E. R. Porto

Rendimento da Atriplex nummularia irrigada com efluentes da criação de tilápia em rejeito da dessalinização de água

Looking forward to reduce environmental impacts resulting from desalinization of brackish water in the region of the crystalline rocks in the semi-arid Brazil, saltbush (Atriplex nummularia) was cultivated during one year with four different volumes of aquiculture effluent generated from an intensive tilapia (Oreochromis sp) raising system, with a mean salinity of 8.29 dS m-1, in an experimental field of Embrapa Semi-Arid. A completely randomized block design, with four treatments and three replications was used. The treatments T1, T2, T3 and T4 corresponded, respectively, to the weekly volumes of irrigation of 75, 150, 225 and 300 L of water per plant. The mean soil salinity of the cropped area, in the depth of 0 - 90 cm, was 0.40 dS m-1 before starting the irrigation process. After the plants were harvested, the mean soil salinity in the profiles was 8.02, 6.09, 4.97, and 4.60 dS m-1 for treatments T1, T2, T3 and T4, respectively. The saltbush dry matter yields were 9.75, 12.26, 14.49 and 13.81 t ha-1 for treatments T1, T2, T3 and T4, respectively. The highest dry matter production per unit of applied water was for treatment T1, which yielded 4.84 g L-1 of effluent. The same treatment had the best relation input/output of salt by the saltbush, removing 13.84% of the total salt incorporated into the soil.

Atividade microbiana em solo do Semi-Árido sob cultivo de Atriplex nummularia

Methods used to estimate the soil microbial activity are important to environmental monitoring of degraded areas. The objective of this research was to investigate the microbial activity of a semiarid soil cultivated with Atriplex nummularia Lindl. in a field receiving saline waste during one and three years, in comparison with an area without crop and irrigation. Soil cultivated during three years presented, during the dry season, values of pH, CE, and activity of FDA hydrolyses higher than those registered in other areas. However, a negative correlation between the microbial carbon and values of qCO2 was observed. The microbial biomass and the alkaline phosphates were also higher in the three years cultivated soil, in comparison with the native soil, non irrigated, confirming the role of halophytes for enhancing quality of soils under saline stress. Thus, the cultivation of A. nummularia is an alternative for using saline waste from the desalinization process.

Feno de Erva-Sal (Atriplex nummularia Lindl.) e Palma Forrageira (Opuntia ficus Mill.) em Dietas para Caprinos e Ovinos

Objetivou-se avaliar a composicao quimico-bromatologica, o consumo e a digestibilidade de nutrientes de dieta composta por palma forrageira ( Opuntia ficus ) e feno de erva-sal ( Atriplex nummularia ) por caprinos e ovinos. Foram utilizados doze animais, sendo seis caprinos e seis ovinos, todos machos, castrados, com peso vivo medio inicial de 25 kg. Os animais foram alojados em baias individuais durante 15 dias, sendo dez dias de adaptacao e cinco de coleta de dados. A palma forrageira e o feno de erva-sal foram os unicos alimentos oferecidos a vontade aos animais, na proporcao de 50% da materia seca por animal, duas vezes ao dia, com livre acesso a agua e sal mineral. A dieta apresentou 55,76% de materia seca (MS), 77,88% de materia orgânica (MO), 22,54% de materia mineral (MM), 7,07% de proteina bruta (PB), 1,12% de extrato etereo (EE), 39,92% de fibra em detergente neutro (FDN), 20,05% de fibra em detergente acido (FDA), 19,87% de hemicelulose (HEM), 69,27% de carboidratos (CHOT) e 29,34% de carboidratos nao fibrosos (CNF). Observou-se diferenca significativa, para o consumo de MS, PB, FDN, FDA, MO, MM, EE e agua; com maiores valores verificados para os ovinos. Com relacao ao coeficiente de digestibilidade verificou-se que houve diferenca significativa para FDA, MM, MS, FDN e MO entre caprinos e ovinos com maiores valores verificados para os caprinos. Concluiu-se que os ovinos apresentaram uma melhor aceitabilidade, enquanto, os caprinos mostraram um melhor aproveitamento dos nutrientes contidos na dieta.