Josefina Garrido

Evolution of microbial dynamics during the maturation phase of the composting of different types of waste

During composting, facilities usually exert greater control over the bio-oxidative phase of the process, which uses a specific technology and generally has a fixed duration. After this phase, the material is deposited to mature, with less monitoring during the maturation phase. While there has been considerable study of biological parameters during the thermophilic phase, there is less research on the stabilization and maturation phase. This study evaluates the effects of the type of starting material on the evolution of microbial dynamics during the maturation phase of composting. Three waste types were used: sludge from the fish processing industry, municipal sewage sludge and pig manure, each independently mixed with shredded pine wood as bulking agent. The composting system for each waste type comprised a static reactor with capacity of 600L for the bio-oxidative phase followed by stabilization and maturation phase in triplicate 200L boxes for 112days. Phospholipid fatty acids, enzyme activities and physico-chemical parameters were measured throughout the maturation phase. The evolution of the total microbial biomass, Gram + bacteria, Gram - bacteria, fungi and enzymatic activities (β-glucosidase, cellulase, protease, acid and alkaline phosphatase) depended significantly on the waste type (p<0.001). The predominant microbial community for each waste type remained present throughout the maturation process, indicating that the waste type determines the microorganisms that are able to develop at this stage. While fungi predominated during fish sludge maturation, manure and municipal sludge were characterized by a greater proportion of bacteria. Both the structure of the microbial community and enzymatic activities provided important information for monitoring the composting process. More attention should be paid to the maturation phase in order to optimize composting.

A biogeochemical approach to understanding the accumulation patterns of trace elements in three species of dragonfly larvae: evaluation as biomonitors.

The accumulation patterns of different trace elements (As, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn) were studied in three species of dragonfly larvae (Cordulegaster boltoni, Boyeria irene and Onychogomphus uncatus). Additionally these species were assessed as potential biomonitors in a lotic ecosystem (Louro River, Spain). Element concentrations were determined by inductively coupled plasma optical emission spectrometry (ICP-OES) in both dragonfly larvae and river sediments. The surface of the larvae was observed and analyzed with scanning electron microscopy (SEM). A desorption test was used to establish the percentage of element adsorbed into the exoskeleton. Field biomonitoring studies were made considering the first part of the river as a control area in relation to the second part, which was severely polluted by industrial and domestic activities. Upon application of principal component analysis (PCA), two different element groups were found in relation to element bioaccumulation. Cu, Cd and Zn were mainly associated with the inner part of the larvae. As, Cr, Fe, Mn, Ni and Zn were found on the outer body parts, related with deposition of oxyhydroxides in the hydrocycle. SEM revealed a layer of inorganic particles, similar in composition to fine bed sediments. Significant relations between the element content of this group and that of sediments at the sampling site were found. Differences in bioaccumulation for each of the three species, except for As, were observed. Dragonfly larvae revealed their ability to reflect environmental concentrations of As in freshwater media.

Effects of non-native Spartina patens on plant and sediment organic matter carbon incorporation into the local invertebrate community

The cycling of organic matter through food webs is a fundamental process that may be altered by the invasion of non-indigenous plants. We explored consequences of the invasion of non-indigenous Spartina patens to the composition of soil organic matter (SOM) and to detritivore and herbivore diets in the upper salt marsh within Corrubedo National Park, northwest Spain. We tested for the incorporation of S. patens carbon (C) into SOM and by detritivores and herbivores using stable isotope analysis, focusing primarily on detritivorous enchytraeid oligochaetes and herbivorous insects. Stable isotope results indicated that C derived from S. patens has been incorporated into SOM. Elevated densities of enchytraeids in stands of S. patens, and their incorporation of C derived from this plant, suggested that dense patches of S. patens may facilitate detritivore populations. In contrast, although insect herbivores used S. patens as habitat, there was little isotopic evidence for the widespread incorporation of S. patens-derived C by these consumers. The population and dietary response of enchytraeids to S. patens suggests that S. patens invasion could indirectly influence soil processes and pathways mediated by detritivore activity (e.g., soil respiration rates, nutrient retention and transformation, energy flow). The loss of food resources to insect herbivores alters local food webs. However, insect herbivores may move and feed on native plants elsewhere. As a result, insect populations may be less immediately impacted than soil detritivore populations by S. patens. Our study suggests that the influences of S. patens invasion extend beyond the more obvious changes in native plant abundance, to include differing responses in the cycling of organic matter between detritivore and insect herbivore food web pathways.

