IOSR Journal of Biotechnology and Biochemistry (IOSR-JBB) ISSN: 2455-264X, Volume 6, Issue 1 (Jan. – Feb. 2020), PP 58-69 www.iosrjournals.org DOI: 10.9790/264X-0601015869 www.iosrjournals.org 58 | Page Earlier Observation of Applicability of Biomolecular and Chemical Analysis to Soil and Shallow Groundwater in Nitrogen Biogeochemical Local Cycle Evaluation Angelantonio Calabrese 1 , Laura Mandrelli 1 and Massimo Blonda 1 1 (National Research Council (CNR), Water Research Institute, Bari, Italy) Abstract: The presence of nitrate in groundwater has long been considered as one of the main issues on a global scale. The identification of various contamination sources is then particularly relevant, along with the assessment of the negative impact of agricultural activities. This work presents the first attempt to apply the developed methodologies to phenomena of groundwater contamination from nitrates, with the purpose of distinguishing the type of contamination when related to particular microbiomes environments of soil and shallow groundwater. Analyses of the main chemical parameters and of the microbiome involved in the nitrogen biogeochemical cycle were carried out through specific definition of metagenomics techniques. The analytical procedure adopted, implemented with further quantitative real-time to estimate specific microbial communities in different matrices, showed to be suitable for the identification of factors responsible for nitrate contamination. In addition, it provides useful information on the relationship and possible interaction between soil and groundwater. Interesting differences emerge between the possible chemical and microbiological exchange between soil and groundwater, and the quality of soil itself, due to different agronomic practices a soil use. Future application of the Real Time and the quantification of population abundance per species will allow more detailed information about these phenomena. Key Word: Nitrogen biogeochemical cycle, soil, shallow groundwater, biomolecular technique, nitrate pollution. --------------------------------------------------------------------------------------------------------------------------------------- Date of Submission: 30-01-2020 Date of Acceptance: 17-02-2020 --------------------------------------------------------------------------------------------------------------------------------------- I. Introduction Groundwater is one of the main Earth’s freshwater resources for industrial processes, agricultural activities and human life. Nitrogen compounds are the major chemicals artificially released into the environment as a consequence of the growing need for food and energy production [1] [2]. Several studies have highlighted how the excessive use of fertilizers generates a surplus of fertilizer compared to the farms real need. In these cases, the nitrates present in fertilizers can be easily washed off by rainfall and irrigation, with possible consequent formation of high nitrate concentrated polluted plumes in groundwater, following hydrodynamic dispersion [3][4][5][6]. Another anthropic source of nitrates is the sewage, mainly from small towns or isolated houses, in the absence of a collection grid [8]. Livestock is another leading contributing factor [8]. For all the above mentioned reasons, nitrates are the form of nitrogen most frequently exceeding the maximum admissible concentrations in groundwater set at 50 mg/lby the Directive 91/676/CEE. Today is well known that the whole subsoil system is colonized by microorganisms, mainly present in microbial communities, constituted of bacteria and Archaea, but also of protozoa and fungi, carrying out relevant roles in biogeochemical processes [9]. The groundwater ecosystems are affected by the presence of environmental limiting factors (lack of light, limited nutrient availability, low temperatures, etc.) conditioning the existence of peculiar microbial communities [10]. Microbial communities in the aquifers are constituted of Heterotrophic bacteria well adapted to underground environment [11] [12] [13] and they characterize the hydrological, chemical and geological heterogeneity of the groundwater [11] [12]. The presence of different biotic and abiotic factors may directly or indirectly influence the microbial diversity of ecosystems, determining three different dynamics of transformation of micro biotic communities: quantitative variation of certain bacteria strains already present therein; appearance of new strains of alien bacteria; disappearance of some bacteria strains. Moreover, depending on the type of alteration (from diffuse