10 Hydrology and Climate Impacts on Streamflow and Sediment …
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2.4 Land Use
Land use and land cover types in the Nyando Basin are diverse (Van Der Kwast and
Zomer 2002; Onyango 2003). The main land-use types are forestry and agriculture.
Forests are found on government-designated land in Timboroa, Tinderet, Londiani,
Western Mau, and parts of South Nandi. Some parts of these forests are planted with
exotic tree species (Pinus patula, Pinus radiate and Cupressus spp), which are used
for commercial purposes. The lower parts of the basin are composed of a flood-prone
lakeshore area which is mostly used for subsistence farming of maize, beans, and
sorghum, and commercial production of sugar cane and irrigated rice. The vegetation
in the basin has changed considerably from the woods of the past to the present
shrubs. The dominant land use in the highlands is for tea, both on large estates and
small-scale farms. Other crops found in these areas are maize, potatoes, pyrethrum,
wheat, and cabbage. In the last 40 years, the basin has experienced dramatic landuse changes, as the land has been converted from small-scale farming to intense
smallholder cultivation (Verchot 2008; Swallow et al. 2002; Omuto 2003; ICRAF
2000 and 2002).
3 Methodology
3.1 Data Types and Sources
Data used in this study were gathered from both primary and secondary sources.
These include unpublished reports of the National Environment Management
Authority (NEMA), Directorate of Water Development (DWD), Water Resource
Management Authority (WRMA), and LVEMP. Reports from other NGOs and the
private sector also provide valuable information on land-use activity in the basin.
The main data used in this study are rainfall, river discharge, suspended sediment
concentrations, sediment loads, and land-use change. These data were obtained from
the Water Resources Management Authority (WRMA) and Kenya Meteorological
Department (KMD).
3.2 Secondary Data
Data on daily river discharges and Total Suspended Sediment Concentrations
(TSSCs) for the periods between 2000 and 2015 were collected at River Gauging
Station (RGS) 1GD07 (Nyando: Long. 35 10‘E and Lat. 0 10‘S) and RGS 1GD04
(Ainomotua: Long. 335 02‘E and Lat. 0 07‘S). River discharge data were obtained
from the WRMA Regional Offices in Kisumu. These two river gauging stations were
considered suitable for this study because the area upstream of the basin is the most
223
2.4 Land Use
Land use and land cover types in the Nyando Basin are diverse (Van Der Kwast and
Zomer 2002; Onyango 2003). The main land-use types are forestry and agriculture.
Forests are found on government-designated land in Timboroa, Tinderet, Londiani,
Western Mau, and parts of South Nandi. Some parts of these forests are planted with
exotic tree species (Pinus patula, Pinus radiate and Cupressus spp), which are used
for commercial purposes. The lower parts of the basin are composed of a flood-prone
lakeshore area which is mostly used for subsistence farming of maize, beans, and
sorghum, and commercial production of sugar cane and irrigated rice. The vegetation
in the basin has changed considerably from the woods of the past to the present
shrubs. The dominant land use in the highlands is for tea, both on large estates and
small-scale farms. Other crops found in these areas are maize, potatoes, pyrethrum,
wheat, and cabbage. In the last 40 years, the basin has experienced dramatic landuse changes, as the land has been converted from small-scale farming to intense
smallholder cultivation (Verchot 2008; Swallow et al. 2002; Omuto 2003; ICRAF
2000 and 2002).
3 Methodology
3.1 Data Types and Sources
Data used in this study were gathered from both primary and secondary sources.
These include unpublished reports of the National Environment Management
Authority (NEMA), Directorate of Water Development (DWD), Water Resource
Management Authority (WRMA), and LVEMP. Reports from other NGOs and the
private sector also provide valuable information on land-use activity in the basin.
The main data used in this study are rainfall, river discharge, suspended sediment
concentrations, sediment loads, and land-use change. These data were obtained from
the Water Resources Management Authority (WRMA) and Kenya Meteorological
Department (KMD).
3.2 Secondary Data
Data on daily river discharges and Total Suspended Sediment Concentrations
(TSSCs) for the periods between 2000 and 2015 were collected at River Gauging
Station (RGS) 1GD07 (Nyando: Long. 35 10‘E and Lat. 0 10‘S) and RGS 1GD04
(Ainomotua: Long. 335 02‘E and Lat. 0 07‘S). River discharge data were obtained
from the WRMA Regional Offices in Kisumu. These two river gauging stations were
considered suitable for this study because the area upstream of the basin is the most