Abstract
A soil nutrient balance is a commonly
used indicator to assess changes in soil fertility. In
this paper, an earlier developed methodology by
Stoorvogel and Smaling to assess the soil nutrient
balance is given a major overhaul, based on
growing insights and advances in data availability
and modelling. The soil nutrient balance is
treated as the net balance of five inflows (mineral
fertilizer, organic inputs, atmospheric deposition,
nitrogen fixation and sedimentation) and five
outflows (crop products, crop residues, leaching,
gaseous losses and erosion). This study aims to
improve the existing methodology by making it
spatially explicit, improving various transfer functions, and by modelling explicitly the uncertainties in the estimations. Spatially explicit
modelling has become possible through a novel
methodology to create a simulated land use map
on the basis of the principles of traditional
qualitative land evaluation. New literature data
on the various inputs and outputs allowed
improvement of the estimations of deposition,
sedimentation, leaching, and erosion. Moreover,
the uncertainty of the calculated soil nutrient
balances was assessed. To illustrate the
improved methodology, we applied it to Burkina
Faso and revealed that nutrient depletion is
occurring throughout the country at rates
of 20 15 kg N ha-1
, 3:7 2:9 kg P ha-1 and
15 12 kg K ha-1
. The resulting spatial soil
nutrient balances at the national level can constitute the basis for targeting soil fertility policies at
lower levels.
used indicator to assess changes in soil fertility. In
this paper, an earlier developed methodology by
Stoorvogel and Smaling to assess the soil nutrient
balance is given a major overhaul, based on
growing insights and advances in data availability
and modelling. The soil nutrient balance is
treated as the net balance of five inflows (mineral
fertilizer, organic inputs, atmospheric deposition,
nitrogen fixation and sedimentation) and five
outflows (crop products, crop residues, leaching,
gaseous losses and erosion). This study aims to
improve the existing methodology by making it
spatially explicit, improving various transfer functions, and by modelling explicitly the uncertainties in the estimations. Spatially explicit
modelling has become possible through a novel
methodology to create a simulated land use map
on the basis of the principles of traditional
qualitative land evaluation. New literature data
on the various inputs and outputs allowed
improvement of the estimations of deposition,
sedimentation, leaching, and erosion. Moreover,
the uncertainty of the calculated soil nutrient
balances was assessed. To illustrate the
improved methodology, we applied it to Burkina
Faso and revealed that nutrient depletion is
occurring throughout the country at rates
of 20 15 kg N ha-1
, 3:7 2:9 kg P ha-1 and
15 12 kg K ha-1
. The resulting spatial soil
nutrient balances at the national level can constitute the basis for targeting soil fertility policies at
lower levels.
Original language | English |
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Pages (from-to) | 111–131 |
Journal | Nutrient Cycling in Agroecosystems |
Volume | 78 |
DOIs | |
Publication status | Published - 23 Jan 2007 |
Externally published | Yes |