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Harmful Algal Blooms (HAB) are complex to manage due to their intermittent nature and their severe impact on the economy and human health. The conditions which promote HAB have not yet been fully explained, though climate change and anthropogenic intervention are pointed as significant factors. The rise of water temperature, the opening of new sea canals and the introduction of ship ballast waters all contribute to the dispersion and establishment of toxin-producing invasive species that promote the settling of emergent toxins in the food-chain. Tetrodotoxin, ciguatoxin, palytoxin and cyclic imines are commonly reported in warm waters but have also caused poisoning incidents in temperate zones. There is evidence that monitoring for these toxins exclusively in bivalves is simplistic and underestimates the risk to public health, since new vectors have been reported for these toxins and as well for regulated toxins such as PSTs and DSTs. In order to avoid public health impacts, there is a need for adequate monitoring programs, a need for establishing appropriate legislation, and a need for optimizing effective methods of analysis. In this review, we will compile evidence concerning emergent marine toxins and provide data that may indicate the need to restructure the current monitoring programs of HAB.

Life Cycle Assessment (the systematic analysis of the environmental impact of products during their entire life cycle), Carbon Footprint and Water Footprint assessments play an important role in decision-making processes. These assessments can help guide land management decisions and will likely play a larger role in the future, especially in natural areas with high biodiversity. Agriculture is a substantial consumer of fresh water, so it is important to identify causes and possible solutions to optimize agricultural water use. Water footprint assessments consider water consumption from several points of view and aid in reaching Sustainable Development Goals. Olive trees are a widespread agricultural crop growing in the Mediterranean Basin and are particularly important in the Umbria region in Italy. This paper estimates the water footprint impact related to the production of 1 kg of olives in a rainfed olive orchard managed using low environmental impact techniques. Eleven years of data collection (meteorological data, olives yield data, processes data) are analyzed for typical rural conditions. The results show that local management techniques have lower water requirements than standard international usages. These results can be used to improve and to further explore agricultural water use.

Impact of drought under enriched CO2 atmosphere on ecophysiological and leaf metabolic response of the sub-mediterranean Q. pyrenaica oak was studied. Seedlings growing in climate chamber were submitted to moderate drought (WS) and well-watered (WW) under ambient ([CO2]amb =400 ppm) or CO2 enriched atmosphere ([CO2]enr =800 ppm). The moderate drought endured by seedlings brought about a decrease in leaf gas exchange. However, net photosynthesis (Anet) was highly stimulated for plants at [CO2]enr. There was a decrease of the stomatal conductance to water vapour (gwv) in response to drought, and a subtle trend to be lower under [CO2]enr. The consequence of these changes was an important increase in the intrinsic leaf water use efficiency (WUEi). The electron transport rate (ETR) was almost a 20 percent higher in plants at [CO2]enr regardless drought endured by seedlings. The ETR/Anet was lower under [CO2]enr, pointing to a high capacity to maintain sinks for the uptake of extra carbon in the atmosphere. Impact of drought on the leaf metabolome, as a whole, was more evident than that from [CO2] enrichment of the atmosphere. Changes in pool of non-structural carbohydrates were observed mainly as a consequence of water deficit including increases of fructose, glucose, and proto-quercitol. Most of the metabolites affected by drought back up to levels of non-stressed seedlings after rewetting (recovery phase). It can be concluded that carbon uptake was stimulated by [CO2]enr, even under the stomatal closure that accompanied moderate drought. In the last, there was a positive effect in intrinsic water use efficiency (WUEi), which was much more improved under [CO2]enr. Leaf metabolome was little responsible and some few metabolites changed mainly in response to drought, with little differences between [CO2] growth conditions.

ABSTRACTThe aquifer system of Doñana (SW Spain) represents the most important freshwater source in the Doñana Natural Area. Its spatiotemporal dynamics favours the hydrological connection between surface and subsurface ecosystems, and promotes matter fluxes among the different terrestrial and aquatic systems present here. This aquifer has been intensively studied from a hydrogeological point of view but little is known from an ecological perspective. In order to understand the ecological roles played by microbial communities in this system, we conducted a long‐term seasonal study of bacterial abundance, cell biomass, bacterial biomass and functional activities over a 2‐year period. Bacterial abundance ranged between 2.11 ± 1.79 × 105 and 8.58 ± 6.99 × 107 bacteria mL−1 groundwater, average cell biomass was estimated to be 77.01 ± 31.56 fgC and bacterial biomass varied between 8.99 ± 4.10 × 10−2 and 5.65 ± 0.70 µgC mL−1. Iron‐related bacteria showed the highest activities among the functional groups studied. Moreover, among the variables that usually control spatial distributions of microbial communities in aquifer systems, depth did not have a relevant effect on this aquifer, at least in the range of depths studied, but grain size, probably due to its direct effects on hydrogeological parameters, such as permeability or porosity, appeared to exert moderate control, principally in terms of bacterial abundance. Finally, significant seasonal differences in the means of these microbiological variables were also observed; temperature seems to be the main factor controlling the temporal distribution of microbial communities in this aquifer system.

