Dynamics, Degradation and Future Challenges of Wetlands in South Sumatra Province, Indonesia

This paperaims to analyzedynamics, degradation and future challenges of wetlands in South Sumatra Province, Indonesia. Research methods using Focus Group Discussion (FGD), research data and information are processedusing SPSS program. There are four dominant types of wetlands in South Sumatra, namely lebak swamps, tidal swamps, rivers, lakes, and peatlands. The area of lebakswamps has dominantly increased from year to year, while other wetlands have decreased extensively over the years. All species living in wetlands have decreased in number; the most dominant decline was experienced by fish, gymnosperm and fern and at least in moss and angiosperm. The main causes of wetlands degradation are weaken forcement and legal compliance of inadequate policies, reclamation and excessive drainage. Current efforts to protect the wetlands are restoration, groundwater control, fish population conservation and wetland reserves.

Analysis of Gravity Waves Generated at the Top of a Drainage Flow

Drainage or katabatic flows are common mesoscale circulations established as a result of differential radiative cooling of near-surface air masses in sloping terrain. The initial irruption of these flows, with sudden shifts in wind speed and direction, may result in vertical displacements of air parcels from their equilibrium position, which prove to be a common source of internal gravity waves. This paper illustrates this mechanism and describes the main features of the oscillations following the study of observational data gathered throughout one night during the Stable Atmospheric Boundary Layer Experiment in Spain 2006 (SABLES2006) field campaign. Pressure differences, measured by microbarometers set at different levels of a tower, help to interpret the evolution of other atmospheric variables, provide a detailed picture of the irruption of a drainage current, and reveal the formation of gravity waves at its top. The main parameters of the waves are derived from wavelet cross correlation of pressure time series, recorded by a surface array of microbarometers. The analysis yields, among other parameters, the horizontal component of the phase and group velocities of the gravity waves, which compare well with the velocity of irruption of the drainage current. Wavelet and other multiresolution techniques are also applied to sonic anemometer records to study the interaction between turbulence and larger-scale motions. The analysis shows evidence of heat flux divergence induced by the gravity waves, which may constitute a key factor for the vertical thermal profile in the nocturnal boundary layer (NBL) in situations of weak turbulence and important wave activity.