Treated cattle wastewater affects the growth, quality and water productivity of Dalbergia nigra seedlings produced with shading and irrigation levels

Abstract

The continuous demand for water in the agricultural sector has encouraged researchers worldwide to find alternatives to optimize this resource. The use of wastewater in irrigation is promising in this scenario, especially to produce tree seedlings. The growth, quality, and water productivity of Dalbergia nigra seedlings cultivated with sewage sludge were determined when irrigated with urban supply water (W 1 ) and cattle wastewater (CWW) treated for 1 h (W 2 ) and 2 h (W 3 ) of ozonation, considering four irrigation depths and shading levels (0 % (C 1 ), 37.6 % (C 2 ), 49.4 % (C 3 ), 75.8 % (C 4 )). The height, stem diameter, biomass, and the Dickson Quality Index (DQI) were evaluated. The largest volumes of water applied in each experiment were 2.342 L per plant in W 2 C 1 , 2.114 L per plant in W 1 C 3 and 1.556 L per plant in W 3 C 1 . The CWW provided satisfactory seedling growth, especially W 2 , highlighting a DQI of 0.47 obtained in C 1 and better water productivity (3.8 g L -1 ) in W 2 C 1 , with full depth.Using alternative inputs in the seedling production of tree species is a promising strategy and indicates benefits for waste disposal, such as sewage sludge and wastewater.