The political ecology of Jatropha plantations for biodiesel in Tamil Nadu, India

Jatropha curcas is promoted internationally for its presumed agronomic viability in marginal lands, economic returns for small farmers, and lack of competition with food crops. However, empirical results from a study in southern India revealed that Jatropha cultivation, even on agricultural lands, is neither profitable, nor pro-poor. We use a political ecology framework to analyze both the discourse promoting Jatropha cultivation and its empirical consequences. We deconstruct the shaky premises of the dominant discourse of Jatropha as a “pro-poor” and “pro-wasteland” development crop, a discourse that paints a win-win picture between poverty alleviation, natural resource regeneration, and energy security goals. We then draw from field-work on Jatropha plantations in the state of Tamil Nadu to show how Jatropha cultivation favors resource-rich farmers, while possibly reinforcing existing processes of marginalization of small and marginal farmers.

Comparative study of algal communities in acid and alkaline waters from Tinto, Odiel and Piedras river basins (SW Spain)

The distribution patterns of benthic algal assemblages in the Tinto, Odiel and Piedras rivers were analyzed during the winter of 2005 in 18 sampling stations. The main objective was to assess and compare the algal communities and parameters affecting them both in the zones affected by acid mine drainage (AMD) and in naturally alkaline waters. A total of 108 benthic diatom taxa and 31 non-diatom taxa were identi ed. Results showed large differences between algal communities in the two environments: Pinnularia acoricola, P. subcapitata and Eunotia exigua were the most frequent diatom taxa in regions affected by acid mine drainage, along with algae like Klebsormidium and Euglena mutabilis were the most relevant non-diatom taxa. In alkaline waters the dominant diatom taxa were Planothidium frequentissimum, Gomphonema angustum, Fragilaria capucina, and some species of Navicula (N. viridula, N. veneta or N. radiosa), accompanied by Oscillatoria and Anabaena as well as by streptophytes of the group of zygnemataceae and desmidiaceae

Combining phospholipases and a liquid lipase for one-step biodiesel production using crude oils

Background Enzymatic biodiesel is becoming an increasingly popular topic in bioenergy literature because of its potential to overcome the problems posed by chemical processes. However, the high cost of the enzymatic process still remains the main drawback for its industrial application, mostly because of the high price of refined oils. Unfortunately, low cost substrates, such as crude soybean oil, often release a product that hardly accomplishes the final required biodiesel specifications and need an additional pretreatment for gums removal. In order to reduce costs and to make the enzymatic process more efficient, we developed an innovative system for enzymatic biodiesel production involving a combination of a lipase and two phospholipases. This allows performing the enzymatic degumming and transesterification in a single step, using crude soybean oil as feedstock, and converting part of the phospholipids into biodiesel. Since the two processes have never been studied together, an accurate analysis of the different reaction components and conditions was carried out. Results Crude soybean oil, used as low cost feedstock, is characterized by a high content of phospholipids (900 ppm of phosphorus). However, after the combined activity of different phospholipases and liquid lipase Callera Trans L, a complete transformation into fatty acid methyl esters (FAMEs >95%) and a good reduction of phosphorus (P <5 ppm) was achieved. The combination of enzymes allowed avoidance of the acid treatment required for gums removal, the consequent caustic neutralization, and the high temperature commonly used in degumming systems, making the overall process more eco-friendly and with higher yield. Once the conditions were established, the process was also tested with different vegetable oils with variable phosphorus contents. Conclusions Use of liquid lipase Callera Trans L in biodiesel production can provide numerous and sustainable benefits. Besides reducing the costs derived from enzyme immobilization, the lipase can be used in combination with other enzymes such as phospholipases for gums removal, thus allowing the use of much cheaper, non-refined oils. The possibility to perform degumming and transesterification in a single tank involves a great efficiency increase in the new era of enzymatic biodiesel production at industrial scale.

