Improving Soil Primary Productivity Conditions with Minimum Energy Input in the Mediterranean

Abstract

A collective well-succeed enterprise for good agriculture worldwide is possible through the synergetic effects of a series of favourable factors, among them, basically that associated to an adequate management of agricultural practices, improvement in soil tillage technologies, soil protection and conservation measures, animal and plant-breeding programs, genetic engineering and plant fertilization, all practices directed to augment the potential net production and productivity of the best biological varieties or cultivars available. A modern, intensive agricultural production system requires high levels of energy inputs, as compared to a traditional system. One should, for instance, just compare these two different production systems in terms of their global efficiency, but the IPS brought some negative environmental impacts, now diagnosed worldwide.

In the Mediterranean areas the seasonal distribution of precipitation is harmful to plant (crop) dry matter (DM) production which can be increased by adequately combining a good management of all input factors with a special care to natural resources protection, namely soil and water conservation.

In this work two fertile soils were managed under two alternative (TS = traditional mechanized system and DS = direct-seeding system) production systems during a ten-year period and their physical and chemical characteristics were compared in terms of agro-physical optimization to produce DM. The parameters that have been evaluated were: soil profile evolution texture and coarse elements, bulk density and soil resistance to the penetrometer, consistency limits; aggregates stability, organic matter (SOM) and nitrogen (N) contents and C/N ratio, cation-exchange capacity (CEC) and associated parameters, pores connectivity and soil-water retention curve.

From an agronomic perspective the DM production has been also estimated in order to evaluate the ecological sustainability of eventual improvements in soil-water conservation were justified by the alternative system.

Results enable to conclude that, inter alia, the alternative system under the perspective of the “Conservation Agriculture Paradigm” (Dumanski, R. et al., 2006) revealed to be prone to conserve more soil and water resources with interesting marginal gain in water and so in DM production. These results are well in the scope of the international concerns on adopting improved common policies for food security and problems associated to water scarcity, worldwide.