the atchafalaya river is at the mouth of the mississippi river.
the atchafalaya river is at the mouth of the mississippi river.
what is at the mouth of the mississippi river?
the atchafalaya river
fortunately, a variety of paleoclimate and paleohydrologic proxies,which can be used to reconstruct the prehistoric discharge of the mississippi river, can be found in the sediments of the louisiana continental shelf and slope, including the orca and pygmy basins, within the gulf of mexico. these proxies have been used by quaternary geologists, paleoclimatologists, and oceanographers to reconstruct both the duration and discharge the mouth of the prehistoric mississippi river for the late glacial and postglacial periods, including the time of meltwater pulse 1b. the chronology of flooding events found by the study of numerous cores on the louisiana continental shelf and slope are in agreement that the timing of meltwater pulses. for example, meltwater pulse 1a in the barbados coral record matches quite well with a group of two separate mississippi river meltwater flood events, mwf-3 (12,600 radiocarbon years ago) and mwf-4 (11,900 radiocarbon years ago). in addition, meltwater pulse 1b in the barbados coral record matches a cluster of four mississippi river superflood events, mwf-5, that occurred between 9,900 and 9,100 radiocarbon years ago. in 2003, aharon reported that flood event mwf-5 consists of four separate and distinct superfloods at 9,970-9,870; 9,740-9,660; 9,450-9,290; and 9,160-8,900 radiocarbon years ago. the discharge at the mouth of the mississippi river during three of the four superfloods of mwf-5 is estimated to have varied between 0.07 and 0.08 sverdrups (million cubic meters per second). the superflood at 9450-9290 radiocarbon years ago is estimated to have had a discharge of 0.10 sverdrups (million cubic meters per second). this research also shows that the mississippi superfloods of mwf-5 occurred during the preboreal. the same research found an absence of either meltwater floods or superfloods discharging into the gulf of mexico from the mississippi river during the preceding thousand years, which is known as the "cessation event", that corresponds with the younger dryas stadial.
meltwater pulse 1b
conservation of the mississippi river watershed has become an important issue that many organizations are undertaking because the capacity of the river to remove nutrients from the water is decreasing and the surrounding ecosystems are being diminished. the mississippi river basin encompasses 31 u.s. states with an area of 1,837,000 square miles. the mississippi river's capacity to remove nutrients has diminished due to a range of human activities, such as development, taking place along the mississippi river itself and the streams and tributaries linked to it. the layouts of the river, the floodplains, and the watershed have also been modified using engineering techniques for acres of agriculture fields and urban expansion. with increase of natural prairie land being converted to land for agricultural and urban use, there has been an excess of nutrients that are discharged into the mississippi river and its adjoining streams. nitrates and phosphorus are the two main contaminants that pollute the mississippi river watershed. this nutrient pollution comes from a surplus of phosphorus and nitrogen, both of which occur naturally in water and air. in the upper mississippi river basin farmland, nitrate fertilizer has been overused in farming, with the high demand for corn as a contributing factor. corn, which is used to make ethanol for biofuel, has become the number one crop in the farmland that drains into the mississippi river. soybeans are another crop in the upper mississippi river basin farmland that drain into the watershed, and nitrates are the main fertilizer used on soybeans and corn.
mississippi river watershed conservation programs