Patterns of Distribution of Bivalve Populations in a Mediterranean Temporary River

In the south of the Iberian Peninsula, many rivers are intermittent, a state most likely to be exacerbated by climate change, strongly affecting river biota. An additional challenge for native biota in this area is the arrival of new species, frequently aided by humans, and bivalves are particularly at risk. Here we assessed whether the native (Unio delphinus) and invasive (Corbicula fluminea) bivalves differed in habitat use. To address this question, we sampled populations of both species in six isolated permanent pools in the same river during summer in three consecutive years. U. delphinus occurred in all pools, while C. fluminea occurred only in the two most downstream pools. U. delphinus, but not C. fluminea, was found preferentially in patches under riparian vegetation cover. Both species were found in similar sediment types (coarse and fine gravel respectively). Although U. delphinus was present in all pools, recruitment was detected only in 2016, in one pool. We concluded that both species have the potential to compete for space, but a well-developed riparian vegetation cover may provide U. delphinus some advantage against C. fluminea

Doenças da cultura da melancia em Rondônia.

O trabalho reúne informações sobre as principais doenças que ocorrem na melancia (Citrullus lanatus) e seus prejuísos às plantações do Estado de Rondônia.bitstream/item/23259/1/Cot298-melancia.pd

Cradle-to-gate assessment of bacterial cellulose production

In an increasing environmental conscious world, Life Cycle Assessment (LCA) is an important tool for estimate environmental impact of processes and products. This work aims to determine the environmental impacts of the production of bacterial cellulose (BC) intended to be used as a food additive. BC is a biopolymer produced mainly by Gram-negative acetic acid bacteria such as Glunoacetobacter xylinum. BC structure consist in glucose monomers arranged in a unique nanostructure, exhibiting numerous great properties, leading to wide range of applications in different areas including as a food product or as food addictive, and in high-value-added niche markets such as medical applications and cosmetic industry[1]. The LCA (cradle-to-gate) was simulated in GaBi Software (ThinkStep), using ReCiPe 2016 method to estimate the Life Cycle Impact Assessment (LCIA). LCIA translates emissions and resource extractions into a limited number of environmental impact scores (environmental impact categories) by means of the so-called characterization factors. The study includes not only the production of BC, the energy and the equipment used, but also the extraction of natural resources and their transformation and the disposal of the produced waste (Cradle-to-gate). The functional unit of this LCA was defined as 1 kg of BC packed in a plastic container and a carton box. Results presented in 18 midpoints impact categories show that the sodium hydroxide, carton package, and plastic package productions are responsible for considerable impacts. The production of sodium hydroxide and carton package are also responsible for considerable amount of water resources and emissions to the environment.info:eu-repo/semantics/publishedVersio