Species-specific efficiency in PM2.5 removal by urban trees: From leaf measurements to improved modeling estimates.

The growing population in cities is causing a deterioration of air quality due to the emission of pollutants, causing serious health impacts. Trees and urban forests can contribute through the interception and removal of air pollutants such as particulate matter (PM). The dry deposition of PM by vegetation depends on air pollutant concentration, meteorological conditions, and specific leaf traits. Several studies explored the ability of different plant species to accumulate PM on leaf structures leading to the development of models to quantify the PM removal. The i-Tree Eco is the most used model to evaluate ecosystem services provided by urban trees. However, fine particulate matter (PM2.5) removal is still calculated with a poorly evaluated function of deposition velocity (which depends on wind speed and leaf area) without differentiating between tree species. Therefore, we present an improvement of the standard model calculation introducing a leaf trait index to distinguish the species effect on PM net removal. We also compared model results with measurements of deposited leaf PM by vacuum filtration. The index includes the effect of morphological and functional leaf characteristics of tree species using four parameters: leaf water storage, deposition velocity, resuspension rate and leaf washing capacity. Leaves of 11 common urban tree species were sampled in representative areas of the city of Ferrara (Italy) and at different times of the year from 2018 to 2021. This includes four deciduous broadleaf trees (Tilia cordata, Platanus acerifolia, Acer platanoides, Celtis australis), three evergreen broadleaf trees (Quercus ilex, Magnolia grandiflora, Nerium oleander), and four conifers (Thuja orientalis, Cedrus libani, Pinus pinaster, Picea abies). The results provide significant advancement in assessing PM removal using decision support tools such as models to properly select tree species for future urban tree planting programs aimed at improving air quality.

The achievement of Water Framework Directive goals through the restoration of vegetation in agricultural canals.

Decreasing nitrate concentrations is one of the most relevant Water Framework Directive (WFD) goals, which today is still unreached in several European countries. Vegetated canals have been recognized as effective filters to mitigate nitrate pollution, although rarely included in restoration programs aimed at improving water quality in agricultural watersheds. The Po di Volano basin (713 km2, Northern Italy) is a deltaic territory crossed by an extensive network of agricultural canals (~1300 km). The effectiveness in buffering nitrate loads via denitrification was assessed for different levels of in-stream emergent vegetation maintenance by employing an upscale model based on extensive datasets of field measurements. The scenarios differed for the canal network length (5%, 20%, 40%, and 60%) where conservative management practices were adopted by postponing the mowing operations from the middle of summer, as nowadays, to the early autumn, i.e., the vegetative season end. The scenario simulations demonstrated that the capacity to mitigate diffuse nitrate pollution would increase up to four times, compared to the current condition (5% scenario), by postponing the vegetation mowing to the end of the vegetative season in 60% of the canal network length. By preserving the in-stream vegetation in 20% of the canal network, its denitrification capacity would equal the nitrate load reduction target required for achieving, from May to September, the good ecological status according to the WFD in waters delivered to the coastal areas. Changing the timing of vegetation mowing may create a large potential for permanent nitrate removal via denitrification in agricultural landscapes, thus protecting the coastal areas when the eutrophication risk is higher. Conservative management practices of in-stream vegetation might be promoted as an effective low-cost tool to be included in the WFD implementation strategies.

Plastic (PET) vs bioplastic (PLA) or refillable aluminium bottles - What is the most sustainable choice for drinking water? A life-cycle (LCA) analysis.

