Photo 2: Livestock utilising mult-specie cover crops through ultra-high dencity grazing
drastically enhances the impact of diversity
producers to reduce the use of fertilisers,
while sustaining good and stable yields and
increasing profitability. This understanding is
important if we wish to sustain productivity
at the lowest possible costs, both economic
and ecological. Without being able to go
into details, this paper aims to provide a few
principles, advantages and examples of ISFM.
Integrated soil fertility management
This concept of ISFM emphasizes the
maximization of nutrient use efficiency,
the enhanced access of soil nutrients to
plant roots, the response of soil as a living
ecosystem and the role of sound locally
adapted soil management practices enhancing
ecosystem functions and services leading
to improved soil fertility. The concept
acknowledges that neither practices based
solely on mineral fertilizers nor solely on
soil ecosystems services are enough for
sustainable crop production, especially during
the transition years after starting with CA on
degraded soils. It also requires well-adapted,
disease- and pest-resistant germplasm, as
well as other GAPs. The critical soil ecosystem
processes involved are transformations of
carbon, cycling of nutrients, maintenance
of the structure and fabric of the soil, and
biological regulation of soil populations.
(NUE)
Nutrient use efficiency, which may be defined
as the yield obtained per unit of available
nutrients in the soil (supplied by the soil +
fertilisers), could be improved as follows:
o Adjustment of fertiliser application rates
based on (natural) soil fertility levels taking
account of SOC level, organically bonded
nutrients, nutrient cycling and/or previous
cropping practices, especially legumes, and
their residue biomass.
o Apply fertiliser at the right time and place
and using the right source.
o Plant crops at the right planting density
having enough plants to ensure optimal
and efficient nutrient access and yield. In
CA higher planting densities (around 30%
higher than the norm) or at least above
22 000 p/ha ensures effective use of soil
nutrients and water in the whole soil
profile and surface area, while reducing
temperature at soil surface level.
CA Principles and practices enhancing ISFM
Many producers world-wide have achieved
large improvements in soil health in a
relatively short time. What are these farmers
doing differently?
Ways to increase nutrient use efficiency
AgriKultuur |AgriCulture
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