Báo cáo nghiên cứu khoa học " IMPROVING CAPABILITY FOR ASSESSING SOIL CONSTRAINTS USING THE SCAMP DECISION SUPPORT SYSTEM " docx

Collaboration for Agriculture and Rural Development
(CARD)
Program
204
IMPROVI
NG CAPABILITY FOR ASSESSING SOIL CONSTRAINTS USING
THE SCAMP DECISION SUPPORT SYSTEM
Project title:
Improving capability of provincial extensionists for assessing soil constraints
to sustainable production through the use of the SCAMP decision support
s
ystem
Project code
: CARD 009/06 VIE
Author(s):
Dr. Phan Thi Cong
1
; Dr. Philip W Moody
2
Project implementing organizations:
1
Institute of Agricultural Sciences of Southern Vietnam
2
Queensland Department of Environment and Resource Management
Sydney Uni
versity
, Australia
SUMMARY
Rural poverty reduction in Vietnam will not be achieved unless the capacity of farmers to adopt
profitable and sustainable agricultural systems is enhanced through technology and knowledge
products. Vietnam has an effective nati

onal extension network, and this network is widely accepted by
farmers as a source of information and advice. However, agricultural extensionists often lack a basic
background in soil science making it difficult for farmers to obtain information on sustain
able soil
management. The result is ‘one size fits all’ advice on cropping and tillage management. Fertiliser
recommendations follow a recipe book based on the crop without regard to existing levels of soil
fertility or inherent soil characteristics. Howe
ver, the key to sustainable and profitable cropping is a
soil
-
specific approach to soil management and nutrient inputs. This CARD project addressed the
capacity gap in the soils knowledge of extensionists by providing basic training in soil and fertiliser
management.
In a previous ACIAR
-
funded project, the decision support package (‘SCAMP’
-
Soil Constraints and
Management Package) was developed to identify soil constraints from simple field observation of soil
features, supported by simple field and laborat
ory chemical analyses. SCAMP uses this soil
-
specific
assessment to develop sustainable practices for soil and nutrient management. In the CARD project,
SCAMP training courses were held for district and provincial extensionists in Gia Lai, Ninh Thuan
and T
ay Ninh Provinces. The workshops comprised in
-
field training to determine field texture, pH,
and EC of soils and to observe and record properties such as position in the landscape, drainage,

permeability, colour, structure and compaction. The implications
of these properties for soil
management were explained and discussed. At the Gia Lai and Tay Ninh workshops, participants
visited local field experiments that had been set up to demonstrate how soil constraints identified in
the SCAMP assessment could be
addressed with management practices. Benefit/cost analysis of these
practices demonstrated the benefits of using SCAMP to assess soil constraints to productivity.
In total, 167 participants were trained at the workshops and answers to questionnaires indi
cated that
over 90% of participants would apply the knowledge and concepts presented at the workshops to their
local situation by organising training workshops and one
-
on
-
one interactions with farmers. In
addition, the IAS project team provided SCAMP train
ing to project staff involved in the Agricultural
Development Projects of the non
-
government organisation World Vision Vietnam. These World Vision
CARD 009/06 VIE
–
Capacity building in soils assessment usin
g SCAMP
205
project staff then trained over 500 smallholder farmers in basic soil management, thus efficiently
extending
the SCAMP training to individual farmers.
Outputs from the project included reports that identified soil constraints to crop production in the
target areas of the Central Highlands, South Central Coast and South East Regions. Site

-
specific
management guid
elines for sustainable production of focus crops on major soil groups in these areas
were documented. In addition, the SCAMP manual has been translated into Vietnamese and is used as
resource material at the workshops.
1.
Project contents, methodology
and
results
1.1
Training Workshops
The training workshops consisted of one day
of lectures on basic soil properties, how they
are measured and what they mean. The second
day consisted of a field trip to local sites on
different soil types. Soil pits were d
ug to 150
cm depth to examine soil profile characteristics
and to discuss the soil constraints and
sustainable management using SCAMP.
Participants were then split into groups to
undertake their own SCAMP assessments at
different sites. The local demonst
ration field
experiments were also visited, and
observations made on crop growth responses
to the farmer’s practice and the SCAMP
treatments. On the last day of the workshop,
teams reported back their results and these

were discussed.
1.2
Demonstration
Field Experiments
The workshops in Gia Lai and Tay Ninh were
supported by demonstration field experiments
that compared SCAMP
-
assessed treatments
with local farmer practice. Maize was grown at
both sites. SCAMP treatments (balanced
fertilisation using fer
tiliser ‘straights’ such as
FMP and urea, and the application of locally
available plant amendments) had higher
benefit cost ratios than farmer practice (Fig. 1).
0
0.5
1
1.5
2
2.5
3
3.5
4
Farmer Practice
SCAMP
Farmer Practice
SCAMP
Ferralsol

