scholarly journals Drought-trigger ground-water levels and analysis of historical water-level trends in Chester County, Pennsylvania

1996 ◽  
1958 ◽  
Vol 50 (3) ◽  
pp. 243-252 ◽  
Author(s):  
H. H. Nicholson ◽  
D. H. Firth

An account is given of a field experiment in the control of ground water-level in a Fen peat soil, together with its results on the yields of crops in a six-course rotation.The seasonal variations in rainfall are presented in terms of potential evaporation and soil moisture deficit. The effect of the water-level on the moistness of the soil above it is indicated. Even in a wet summer, drying was perceptible within 18–20 in. of the ground water-level between successive falls of rain.The fluctuations of the ground water-levels are discussed. Those of the high water-levels were chiefly due to individual incidences of rain causing rises short in duration, but sufficient in the case of water-levels within 20 in. of the surface to cause total waterlogging and surface ponding. Those of the deep water-levels were most influenced by evaporation, with steady and persistent falls during any rain-free period.The deterioration of the physical condition of the soil over high water-levels is shown in the result of sieving tests. In 6 years the loss of tilth over waterlevels within 20 in. of the surface was very marked and was discernible over those as low as 30 in.The possibilities of effectively using high ground water-levels occasionally in soils in good condition are shown by the results with celery and potatoes.


1957 ◽  
Vol 47 (4) ◽  
pp. 387-396
Author(s):  
C. P. Zones

abstract The earthquake of December 16, 1954, affected hydrologic conditions in the Dixie Valley and Fairview Valley areas, Nevada. In Dixie Valley the rate of flow of water from wells was temporarily increased and water flowed for more than a month from several wells that had not flowed before. Water levels in wells were higher after the earthquake, but the trend of water levels since the earthquake has varied locally. There is no evidence that ground-water temperatures were affected. The flow of Mud Springs, which is on the main fault on the west side of Dixie Valley, increased substantially immediately after the earthquake, but since has decreased to essentially its pre-earthquake rate. The water level in Fairview Valley was about 4 feet higher after the earthquake. In East Gate Valley and at West Gate, ground-water levels were lower after the earthquake. In June, 1956, the water level in East Gate Valley was 34 feet lower than the pre-earthquake level. At West Gate the water level was about 9 feet lower. In Stingaree Valley the water level began to rise after an initial decline and reached a peak about 11 feet higher than the pre-earthquake level. Possible causes for the rise in ground-water levels in Dixie and Fairview Valleys include tilting of the confined and semiconfined aquifers in the valleys, compaction of the sediments of the valley fill, and increased upward leakage of ground water. It is possible that opening of new fractures and widening of pre-existing fractures in the bedrock between East Gate, Cowkick, and Stingaree valleys has accelerated the rate of movement of ground water between those valleys. The temporary increase in the flow of water from Mud Springs may be due to the opening of fractures in the fault zone along which the water is rising, or to a possible lowering of the land surface at the springs with a resulting increase in artesian head at the spring orifices. It is thought that any increase in the total discharge of ground water in the Dixie Valley and Fairview Valley areas is temporary because the increased discharge is probably from ground-water storage.


1998 ◽  
Vol 49 (1) ◽  
pp. 72-85 ◽  
Author(s):  
Torbjörn E. Törnqvist ◽  
Mark H.M. van Ree ◽  
Ron van 't Veer ◽  
Bas van Geel

Sea-level research in several submerging coastal regions has traditionally been based on 14C dating of basal peats that overlie a compaction-free substratum and can be related to paleo-(ground)water levels. Provided that an unequivocal relationship between (ground)water level and sea level can be assumed, this approach contains two sources of uncertainty: (1) the paleoenvironmental interpretation of samples is usually based on inherently inaccurate macroscopic descriptions in the field, and (2) 14C ages of bulk peat samples may be erroneous as a result of contamination. Due to the uncertainties in both the altitude and the age—the two crucial sources of evidence necessary to arrive at accurate sea-level curves—sea-level index points are therefore represented by considerable, but typically not quantified, error boxes. Accelerator mass spectrometry (AMS) opens new perspectives for this type of sea-level research, as illustrated by a paleoecological and AMS 14C study of basal peats from a small study area in the Rhine–Meuse Delta (The Netherlands), where previous (conventional) work revealed highly problematic results. A detailed macrofossil analysis has two purposes: (1) an inferred paleoecological succession indicates a relatively accurate level of paludification of the site, and hence rise of the (ground)water level; (2) suitable macrofossils from that specific level are then selected for AMS 14C dating. In spite of very small sample sizes, our results are consistent and indicate that this approach can constitute a step forward in high-resolution reconstruction of sea-level rise. The new results further enable a revision of Holocene (ground)water gradient lines for the Rhine–Meuse Delta. A knickpoint in these gradient lines can be related to the effect of faulting. This approach therefore also has considerable potential to unravel and quantify neotectonic activity in submerging coastal settings.


1953 ◽  
Vol 43 (1) ◽  
pp. 95-104 ◽  
Author(s):  
H. H. Nicholson ◽  
D. H. Firth

1. Observations made on growing a series of crops in rotation over a range of static ground water-levels in a Fen peat soil are recorded.2. The crops used show differences in their reaction to ground water conditions, and the seasonal incidence of rain has an overriding influence on their performance.3. The effects of ground water-level may operate directly on the growth and development of a crop or may influence it indirectly through factors such as weed infestation, difficulties of cultivation, or the incidence of disease.


1951 ◽  
Vol 41 (3) ◽  
pp. 191-202 ◽  
Author(s):  
A. Eden ◽  
G. Alderman ◽  
C. J. L. Baker ◽  
H. H. Nicholson ◽  
D. H. Firth

1. Studies were made of the effects of varying ground water-levels upon the productivity and composition of Italian Ryegrass grown on a calcareous light peat in the Fenland area. Six cuts were taken throughout the season at 3 to 4-weekly intervals.2. High ground water-level (approximately 15in. below ground surface) had a very deleterious effect on the total yield of fresh grass and of dry matter. Yields were little more than half of those obtained at medium and low water-levels (24 and 38 in. below ground surface, respectively).3. High water-level apparently interfered with nitrogen metabolism in the soil, and considerably lower percentages of crude protein were found in the grass growing on the high water-level plots than at the other levels. On the other hand, the percentage of crude fibre remained fairly constant for all levels of ground water.4. High water-level also had a depressing effect on the percentage of potassium, magnesium and chlorine in the grass. It had no obvious effect upon the calcium and phosphorus levels in the plants. The silica content of the grass rose steadily as the season advanced, this being most marked on the high water-level plots.5. Physical examination of typical plants showed the effect of the various ground water-levels upon the development of the root systems, with consequent effect upon the chemical composition of the grass.6. The composition of hay and aftermath showed similar changes to those reported for the green herbage.7. The findings are discussed in relation to grassdrying policies in Fenland areas.


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