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The phytoremediation potential of four crop species cultivated on carbonation lime coming from the sugar industry with water-soluble nickel (Ni) exceeding the Italian legal limit of 10 µg L−1 was assessed. Two autumn–winter species (spinach and canola) were tested with and without the addition of bentonite in a greenhouse experiment in order to overcome prolonged unfavourable weather conditions. Two spring-summer species (sunflower and sorghum) were grown in outdoor boxes. Plant species were selected among crops of interest for phytoremediation and their rotation throughout the year enable to maintain a permanent vegetation cover. Nickel concentration in different plant tissues and the concentrations of soluble and bioavailable Ni in lime were measured. In the greenhouse study, soluble Ni decreased below the legal limit in all the tests, and the combined effect of bentonite and plants reduced Ni in lime mainly in the bioavailable fraction. Spinach and sunflower emerged to be more suitable for phytoextraction than canola and sorghum, because of the higher concentration of the metal in the epigeal portions. The results from the outdoor experiment highlighted that sorghum has a good phytostabilisation potential since its ability to accumulate Ni mainly at the root level and to attract a significant amount of bioavailable Ni in the rhizosphere. This study arose from a real scenario of environmental contamination and investigated the potential of different approaches on the bioremediation of a specific industrial waste product.

This review describes the researches performed in the last years to assess the impact of pesticide sub-lethal doses on soil microorganisms and non-target organisms in agricultural soil ecosystems. The overview was developed through the careful description and a critical analysis of three methodologies based on culture-independent approaches involving DNA extraction and sequencing (denaturing gradient gel electrophoresis, DGGE; next-generation sequencing, NGS) to characterize the microbial population and DNA damage assessment (comet assay) to determine the effect on soil invertebrates. The examination of the related published articles showed a continuous improvement of the possibility to detect the detrimental effect of the pesticides on soil microorganisms and non-target organisms at sub-lethal doses, i.e., doses which have no lethal effect on the organisms. Considering the overall critical discussion on microbial soil monitoring in the function of pesticide treatments, we can confirm the usefulness of PCR-DGGE as a screening technique to assess the genetic diversity of microbial communities. Nowadays, DGGE remains a preliminary technique to highlight rapidly the main differences in microbial community composition, which is able to give further information if coupled with culture-dependent microbiological approaches, while thorough assessments must be gained by high-throughput techniques such as NGS. The comet assay represents an elective technique for assessing genotoxicity in environmental biomonitoring, being mature after decades of implementation and widely used worldwide for its direct, simple, and affordable implementation. Nonetheless, in order to promote the consistency and reliability of results, regulatory bodies should provide guidelines on the optimal use of this tool, strongly indicating the most reliable indicators of DNA damage. This review may help the European Regulation Authority in deriving new ecotoxicological endpoints to be included in the Regi

Biopurification systems (BPS) have been introduced to minimise the risk for point source contamination of natural water resources by pesticides. Their depuration efficiency relies mostly on the high biodegradation of their packing substrate (biomixture). Despite that, little is known regarding the interactions between biomixture microflora and pesticides, especially fungicides which are expected to have a higher impact on the microbial community. This study reports the dissipation of the fungicides azoxystrobin (AZX), fludioxonil (FL) and penconazole (PC), commonly used in vineyards, in a biomixture composed of pruning residues and straw used in vineyard BPS. The impact of fungicides on the microbial community was also studied via microbial biomass carbon, basal respiration and phospholipid fatty acid analysis. AZX dissipated faster (t 1/2 = 30.1 days) than PC (t 1/2 = 99.0 days) and FL (t 1/2 = 115.5 days). Fungicides differently affected the microbial community. PC showed the highest adverse effect on both the size and the activity of the biomixture microflora. A significant change in the structure of the microbial community was noted for PC and FL, and it was attributed to a rapid inhibition of the fungal fraction while bacteria showed a delayed response which was attributed to indirect effects by the late proliferation of fungi. All effects observed were transitory and a full recovery of microbial indices was observed 60 days post-application. Overall, no clear link between pesticide persistence and microbial responses was observed stressing the complex nature of interactions between pesticides in microflora in BPS.

New modeling approaches that include the use of GIS are under development in order to allow a more realistic assessment of environmental contamination by pesticides. This paper reports a regional GIS-based risk assessment using a software tool able to simulate complex and real crop rotations at the regional scale. A single pesticide leaching assessment has been done. The mean annual pesticide concentration in leachate has been analyzed using both stochastic and deterministic approaches. The outputs of these simulations were mapped over the sampling locations of the regional pesticide monitoring program, demonstrating that GIS-based risk assessment can be used to establish new monitoring programs. A multiple pesticide leaching assessment for analyzing the risk related to pest control strategies in six different maize-based rotations has been carried out. Additive toxic units approach has been used. Crop rotation allows to mediate the risk related to pesticide use because forces the use of different compounds with different fate and toxicology properties. © 2008 American Chemical Society.

In a 2-year lysimeter experiment, the effect of urea-N in the presence of the nitrification inhibitor 3,4-dimethylpyrazole phosphate (DMPP) on the yield and nitrate uptake of flooded and nonflooded rice was examined in comparison with N-fertilized and unfertilized plots. Results show that although DMPP doesn’t increase either the dry matter at different stages of development or the mean grain yield, it may improve grain quality reducing markedly NO3-N concentration. The positive effect of DMPP on grain quality was evident in both irrigation systems but it was especially pronounced in flooded conditions where PO4-P content significantly increased

A lysimeter experiment on flooded and nonflooded rice was conducted to evaluate the effect of urea-N in the presence of the nitrification inhibitor 3,4-dimethylpyrazole phosphate (DMPP) on the fertilizer 15N recovery during different growth stages. At tillering and at panicle differentiation percent recoveries of fertilizer 15N in the nonflooded management were greater in the presence of DMPP, whereas they were significantly lower under flooding conditions. The recovery of fertilizer N was the highest at panicle differentiation under either water regimes. At maturity, the supplying of DMPP ameliorated the partitioning of accumulated total N and of fertilizer 15N applied at panicle differentiation among vegetative and reproductive tissues under nonflooded regime; however, the influence of the nitrification inhibitor was insignificant under flooding