Subsoil constraints to grain production in the cropping soils of the north-eastern region of Australia: an overview

摘要: In dryland agricultural systems of the subtropical, semi-arid region north-eastern Australia, water is most limiting resource. Crop productivity depends on efficient use rainfall and available stored in soil during fallow. Agronomic management practices including a period fallow, stubble retention, reduced tillage enhance reserves water. However, access to these soils may be restricted by presence growth-limiting conditions rooting zone crop. These have been termed as subsoil constraints. Subsoil constraints include compacted or gravel layers (physical), sodicity, salinity, acidity, nutrient deficiencies, toxic elements (chemical) low microbial activity (biological). Several occur together some soils. Farmers often not able obtain potential yield determined their prevailing climatic marginal areas northern grains region. past, adoption had largely top 100 mm layer. Exploitation source nutrients has overlooked. The key towards realising yields would gain better understanding subsoils limitations, then develop options manage them practically economically. Due complex nature causal factors constraints, efforts are required for combination approaches rather than individual options, with aim combat sustainable crop production, managing natural resources avoiding environmental damage.