A comparative study of the intercellular connections between parasite/host in two Gelidiocolax/Gelidium algal parasitic systems

Comparative ultrastructural study of the intercellular connections between parasite and host cells in two algal parasitic systems, Gelidiocolax christianae Feldmann and Feldmann/Ge/iV/ium spathulatum (Kutz.) Bornet and Gelidiocolax deformans Seoane Camba/Gelidium sesquipedale (Clem.) Thur, shows quantitative and structural differences. The number of free conjunctor cells (before fusión with the adjacent host cells) differs between the two parasitic systems and is inversely related to the number of complex pit connections. The fibrillar cell wall structure of the conjunctor cells and the lamellar structure of the complex pit plugs in the two systems are also different A hypothesis concerning the different activity of the conjuntor cell wall in the two parasitic systems, related with the different structural appearance, is proposed.

Response of photosynthetic organisms to global change: an approach based on marker pigments

Report for the scientific sojourn carried out at the Department of Freshwater Ecology, National Environmetal Research Institute, Denmark, from 2006 to 2008. The main objective of the project was to reconstruct photosynthetic organism community composition using pigmentbased methods and to study their response to natural (e.g. climate) or anthropogenic (e.g. eutrophication) perturbations that took place in the system over time. We performed a study in different locations and at different temporal scales. We analysed the pigment composition in a short sediment record (46 cm sediment depth) of a volcanic lake (Lake Furnas) in the Azores Archipelago (Portugal). The lake has been affected during the last century by successive fish introductions. The specific objective was to reconstruct the lake’s trophic state history and to assess the role of land-use, climate and fish introductions in structuring the lake community. Results obtained suggested that whereas trophic cascade and changes in nutrient concentrations have some clear effects on algal and microbial assemblages, interpreting the effects of changes in climate are not straightforward. This is probably related with the rather constant precipitation in the Azores Islands during the studied period. We also analysed the pigment composition in a long sediment record (1800 cm sediment depth) of Lake Aborre (Denmark) covering ca. 8kyr of lake history. The specific objective was to describe changes in lake primary production and lake trophic state over the Holocene and to determine the photosynthetic organisms involved. Results suggested that external forcing (i.e. land use changes) was responsible of erosion and nutrient run off to the lake that contributed to the reported changes in lake primary production along most of the Holocene.

The effects of feeding Karlodinium veneficum (PLY # 103; Gymnodinium veneficum Ballantine) to the blue mussel Mytilus edulis

The effects of exposure to the type species for Karlodinium veneficum (PLY # 103) on immune function and histopathology in the blue mussel Mytilus edulis were investigated. Mussels from Whitsand Bay, Cornwall (UK) were exposed to K. veneficum (PLY # 103) for 3 and 6 days. Assays for immune function included total and differential cells counts, phagocytosis and release of extra cellular reactive oxygen species. Histology was carried out on digestive gland and mantle tissues. The toxin cell quota for K. veneficum (PLY #103) was measured by liquid chromatography-mass spectrometry detecting two separable toxins KvTx1 (11.6 ± 5.4 ng/ml) and KvTx2 (47.7 ± 4.2 ng/ml). There were significant effects of K. veneficum exposure with increasing phagocytosis and release of reactive oxygen species following 6 days exposure. There were no significant effects on total cell counts. However, differential cell counts did show significant effects after 3 days exposure to the toxic alga. All mussels produced faeces but not pseudofaeces indicating that algae were not rejected prior to ingestion. Digestive glands showed ingestion of the algae and hemocyte infiltration after 3 days of exposure, whereas mantle tissue did not show differences between treatments. As the effects of K. veneficum were not observed in the mantle tissue it can be hypothesized that the algal concentration was not high enough, or exposure long enough, to affect all the tissues. Despite being in culture for more than 50 years the original K. veneficum isolate obtained by Mary Parke still showed toxic effects on mussels.