Nowadays, the most important tool to evaluate the environmental impact of both petro-plastics and bioplastics is the life cycle analysis (LCA). LCA determines the overall impact on the environment by defining, calculation and analyzing all the input and output directly related to production, utilization, and disposal of a product or a process. In this work, a LCA (cradle to grave) of bottles for drinking water was developed on three scenarios: polyethylene terephthalate (PET) bottles, as conventional packaging material for outdoor drinking water, polylactic acid (PLA) bottles, as alternative and innovative biodegradable packaging and aluminum bottle, as reusable and almost infinitely refilling packaging. As a result of LCA, ten impacts categories have been accounted for, among which the global warming potential (GWP, measured as kgCO2 eq), the eutrophication potential (EP, measured as kgPO4 eq.), human and eco-toxicity (HTP and ETP, measured as kg 1,4-DB eq.). The average drinking water consumption in Italy has been estimated in 1.5 L per day, corresponding to three 500 ml-plastic bottles and 1 refillable aluminum bottle. LCA has been firstly applied to a single bottle production and use, then to the daily and annual bottles consumption. PET bottles production and use assure the lower environmental impacts compared to PLA bottles, burdened by agricultural phase for corn cultivation, and to aluminum bottles, when the every-day washing with hot water or water and soap is comprehended. Moreover, including the end-of-life options into the analysis, PET recycling permits to reduce up to about 30% the GWP, whereas PLA composting does not lead to any GWP savings. In this study, aluminum bottle has been considered reusable for 2.5 years. The microbiological quality of water in one-way PET and PLA bottles has been compared with the refillable bottle rinsing with hot water and soap and only hot water, highlighting that the level of contamination is alarmingly increased in the latter case.

Nitrate availability affects denitrification in Phragmites australis sediments.

Understanding relationships between an increase in nitrate (NO3 - ) loading and the corresponding effects of wetland vegetation on denitrification is essential to designing, restoring, and managing wetlands and canals to maximize their effectiveness as buffers against eutrophication. Although Phragmites australis (Cav.) Trin. ex Steud. is frequently used to remediate nitrogen (N) pollution, no information is available on how NO3 - concentration may affect plant-mediated denitrification. In the present study, denitrification was measured in outdoor vegetated and unvegetated mesocosms incubated in both summer and winter. After spiking the mesocosms with NO3 - concentrations typical of agricultural drainage water (0.7-11.2 mg N L-1 ), denitrification was quantified by the simultaneous measurement of NO3 - consumption and dinitrogen gas (N2 ) production. Although denitrification rates varied with vegetation presence and season, NO3 - availability exerted a significant positive effect on the process. Vegetated sediments were more efficient than bare sediments in adapting their mitigation potential to an increase in NO3 - , by yielding a one-order-of-magnitude increase in NO3 - removal rates, under both summer (743-6007 mg N m-2 d-1 ) and winter (43-302 mg N m-2 d-1 ) conditions along the NO3 - gradient. Denitrification was the dominant sink for water NO3 - in winter and only for vegetated sediments in summer. Nitrification likely contributed to fuel denitrification in summer unvegetated sediments. Since denitrification rates followed Michaelis-Menten kinetics, P. australis-mediated depuration may be considered optimal up to 5.0 mg N L-1 . The present outcomes provide experimentally supported evidence that restoration with P. australis can work as a cost-effective means of improving water quality in agricultural watersheds.

Temporal dynamics of species associations in the parasite community of European eels, Anguilla anguilla, from a coastal lagoon.

The resilience of biological communities is of central importance in ecology, but is difficult to investigate in nature. Parasite communities in individual hosts provide good model systems, as they allow a level of replication usually not possible with free-living communities. Here, using temporal data (2005-2017) on the communities of endohelminth parasites in European eels, Anguilla anguilla, from brackish-water lagoons in Italy, we test the resilience of interspecific associations to changes in the abundance of some parasite species and the disappearance of others. While most parasite species displayed changes in abundance over time, three trematodes that were present in the early years, two of which at high abundance, completely disappeared from the parasite community by the end of the study period. Possibly other host species required for the completion of their life cycles have declined in abundance, perhaps due to environmental changes. However, despite these marked changes to the overall community, pairwise correlations in abundance among the three most common parasite species (all trematodes) were stable over time and remained mostly unaffected by what happened to other species. We explore possible reasons for these resilient species associations within a temporally unstable parasite community inhabiting a mostly stable host population.

The role of species introduction in modifying the functional diversity of native communities.

