Legal measures to prevent and manage soil contamination and to increase food safety for consumer health: The case of Spain.

This article contains a brief overview of the European and Spanish environmental law framework for the prevention of soil contamination, for the management of contaminated soils and for consumers health protection in relation to agricultural crops. Some important aspects of the legislative framework for the prevention and management of soil contamination include recognising the possible risk to both human health and ecosystems that certain agricultural and industrial activities pose given the use of organic and inorganic chemical substances of a hazardous nature and pathogenic microorganisms. It is worth highlighting the milestone that many national constitutions include about the right to the environment. This right entails the obligation to protect it and to, therefore, protect soil from any degradation, including contamination. Legislation that protects soil from contamination and, consequently human health and ecosystems, is related mainly to agricultural activities (use of sewage sludge on farmlands, use of wastewater for irrigation, use of organic fertilisers and pesticides), and to industrial and commercial soil-contaminating activities. Consumer protection may be achieved through a legal system of environmental liability, specific measures to prevent contaminants entering soil, managing contaminated soils and a food traceability system. It is crucial to make the penalties for soil contamination offenses, and for violators of protective prohibitions, effective, proportionate and dissuasive. Global standards and guidelines on soil contamination could provide national legislative systems with substantive and procedural legal mechanisms to help prevent and manage soil contamination.

Managing low productive forests at catchment scale: Considering water, biomass and fire risk to achieve economic feasibility.

Semi-arid forests are water limited environments considered as low-productive. As a result, these forests usually end up unmanaged and abandoned, with the subsequent wild fire risk increasing, water yield decreasing and a general diminishing of the forest resilience. Hydrological-oriented silviculture could be a useful alternative that increases management possibilities by combining forest productivity and water yield. However, the slight water yield increase after forest management together with the low forest productivity, could make this option insufficient for semi-arid forests, and other goods and services should be included and quantified. In this sense, the present study analyzes to what extent semi-arid forest management for water yield results effective and profitable at catchment scale, and how does it improve when it is combined with other benefits such as biomass production and fire risk diminishing. To that end, the effects of forest management of semi-arid Aleppo pine post-fire regeneration stands are analyzed in terms of water yield (TETIS-VEG model), fire risk (KDBY index and FARSITE) and biomass production, at catchment scale. Regarding to water yield, the results confirmed the slight effect of forest management on its increase (average increase of 0.27 ±â€¯0.29 mm yr-1), at the same time that highlighted the role of the upper catchment area as an important water contributor. The management produced 4161.6 Mg of biomass, and decreased in 27±17% and 25.6 ±â€¯14.1% the fire risk and fire propagation, respectively. Finally, a simple economic estimation of the management profitability is carried out by means of comparing the Benefit/Cost ratio of the managed and unmanaged scenarios. Both scenarios were always above the unity when just considering water as benefit, although the unmanaged scenario produced a higher ratio, as no management costs are expended. Contrarily, when wildfire was also included into the evaluation, the situation is overturned for wildfires equal or higher than 1.5 day duration, where the forest management is shown as the most convenient alternative.

Hydrology-oriented forest management trade-offs. A modeling framework coupling field data, simulation results and Bayesian Networks.

Hydrology-oriented forest management sets water as key factor of the forest management for adaptation due to water is the most limiting factor in the Mediterranean forest ecosystems. The aim of this study was to apply Bayesian Network modeling to assess potential indirect effects and trade-offs when hydrology-oriented forest management is applied to a real Mediterranean forest ecosystem. Water, carbon and nitrogen cycles, and forest fire risk were included in the modeling framework. Field data from experimental plots were employed to calibrate and validate the mechanistic Biome-BGCMuSo model that simulates the storage and flux of water, carbon, and nitrogen between the ecosystem and the atmosphere. Many other 50-year long scenarios with different conditions to the ones measured in the field experiment were simulated and the outcomes employed to build the Bayesian Network in a linked chain of models. Hydrology-oriented forest management was very positive insofar as more water was made available to the stand because of an interception reduction. This resource was made available to the stand, which increased the evapotranspiration and its components, the soil water content and a slightly increase of deep percolation. Conversely, Stemflow was drastically reduced. No effect was observed on Runof due to the thinning treatment. The soil organic carbon content was also increased which in turn caused a greater respiration. The long-term effect of the thinning treatment on the LAI was very positive. This was undoubtedly due to the increased vigor generated by the greater availability of water and nutrients for the stand and the reduction of competence between trees. This greater activity resulted in an increase in GPP and vegetation carbon, and therefore, we would expect a higher carbon sequestration. It is worth emphasizing that this extra amount of water and nutrients was taken up by the stand and did not entail any loss of nutrients.