Fabricació i anàlisi del biodièsel

La producció de biodièsel a partir d'olis de cuina utilitzats, amb l'objectiu de transformar un residu en un producte amb valor comercial i ambiental, és més net que els combustibles fòssils i contribueix a disminuir el gran consum de petroli que estem fent. En una primera part teòrica s’ha realitzat un treball de recerca d' informació del biodièsel per saber si és un bon combustible i si podria ser un possible substitut dels combustibles fòssils. En quant a la part pràctica l'objectiu principal ha estat fabricar el biodièsel . Les matèries primeres són oli de gira-sol i oli de cuina utilitzat, per tal de comparar les seves qualitats. S’ha arribat a la conclusió que presenten característiques molt semblants. Després de fer les anàlisis físico-químics de qualitat vam fer una mescla dels dos biodièsels fabricats, i el vam provar en un motor Dièsel per comprovar si funciona correctament i fer una comparació dels gasos emesos pel nostre combustible amb els emesos pel gasoil comercial. El resultat va ser molt positiu ja que el motor va funcionar correctament, i la comparació de gasos va sortir tal i com esperàvem ja que les quantitats de diòxid i monòxid de carboni emeses eren menors que en el gasoil.

Elaboració de nous recursos docents en el camp de la biologia vegetal, mitjançant l'ús de noves tecnologies de microscòpia com làser confocal i multifotó

Aquest projecte s'ha realitzat al Servei de Microscòpia de la Universitat Autònoma de Barcelona, i ha tingut una durada de dos anys (2007-2009). Els objectius concrets d'aquest projecte assolits per a les diferents assignatures ha estat l'anàlisi de característiques citològiques, característiques morfològiques i anatòmiques de les estructures vegetatives dels diferents nivells d’organització, característiques morfològiques i anatòmiques de les estructures reproductores. El material docent obtingut en aquest projecte està sent utilitzat en les assignatures següents: Botànica Farmacèutica, Biodiversitat vegetal marina, Recursos vegetals aquàtics: les algues, Plantes d'ús alimentari, Conserv. i gestió de poblacions i comunitats marines, Usos i cultius de recursos algals marins, B. i diversitat de criptògames, Biologia II, Tècniques Exp. de biologia II, Botànica, Biologia animal i vegetal. Per a la realització de l’estudi, s'ha obtingut una col·lecció d’imatges al MLC, MER i MET per aclarir els criteris sistemàtics. Durant el primer any s’han adquirit totes les imatges necessàries, per tal de poder elaborar el material didàctic en suport digital. Durant el segon any s’ha implementat aquest material a les respectives classes pràctiques i s’ha avaluat la seva importància en la millora de la formació dels alumnes i del suport al professor. L’aplicació del material elaborat a la docència pràctica durant el tot segon any ha permès fer un primer estudi per valorar la seva eficàcia i fer-hi les correccions oportunes. Durant tot el projecte, el treball conjunt de professors i tècnics ha estat bàsic per a l’obtenció de material didàctic adequat a la realitat dels estudis actuals i a la docència pràctica.

Estudi de la problemàtica de terbolesa de l’estany del Cortalet

S’ha detectat un problema de terbolesa de les aigües de l’estany del Cortalet del PNAE. El sòl d’aquest estany és de tipus sòdic, si pateix alguna alteració és possible que es presenti una desmembració deguda a l’acció dispersant del sodi. Alguns estudis demostren que la vegetació actua com a agent estructurador d’aquest sòl i li dóna estabilitat al sediment. Segons això, podria ser que l’origen de la terbolesa de l’aigua fos causa d’aquesta acció dispersant del sodi en sòls mancats de vegetació. Per analitzar si aquesta és la causa de la terbolesa, s’ha dut a terme un assaig experimental in situ de les causes físiques de la terbolesa de l’aigua, on s’ha tractat d’aïllar una zona amb vegetació, d’una sense vegetació. Els resultats demostren que la terbolesa era major a les zones vegetades i descarten la hipòtesi de l’acció dispersant del sodi en el sediment en sòls mancats de vegetació. Els resultats en canvi suggereixen que les causes de la terbolesa podrien ser d’origen biològic. Atès que es troben diferències entre la producció primària planctònica generada pel fitoplàncton, i bentònica, generada per la biomassa algal