Altitudinal Distribution of Aquatic Beetles (Coleoptera) in Northern Tunisia: Relationship between Species Richness and Altitude

ABSTRACT An ecological study of the geographical distribution of aquatic Adephaga and Polyphaga (Coleoptera) in the mountains of northern Tunisia was carried out with an analysis of the effect of altitude on the distribution of 123 species collected from 64 sampling sites. Species richness was analyzed at different altitudinal levels and the indicator species were determined by establishing their altitude profile in terms of reciprocal species-factor information. Species richness decreases with increasing altitude. Thirty representative species are placed into three groups: species present along the entire altitudinal gradient; species present at high altitude; and species occurring at low altitude.

Morphological reply to a DNA call: a new cryptic species of Hydraena from western Europe, with a complete overview of the Hydraena gracilis complex (Coleoptera: Hydraenidae: “Haenydra” lineage)

Recent molecular analyses revealed unexpected genetic variability within Hydraena gracilis, one of the most common and widespread European moss beetles, belonging to the West Palaearctic endemic “Haenydra” lineage. For this taxon, molecular data univocally evidenced two distinct clades, the first one including populations from the Iberian Peninsula, and the second including populations from central and eastern Europe. Aedeagal morphology of H. gracilis was further investigated, finally demonstrating the actual existence of a new cryptic species of the H. gracilis complex in Portugal, Spain and the French Pyrenees. The geographical range of the true H. gracilis was consequently revised. Finally, dichotomous keys for males of all species belonging to the H. gracilis complex, and for males of all the Iberian “Haenydra” species, are also supplied.

Biodiversity and Conservation of Coastal Lagoons

Wetlands are sites of high biodiversity and productivity (Mitsch & Gosselink, 2000). They provide essential services, such as maintenance of atmosphere composition, key habitats for migratory species, and important nursery areas (Basset & Abbiati, 2004), but these ecosystems have suffered a serious decline worldwide due to human influence (Shine & Klemm, 1999; Solimini et al., 2008; Stenert & Maltchik, 2007). Declining water quality, drainage, eutrophication and catchment disturbances such as development, loss of natural vegetation and poor agricultural practices are changing the fundamental ecology of shallow lakes in much of the world (Drake et al., 2011). Different management strategies have been developed to solve these conservation problems, for instance the Europeans Natura 2000 network and Water Framework Directive (WFD). Among these aquatic systems, coastal wetlands have been subject to massive environmental degradation and habitat destruction worldwide (Goudie, 1990). For example, more than 50% of the original area of coastal wetlands that existed in 1900 has been lost in most countries of Western Europe (Jones & Hughes, 1993). However, not until very recently have they become the focus of conservation interest per se (Abbiati & Basset, 2001; Barnes, 1999) with the declaration of Special Areas of Conservation as a consequence of their listing as a priority habitat type (1150*) on Annex I of the European Union Habitats Directive (Council Directive 92/43/EEC). Coastal lagoons constitute a common coastal environment, occupying 13% of coastal areas worldwide (Kjerfve, 1994). The conservation of these habitats depends largely on the assessment of their natural characteristics, especially biodiversity, which is one of the main criteria used when elaborating wetland protection policies (Ramsar Convention Bureau, 2005). To assess the conservation status of wetlands correctly it is necessary to include studies of the invertebrate fauna. In this sense, the composition and abundance of benthic invertebrates is one of the most important criteria to be considered. Within this group of organisms are insects, especially Coleoptera and Hemiptera, which are two of the most common groups in these environments and also two of the most important groups in the freshwater food chain. The purpose of this chapter is to study the importance of the invertebrate fauna in the conservation of coastal lagoons and to assess the effectiveness of protecting areas on the conservation of their biological values. The questions are: “Is the Natura 2000 network

A study on the family Hydrophilidae Latreille, 1802 (Coleoptera) from Northern Tunisia

Abstract We review the distribution of the water scavenger beetles (Hydrophilidae) in the northern part of Tunisia, based on data from 54 sites collected over the course of a year. In total, 21 hydrophilid species were found. The most interesting ones from the zoogeographical point of view are: Enochrus nigritus Sharp, 1872, Enochrus affinis Thunberg, 1794, Laccobius revelierei Perris, 1864 (all newly recorded for Tunisia), and Laccobius orientalis Knisch, 1924 and Berosus spinosus Steven, 1808 (newly recorded for northern Africa). An updated checklist of hydrophilid species occurring in the northern Tunisia is provided. The composition of the hydrophilid fauna in the area is assessed using the indexes of richness, abundance and diversity. We discuss possible causes of this phenomenon; identify the most valuable water beetle habitats within the investigated area that should be protected by law.

