Usina hidrelétrica na amazônia e impactos socioeconômicos sobre os pescadores do município de Ferreira Gomes – Amapá

Socioeconomic impacts of the construction of the Ferreira Gomes Hydroelectric Power Plant (UHEFG) were analyzed in communities of fishermen affected before and after the filling of the reservoir. The study occurred between 2014 and 2015, in the municipality of Ferreira Gomes-AP. Data were collected using forms (Nsample=48) and a comparative analysis was performed to evaluate their significance (Mann-Whitney, p<0.05). The results showed that the Environmental Impact Assessment (EIA) did not adequately predict impacts in the fisheries sector. The comparative tests confirmed a) six variables with significant variation (p<0.05): monthly income, number of trips to fish, fishing difficulties, environmental conditions of the Araguari River, socioeconomic and environmental impacts; and b) a variable at the limit of significance (p≈0,056): fish trade. We concluded that the reparatory measures did not reestablish the socioenvironmental conditions, generating conflicts not foreseen.Os impactos socioeconômicos da construção da Usina Hidrelétrica de Ferreira Gomes (UHEFG) foram analisados ​​em comunidades de pescadores afetados antes e depois do enchimento do reservatório. O estudo ocorreu entre 2014 e 2015, no município de Ferreira Gomes-AP. Os dados foram coletados por meio de formulários (Nsample = 48) e uma análise comparativa foi realizada para avaliar sua significância (Mann-Whitney, p <0,05). Os resultados mostraram que o Estudo de Impacto Ambiental (EIA) não previu adequadamente os impactos no setor pesqueiro. Os testes comparativos confirmaram a) seis variáveis ​​com variação significativa (p <0,05): renda mensal, número de viagens para pescar, dificuldades de pesca, condições ambientais do rio Araguari, impactos socioeconômicos e ambientais; e b) uma variável no limite de significância (p≈0,056): comércio de pescado. Concluímos que as medidas reparatórias não restabeleceram as condições socioambientais, gerando conflitos não previstos

Use of ammonium sulphate as a sulphur fertilizer: Implications for ammonia volatilization

Ammonium sulphate is widely used as a sulphur (S) fertilizer, constituting about 50% of global S use. Within nitrogen (N) management it is well known that ammonium-based fertilizers are subject to ammonia (NH3) volatilization in soils with pH >7, but this has been overlooked in decision making on S fertilization. We reviewed 41 publications reporting measurements of NH3 loss from ammonium sulphate in 16 countries covering a wide range of soil types and climates. In field experiments loss was mostly 7.0 there was a wide range of losses (0-66%), with many in the 20-40% range and some indication of increased loss (ca. 5-15%) in soils with pH 6.5-7.0. We estimate that replacing ammonium sulphate with a different form of S for arable crops could decrease NH3 emissions from this source by 90%, even taking account of likely emissions from alternative fertilizers to replace the N, but chosen for low NH3 emission. In temperate climates emission from soils of pH >7.0 would decrease from 35.7 to 3.6 t NH3 per kt ammonium sulphate replaced. Other sources of S are readily available including single superphosphate, potassium sulphate, magnesium sulphate, calcium sulphate dihydrate (gypsum) and polyhalite (Polysulphate). In view of the large areas of high pH soils globally, this change of selection of S fertilizer would make a significant contribution to decreasing NH3 emissions worldwide, contributing to necessary cuts to meet agreed ceilings under the Gothenburg Convention