River Accretion Research Articles

Jamuna River Erosional Hazards, Accretion & Annual Water Discharge – A Remote Sensing & Gis Approach

Abstract. This paper presents the results of some of the Jamuna River erosional hazards from Bahadurabad Ghat to Bhuapur (near Jamuna Bridge). Results are also presented on the Jamuna River accretion and water discharge. Landsat images from 1977 to 2014 and water discharge data were analysed to find out a relationship between dynamics of erosion and accretion for different time intervals with average annual water discharge. It is clearly established that total amount of erosion and accretion rates varies with different times. The highest erosion rate 21.15 km2 year-1 was observed in the period of 1989-1992 and the highest accretion rate 13.57 km2 year-1 was observed in the period of 1980-1989. The erosion and accretion values fluctuated with increasing average annual maximum water discharge but the difference between erosion and accretion had remained low before water discharge reached to 67000 m3s-1 and it is estimated higher after crossing annual average maximum water discharge of 67000 m3s-1. This discharge value also plays an important role on bar development and active channel. It is also observed that unvegetated bar areas remained higher than active channel areas before average annual maximum water discharge reached to 67000 m3s-1. Finally, all the erosional hazards and accretion values are compared and evaluated to see their influence on the annual discharge.

Selling State Borders

Sovereign territory was bought and sold throughout much of American history, and there are good reasons to think that an interstate market for borders could help solve many contemporary economic and political problems. But no such market currently exists. Why not? And could an interstate market for sovereign territory help simplify border disputes, resolve state budget crises, respond to exogenous shocks like river accretion, and improve democratic responsiveness? Focusing on the sale of borders among American states, this Article offers constitutional, political, and ethical answers to the first question, and a qualified yes to the second.

QUANTIFYING RIVER ACCRETION IN THE UPPER RIO GRANDE GORGE, NEW MEXICO, BY USING AN ACOUSTIC DOPPLER CURRENT PROFILER

ABSTRACTThe section of the upper Rio Grande in New Mexico is important to downstream water management and the administration of water rights. It has long been believed that this remote reach of the Rio Grande is characterized by significant groundwater accretions, which contribute to water available for downstream uses. This study focused on the uppermost 30 miles of the Rio Grande in New Mexico seeking to establish locations of groundwater accretions in the reach and document magnitude of gain. In order to quantify the accretion of the upper Rio Grande, an expedition using inflatable kayaks, an acoustic Doppler current profiler (ADCP) and an electromagnetic meter was carried out in the fall of 2008 when natural surface flow was low. The study area covered a stretch of 31 miles. The expedition was able to determine that the total accretion of this stretch of the Rio Grande was 22 ft3s−1 with an average accretion rate of 0.73 ft3s−1 mile−1. Most of the reach exhibited minimal gain or loss, and most of the accretion was centred in Sunshine Valley. One of the most significant results was encountering a large artesian, subaqueous spring, which might be the largest documented spring in New Mexico and contributes nearly 50% of the accretion in the reach. The study was also able to characterize the exact locations of other significant groundwater inputs. In addition to quantifying the accretion of part of the upper Rio Grande, the study provides the framework for using advanced technology in the form of an ADCP to determine river accretions in remote locations. ADCPs offer the benefit of reducing measurement time and measurement error, collect high‐resolution data and are non‐intrusive. Overall, the use of ADCP technology to determine river accretion offers an improvement over traditional methods, and it is the hope of the authors that this technology is utilized for river accretion studies in the future. Copyright © 2011 John Wiley & Sons, Ltd.

The stratigraphy and fire history of the Kutai Peatlands, Kalimantan, Indonesia

The equatorial peatlands of the Kutai lowland of eastern Kalimantan are generally 4–10 m in thickness but some sections exceed 16 m in depth. The deposition of peat commenced about 8000 yrs ago after shallow flooding of the basin by the Mahakam River. The earliest vegetation is a Pandanus swamp which grades upwards to swamp forest dominated by dipterocarps. The peatland has expanded laterally and rivers have maintained narrow levee-channel tracks through the swamp, which has grown vertically in balance with river accretion. Historical fires are associated with extreme El Niño years of drought, but human agency is important. The fires of 1982–1983 and 1997–1998 burnt up to 85% of the vegetation on the peatland. Although charcoal analyses show that fire has occurred throughout the history of the peatland, it is rare in forests remote from rivers until the last 3000 years and only common within the last millennium. Fires are earlier and more frequent in sites accessible from waterways, and floodplains have been widely burnt down to water table or below, forming extensive lakes.

Preliminary microstructural and microchemical observations on pond and river accretion ice

Scanning electron microscopy and X-ray microanalysis were employed to investigate the morphology of impurities present in pond and river freshwater ice. Several structural features, 0.4 to roughly 1.2 mm in diameter, with distinct morphological characteristics were identified in the pond ice. The features reside both in the interior of the grains as well as at grain boundaries. In river ice, the impurity aggregates were significantly smaller than in the pond ice (the majority with sizes ⪝20 μm) with no particular shape and were concentrated in the grain boundaries.

Conjunctive Availability of Surface and Ground Water in the Albuquerque Area, New Mexico: A Modelling Approach

ABSTRACTThis study is part of an interdisciplinary analysis of the economic evaluation of the water resources of the Rio Grande region of New Mexico. It was elemental in obtaining dynamic water availabilities in time and space.The relationship of dynamic ground‐water availability and aquifer behavior under projected stresses was modeled by a ground‐water system simulator based on a mass balance of the hydrologic basin. Conditions from extreme dry to extreme wet were modeled, combined with a range of different water demands. A vast amount of information was thus obtained in the form of aquifer responses for different conditions. An analogous relationship was constructed from these data by stepwise multiple regression analysis and was of the following formλd = f (dn, L)where λd = change in water‐table elevation for the time period considered, dn= water‐table elevation at the end of the previous time period, and L = a lump factor combining surface‐water inflow and outflow, precipitation, and beneficial and nonbeneficial water uses.Other results readily obtainable from the simulation runs are river accretion or depletion curves as a function of time. These curves show the diversion effects of groundwater pumping upon the river.