Nutrients such as Nitrogen (N), Phosphorous (P) and Potassium (K) and other
micronutrients such as such as magnesium, manganese and cobalt, are
essential for the continued growth of global agricultural production. These
nutrients are typically applied to agricultural fields in the form of synthetic
fertiliser and/or manure. However, if not used efficiently, the risk of loss to water
courses and the atmosphere can increase. Inefficient use has led to global
deteriorations in water quality, algal blooms, fish kills and contributed to
greenhouse gas emissions. Poor management of nutrients is one important
reason contributing to the inefficient use of nutrients on farms. Key issues
include the over application of the wrong nutrient source to fields that do not
require it, using the wrong rate at the wrong time. Under application of nutrients
is also an issue as this has been associated with the underperformance of crops
and reductions in soil fertility levels. Farmers are advised to adopt certain
nutrient management practices that have been proven to ensure that nutrients
are targeted appropriately which has been associated with improvements in
nutrient use efficiency, production and a reduction in the risk of nutrient losses to
the environment. One such practice is called nutrient management planning.
This is a process which involves the collection of site-specific information (e.g.
stocking rate, soil fertility levels of crop type) which is then used to devise a
nutrient management plan. A nutrient management plan is a document that is
developed by farmers typically in conjunction with an agricultural advisor. This
plan makes recommendations of how best to target nutrients in line with crop
demand. However, despite widespread pressure and considerable promotion of
the advantages of nutrient management planning, uptake of nutrient
management planning by farmers remains limited globally. Policy makers are
keen to understand what motivates farmers to implement nutrient management
planning. The overall aim of the research presented in this thesis is to examine
and explain the factors which influence farmers’ intentions towards the
implementation of nutrient management planning. The two practices under
consideration are farmers’ intentions to apply fertiliser on the basis of soil test
results (practice one) and to follow a nutrient management plan (NMP) (practice
two).
A review of the literature demonstrates that there remains a dearth of studies
specifically focusing on the uptake of nutrient management planning.
Furthermore, among the existing studies, the focus is typically on explaining
uptake as a function of farm (e.g. system and farm size) and farmer
characteristics (e.g. age and education). A limited number of studies specifically
in relation to nutrient management planning focus on the socio-psychological
beliefs, including social pressure and perceptions of capability, of farmers.
Those studies that do focus on these issues typically remain qualitative in nature
and therefore generalising the results remains an issue. To accomplish the aim
of this research the well-established socio-psychological Theory of Planned
Behaviour (TPB) is used as a basis for understanding farmers’ intentions
towards implementing nutrient management planning. A number of additional
variables are also chosen based on a review of the literature such as farm
system, farm size, farmer age and education as well as use and trust in
information sources. The data came from a sample (n=1009) of Irish farmers for
the year 2016. A quota controlled system was set in place to ensure that the
sample was representative in terms of predominant farm systems and sizes in
Ireland. Ireland presents an interesting case study for analysis due to ambitious
targets to increase food production, whilst also maintaining and improving water
quality, whilst reducing overall greenhouse gas emissions from agriculture. The
issues in this Irish case are reflected more widely and therefore results from this
study can be generalised. A cross-sectional survey was designed to collect
information from farmers regarding their beliefs and intentions towards the
implementation of the aforementioned practices and information regarding the
additional variables.
To analyse the data elicited by the survey a range of econometric techniques
are applied. The primary techniques employed include binary logistic regression,
principal component analysis, latent class analysis and structural equation
modelling. In total three separate analyses are conducted which are presented
as three empirical papers. The first analyses farmers’ intentions to apply fertiliser
on the basis of soil test results whereas the second and third both focus on
farmers intentions to follow a nutrient management plan. Overall, the results
from the analyses show that subjective norm (social pressure) and perceived
behavioural control (farmers’ perception of ease/difficulty of implementation) to
implement these practices are among the most important factors determining
their intention to use them. Agricultural extension is also another key factor
influencing farmers’ intentions. However, the results from the latent class
analysis also show that the variables which influence farmers’ intentions vary
between groups in terms of significance, but also magnitude of influence
(marginal effect). Finally, results from the structural equation model also
highlight that farmers’ place their trust in different sources of information and as
trust increases farmers’ perceptions of nutrient management planning are
influenced. These results provide policy makers with useful information for
increasing the use of nutrient management planning among farmers.
The results of this thesis suggest five main strategies to increase farmers’
intentions to adopt nutrient management planning. First, increase social
pressure on farmers to use this practice. Second, increase farmers’ level of
perceived behavioural control (ability) over implementing nutrient management
planning. Thirdly, increase contact between agricultural extension and farmers,
in particular combing both one-to-one contact and group based learning
environments may be beneficial. Fourthly, information about nutrient
management planning should be targeted through the sources of information
farmers are more likely to trust. Finally, policy makers must target different
groups of farmers with campaigns designed to increase implementation of
nutrient management planning because the results show that farmers are likely
to respond differently.
Future research should be directed at examining the best methods for
increasing social pressure and perceptions of control and to encourage and
enable farmers to implement nutrient management planning and how these
campaigns should be tailored to specific groups of farmers
