Third Survey of a Long Island Salt Marsh
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The aestuarial marsh, locally known as the Jones Salt Marsh, upon which our studies were made, lies at the head of the Inner Harbor at Cold Spring Harbor, Long Island, New York. A detailed belt transect of this marsh was made in i9io-ii by the senior author.' The tension zone between salt and fresh water has since been found to fluctuate in such a way that it gives sequence to some very interesting plant successions. A resurvey of the same transect made in 1922 2 indicated that fresh water vegetation had advanced while saline vegetation had retreated seaward, due to seepage of fresh water and perhaps to the excessive precipitation during the years immediately preceding the survey. The causeway thrown across the south (inner) end of the marsh in I904 for a highway has been a potent factor, seriously affecting the changes in the vegetation on the landward side of the marsh since that time, by setting up a barrier to the advance of salt water and by changing the course and amount of fresh water seepage in the southeast corner of the marsh. Probably the changes still in progress are adjustments to these artificial changes in the habitat. The partial resurvey reported herein was made by the junior author in the summer of I928 to note what further changes had taken place since I922, where succession is going on most markedly, and to check up on conclusions drawn at that time. Some careful notes made by the senior author in I927 have also been used. Old and permanent landmarks, such as a stump of Prunus serotine which was a living tree in i9io, were used to locate the boundaries of the transect. At 437S and I iooE we found an old stake of a previous survey which helped to establish the fact that our lines approximately coincided with those of former years. Not every plant in the transect was plotted on the chart. Particular attention was given to the boundaries of definite zones of vegetation to compare advances and changes with the former surveys.