In rain-fed cropping, defining the best combination of practices could achieve high forage yield and silage quality. The aim of this study was to compare energetic quality of produced silage with productive characteristics of forage maize cultivated on alluvium and hydromorphous black soil in rain-fed conditions at four plant densities (68-74,000 plants ha-1) during the period 2005- 2010. Yield and energy parameters were increased to some extent at higher crop densities indicating that higher densities (74,000 plants ha-1) were potentially better for high forage and DM yields, while lower densities (70,000 plants ha-1) were better for the increase of energy parameters of produced silage. [Projekat Ministarstva nauke Republike Srbije, br. TR-31037]

Environmental context Various UV-filtering chemicals are added to sunscreens in order to protect humans from the harmful effects of the sun. As a consequence of disinfection processes in swimming pools, sunscreen components may be chlorinated and change their structure and properties, leading to derivatives with higher toxicity. The safety of sunscreen components as well as that of their transformation products during their use requires further study. Abstract In this work is presented a synthesis pathway for the UV filter hexyl 2-(4-diethylamino-2-hydroxybenzoyl)benzoate (DHHB) and its chlorinated by-products in order to investigate the transformation behaviour and toxicity changes of DHHB during chlorination disinfection treatment. Acute toxicity was measured using standardised tests with aquatic model organisms. The potency of DHHB was compared with other benzophenone-like UV filters tested in the same experimental set-up. The toxicity of chlorinated compounds tested with photobacteria was found to be in a similar range to that of the starting compound. Microalgae were more sensitive to DHHB than to its chlorinated by-products, whereas daphnids were affected more by DHHB’s chlorinated products. The comparative toxicity data showed DHHB and even more its chlorinated by-products as more highly biologically potent to daphnids than other tested UV filters. The toxic potential of benzophenone-like UV filters should be interpreted together with data on their chemical properties, chlorination effects and affected organisms.