4. Scantic-Buxton-Adams . Soils developed above the floodplain of the 

 Royal River. Adams soils develop in sand deposits and are deep, 

 excessively drained, and sandy. Adams soils are Spodosols. 



Surficial deposits and their attendant surface soils provide physical 

 substrates capable of supporting a variety of elements: forests, wildlife, 

 agriculture, and other human activities. Information on the major coastal 

 soils is available from the U.S. Department of Agriculture Extension Agents in 

 coastal counties. 



To maintain an optimum level of ecological suitability in soils, a balance 

 must be sustained between erosion and accumulation. Soils accumulate by 

 addition of material to the soil column surface or by the breakdown of parent 

 material at the column base. The latter mode of gain is extremely slow in 

 temperate latitudes. Soil gains are primarily restricted to addition of 

 organic matter as litter or decomposing vegetation in terrestrial 

 environments, organic growth and sedimentation in palustrine environments, and 

 inorganic sedimentation on alluvial floodplain soils. Rates of soil gain in 

 coastal Maine are unknown. 



Soil losses can be attributed to natural surface erosion by sheet wash, 

 streambank erosion, and slope failure. People have upset the soil balance in 

 certain areas of coastal Maine by a variety of activities. Rates of soil loss 

 are discussed in chapter 3, "Human Impacts on the Ecosystem." 



Hydrology 



The distribution, chemistry, and movements of surface waters and groundwater 



are important determinants of surficial deposits. Together these geological 



and hydrological factors influence the development of plant and animal 

 communities and affect human land use. 



Groundwater . The occurrence, movement, quality, and retrievability of 

 groundwater in the coastal zone are major driving forces of human, plant, and 

 animal population dynamics. In Maine, the abundance and availability of 

 groundwater are primarily determined by the level to which groundwater will 

 rise, the nature and distribution of unconsolidated surficial deposits, and 

 the distribution of bedrock fractures (Caswell 1977). 



Aquifers are storage deposits for groundwater. They receive water from 

 precipitation or from surface water entering the substrate at the aquifer's 

 recharge area. The major aquifers in Maine are restricted to surficial 

 deposits of coarse-textured sand and gravel and to major fracture systems. 

 Recharge areas for aquifers are coarse-grained surficial deposits of large 

 areal extent. 



Acquiring groundwater for human use, either municipal or commercial, without 

 disrupting wetland ecology requires knowledge of a region's groundwater 

 characteristics. This is necessary to prevent contamination of groundwater 

 supplies from surface waste disposal activities. Basic information about 

 groundwater in coastal Maine will be reviewed below. Regional data are 

 discussed in appendix D. 



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