The land transformation process in the last decades produced the urbanization growth in flat and coastal areas all over the world. The combination of natural phenomena and human pressure is likely one of the main factors that enhance coastal dynamics. These factors lead to an increase in coastal risk (considered as the product of hazard, exposure, and vulnerability) also in view of future climate change scenarios. Although each of these factors has been intensively studied separately, a comprehensive analysis of the mutual relationship of these elements is an open task. Therefore, this work aims to assess the possible mutual interaction of land transformation and coastal management zones, studying the possible impact on local coastal communities. The idea is to merge the techniques coming from urban planning with data and methodology coming from the coastal engineering within the frame of a holistic approach. The main idea is to relate urban and land changes to coastal management. Then, the study aims to identify if stakeholders’ pressure motivated the deployment of rigid structures instead of shoreline variations related to energetic and sedimentary balances. The influence of coastal protection (described by an indicator taking into account the linear density of the rigid protection extension alongshore) measures have been considered. Finally, the economical performances in the period just after the land transformation have been studied by means of a dimensionless index based on the concept of the local unit. The method has been applied to the case study of the Abruzzo Region. Results reveal a large urbanization growth and a generalized over-protection of the coast with a resulting spatial alternation of shoreline retreat and advance. On the other hand, the analysis of the local economy reveals that the presence of tourism activities does not necessarily lead to an increase in the local economy. Indeed, the most important improvement in local economies in the region can be associated with coastal stretches characterized by a high environmental value.

Efforts are needed in order to increase confidence for carbon accounts in the land use sector, especially in tropical forest ecosystems that often need to turn to default values given the lack of precise and reliable site specific data to quantify their carbon sequestration and storage capacity. The aim of this study was then to estimate biomass and carbon accumulation in young secondary forests, from 4 and up to 20 years of age, as well as its distribution among the different pools (tree including roots, herbaceous understory, dead wood, litter and soil), in humid tropical forests of Costa Rica. Carbon fraction for the different pools and tree components (stem, branches, leaves and roots) was estimated and varies between 37.3% (±3.3) and 50.3% (±2.9). Average carbon content in the soil was 4.1% (±2.1). Average forest plant biomass was 82.2 (±47.9) Mg ha−1 and the mean annual increment for carbon in the biomass was 4.2 Mg ha−1 yr−1. Approximately 65.2% of total biomass was found in the aboveground tree components, while 14.2% was found in structural roots and the rest in the herbaceous vegetation and necromass. Carbon in the soil increased by 1.1 Mg ha−1 yr−1. Total stored carbon in the forest was 180.4 Mg ha−1 at the age of 20 years. In these forests, most of the carbon (51&-83%) was stored in the soil. Models selected to estimate biomass and carbon in trees as predicted by basal area had R2 adjustments above 95%. Results from this study were then compared with those obtained for a variety of secondary and primary forests in different Latin-American tropical ecosystems and in tree plantations in the same study area. Universidad Nacional de Costa Rica Ministerio de Ciencia y Tecnología, Costa Rica

Continuous phosphorus discharges in bodies of water, generated by human activities, such as agriculture, domestic effluences or wastewater from industrial processes, produce contaminated water and eutrophication. For this reason, efficient and low-cost systems that can remove phosphorus from contaminated water are necessary. In addition, it is important to generate renewable energy such as the energy produced in biomass power plants, taking advantage of the available biomass waste in each place. When producing this renewable energy, the resulting ash is a residue that can be used for phosphorus removal by adsorption processes. Moreover, according to the concept of the circular economy, the ash waste generated in this bio energy process should be reduced as much as possible. One of the advantages of this research being that surplus phosphorus-laden ash can be reused as fertilizer in agricultural fields. Considering this, the efficiency of reed ash (RA) (Phragmites australis) has been analysed in batch experiments, as well as the effect of several parameters on the removal of phosphate, such as contact time, phosphate-ash ratio, ash dose and temperature. Significant results obtained show that RA can be used to improve water quality.