Mokhtar Jaafar

Assessing the Impact of Fodder Maize Cultivation on Soil Erosion in the UK

The short-term gross and net soil erosion in a bare maize stubble field during a period of heavy rainfall in the winter of 2004–2005 was estimated using 7Be measurements, with the longer-term erosion rate, estimated using Cs-137 measurements and compared with the longer-term soil erosion rate for the field, estimated using 137Cs measurements. The results show that the gross and net soil erosion occurring in the field under maize stubble were considerably greater than the longer-term gross and net soil erosion rates for the field. Both sets of measurements demonstrate that the field is characterized by a high sediment delivery ratio, emphasizing that a large proportion of the sediment mobilised by erosion was transported beyond the field and towards the stream network. Depending on the weather conditions, late harvesting, the associated compaction of the soil by heavy machinery and leaving the stubble field bare over the ensuing winter can result in a substantial increase in erosion relative to the longer-term erosion rate under more traditional land use. The need to implement measures to reduce soil erosion associated with maize cultivation in England, such as the Code of Good Agricultural Practice and the Agri-Environment Schemes is clearly demonstrated.

Changes of Coastline: A Study Case of Carey Island-Morib Coast, Selangor, Malaysia

Coastal area is one of the very dynamic landscapes where erosion and deposition processes always occur. Therefore, a study has been conducted to detect the changes of coastline caused by both processes at Carey Island-Morib coast. Geospatial technology that involved the use of GIS and satellite imagery had been applied in this study. Data sources are topography map of 1974 and SPOT image of 2008. The results show that coastal erosion process was dominant in Carey Island, while deposition process was the case for Morib coast. The average value of eroded distance is higher than the average value of deposited distance which is 170 and 157 m, respectively. Coastal erosion process in Carey Island could be related to the movement of big ships along Malacca Strait and Port Klang that is capable of producing big waves and eroding energy. Meanwhile deposition process in Morib coast could be related to the transfer of land sediment to the estuary and along the coast by low-energy wave. These findings should be supported with fieldwork study that could verify the effectiveness of coastal geomorphologic agents and the impact of human activities on land in influencing the changes of coastline in Carey Island-Morib coast.