Although one of the most evident effects of biological invasions is the loss of native taxonomic diversity, contrasting views exist on the consequences of biological invasions on native functional diversity. We investigated this topic using Mediterranean stream, river and canal fish communities as a test case, at 3734 sites in Italy, and distinguishing between exotic and translocated species invasion in three different faunal districts. Our results clearly confirmed that introduced species were widespread and in many cases the invasion was severe (130 communities were completely composed by introduced species). Exotic and translocated fish species had substantially different geographical distribution patterns, perhaps arising from their differences in introduction timing, spread and invasion mechanisms. We also found a clear decreasing trend of functional dispersion along an invasion gradient, confirming our hypothesis that the invasion process can diminish the relative diversity of ecofunctional traits of host fish communities. Furthermore, our results suggested that exotic species might have a greater negative effect than translocated species on the relative diversity of ecofunctional traits of fish communities. This could also be linked to the fact that translocated species are more ecofunctionally similar to native ones, compared to the exotics. Our multivariate analysis of site-specific combinations of ecofunctional traits highlighted some traits characteristic of all invaded communities, while our discriminant analysis underlined how there was a substantial ecofunctional overlap between native, exotic and translocated species groups in most areas.

Could a freshwater fish be at the root of dystrophic crises in a coastal lagoon?

Eutrophication has a profound impact on ecosystems worldwide. Grass carp Ctenopharyngodon idella, an herbivorous fish, has been introduced to control aquatic plant overgrowth caused by eutrophication, but could have other, potentially detrimental, effects. We used the Po di Volano basin (south of the Po River delta, northern Italy) as a test case to explore whether grass carp effects on canal aquatic vegetation could be at the root of historical changes in N loads exported from the basin to the Goro Lagoon. We modeled the aquatic vegetation production and standing crop, its denitrification potential, and its consumption by introduced grass carp. We then examined whether changes in historical nitrogen loads matched the modeled losses of the drainage network denitrification function or other changes in agricultural practices. Our results indicate that introduced grass carp could completely remove submerged vegetation in the Po di Volano canal network, which could - in turn - lead to substantial loss of the denitrification function of the system, causing in an increase in downstream nitrogen loads. A corresponding increase, matching both timing and magnitude, was detected in historical nitrogen loads to the Goro Lagoon, which were significantly different before and after the time of modeled collapse of the denitrification function. This increase was not clearly linked to watershed use or agricultural practices, which implies that the loss of the denitrification function through grass carp overgrazing could be a likely explanation of the increase in downstream nitrogen loads. Perhaps for the first time, we provide evidence that a freshwater fish introduction could have caused long-lasting changes in nutrient dynamics that are exported downstream to areas where the fish is not present.

Perfluorooctanoic Acid Exposure Assessment on Common Carp Liver through Image and Ultrastructural Investigation.

Perfluorooctanoic acid (PFOA) poses particular concern as an emerging pollutant in both surface and ground waters. Fish, as a natural inhabitant of these waters and being highly representative of vertebrates, represents an ideal animal model to assess the toxic effects of PFOA. Hereby, liver microscopic texture was comparatively evaluated in individuals of common carp subchronically exposed to PFOA using grayscale differential box counting, a fractal analysis method. Furthermore, liver cytoplasmic glycogen areas and ultrastructure were also evaluated and compared to the image analysis findings. Redundancy Analysis was performed to assess, in summary, how much the variation of fractal dimension and lacunarity was explained by the concentration of PFOA in liver, the mass of liver and the number of proliferating cell nuclear antigen (PCNA)-immunoreactive nuclei. Treatment group ordination was better determined by fractal dimension than lacunarity. Interestingly, a significant complexity increase was associated with the modification of liver microscopic texture due to PFOA exposure. This complexity increase was related to "cloudy swelling", possibly representing a primarily adaptive strategy against PFOA challenge, rather than a slight, reversible form of degeneration as traditionally proposed. The occurrence of endoplasmic reticulum stress, unfolded protein reaction and hormetic response was proposed and discussed.

An ounce of prevention is worth a pound of cure: Managing macrophytes for nitrate mitigation in irrigated agricultural watersheds.

