conference magazine - Caribbean Environmental Health Institute

34
sub-watershed, and stakeholders’ engagement by means of
interviews and workshops. Specifically, the paper will address
the following components of the Plan:
A
B
S
T
R
A
C
T
S
• The Institutional Framework for Water Resources and Watershed
Management in Guyana;
• Current watershed conditions;
• Watershed improvement goals and objectives;
• Strategies, actions and priority areas to improve conditions
in the watershed and;
• A Watershed Management System.
The paper will conclude with recommendations for creating the
enabling framework to guarantee successful implementation of
the Watershed Management Plan.
Quantitative Assessment of the Impact of Landuse on the
Biophysical Characteristics of Demerara Sub-Watershed in
Guyana by Jacob Opadeyi and Paulette Bynoe
Land degradation in Guyana has been increasingly occurring
and the potential exists for it to expand. Change in land use
has been due to a rapid upsurge in economic activities over the
last ten years, in particular the sectors of forestry, mining, agriculture
with the expansion in state land leases for agriculture
and commercial activities. Guyana’s principal vulnerabilities
stem from the low-lying nature of its populated seacoast which
makes it vulnerable to flooding from sea level rise, intense precipitation
and breaches of the sea defences.
This paper provides an assessment of the Demerara Subwatershed
with specific reference to the physical and ecological
setting of the watershed and the effects of land use practices
and other human influences over time. The assessment of the
Demerara sub-watershed and its basins was undertaken using
the SWAT (Soil and Water Assessment Tool) model developed
by the Agricultural Research Service and the Texas Agricultural
Experiment Station, in Temple, Texas. In particular, the
AVSWAT-2000 an ArcView extension with a graphical user
interface for the SWAT was used. SWAT is a river basin, or
watershed, scale model developed to predict the impact of land
management practices on water, sediment, and agricultural
chemical yields in large, complex watersheds with varying soils,
land use, and management conditions over long periods. The
model is physically based and computationally efficient, uses
readily available inputs, and enables users to study long-term
impacts.
The following parameters for the sub-watershed were quantified:
Water Percolation, Water Yield, Sediment Yield, Sediment
Flow, Organic Nitrogen, Organic Phosphorus, and Nitrate Flow.
The assessment of the water quantity and water quality of Demerara
sub-watershed has produced some very interesting results
as detailed in the paper. Whereas the majority of the watershed
has very little human interaction, the significant sediment
flow in some of the watershed should be of concern.
The results of this assessment were used to develop a Watershed
Management Plan for the Demerara sub watershed, management
goals, targets and action plans.
An investigation into the feasibility of using SWAT at the subbasin
level for simulating hydrologic conditions in Jamaica by
Johanna Richards and Chandra A. Madramootoo
The Soil and Water Assessment Tool (ArcSWAT 2005) was used in
order to simulate the hydrological characteristics of the Rio-Nuevo
sub-basin, located in the parish of St. Mary, Jamaica. Historical climatic
data (precipitation and temperature) were obtained for the
watershed, while streamflow data were obtained from the Rio
Nuevo, which drains the watershed. The model was calibrated over
the period 2002-2004, and validated from the period 2005-2007.
Nash-Sutcliffe Efficiency (NSE) coefficients of performance of 0.8
and 0.5 were obtained for calibration and validation respectively for
streamflow. It has been determined that SWAT can effectively be
used to simulate surface water hydrology in this region, and there is
much potential for further use of SWAT for both surface water and
water quality modelling throughout the rest of Jamaica. This paper
outlines the development of SWAT for the Rio Nuevo watershed,
and describes the potential for use in the wider Jamaican context for
use in Integrated Water Resources Management (IWRM).
The Development of the SPI and NDVI for 3 study sites in Jamaica,
with an investigation into their use in understanding soil
water during water stressed conditions in Jamaica by Johanna
Richards, Chandra A. Madramootoo, Adrian Trotman
Agricultural production is an important contributor to the Jamaican
economy. However, drought is a serious issue in Jamaica, with the
potential to cause millions of dollars in crop losses. In fact, there
were crop losses amounting to 6 million USD in the 1999/2000
drought. Therefore, drought index information is essential to the
better planning for drought impacts and will allow for the introduction
of mitigation measures by the agricultural sector. The objective of
this paper is therefore to describe the suitability of both the Standardized
Precipitation Index (SPI), as well as the Normalized Difference
Vegetative Index (NDVI), in reflecting water stressed conditions
for three agricultural areas in Jamaica. The SPI was developed for
different time scales, and then correlated to monthly soil water. Depending
on location, either the 1 or 3 month SPI was found to be
more representative of soil water conditions. The NDVI however,
does not provide a suitable representation of soil water for any of the
areas studied. As such, this paper provides soil water values for
different categories/values of the SPI, for use in future drought management
within the island.
Sustainable freshwater management and public perception: The
case of Barbados by Kwame Emmanuel
Barbados is a small, densely populated, upper-middle income country
characterized as ‘absolute water scarce’. Mismanagement of the
low freshwater availability has implications for the sustainable development
of the country. Globally, water shortage crises are primarily
influenced by social factors such as bad policies and poor govern-
FIFTH BIENNIAL CARIBBEAN ENVIRONMENTAL FORUM AND EXHIBITION