Resposta de les espècies algals a canvis en la disponibilitat de nutrients

L'objectiu general del projecte de tesi és el d'estudiar la resposta de les espècies algals a canvis en la disponibilitat de nutrients (i.e. NH4+/NO3-/PO43-). La hipòtesi de partida és que les alteracions en les concentracions absolutes i relatives de nutrients provoquen canvis en l'activitat de les espècies algals que seran més o menys intensos en funció de l’espècie i que són fruit de les característiques eco-evolutives intrínseques de cadascuna. Els objectius concrets es diferencien per l’escala temporal a la que s’observa la resposta, que va des de minuts fins a setmanes: Objectiu 1. Analitzar canvis a curt termini en l’activitat de les espècies degut a augments puntuals en la concentració absoluta i relativa de nutrients (NH4+/NO3-/ PO43-). S'ha vist que algunes espècies redueixen l’activitat fotosintètica a curt termini per destinar tots els recursos a l’assimilació de nutrients (Elrifi i Turpin 1986). S’estudiarà si aquesta pauta es troba de forma generalitzada i si respon a patrons evolutius, funcionals (mida, forma...) o ecològics (disponibilitat de nutrients). Objectiu 2. Analitzar, a mig termini, l’activitat de les espècies algals a diferents concentracions de NH4+/NO3-/ PO43-. Les respostes s’intentaran modelar, de manera que els paràmetres es puguin considerar trets funcionals característics de les espècies. S'estudiarà si la variabilitat en aquests trets respon a patrons evolutius o a d’altres trets funcionals com per exemple la mida. Objectiu 3. Analitzar com afecta, a llarg termini, la disponibilitat de nutrients en la composició d’espècies. Es detectarà quines espècies són més sensibles a les condicions de NH4+:NO3- i N:P del medi, i com es relaciona això amb les respostes específiques trobades en els objectius anteriors.

Biodièsel: impacte en origen del biodièsel consumit a Catalunya i a Espanya

Actualment la situació del mercat espanyol i català del biodièsel es caracteritza per les grans importacions d’oli de palma africana. Per a produir aquesta matèria primera s’estan establint plantacions a gran escala d’Elaeis guineensis (palma africana) a Indonèsia. El monocultiu d’Elaeis guineensis i la producció de l’oli tenen associats grans impactes ambientals i socials. Per una banda, els impactes ambientals són principalment la desforestació, el canvi d’ús del sòl, la pèrdua de biodiversitat, l’erosió del sòl i la contaminació de l’aire, del sòl de l’aigua. Per altra banda, els impactes socials més destacats són la violació dels drets humans dels pobles indígenes, els conflictes d’adquisició de terres i que es compromet la seguretat alimentària del país. Per tant, l’ús del biodièsel produït amb oli de palma africana redueix les emissions de GEH a Espanya i a Catalunya provocant un gran impacte ambiental i social a Indonèsia.

An integrated approach for the assessment of HAB dynamics in two NW Mediterranean bays from a GEOHAB perspective

Alfacs and Fangar Bay in the Ebro Delta, NW Mediterranean are the major sites in Catalonia for shellfish cultivation. These bays are subject to occasional closures in shellfish harvesting due to the presence of phycotoxins. Fish kills have also been associated with harmful algal blooms. The comparison of phytoplankton dynamics in both bays offers the opportunity to reveal differences in bloom patterns of species known to be harmful for the ecosystem and aquaculture activities. Field research is underway under the GEOHAB framework within the Core Research Project on HABs in Fjords and Coastal Embayments. The overall objective of this study is to improve our understanding of HAB biogeographical patterns, and key elements driving bloom dynamics in time and space within these semi-constrained embayments. Via the comparative approach we aim to improve the prediction for monitoring purposes, with a focus on Karlodinium spp. associated with massive kills of aquaculture species. This objective is addressed by incorporating long-term time series of phytoplankton identification and enumeration with the first results of recent field work in both bays. The latter includes the application of optical sensors, to yield a complementary view with enhanced spatial and temporal resolution of bloom phenomena.