Although ubiquitous elements of agricultural landscapes, the interest on ditches and canals as effective filters to buffer nitrate pollution has been raised only recently. The aim of the present study was to investigate the importance of in-ditch denitrification supported by emergent aquatic vegetation in the context of N budget in agricultural lands of a worldwide hotspot of nitrate contamination and eutrophication, i.e. the lowlands of the Po River basin (Northern Italy). The effectiveness of N abatement in the ditch network (>18,500 km) was evaluated by extrapolating up to the watershed reach-scale denitrification rates measured in a wide range of environmental conditions. Scenarios of variable extents of vegetation maintenance were simulated (25%, 50% and 90%), and compared to the current situation when the natural development occurs in only 5% of the ditch network length, subjected to mechanical mowing in summer. Along the typical range of nitrate availability in the Po River lowlands waterways (0.5-8 mg N L-1), the current N removal performed by the ditch network was estimated in 3300-4900 t N yr-1, accounting for at most 11% of the N excess from agriculture. The predicted nitrate mitigation potential would increase up to 4000-33,600 t N yr-1 in case of vegetation maintenance in 90% of the total ditch length. Moreover, a further significant enhancement (57% on average) of this key ecosystem function would be achieved by postponing the mowing of vegetation at the end of the growing season. The simulated outcomes suggest that vegetated ditches may offer new agricultural landscape management opportunities for effectively decreasing nitrate loads in surface waters, with potential improved water quality at the watershed level and in the coastal zones. In conclusion, ditches and canals may act as metabolic regulators and providers of ecosystem services if conservative management practices of in-stream vegetation are properly implemented and coupled to hydraulic needs.

Estimate of gas transfer velocity in the presence of emergent vegetation using argon as a tracer: Implications for whole-system denitrification measurements.

Denitrification associated with emergent macrophytes is a pivotal process underlying the treatment performance of wetlands and slow-flow waterways. Laboratory scale experiments targeting N losses via denitrification in sediments colonized by emergent macrophytes require the use of mesocosms that are necessarily open to the atmosphere. Thus, the proper quantification of N2 effluxes relies on the accurate characterization of the air-water gas exchanges. In this study, we present a simple approach for direct measurements of the gas transfer velocity, in open-top mesocosms with Phragmites australis, by using argon as a tracer. Different conditions of water velocity (0, 1.5, 3, and 6 cm s-1) and temperature (8.5, 16, and 28 °C), were tested, along with, for the first time, the presence of emergent vegetation. The outcomes demonstrated that water velocity and temperature are not the only factors regulating aeration at the mesocosm scale. Indeed, the gas transfer velocity was systematically higher, in the range of 42-53%, in vegetated compared to unvegetated sediments. The increase of small-local turbulence patterns created within water parcels moving around plant stems translated into significant modifications of the reaeration process. The adopted approach may be used to improve the accuracy of denitrification measurements by N2 efflux-based methods in wetland and slow-flow waterway sediments colonized by emergent macrophytes. Moreover, the present outcomes may have multiple implications for whole-system metabolism estimations from which largely depend our understanding of biogeochemical dynamics in inland waters that have strong connections to worldwide issues, such as nitrate contamination and greenhouse gas emissions.

Run to the hills: exotic fish invasions and water quality degradation drive native fish to higher altitudes.

While the significance of anthropogenic pressures in shaping species distributions and abundances is undeniable, some ambiguity still remains on their relative magnitude and interplay with natural environmental factors. In our study, we examined 91 late-invasion-stage river locations in Northern Italy using ordination methods and variance partitioning (partial-CCA), as well as an assessment of environmental thresholds (TITAN), to attempt to disentangle the effects of eutrophication and exotic species on native species. We found that exotic species, jointly with water quality (primarily eutrophication) and geomorphology, are the main drivers of the distribution of native species and that native species suffer more joint effects than exotic species. We also found that water temperature clearly separates species distributions and that some native species, like Italian bleak (Alburnus alborella) and Italian rudd (Scardinius hesperidicus), seem to be the most resilient to exotic fish species. We also analyzed the dataset for nestedness (BINMATNEST) to identify priority targets of conservation. As a result, we confirmed that altitude correlated negatively with eutrophication and nestedness of exotic species and positively with native species. Overall, our analysis was able to detect the effects of species invasions even at a late invasion stage, although reciprocal effects seemed comparable at this stage. Exotic species have pushed most native species on the edge of local extinction in several sites and displaced most of them on the rim of their natural distribution. Any potential site- and species-specific conservation action aimed at improving this situation could benefit from a carefully considered prioritization to yield the highest results-per-effort and success rate. However, we encourage future research to update the information available before singling out specific sites for conservation or outlining conservation actions.

