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Human activities as land use and management impact soil functioning. These are amplified also by stress factors as extreme climate events (drought, flood, heat waves) and meteorological anomalies, consequence of climate change. Although there are clues on how these challenging factors affect quality and functioning at its top surface (between 0 - 15 cm), there are minor information on how these impact soil in its depth profile. This study present obtained data from assessment studies performed on agricultural lands managed under different conditions, targeting especially applied pesticides degradation rate under pressures of management activities and climate change associated stress factors. Briefly, soil sample cores with 0-100 cm depth were collected from different agricultural land where different management, respectively different pesticides were applied in order to facilitate crops production rate. Experience on artificially incubated and exposed soil throughout simulating different meteorological anomalies (excess or reduced watering, increased or low temperature, etc.) were also conducted, and compared with data from field experiences. Also, targeted pesticide fate and degradation pattern was evaluated connecting them with different soil quality parameter as soil physicochemical properties, microbial biomass and extracellular enzymatic activities. Fate of identified transformation products of pesticides were also monitored and compared with data obtained from real field studies. Beside that monitored pesticide characteristics influence strongly their decay rate and entirely pathways, it was observed that microbial biomass vary strongly between soil samples depending also by soil types and properties. Additionally, both microbial biomass and extracellular enzymatic activities of soil present a strong decay (over 50%) once with soil depth profile. However, enzymatic activities were observed even in the deeper part of soil cores (over 30 cm), parts of soil that usually are not monitored. Temperature and soil moisture were observed to influence soil extracellular enzymatic activities, which in turn impact used pesticides decay rate. [ABSTRACT FROM AUTHOR]

A new organic nonlinear optical (NLO) material from the chalcone family: (2E)-1-(3,4-dichlorophenyl)-3-[4-(methylsulfanyl)phenyl]prop-2-en-1-one (DPMS) is crystallised in DMF solution. The functional groups in DPMS are identified by FTIR spectra. The thermal stability is studied using TGA/DTA. The polymethylmethacrylate (PMMA) film doped with DPMS was prepared. Direct and indirect band gap energy of DPMS doped PMMA is determined using U. V. Visible spectra. The nonlinear absorption coefficient and optical power limiting of the film was studied using Z-scan technique. The film exhibits a self focussing effect at a wavelength of 532nm. The results of optical limiting studies, shows that the film possesses reverse saturable absorption due to excited state absorption. The nonlinear optical properties of DPMS have been retained in the presence of a polymer material. [ABSTRACT FROM AUTHOR]