Saline water consumption by plants in most cases affects crops yield in their various stages hampering development and production. The study evaluated rucola (Eruca sativa) water consumption in NFT hydroponic system using saline water. We analyzed six increasing levels of salinity (electrical conductivity), which are: 0.2; 1.2; 2.2; 3.2; 4.2 and 5.2 dS m-1, two salt sources were used, brackish waters (AS) and NaCl. Volume was determined by plant evapotranspiration (VETc) in the system during cultivation. The water consumption during the first days after transplantation decreased with the increase of salinity levels. The amount of water was 250 mL day-1 for treatment without saline water. The water efficiency was reduced revealing a linear decreasing function of salinity occurring in a negative response of plants showing a reduction of sheets number of 3.34%.

The northeastern semiarid region faces some of the droughts of the last centuries, resulting in serious reductions of agriculture yields. The water scarcity for agricultural requires rational use practices and reuse of water, such as use of domestic effluent sewage. Alternatively, the use of treated domestic sewage effluent utilizing for irrigation of forage species, such as the forage cactus, can be highlighted. In order to evaluate the effects of fertirrigation with treated sewage effluent on mineral nutrient composition of forage cactus (Opuntia Tuna L. Mill, Mexican elephant ear), an experiment was carried out utilizing a split plot 3 x (4 + 1) with a randomized complete block design randomized block and four replications, being three planting density (66,667.00, 52,282.00 and 33,333.00 plants ha-1) and two water sources associated with irrigation frequency of plates fixed on 3.5 mm per irrigation (Frequencies of 2.3 days with water tap and 7, 14 and 21 days with Sewage Effluent) and cactus cultivated in Rainfed agriculturerainfed (control). The analyze of the nutritional contents of cladodes indicated that there was a significant effect of the intervals from irrigation events only for Ca and Mg concentrations. The highest levels of Ca and Mg were found with the irrigation frequency of 2.3 using tap water. The macronutrients concentration in greater quantity by the forage cactus were N e, K followed by, Ca, Mg and P. The nutritional balance indicated excess of K and P and deficiency of N, Ca and Mg, in this order.

Groundwater with high salt concentrations is common in the semiarid region of Brazil. It often makes them inappropriate to conventional agricultural production of vegetables. Therefore, the objective of this work was to evaluate watercress and Chinese cabbage crops under a nutrient film technique (NFT) hydroponic system using brackish groundwater. The experiment was carried out in the Poço do Boi region, in Ibimirim, Pernambuco, Brazil (8º32'15"S, 37º41'30"W, and altitude of 431 m). The treatments used were: public water (T1), calcium sulfate water (T2), magnesium chloride water S1 (T3), calcium chloride water (T4), sodium chloride water (T5), and magnesium chloride water S2 (T6). A completely randomized experimental design was used, with six treatments and four replications, totaling 24 plots for each crop. The fresh and dry shoot weights and rates of relative and absolute growths were analyzed. The different waters used affected negatively the growth and yield of the watercress and Chinese cabbage plants. The calcium chloride water was the most suitable for the watercress production. However, none of the groundwaters used could be recommended for production of Chinese cabbage. The lowest growth rates (5.88% to watercress and 0.75% to Chinese cabbage) of the fresh matter were found with the use of magnesium water.

Irrigation with brackish water is common in the semiarid region of the Brazilian Northeast, potentiating the process of salinization of the soil in these areas. The hydroponic system stands out as an important strategy for crop management in semiarid regions, since crops show greater tolerance to the salt stress under hydroponic conditions, which minimize the effects of soil salinization. Thus, the objective of this work was to evaluate the effects of salt stress on the growth, fruit yield and mineral nutrition of sweet pepper in hydroponic system, using brackish water and coconut fiber substrate. The experiment was conducted in Recife, State of Pernambuco, Brazil (8°3'15''S, 34°52'53''W). A randomized block experimental design in a 5x2 factorial arrangement with five replications was used, consisting of five water salinity levels of the nutrient solution (2.0; 3.5; 4.5; 5.5 and 6.5 dS m-1) and two sweet pepper cultivars (Bruno and Rubia). The increasing salinity level of the nutrient solution decreased the fruit yield of the cultivars evaluated, reduced the potassium, phosphorus and sulfur, and increased the sodium and chlorine contents in the leaf tissues. The Ca contents of the cultivar Bruno decreased with increasing salinity, and increased in the cultivar Rubia. The cultivar Rubia stood out with the highest fruit yield and ionic selectivity, accumulating high amounts of potassium and calcium and maintaining low Na and Cl contents. The fruit yield of the cultivar Rubia (39.9 t ha-1) grown under solution with electrical conductivity of up to 3.5 dS m-1, denotes the potential viability of growing this cultivar under hydroponic conditions.

Soil is the habitat for a number of living organisms that perform essential functions within the ecosystem; their functions and interactions are modified according to different ways of land occupation. Thus, the objective of this study was to evaluate the diversity of edaphic fauna in different soil occupation systems. The study was carried out in different soil occupation systems: millet, maize, soybean, eucalyptus, preserved cerrado, disturbed cerrado, and pasture, with 130 pitfall traps installed per treatment. Soil fauna organisms were identified at the level of large groups (orders and family), and then examined under the following biological diversity indices: Shannon index, Pielou index, average and total richness, and abundance. The highest abundance was found under millet growing conditions (9,974 individuals), and the lowest abundance values were found in soybean soil (222 individuals) and maize (824 individuals). Uniform distribution of groups in the area with soybean crops, due to the homogeneous management of the area, provided the highest biological index (H'=2.69). Principal component analysis (PCA) explained 50.9% of the data along the main axis and 34.6% of the data along the secondary axis. The different systems of soil occupation showed different abundance and diversity, demonstrating how soil occupation interferes with the dynamics of the invertebrate soil fauna.