Space and time variations of watershed N and P budgets and their relationships with reactive N and P loadings in a heavily impacted river basin (Po river, Northern Italy).

The aim of the present study is to analyze relationships between land uses and anthropogenic pressures, and nutrient loadings in the Po river basin, the largest hydrographic system in Italy, together with the changes they have undergone in the last half century. Four main points are addressed: 1) spatial distribution and time evolution of land uses and associated N and P budgets; 2) long-term trajectories of the reactive N and P loadings exported from the Po river; 3) relationships between budgets and loadings; 4) brief review of relationships between N and P loadings and eutrophication in the Northern Adriatic Sea. Net Anthropogenic N (NANI) and P (NAPI) inputs, and N and P surpluses in the cropland between 1960 and 2010 were calculated. The annual loadings of dissolved inorganic nitrogen (DIN) and soluble reactive phosphorus (SRP) exported by the river were calculated for the whole 1968-2016 period. N and P loadings increased from the 1960s to the 1980s, as NAPI and NANI and N and P surpluses increased. Thereafter SRP declined, while DIN remained steadily high, resulting in a notable increase of the N:P molar ratio from 47 to 100. In the same period, the Po river watershed underwent a trajectory from net autotrophy to net heterotrophy, which reflected its specialization toward livestock farming. This study also demonstrates that in a relatively short time, i.e. almost one decade, N and P sources were relocated within the watershed, due to discordant environmental policies and mismanagement on the local scale, with frequent episodes of heavy pollution. This poses key questions about the spatial scale on which problems have to be dealt with in order to harmonize policies, set sustainable management goals, restore river basins and, ultimately, protect the adjacent coastal seas from eutrophication.

The effect of water velocity on nitrate removal in vegetated waterways.

The extended networks of canals and ditches in agricultural landscapes provide high buffer capacity towards nitrogen (N) excess. Their N mitigation potential depends on several biotic and abiotic factors, among which water velocity is poorly explored and generally omitted from the parameterization of this remarkable ecosystem service. The present work reports new insights on the role of flow velocity in regulating N removal via denitrification in sediments colonized by Phragmites australis. Denitrification was investigated in outdoor mesocosms in the presence and absence of P. australis and over a small range of flow velocity (0-6 cm s-1) typical of low-gradient water bodies. Simultaneous measurements of NO3- consumption and N2 production based on analyses of N2:Ar by Membrane Inlet Mass Spectrometry were undertaken. Vegetated sediments were found more efficient in converting NO3- to N2 via microbial-mediated denitrification (27-233 mmol N m-2 d-1) than bare sediments (18-33 mmol N m-2 d-1). Vegetation provides multiple interfaces, i.e. in the rhizosphere and on epiphytic biofilms, that support the development and activity of bacterial communities responsible for NO3- dissipation. NO3- removal and denitrification rates exhibited one order of magnitude raise when water velocity passed from 0 to 6 cm s-1 in vegetated sediments. Indeed, in slow-flow vegetated waterways denitrification may be physically limited and the increase of water velocity enhances the rate of NO3- supply through the diffusive boundary layer, thereby promoting its consumption and loss from the system. Water velocity should be taken into account as a key factor for management and restoration actions aimed at maximizing the NO3- buffer capacity of low-flow drainage networks.

Environmental doses of perfluorooctanoic acid change the expression of genes in target tissues of common carp.

