Stream power

About: Stream power is a research topic. Over the lifetime, 1135 publications have been published within this topic receiving 51324 citations.

Spatial distribution level of land erosion disposition based on the analysis of slope on Central Lematang sub basin

Abstract: Soil erosion is a natural process that is influenced by the magnitude of rainfall intensity, land cover, slope, soil type and soil processing system. However, it is often accelerated by human activities, such as improper cultivation of agricultural land, clearing of forest land for mining activities, and changes in topographic area due to use for other purposes such as pile materials, mined pits and so on. The Central Lematang sub-basin is part of the Lematang sub basin, at the Musi River Region Unit, South Sumatra Province, in Indonesia, which has a topographic shape with varying types of slope and altitude. The critical condition of Central Lematang sub basin has been at an alarming rate, as more than 47.5% of topographic and land use changes are dominated by coal mining activities and forest encroachment by communities. The method used in predicting erosion is by USPED (Unit Stream Power Erosion and Disposition). This is because the USPED[1] method can predict not only sediment transport but also the value of peeling (detachment) and sediment deposition. From slope analysis result, it is found that the highest erosion potential value is found on slope (8-15%) and the sediment is carried on a steep slope (15-25%). Meanwhile, the high sediment deposition area is found in the waters of 5.226 tons / ha / year, the steeper area of 2.12 tons / ha / year.

The Brahmaputra River

Abstract: The Himalayan rivers deliver about one-tenth of global particulate and dissolved materials to the ocean from only about 1.6% of the global drainage area indicating very high physical and chemical erosion rates and play a dominant role in controlling the sedimentary and geochemical budgets of the global ocean and regulating the global climate. The Brahmaputra River is the most significant among the Himalayan rivers in terms of supply of sediment and dissolved materials. Its 2900-km long stretch and 636 thousand-km2 drainage area lies in very contrasting climatic and geological regions. It originates in arid and cold region of Tibet and has significant drainage in warm and heavy precipitating zones such as Mishmi Hills, Naga-Patkoi ranges and the Shillong Plateau. It has very gentle slope in Tibet to very steep slope in the Eastern Syntaxis where it has created deepest (>5000 m) gorge of the world. Both physical and chemical erosions in the basin are highly variable with lower rates in the Tibet to very high around the Eastern Syntaxis. The Eastern Syntaxis seems to be the hot spot of physical and chemical weathering and for associated CO2 consumption, which are driven by the higher stream power of the Brahmaputra in this region. Intense and focussed erosion in the Eastern Syntaxis generates about half of the total sediment delivered by the Brahmaputra to the ocean. High sediment yield from this region seems to be responsible for the higher peaks of the Namche Barwa and the Gyala Peri and the knick point in the Tsangpo upstream the Eastern Syntaxis due to isostatic rebound.

Yaw control-by-rudder type tidal stream power generation apparatus and yaw control method of the same

Abstract: A yaw control-by-rudder type tidal stream power generation apparatus includes: a nacelle used in a tidal stream power generator that converts flowing energy of a tidal stream to generate electric power, and located in the tidal stream to be rotatable about a first rotating shaft; a rotor provided at one side of the nacelle with reference to the first rotating shaft, and configured to be rotated by the flowing energy of the tidal stream; a rudder unit provided at the other side of the nacelle with reference to the first rotating shaft, and including a rudder fixed to the nacelle and a variable rudder rotatably connected to the nacelle; and a control unit configured to control the rotation of the variable rudder. When the flow direction of the tidal stream is changed, the rotation of the variable rudder is controlled by the control unit.