Raw sewage harbors diverse viral populations

At this time, about 3,000 different viruses are recognized, but metagenomic studies suggest that these viruses are a small fraction of the viruses that exist in nature. We have explored viral diversity by deep sequencing nucleic acids obtained from virion populations enriched from raw sewage. We identified 234 known viruses, including 17 that infect humans. Plant, insect, and algal viruses as well as bacteriophages were also present. These viruses represented 26 taxonomic families and included viruses with single-stranded DNA (ssDNA), double-stranded DNA (dsDNA), positive-sense ssRNA [ssRNA(¿)], and dsRNA genomes. Novel viruses that could be placed in specific taxa represented 51 different families, making untreated wastewater the most diverse viral metagenome (genetic material recovered directly from environmental samples) examined thus far. However, the vast majority of sequence reads bore little or no sequence relation to known viruses and thus could not be placed into specific taxa. These results show that the vast majority of the viruses on Earth have not yet been characterized. Untreated wastewater provides a rich matrix for identifying novel viruses and for studying virus diversity.

The structure of Mediterranean rocky reef ecosystems across environmental and human gradients, and conservation implications

Historical exploitation of the Mediterranean Sea and the absence of rigorous baselines makes it difficult to evaluate the current health of the marine ecosystems and the efficacy of conservation actions at the ecosystem level. Here we establish the first current baseline and gradient of ecosystem structure of nearshore rocky reefs at the Mediterranean scale. We conducted underwater surveys in 14 marine protected areas and 18 open access sites across the Mediterranean, and across a 31-fold range of fish biomass (from 3.8 to 118 g m22). Our data showed remarkable variation in the structure of rocky reef ecosystems. Multivariate analysis showed three alternative community states: (1) large fish biomass and reefs dominated by non-canopy algae, (2) lower fish biomass but abundant native algal canopies and suspension feeders, and (3) low fish biomass and extensive barrens, with areas covered by turf algae. Our results suggest that the healthiest shallow rocky reef ecosystems in the Mediterranean have both large fish and algal biomass. Protection level and primary production were the only variables significantly correlated to community biomass structure. Fish biomass was significantly larger in well-enforced no-take marine reserves, but there were no significant differences between multi-use marine protected areas (which allow some fishing) and open access areas at the regional scale. The gradients reported here represent a trajectory of degradation that can be used to assess the health of any similar habitat in the Mediterranean, and to evaluate the efficacy of marine protected areas.

The population dynamics of Halecium petrosum and Halecium pusillum (Hydrozoa, Cnidaria), epiphytes of Halimeda tuna in the nortwestern Mediterranean

Halecium petrosum and Halecium pusillum on the alga Halimeda tuna from Tossa de Mar, northeastern Spain, were studied. Asexual reproduction of H. petrosum, by stolonisation, occurred throughout the year except for July and August. Asexual reproduction of H. pusillum, by planktonic propagules, occurred throughout the year. Sexual reproduction was limited to the autumn in H. petrosum and spring in H. pusillum. The growth rates of colonies of both species were rapid but declined with increased size. Mean colony size over two consecutive two week periods increased approximately five-fold and three-fold for H. petrosum, and six-fold and four-fold for H. pusillum. Mortality was estimated to be high for both species, especially in summer. The maximum life span of colonies (ramets) of both species was estimated to be only eight weeks. Consequently most colonies do not reproduce sexually. The absence of reproduction of H. petrosum in summer, when the turnover of algal thalli was greatest, probably contributed to the summer decline in its abundance. In both species the genet (clone) survives for unknown, possibly very long, periods by asexual reproduction which facilites colonisation of other substrata.