Acrisol
Benefit/Cost
Yr 1
Yr 2
Yr 3
Figure 1.
Benefit/Cost ratios of SCAMP treatments and Farmer Practice applied to maize at
Gia Lai
(Ferralsol) and Tay Ninh (Acrisol)
Collaboration for Agriculture and Rural Development
(CARD)
Program
206
1.3
Documentation of Soil
-
specific
Management Guidelines for
Regional Soils
Based on available information on regional
soils and cropping systems, SCAMP
assessments were prepared on soil constraints
to crop prod
uction in the target areas of the
Central Highlands, South Central Coast and
South East Regions. These reports also
provided site
-
specific management guidelines
for sustainable production of focus crops on

major soil groups within the regions.
1.4
Capacit
y Building
The questionnaires at the training courses
indicated some major changes in the
perceptions of extensionists as a result of the
workshops. In particular there was increased
understanding of the impacts of key soil
properties such as field texture
on soil
management, and greater awareness of the
reasons for the beneficial effects of green
manure residues on soil productivity. In
particular, a better understanding of the effects
of specific soil properties on constraints
resulted in specific, rather
than general,
suggestions for sustainable management
practices. It was also recognised that
application of fertilisers was not the answer to
all soil productivity problems.
All participants indicated their intention to
train local farmers in sustainable
soil
management using the SCAMP framework as
the basic resource tool. It is expected that this
will lead to widespread dissemination of
knowledge. A mobile soil testing laboratory
was identified by the participants as a high

priority to improve fertilise
r management.
A very notable achievement of the Vietnamese
project staff was the close interaction with the
agricultural development projects of the NGO
World Vision, particularly in Bac Binh. The
IAS project staff ran a special SCAMP
workshop in Ho
Chi
M
inh City in 2007 for
project managers from several World Vision
agricultural development projects in Vietnam.
2
.
Recommendation
It was clearly identified by the extensionists
that there was a high priority need for a
national mobile soil
-
testing service.
This was
because fertiliser recommendations currently
follow a recipe approach based on crop type
without consideration of the existing soil
fertility status. This situation leads to over
-
application of inorganic fertilisers or
unbalanced nutrient addition
. To counteract

this, on
-
site soil analyses for nitrate,
phosphorus and potassium are required. IAS
staff have been trained to do these analyses
rapidly in the field with a minimum of
equipment. National mobile soil testing
services are funded by the natio
nal
governments in Thailand (Dr Soils Program)
and the Philippines. In these countries, rapid
soil analyses are undertaken on farmers’ soil
samples at farmer field days, and on
-
the
-
spot
fertiliser recommendations are given in
conjunction with advice on ot
her issues such as
plant disease and pest management.
It is strongly recommended that such an
approach be adopted in Vietnam as a national
agricultural initiative. SCAMP assessment of
local soils in association with a mobile lab to
undertake analyses on
farmer samples has
tremendous potential for extending sustainable
land management practices throughout the
country.

CARD 009/06 VIE
–
Capacity building in soils assessment usin
g SCAMP
207
Some pictures from a training course
Participants from the Southern Central Coast at
Phan Rang Thap Cham on 25
-
27 June 2008
Australi
an Project Leader, Dr Philip Moody
and the IAS Director, Prof. Dr Bui Chi Buu at
the training course
Dr Philip Moody and Dr Phan Thi Cong were
explaining soil constraints to crop production of
an alluvial soil where surface runoff is the main
water sup
ply mean practiced
Group discussion on soil texture, pH, EC
An Extremely compacted alluvial soil from
Phan Rang Thap Cham, Ninh Thuan where
custard apples and grapes are grown
In contrast, so easy to make a soil pit on a
sandy soil grown to onion
and garlic from Phan
Rang Thap Cham, Ninh Thuan. Participants
from each group examined the soil by
themselves.