Agriculture Reference
In-Depth Information
M
anagement
P
ractices (BMPs) and include: the choice of variety, planting date,
row spacing, seeding rates, integrated pest management, weed control, disease
control, and nutrient management. Focusing on the input into the field of inorganic
nutrients, BMPs are considered the management practices that foster the effective
and responsible use of fertiliser matching nutrients supply with crop requirements
and minimise their losses from the fields.
Toward a Fertiliser Precision Management
Fertiliser BMPs include the identification of the: (a) the
right product
by matching
the fertiliser characteristics to the crop site specific needs and soil properties; (b) the
right time
by synchronising the presence of the nutrient with the moment of crop
maximum demand and uptake capacity; (c) the
best rate
by matching the amount of
fertiliser input to crop needs in order to avoid over-input leading to nutrient
leaching and other losses to the environment, as well as starvation conditions;
(d) the
right place
by making sure the presence of the nutrients where plants can
efficiently take up them.
Although in a field a relatively high spatial variability in the crop requirements
of a specific nutrient could exist, fertilisers are uniformly applied, to avoid yield
gaps and considering the less fertile portion of soil, where the crops have the
maximum demand. The amounts of nutrient provided in excess with the fertiliser
can be absorbed by the crops without resulting in any benefit in term of yield or
leached towards the underground water becoming a concern for the quality of the
environment.
If spatial and temporal information about crop needs of nutrients were available
site- and time-specific inputs of the nutrient could be planned, resulting in a
precision fertilisation approach, and in a win-win option to increase fertiliser
nutrient efficiency and to improve the economic and environmental sustainability
of the crop systems. In other words, the optimisation of
dN
F
term, in the equation
defining
AE
, requires detailed information for decision support systems, allowing
farmers to adopt the minimal nutrient input for maximal return, according to a
F
ertiliser
B
est
M
anagement
P
ractices (FBMPs) approach.
Evaluating Plant Nutritional Status
Soil and Leaf Analyses
Within a field the spatial variability of the soil chemical-physical and biological
characteristics, including the amount of bioavailable forms of the mineral nutrients
essential for crops, can be pronounced. Mapping this variability and plant
