Protection of Water Resources from Agriculture Pollution: An Integrated Methodological Approach for the Nitrates Directive 91–676-EEC Implementation

Nitrogen is a vital nutrient helpful to plants and crop growth. However, among the leading causes of water resources pollution is the excess nitrogen from agricultural sources. In European Union countries, the Nitrates Directive has been approved to reduce this problem monitoring of water bodies with regard to nitrate concentrations, designation of Nitrate Vulnerable Zones (NVZs), and establishing codes of good agricultural practices and measures to prevent and reduce water pollution from nitrates. In light of this, we propose an integrated methodological approach to better manage a environmental issue as the perimeter of NVZs with the prospective that our approach could be used in the future by other member states representing a Best Practice in that direction. The methodology is based on data integration applied in a GIS environment. Different available data representing the knowledge of the territory were harmonised, systematised and georeferenced, in order to increase the environmental framework, preserve the contamination of the water resource and give indications on the measures to be implemented to apply in the best way possible the Nitrates Directive. Finally, it was also possible to overcome the infringement procedure in progress for Italy and the Puglia region and proceed to new designation of NVZs.

Validation of bacterial markers to discriminate against the source of nitrate contamination: a promising application within the EU Nitrates Directive

The European Community (EC) Nitrates Directive (ND) (Council Directive 1991/676/EEC) aims to avoid water pollution by nitrates from poor farming practices. Under the ND, Nitrate Vulnerable Zones (NVZs) have been defined as areas where the concentration of agricultural nitrates in surface or groundwater exceeds 50 mg/L. Groundwater is one of the main sources of drinking water in Europe, so ensuring its quality is of significant importance. Monitoring of water parameters, the identification of pollution, the development of good agricultural practice codes is included in ND as measures and action programs. ND provides for the attribution of areas affected by nitrate pollution to the NVZ in which farmers must comply with measures necessary to reduce nitrogen in excess and protect the quality of environmental matrices. However, in some cases the quality of water bodies remains poor, suggesting that some action measures are ineffective or need improvements. Nevertheless, nitrates in excess in groundwater might be related to industrial inputs, untreated waste discharge, and sewage spilling. Due to this, identifying non-agricultural contributions to nitrate groundwater pollution can be of great interest. With this aim, the employment of biomarkers such as microbes associated with the intestinal tract of a specific host is under study for identifying fecal pollution. This strategy is known, in scientific literature, as Microbial Source Tracking (MST)(Furtula et al. 2011)The amplification of 16S rRNA genes of host-specific Bacteroidales allows discriminating against human and livestock fecal sources in samples from nitrate polluted environment. The aim of this work is to evaluate the sensitivity and specificity of these intestinal biomarkers in groundwater samples collected along with the Apulian Region (Southern Italy) in order to assess the applicability of the MST in the employ of ND. A preliminary study was carried out to validate the performance of seven markers for MST using two different approaches: Polimerase Chain Reaction (PCR) and quantitative Real-time PCR (qPCR) assays. For both PCR and qPCR experiments selected primer sets were checked using fecal samples of known origin as positive controls. PCR assay was used for human (HF74 and Enterococcus faecalis) (Bernhard and Field 2000, Jackson et al. 2004), cattle (CF123) (Bernhard and Field 2000), equine (HoF597) (Dick et al. 2005), and pig (Pig163) (Dick et al. 2005) markers screening. Two additional markers were tested through Real-time PCR: human (Human- Bacteroides) (Seurinck et al. 2005) and zootechnical (BacPre I) (Kobayashi et al. 2012). The results indicate that biomarkers can be considered reliable in distinguishing human from animal pollution. Nevertheless, our studies show that the tests conducted with the human Enterococcus faecalis biomarker do not discriminate the zootechnical source from the human one. In some cases, PCR-tested biomarkers cannot determine the source of contamination in environmental matrices due to the detection limit. Animal and human fecal markers were widely detected on eleven groundwater samples through Real Time PCR, highlighting the prevalent source of contamination in the environmental matrix. This research provides evidence that MST technology is a valid tool for local authorities to identify the source of nitrate contamination and review uncertainties during the NVZs definition and the action program development required by the European Nitrate Directive.