We aimed to evaluate the effects of environmental doses of perfluorooctanoic acid (PFOA) on bioconcentration and gene expression in common carp (Cyprinus carpio). Adult male and female carp were exposed to environmental (200 ng/L) and experimental (2 mg/L) doses of PFOA for 56 d. Carp exposed to 200 ng/L had levels of PFOA below the level of detection in all tissue samples analyzed, whereas variable concentrations were measurable in various tissues from carp exposed to 2 mg/L. The expression level of the glutathione S-transferase (GST) gene, coding for a detoxifying enzyme, increased in a PFOA dose-dependent manner in liver tissues from 200 ng/L to 2 mg/L exposure (p < 0.05). The expression levels of CYP19A gene, coding for the enzyme that converts testosterone into estrogen, were altered in gonadal tissues from male and female carp exposed to either 200 ng/L or 2 mg/L; expression increased in male gonads and decreased in female gonads. Unexpectedly, the expression levels of CYP19A in male and female gonads from carp exposed to 200 ng/L or 2 mg/L were similar (p > 0.05). Therefore, even though environmental doses of PFOA did not accumulate in tissues of the common carp, they did affect the gene expression levels of GST in the liver and CYP19A in the gonads. These observations raise concerns that exposure to environmental doses of PFOA may affect gene expression in animals and possibly in humans, with important health consequences. Environ Toxicol Chem 2018;37:942-948. © 2017 SETAC.

Testing Spirotetramat as an Alternative Solution to Abamectin for Cacopsylla pyri (Hemiptera: Psyllidae) Control: Laboratory and Field Tests.

Aim of the study was to investigate the performance of the new insecticide "spirotetramat" as an alternative solution of "abamectin" for the control of Cacopsylla pyri L. (Hemiptera: Psyllidae) in the context of an IPM program in European pear, Pyrus communis L.. Laboratory bioassays for the estimation of LC50 and LC90 of both insecticides were performed using four populations collected in Emilia-Romagna (Italy) orchards where different pest management strategies were used (organic, integrated, and conventional). The same populations were also analyzed for the main insecticide detoxifying activities in nymphs by spectrofluorimetric in vitro assays. The performance of the two insecticides was also tested on field on one population under integrated pest management conditions. The laboratory experiments showed that the LC90 of spirotetramat were lower than the highest field concentration allowed in Europe (172.80 mg AI liter(-1)) giving reassurance about the efficacy of the product. Concerning the abamectin, the laboratory bioassays did not show strong indications of resistance development of C. pyri populations of Emilia-Romagna. A similarity in enzyme detoxifying activity was observed in both insecticides indicating a general absence of a significant insecticide resistance. The field trial showed a high efficacy (>90 %) of spirotetramat on C. pyri already after 15 d from application, and it was significantly higher from abamectin. Overall, spirotetramat is one more choice for C. pyri control, as well as abamectin in order to minimize the risks of occurrence of insecticide resistance.

Occurrence of perfluorooctanesulfonate and perfluorooctanoic acid and histopathology in eels from north Italian waters.

A perfluorinated alkylated substances (PFAS) biomonitoring study was conducted in European eel (Anguilla anguilla) in Italy for the first time. Perfluorooctanesulfonate (PFOS) and perfluorooctanoic acid (PFOA) concentrations were assessed in the organs of 35 wild eels from two locations, the highly impacted Po River and the Comacchio Lagoon along the north-western Adriatic coast. PFAS were extracted by ion-pairing liquid extraction procedure and measured using high performance liquid chromatography with electrospray ionization tandem mass spectrometry. There were no significant differences in mean PFAS concentrations (p>0.05) between samples from the two sites. PFOS and PFOA were detectable (>0.4ngg(-1) wet weight, w.w) in 73% and 31% of the total samples, respectively. PFOS concentrations ranged from <0.4 to 6.28ngg(-1)w.w and PFOA from <0.4 to 92.77ngg(-1)w.w. The highest PFAS levels were observed in blood and the lowest in muscle. Histology showed macrophage aggregates and hepatocytic vacuolation in some liver samples. No tissue anomalies were seen in the gonads, suggesting no reproductive impairment. The PFAS contamination levels observed were comparable to, or lower than, those reported in fish in other European countries, seeming to indicate that PFAS pollution of the study area is not remarkable.

