AGRICULTURE AND ENVIRONMENT - Science for Agriculture and Rural Development in Low-income Countries - page 71

In agricultural systems, typically, decisions and activities at the lower scales
interact with and affect the biophysical environment (Figure 1). Policies at higher
scales aim at creating incentives for lower-scale decision makers to achieve policy
goals such as food security, sustainable production, and/or a reduction of greenhouse
gas emissions. In agricultural systems, the decision making unit is in most cases the
farm household. This is the pivoting point for these systems: here decisions on
consumption and production are made that affect the biophysical environment. It is
the institution where the socio-economic domain and the biophysical domain interact.
Decisions at household scale also affect higher scales for example revenues from
agriculture will feedback into the regional economy or reductions in greenhouse gas
emissions at field and farm level contribute to the mitigation of global climate
change.
As in the socio-economic environment, the scales in the biophysical environment
are nested, i.e., lower-scale processes and higher-scale processes are interlinked.
Soil and land degradation, starting at the field level can lead to the destruction of
entire landscapes, and greenhouse gas emissions related to agricultural activities such
as fertilizer application and tillage contribute to global warming. In turn, higher-
scale effects, such as changes in temperature and precipitation regime, have an impact
on options for agriculture at the lower scales. Often, the higher-scale effects draw
attention (signaling) from governmental and non-governmental organizations and
lead to action (Figure 1).
Sustainable agriculture will need to take into account both, the socio-economic
and biophysical environment, acknowledging scale and process linkages.
How to operationalize the sustainability concept for agriculture is not clear. Econo-
mic development does not automatically lead to cleaner products and production
processes and policies are needed to promote (or maybe enforce) the transition to

Socio-economic environment Socio-economic environment Biophysical environment Biophysical environment

trends trends

global global global global

regional regional

eco-region eco-region

Signaling Signaling

national national

watershed watershed

province province

landscape landscape

village village

plot plot

farm household farm household

Interaction Interaction

variability variability

individual individual point point

Figure 1. Man-environment interactions (after Dietz et al. 2004)