A novel LUMNAqSoP approach for prioritising groundwater monitoring stations for implementation of the Nitrates Directive

Background The Nitrates Directive (ND) is an EU anti-pollution legislative that, for almost 30 years, has controlled and protected hydro-resources against excessive levels of nitrates originating from agroecosystems, striving to prevent the further exacerbation of the nitrates in aquatic environments. ND sets several principal goals that member states must accomplish, such as performing spatiotemporal nitrate analyses in ground/surface water networks to achieve national water quality monitoring programme. Results In this study, using the novel LUMNAqSoP approach, the prioritisation of 151 candidate groundwater stations for ND monitoring in Croatia was performed. The LUMNAqSoP integratively evaluates: (i) the most dominant loads from the agroecosystem (land use and management, net nitrogen application) and (ii) environmental (aquifer and soil) vulnerabilities and sensitivities of groundwater resources to nitrate pollution. By comparing stations which scored the most agro-environmental loads vs. the data from water stations containing elevated mean nitrate concentrations (from existing monitoring programmes) a very good agreement was confirmed. Moreover, deviations close to large urban zones were detected, suggesting that elevated nitrates in groundwaters in those areas likely originated from municipal/industrial rather than agricultural sources; however, further studies are needed for elucidation. Conclusions The presented approach can serve as a useful tool to policy makers and regulators for: (i) more efficient and reliable establishment of water monitoring programme pursuant to ND, as well as (ii) better management and shaping (designating/derogating) of nitrate-vulnerable zones, especially in diverse environmental conditions and dynamic agroecosystems as have been confirmed in recent decades across the EU member states.

Influence of the Shortening of the Winter Fertilization Prohibition Period in Hungary Assessed by Spatial Crop Simulation Analysis

The Nitrates Directive aims (a) to protect water quality across Europe from nitrates originating from agricultural sources that pollute ground and surface water, and (b) to promote good farming practices. One of the most controversial measures of the directive is the winter prohibition period of fertilization, which has been extended by a month in two steps in recent years. According to the regulation, it is forbidden to apply nitrogen fertilization in Hungary between 31st October and 15th February, even though the winter climate is gradually becoming milder. Using the fertilization data of nearly half a million parcels of land in the Hungarian Nitrate Database, a crop model-based spatial analysis was carried out. Our aim was to test if a shift in the prohibition period starting date from 31st October to 30th November caused any differences in the nitrate amount leached at a 90 cm depth. Detailed nitrate inputs and soil and weather databases were coupled with the 4M crop model. The yield, plant nitrogen uptake, and nitrate leaching under five major crops were simulated, covering a considerable portion of arable land. Shifting the prohibition period starting date did not result in significant changes in the nitrate leaching. Further runs of the 4M model with different weather scenarios are needed to decide whether the modification of the prohibition period significantly affects the amount of nitrate leached.

Assessment of Nitrate Hazards in Umbria Region (Italy) Using Field Datasets: Good Agriculture Practices and Farms Sustainability

The Nitrates Directive, EU 91/676/EEC, obliged all European Union member states to introduce laws that guarantee the use of proper agriculture and farm methods, with the aim to reduce pollution resulting from the excessive use of nitrates. In this work, we estimated the potential and effective nitrogen load from agriculture, farms, civil, and industrial sources in Umbria region, Italy, and assessed the previous (and actual) contamination by nitrates at different scales. The adopted methodology uses databases of the sources, such as the type of fertilizer (inorganic or manure), the type of industrial site, the census of livestock and field data at a local, basin, and regional scale. Hydrological and geological models are used to compute infiltration. The study shows that the contribution of farms to nitrate pollution is in the order of swine > cattle > sheep and goats; while the highest agricultural load is due to arable land, followed by olive and grape. The study also shows that municipalities that have values of nitrates over the threshold for both groundwater and surface water can rapidly change their status during consecutive years. This means that rules for farm sustainability, complying with the Nitrates Directive, EU 91/676/EEC, should be defined at a sub-basin scale, where the hydrogeological conditions strongly influence infiltration.

The Wicked Problem of Diffuse Nutrient Pollution from Agriculture

Diffuse nutrient pollution from agriculture has been the concern of policymakers for several decades, and yet it remains a persistent environmental issue. The current approach to mitigating the problem is predominantly via command and control regulation within the Nitrates Directive and the Water Framework Directive. This article will set out how diffuse pollution can be considered a wicked policy problem which acts as an explanation of how it has eluded the current regulatory regime. It will further establish that the traditional planning process overlooked the complexity of the problem. Finally, it will illustrate the ineffectiveness of the current regulatory framework to mitigate the problem. This will be exemplified through the legal framework of Northern Ireland.

Nitrate Management Discourses in Poland and Denmark—Laggards or Leaders in Water Quality Protection?

