Soil erosion, runoff and nutrient losses in an avocado (Persea americana Mill) hillside orchard under different groundcover management systems

Abstract

Aims Assess the influence of different groundcover management systems on erosion and runoff processes associated with extremely steep hillside avocado (Persea americana Mill) orchards, in a Mediterranean climate with high rainfall variability. Methods We compared several groundcover management systems at a steep hillside avocado planting in a three-year study: 1) Bare soil (BS), pre-and postemergence herbicides; 2) Vegetation strip (VS), postemergence herbicide applied in a 1-m wide strip on the tree row plus groundcover seeded between tree rows; 3) Groundcover (GC), over the entire plot surface. Results Trees in the BS plots were 44 and 53 % bigger, and had 150 and 250 % higher yields than trees in VS and GC, respectively. Runoff volumes, soil losses, dissolved organic carbon, PO 4 -P and total N losses were significantly higher in BS than VS and CG treatments. Total soil nitrogen (N) and carbon (C) content, C-to-N ratios, and essential plant nutrient availability were greater in the GC soil than in other treatments. Soil macroporosity and aggregate stability were 8-27 % and 25 % lower, and soil bulk density significantly higher in the BS than the VS and GC systems at the end of the study. Terbuthylazine herbicide concentrations in runoff water from BS plots ranged from 55.4 to 79.9 μgL −1 , exceeding maximum allowed levels for drinking water (0.1 μgL −1 ). Conclusion Soil erosion and runoff rates from newly planted hillside orchards are not environmentally sustainable under current growing practices where groundcover vegetation is completely suppressed. High sediment losses and herbicide residues in runoff water present serious risk of water source pollution, but these impacts can be reduced by alternative soil management systems.

Clay and Phosphorus Losses by Erosion in Oxisol With Sugarcane Residues

“…The vegetation coverage influence on erosion rate was also studied by ATUCHA et al (2013) who observed that the vegetation with ryegrass in avocado orchards minimized the erosion in 99.96%, as well as other environmental impacts, reducing nutrient losses by runoff in 79.7% for N and in 94.1% for P, comparing to the bare soil. In this research, the reductions in losses of P were in order of 66.7% with SC of 100% in relation to the bare soil.…”

“…Agríc., Jaboticabal, v.36, n.6, p.1063-1072, nov./dez. 20161064 The impacts caused by erosion can be minimized by using alternative soil cultivation systems (ATUCHA et al, 2013), among them the use of conservation systems that keep the waste on the surface and no soil preparation (TRUMAN et al, 2009). …”

Effects of soil management techniques on soil water erosion in apricot orchards

“…High erosion rates have been observed in avocado (Atucha et al, 2013) and olive orchards (Gómez et al, 2003;Vanwalleghem et al, 2010), new citrus plantations (Cerdà et al, 2009b;Li et al, 2015) and vineyards (Novara et al, 2013;Tarolli et al, 2015). Almond (Faulkner, 1995), persimmon , and apricot (Abrisqueta et al, 2007) orchards have also shown high erosion rates, but little research has been carried out comparing agriculture land management in fruit orchards.…”

Land use impact on overland flow: micro-scale field experimental analysis

“…/jwld-2016 by MOŢOC et al [1975], IONIŢĂ et al [2006], MIRCEA et al [2010;, MAETENS et al [2012]; hydrological: PETRESCU [1974], STANCIU [2002], YU et al [1997], BENAVIDES-SOLORIO, MACDONALD [ , JOEL et al [2002; forestry by ABAGIU et al [1973], HARTANTO et al [2003]; biological factors [WAIN-WRIGHT et al 2000]; ecologic by GBUREK and SHAR-PLEY [1998], DEBANO [2000], COVINO et al [2010], ATUCHA et al [2013].…”