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21.
The Common Agricultural Policy (CAP) is the European Union's main instrument for agricultural planning, with a new reform approved for 2023–2027. The CAP intends to align with the European Green Deal (EGD), a set of policy initiatives underpinning sustainable development and climate neutrality in the European Union (EU), but several flaws cast doubts about the compatibility of the objectives of these 2 policies. We reviewed recent literature on the potential of CAP environmental objectives for integration with the EGD: protection of biodiversity, climate change mitigation and adaptation, and sustainable management of natural resources. The CAP lacks appropriate planning measures, furthering instead risks to biodiversity and ecosystem services driven by landscape and biotic homogenization. Funding allocation mechanisms are not tailored to mitigate agricultural emissions, decreasing the efficiency of climate mitigation actions. The legislation subsidies farmers making extensive use of synthetic inputs without adequately supporting organic production, hindering the transition toward sustainable practices. We recommend proper control mechanisms be introduced in CAP Strategic Plans from each member state to ensure the EU is set on a sustainable production and consumption path. These include proportional assignment of funds to each CAP objective, quantitative targets to set goals and evidence-based interventions, and relevant indicators to facilitate effective monitoring of environmental performance. Both the CAP and the EGD should maintain ambitious environmental commitments in the face of crisis to avoid further degradation of the natural resources on which production systems stand.  相似文献   
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This paper studies the degradation reactions that 4-chloroaniline can naturally undergo in waters for the action of sun light. 10.00 mg L−1 4-chloroaniline aqueous solution, without any addition of organic solvent, are undergone to photoirradiation under conditions that simulate sun light. The degradation pathway, followed by HPLC-DAD-MS/MS methods, is complex since the pollutant gives rise to many photoproducts: the predominant species are characterized by m/z values of 217 (P5) and 218 (P6) and are compatible with dimeric structures of 4-chloroaniline. Vibrio fischeri tests indicate that the photoproducts of 4-chloroaniline are characterized by a toxicity level significantly greater than the precursor.  相似文献   
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Marbofloxacin (MAR) and Enrofloxacin (ENR), two largely employed veterinary Fluoroquinolones (FQs), were found to be present at the micrograms per kilogram level in agricultural soils of South Lombardy (Italy) several months after manuring. Distribution coefficients (Kd) from sorption experiments indicated a strong binding to the soil. Soil samples fortified with environmentally significant FQs amounts (0.5 mg kg−1) were exposed to solar light that promoted extensive degradation (80%) of both drugs in 60-150 h. Thus, photochemistry could be considered a significant depollution path in the soil, although it was two orders of magnitudes slower than in aqueous solution and a fraction of the drug (ca. 20%) remained unaffected. For MAR the photoprocess was the same as in solution, and involved cleavage of the tetrahydrooxadiazine ring. On the contrary, with ENR only some of the photoproducts determined in water (those arising from a stepwise oxidation of the piperazine side chain) were observed. Substitution of the 6-fluoro by a hydroxyl group and reduction did not occur in the soil, supporting the previous contention that such processes required polar solvation of FQs. Consistently with this rationalization, the irradiation of thin layers of solid drugs led to essentially the same products distribution as in the soil. From the environmental point of view it is important to notice that photodegradation mainly affects the side-chains, while the fluoroquinolone ring, to which the biological effect is associated, is conserved up to the later stages of the degradation.  相似文献   
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The evolution of ozone (O 3) in the nocturnal and morning-transitional planetary boundary layer (PBL) of the Phoenix valley was measured as a part of the `Phoenix Sunrise Experiment 2001' of the U.S. Department of Energy conducted in June 2001. The goal of the field program was to study the transport, distribution and storage of ozone and its precursors in the urban boundary layer over a diurnal cycle. The ground level O 3 as well as mean meteorological variables and turbulence were measured over the entire period, and vertical profiling (using a tethered balloon) was made during the morning transition period. Approximately half of the observational days showed the usual diurnal cycle of high O 3 during the day and low O 3 at night, with nitrogen oxides (NO x = NO 2 + NO) showing an out of phase relationship with O 3. The rest of the days were signified by an anomalous increase of O 3 in the late evening ( 2200 LST), concomitant with a sudden drop of temperature, an enhancement of wind speed and Reynolds stresses, a positive heat flux and a change of wind direction. NO x measurements indicated the simultaneous arrival of an `aged' air mass, which was corroborated by the wind predictions of a mesoscale numerical model. In all, the results indicate that the recirculation of O 3 rich air masses is responsible for the said high-O 3 events. Such air masses are produced during the transport of O 3 precursors by the upslope flow toward mountainous suburbs during the day, and they return back to the city at night via downslope winds (i.e. mountain breeze). The corresponding flow patterns, and hence the high-O 3 events, are determined by background meteorological conditions. The vertical profiling of O 3 and flow variables during the morning transition points to a myriad of transport, mixing and chemical processes that determine the fate of tropospheric O 3. How well such processes are incorporated and resolved in predictive O 3 models should determine the accuracy of their predictions.  相似文献   
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We developed a dynamic model of the phosphorus cycle in Lake Chozas, a small shallow water body in León (NW Spain). The calibrated model simulated seasonal dynamics of phosphorus concentrations in major components of the lake's ecological network before and after 1997, the year when an invasive allochthonous crustacean, the Louisiana red swamp crayfish (Procambarus clarkii), was introduced into the lake. The shift from clean to turbid phase, due to grazing by crayfish on submerged vegetation, caused a gradual decrease in eco-exergy, reflecting an increase in entropy, related to breakdown of ecosystem internal equilibria. This case study verifies the hypothesis of Marchi et al. (2010) that, after an initial relatively stable state, the allochthonous species may cause an increase in entropy indicating perturbation of the ecosystem.  相似文献   
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Environmental Science and Pollution Research - Trace elements are widespread contaminants that can potentially threaten ecosystems and human health. Considering their distribution and toxicity,...  相似文献   
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Environmental Science and Pollution Research - Pharmaceuticals and their degradation products which are present in wastewater and superficial waters are becoming an ecological issue. This research...  相似文献   
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