Organic matter amendments improve soil fertility in almond orchards of contrasting soil texture

Abstract The effects of organic matter amendments (OMA) on soil fertility in permanent cropping systems like orchards is under-studied compared to annual systems. We evaluated experimentally the impact OMAs almond ( Prunus dulcis ) over a two-year period with applications. Two OMAs, derived from composted green waste (GWC) or manure wood chips (MWC), were applied as surface mulch and control at two sites different textures (sandy loam loamy sand). increased moisture content (0–0.1 m depth) both by 27–37%. Both inorganic N sandy (GWC: 194%; MWC: 114%) sand 277%; month following application, but concentrations quickly decreased values similar those plots. After two-years, GWC MWC cation exchange capacity (CEC) 112% 29%, respectively, site, no change was observed site. greatest increase extractable K occurred GWC-amended plots site even though initial concentration higher. carbon (SOC) after years, SOC greater. Our results suggest that can significantly improve one applications, gains appear be dependent texture than nutrient OMA.