Are soluble carbohydrates ecologically relevant for salt tolerance in halophytes?

A general response of plants to high soil salinity relies on the cellular accumulation of osmolytes, which help the plant to maintain osmotic balance under salt stress condition and/or act as 'osmoprotectants' with chaperon or reactive oxygen species (ROS) scavenging activities. Yet the ecological relevance of this response for the salt tolerance mechanisms of halophytes in their natural habitats remains largely unknown. In this review, we describe and discuss published data supporting the participation of compatible solutes in those mechanisms, with especial focus on soluble carbohydrates. Evidence for a functional role of carbohydrates in salt tolerance include: (i) relatively high levels of specific sugars and polyols have been detected in many halophytic taxa; (ii) an increase in salt tolerance has often been observed in parallel with increased intracellular levels of particular soluble carbohydrates, in transgenic plants overexpressing the corresponding biosynthetic enzymes; (iii) there are several examples of genes involved in carbohydrate metabolism which are induced under salt stress conditions; (iv) specific sugars or polyols have been shown to accumulate in different halophytes upon controlled salt treatments; and (v) although very few field studies on environmentally induced carbohydrate changes in halophytes exist, in general they also support the involvement of this type of osmolytes in salt stress tolerance mechanisms. We also highlight the complexities of unequivocally attributing carbohydrates a biological role in salt tolerance mechanisms of a given tolerant species. It is proposed that research on halophytes in their natural ecosystems should be intensified, correlating seasonal changes in carbohydrate contents with the degree of environmental stress affecting the plants. This could be an important complement to experiments made under more controlled (but artificial) conditions, such as laboratory set-ups.

Antiinflammatory and immunomodulating properties of fungal metabolites.

We discuss current information on the ability of extracts and isolated metabolites from mushrooms to modulate immune responses. This can result in a more enhanced innate and acquired disease resistance. The major immunomodulating effects of these active substances derived from mushrooms include mitogenicity and activation of immune effector cells, such as lymphocytes, macrophages, and natural killer cells, resulting in the production of cytokines, including interleukins (ILs), tumor necrosis factor alpha (TNF)-alpha, and interferon gamma (INF)-gamma. In particular, the ability of selective mushroom extracts to modulate the differentiation capacity of CD4(+) T cells to mature into T(H)1 and/or T(H)2 subsets will be discussed. As a consequence these extracts will have profound effects in particular diseases, like chronic autoimmune T(H)1-mediated or allergic T(H)2-mediated diseases. Immunosuppressive effects by mushroom components have also been observed. The therapeutic effects of mushrooms, such as anticancer activity, suppression of autoimmune diseases, and allergy have been associated with their immunomodulating effects. However, further studies are needed to determine the molecular mechanisms of the immunomodulating effects of mushrooms metabolites both individually and in complex mixtures, for example, extracts.

Insecticidal activity of penitrems, including penitrem G, a new member of the family isolated from Penicillium crustosum.

Penitrem G (7), a new indole-diterpenoid compound, has been isolated together with the already known mycotoxins penitrems A-D (1-4) and F (6) from the mycelium of Penicillium crustosum Thom. The structure of penitrem G was established on the basis of spectroscopic data. In addition, paspaline (8), another indole-diterpenoid mycotoxin that has not been previously described in this fungus, was also isolated. These compounds were tested for insecticidal activity against the hemipteran Oncopeltus fasciatus Dallas and the dipteran Ceratitis capitata Wiedemann. Penitrems A-D and F showed convulsive and insecticidal activities against both insect species. In addition, important reductions in the fecundity and fertility of the surviving C. capitata females were observed. In contrast, penitrem G and paspaline did not show any kind of activity. Mortality data and sublethal effects of the treatments have allowed preliminary structure-activity relationships to be proposed.