The most significant source of nitrate pollution in the European Union (EU) is attributed to agricultural activities, which threaten drinking water, marine, and freshwater resources. The Nitrates Directive is a key feature of the Water Framework Directive (WFD), which seeks to reduce nitrate pollution from agricultural sources. Yet, weak compliance by Member States (MS) diminishes the legitimacy of the EU environmental acquis and undermines efforts to achieve environmental objectives. This study examines the nitrate management discourse in Poland to identify influencing factors that impact governance capacity and overall compliance performance. The empirical investigation is based on nine stakeholder interviews, three written correspondences, and a literature review that collectively comprise an evaluation study. A comparison in governance approaches between Poland and Denmark provides a calibration in assessing performance respective to another MS. The findings categorize both Poland and Denmark as “laggard” in WFD compliance. This case contributes new insights in identifying 6 enabling and 13 constraining factors affecting the ability of MS to fulfill their implementation duties. The findings demonstrate that divergent stakeholder views based on historical and cultural norms require a differentiated approach tailored to domestic conditions for effective fulfillment of the objectives set forth in EU environmental legislation.

The role of the agricultural sector in the legal system of national reductions of air pollution in the European Union under Directive 2016/2284 NEC

The aim of the article is to define the role of the agricultural sector in the legal systems of national emissions ceilings in the European Union, and in particular the requirements of the amended legal basis in this respect – Directive No 2016/2284 of 14 December 2016 on the reduction of national emissions of certain atmospheric pollutants, amending Directive 2003/35/EC and repealing Directive 2001/81/EC. This law, in addition to the Nitrates Directive, is currently one of the most important regulations of EU law on protection against environmental pollution from agricultural sources. Among the pollutants covered by the reduction obligation under Directive 2016/2284 NEC, ammonia is the most critical pollutant of agricultural origin, hence the crucial importance for agriculture of the measures aimed at reducing emissions of this substance. These measures are mainly of an optional nature and it is up to the Member States to determine how to achieve the national reduction target. It is therefore necessary to design the right mix of measures and match them with the different types of agricultural activities when developing relevant national strategies. It is also necessary to combine them with other regulations, in particular on industrial emissions and water protection, and to address the issues of nitrogen circle in a systemic manner, not only at farm level but also throughout the entire food chain.

Pump and treat optimization schemes for nitrate removal from a rural basin aquifer

<p>Lake Karla aquifer, with extent of 500 km<sup>2</sup>, is located at the eastern part of the most cultivated region of Greece, Thessaly, where water demanding crops prevail. The last three decades is under a status of quantitative and qualitative degradation because of the long-term intense agricultural activities, the lack of any significant surface water body and of an organized irrigation network. About 80% of the pumped groundwater is used for irrigation. According to Lake Karla recreation project fifty wells have been established at the southern part of the aquifer in order to cover the drinking water needs for the nearby city of Volos. This area is characterized by the greatest depletion of aquifer’s water table and by high values of nitrate concentrations in groundwater resources.  The area is one of the seven vulnerable zones of Greece, with respect to nitrogen pollution from agricultural run-off, according to the requirements of the Nitrates Directive (91/676/EEC).</p><p>The study proposes a pump and treat optimization method for nitrates removal from the supply wells area with the use of a simulation-optimization modelling system through two scenarios regarding nitrate fertilization of crops during the remediation period:</p><ol><li>The crops receive the same amount of fertilizers as applied in the historical period.</li> <li>The crops receive the amount of fertilizers defined by the Nitrates Directive (91/676/EEC).</li> </ol><p>The classification of crop types at the study area of aquifer is implemented with the use of a Geographical Information System (GIS). Nitrate leaching to aquifer is achieved through water infiltration from surface to subsurface system and has been estimated to 40% of nitrogen fertilizer application. The simulation-optimization modelling system applied, consists of a groundwater simulation model (MODFLOW), a groundwater transport and a dispersion simulation model (MT3DMS) and a management model (GWM). The optimization problem targets to the minimization of the operation cost of pump and treat wells, subject to plume stabilization through reversing the hydraulic heads slope and to keeping the values of nitrate concentration in the supply wells area lower than the threshold of 25 mg/L introduced by Nitrates Directive. Pump and treat wells are proposed to be located at the boundary of the urban supply wells area, where the plume crosses it.  The historical period is from 1995 to 2007, while the remediation period starts on 2007.</p><p>The results indicate that, for the first scenario, the pump and treat wells must operate through the whole remediation period (2007-2017) since great volumes of nitrate pollutants continuously leach to aquifer concluding to high operation costs equal to 372.47 thousands of euros. On the contrary, for the second scenario, the remediation period is decreased to four years resulting to an operational cost lower than the half of the additional of the first scenario equal to 147.09 thousands of euros. These results highlight the importance of the full compliance with Nitrates Directive requirements by the farmers of rural basins, where the groundwater resources are used for potable use; otherwise any remediation design will be costly.</p>