The microhabitat preferences of Trichoptera in rivers in north-western Spain

We analysed the microhabitat preferences of caddisfly species in four rivers in north-western Spain. In each river, we sampled five sites with different types of substrate. These sites were characterised in situ according to the predominant material type (macrophytes, moss, pebbles and sand). A one-way ANOVA was used to test for significant differences in species abundance among substrates, and a nested ANOVA was used to test for significant differences in physical and chemical variables among rivers and sampling sites. A similarity percentage-species contribution analysis was performed to estimate the contribution of each species to the characterisation of each substrate. We observed significant differences in the abundance of seven species (Drusus bolivari, Glossosoma privatum, Larcasia partita, Micrasema longulum, M. servatum, M. gr. moestum and Sericostoma sp.) among substrates, confirming that these species have substrate preferences. According to similarity percentage-species contribution, the species that contributed most to differences were as follows: for sand, Sericostoma sp.; for macrophytes, Rhyacophila adjuncta, Hydropsyche ambigua, Sericostoma sp.; for moss, Micrasema gr. moestum, M. servatum, M. longulum, Hydropsyche tibialis and R. adjuncta; and for pebbles, Sericostoma sp., Larcasia partita and H. tibialis. These preferences can be explained by the fact that different species use different materials from the substrate to build their cases and also as a source of stability, protection and food.

Nymphal feeding habits of Perla madritensis Rambur 1842 (Plecoptera: Perlidae)

Summary The diet of Perla madritensis, endemic species of the northern half of the Iberian Peninsula, is described for the first time by means of a study carried out in north-western Spain. As other species of the genus Perla, this taxon behaves mainly as predator, with Chironomidae, followed by Baetidae, being the most abundant prey in its gut. Shifts in diet composition were detected in relation to size in this species, with smaller prey being replaced by larger ones such as Simuliidae and Leptophlebiidae when the nymphs become larger.

Abundance and diversity of the aquatic beetles in a Mediterranean stream system (Northern Tunisia)

Summary. The understanding of community structuring factors is a fundamental issue in community ecology. We investigate the biodiversity of the water beetle in the Ichkeul Lake stream system located in Northern Tunisia, with emphasis on the effect of several environmental variables on their assemblage structure. This area is of a great importance since it was included in the list of preserved waterbodies by RAMSAR convention on wetlands, MAB (Man And Biosphere), UNESCO (United Nations Educational, Scientific and Cultural Organization). Consequently, the study of its biodiversity constitutes a required way to better conduct this protection aim. Special attention must be paid to species endemic to North Africa, as all of them require conservation measures. Sampling was carried out over the course of a year. Dissolved oxygen, conductivity, pH, temperature and turbidity were measured for each study site. Water permanence, velocity, aquatic vegetation and substrate type were considered. The investigated streams showed a spatial heterogeneity in water depth, water velocity, turbidity, mineralization and substrate type, but homogeneity in temperature and dissolved oxygen. A total of 68 coleopteran species were identified from the investigated area, belonging to different chorotypes and phenological categories. The coleopteran assemblage was assessed in terms of four community parameters: abundance, richness (S), diversity (Shannon–Wiener index: H′), and evenness (Pielou index: J′). Species composition was analyzed by multivariate analysis. Sites were arranged into two groups based on their species affinity by non-parametric multidimensional scaling (MDS) ordination on the basis of Bray–Curtis similarity at a similarity of 50%. Principal component analysis (PCA) highlighted the species response to the environmental variables. It revealed the distribution profile of sampled species; on the first axis, F1, a maximum number of variables are projected. Its positive pole is defined by the majority of species, with tolerance of high salinity. On its negative pole only three species are present. Its positive pole is defined by lentic phytophagous species, showing a preference for well vegetated waters. Its negative pole is marked by the species L. orientalis, associated with the majority of water parameters.