptation to light is the main factor driving the succession of the phytoplankton community during the first phases of the bloom (until the onset of thermal stratification) in the western Mediterranean Sea.

The combined effects of seasonal community succession and adaptive algal physiology on lipid profiles of coastal phytoplankton in the western English channel

Lipids are key constituents of marine phytoplankton, and some fatty acids (key constituents of lipids) are essential dietary components for secondary producers. However, in natural marine ecosystems the interactions of factors affecting seasonal phytoplankton lipid composition are still poorly understood. The aim of this study was to assess the roles of seasonal succession in phytoplankton community composition and nutrient concentrations, on the lipid composition of the phytoplankton community. Fatty acid and polar lipid composition in seston was measured in surface waters at the time series station L4, an inshore station in the Western English Channel, from January to December 2013. Redundancy analyses (RDA) were used to identify factors (abiotic and biotic) that explained the seasonal variability in phytoplankton lipids. RDA demonstrated that nutrients (namely nitrogen) explained the majority of variation in phytoplankton lipid composition, as well as a smaller explanatory contribution from changes in phytoplankton community composition. The physiological adaptations of the phytoplankton community to nutrient deplete conditions during the summer season when the water column was stratified, was further supported by changes in the polar lipid to phytoplankton biomass ratios (also modelled with RDA) and increases in the lipid to chlorophyll a ratios, which are both indicative of nutrient stress. However, the association of key fatty acid markers with phytoplankton groups e.g. 22:6 n-3 and dinoflagellate biomass (predominant in summer), meant there were no clear seasonal differences in the overall degree of fatty acid saturation, as might have been expected from typical nutrient stress on phytoplankton. Based on the use of polyunsaturated fatty acids (PUFA) as markers of ‘food quality’ for grazers, our results suggest that in this environment high food quality is maintained throughout summer, due to seasonal succession towards flagellated phytoplankton species able to maintain PUFA synthesis under surface layer nutrient depletion.

Co-inheritance of two rare genodermatoses (Papillon Lefevre syndrome and Oculocutaneous Albinism Type 1) in two families

The co-occurrence of two rare recessive genetic conditions in apparently unrelated individuals or families is extremely rare. Two geographically distant and apparently unrelated families were identified in which individuals were simultaneously affected by two rare recessive mendelian syndromes, Papillon-Lefevre syndrome and type 1 oculocutaneous albinism. The families were tested for mutations in the causative genes, cathepsin C (CTSC) and tyrosinase (TYR), respectively, by direct sequencing. To assess the relationship of the two families, both families were tested for polymorphisms at eight microsatellite markers spanning both CTSC and TYR loci. Independent mutations (c.318-1G-->A and c.817G-->C/p.W272C) were identified in CTSC and TYR, respectively, that were shared by the affected individuals in both families. The two affected genes lie close together on chromosome bands 11q14.2-14.3, and studies with linked genetic markers suggested that the families shared a small chromosomal segment carrying both mutations that had been transmitted intact from a remote common ancestor. The co-occurrence of the two rare diseases in multiple families depends on their shared chromosomal location, but not on any shared pathogenic mechanism.

‘Doing it with men’: feminist research practice and patriarchal inheritance practices in Welsh family farming

Internationally, the gender relations of the family farming ‘way of life’ have beenshown to be stubbornly persistent in their adherence to patriarchal inheritancepractices. This article demonstrates how such ‘agri-cultural’ practices are situated bothwithin the subjective sphere of farming individuals’ and within global agri-economics,bringing new challenges to patrilineal farm survival. It is suggested here that the recenttendency for post-structuralist theorisation in rural studies has underestimated theexistence and impact of patrilineal patterns in family farming. Such patterns mean thatwomen are shown to largely occupy relational gender identities as the ‘helper’, whilstmen are strongly identified as the ‘farmer’. Drawing on repeated life-history interviewsconducted with farming men and women from Powys, Mid Wales, the aim of thisarticle is to generate debate as to the extent to which men can be brought into feministresearch practice in order to reveal patriarchy to a greater degree. The article begins bysituating the near-exclusion of men from feminist research practice within theoreticaldevelopments in feminist geography. This discussion also assists in deriving issues ofresearch methods, positionality and interpretive power which focus the integration ofempirical material in the methodological reflections provided in section three. In sectiontwo, the rationale for the epistemological stance taken in the research is provided. Thearticle provides an example of the successful integration of men into a feminist researchframe, suggests avenues for theoretical development and identifies future researchdirections which can be informed by ‘doing it with men’.

Keywords: epistemology; family farming; feminist res

The European oyster (Ostrea edulis) and its epibiotic succession

This study aimed to investigate intra- and inter-site differences in the epibiota on the European oyster Ostrea edulis of different ages and on hard substrata to assess their contribution to biodiversity. This research has shown that shells of O. edulis do show higher species diversity than non-living hard substrata and as oysters grow larger epibiotic diversity will increase. This investigation has revealed that O. edulis possesses biogenic engineering qualities and the value of O. edulis as a vehicle for increasing biodiversity should not be underestimated. Relatively few studies have examined the shell surfaces of Ostrea edulis, which, together with their associated epifauna provide a large portion of the natural hard substrata for sessile filter-feeding organisms, including oysters, in coastal and estuarine ecosystems. It can be considered a keystone species which has an influence on intertidal and subtidal community structures.

Family Histories and Rural Inheritance in Kenya

Inheritance systems and practices have a key role in people’s ability to exit poverty, or, conversely, plunging them further into it. As land is the major asset in low-income developing countries, how property is passed on and divided between future generations is a significant factor. This paper looks at inheritance through minimally-structured interviews with several generations of Kenyan families, seeking to explain that the how and why of poverty can be understood in the wider family context. It analyses their fortunes and misfortunes over a given time period in the context of property ownership rights. It also looks at the impact of education and the inheritance of cultural capital. When both fertility and survival are high, traditional patterns of land inheritance can lead to progression sub-division of land with long-term adverse implications for sustainability. While inheritance in Kenya is male dominated, the paper nonetheless examines the position of women in the chain as vectors of male property rights. The application of male-oriented customary law where inheritance is concerned, rather than the use of statutory legislation, was found to be the reality for the overwhelming majority of the participants in the study.