An EPG study of the probing behavior of adult Bemisia tabaci biotype Q (Hemiptera: Aleyrodidae) following exposure to cyantraniliprole.

Cyantraniliprole is a novel insecticide for control of multiple chewing and sucking insect pest species including the sweetpotato whitefly Bemisia tabaci (Gennadius), which is one of the most important polyphagous pests in tropical, subtropical, and Mediterranean regions. This study aims to evaluate the effects of cyantraniliprole on the probing behavior of B. tabaci on tomato. Electrical penetration graph data indicated that on plants treated with cyantraniliprole (foliar application), adult whiteflies of the genetic variant Q2 were not able to reach the phloem and consequently did not perform the activities represented by E1 and E2 waveforms, i.e., phloem salivation (during which inoculation of geminiviruses occurs) and phloem sap ingestion (during which geminiviruses are acquired by the whiteflies), respectively. The complete failure of B. tabaci biotype Q adults to feed from the phloem of tomato plants treated with cyantraniliprole could be explained by rapid cessation of ingestion because of the mode of action of this insecticide. Overall, these findings indicated that cyantraniliprole might represent a useful new tool for producers to protect tomato plants from damage by B. tabaci.

Assessment of insecticide resistance of Lobesia botrana (Lepidoptera: Tortricidae) in Emilia-Romagna region.

The European grapevine moth, Lobesia botrana (Denis & Schiffermüller) (Lepidoptera: Tortricidae), is the key pest of vineyard, Vitis vinifera L. In Italy, failures in field chemical pest control have been recently reported. The susceptibility to insecticides indoxacarb, methoxyfenozide, and emamectin benzoate was then evaluated in a L. botrana population collected from a vineyard in Emilia-Romagna (northeastern Italy) where pest management programs achieved unsatisfactory results. The field trial showed that the indoxacarb efficacy toward L. botrana was very low in the two timings of application (7.9 and -1.5%) in comparison with untreated control, while the efficacy of methoxyfenozide (76.1%) and emamectin benzoate (88.8%) was high. The decreased efficacy of indoxacarb was also supported by the results of the laboratory bioassay on neonate L. botrana larvae, in which the resistance ratio was 72-fold in comparison with that of the susceptible strain.

Nitrogen budget in a lowland coastal area within the Po River basin (northern Italy): multiple evidences of equilibrium between sources and internal sinks.

Detailed studies on pollutants genesis, path and transformation are needed in agricultural catchments facing coastal areas. Here, loss of nutrients should be minimized in order to protect valuable aquatic ecosystems from eutrophication phenomena. A soil system N budget was calculated for a lowland coastal area, the Po di Volano basin (Po River Delta, Northern Italy), characterized by extremely flat topography and fine soil texture and bordering a network of lagoon ecosystems. Main features of this area are the scarce relevance of livestock farming, the intense agriculture, mainly sustained by chemical fertilizers, and the developed network of artificial canals with long water residence time. Average nitrogen input exceeds output terms by ~60 kg N ha(-1) year(-1), a relatively small amount if compared to sub-basins of the same hydrological system. Analysis of dissolved inorganic nitrogen in groundwater suggests limited vertical loss and no accumulation of this element, while a nitrogen mass balance in surface waters indicates a net and significant removal within the watershed. Our data provide multiple evidences of efficient control of the nitrogen excess in this geographical area and we speculate that denitrification in soil and in the secondary drainage system performs this ecosystemic function. Additionally, the significant difference between nitrogen input and nitrogen output loads associated to the irrigation system, which is fed by the N-rich Po River, suggests that this basin metabolizes part of the nitrogen excess produced upstream. The traditionally absent livestock farming practices and consequent low use of manure as fertilizer pose the risk of excess soil mineralization and progressive loss of denitrification capacity in this area.