Chemistry Reference
In-Depth Information
Table 1
Changes in tropical soil fertility management paradigms over the past 5 decades and the specific role of fertiliser and
organic inputs in the context of these paradigms.
Period
Paradigm
Role of fertiliser
Role of organic inputs
Experiences
1960s and 1970s
External Input Paradigm
'First Paradigm'
Use of fertiliser alone
will improve and
sustain yields.
Organic resources play a
minimal role.
Limited success due to shortfalls in
infrastructure, policy, farming
systems, etc.
1980s
Organic Input Paradigm
Fertiliser plays a
minimal role.
Organic resources are the
main source of
nutrients.
Limited adoption; organic matter
production requires excessive land
and labour.
1990s
Sanchez' 'Second
Paradigm'
Fertiliser use is essential
to alleviate the main
nutrient constraints.
Organic resources are the
entry point; these serve
other functions besides
nutrient release.
Difficulties to access organic resources
hampered adoption (e.g. improved
fallows).
2000s
Integrated Soil Fertility
Management
Fertiliser is a major
entry point to increase
yields and supply
needed organic
resources.
Access to organic
resources has various
social and economic
dimensions.
On-going; several success stories.
