Progress 01/01/03 to 12/31/03
Outputs
Our overall goal is to develop a hydrogeologic classification of New York fens that will help land managers determine if nutrient enrichment from agriculture or development activities reduces the plant diversity of these particularly species-rich wetlands. Specific objectives of this project are to evaluate the classification by testing two hypotheses following from it: (a) low phosphorus (P) availability rather than nitrogen (N) limits plant production and hence controls species diversity in rich fens; and (b) P limitation is a function of the control that hydrogeologic setting (HGS) exerts over rates and chemistry of ground water flow to fens, particularly flows of calcium-rich water. Through extensive surveys of nearly 50 fens, experimental fertilization of 7 fens, and an intensive network of groundwater monitoring wells in 7 sites, we have found that: (a) rich fens are either P-limited or co-limited by N and P; and (b) species density of rich fens is highly
correlated with soil nutrients and bicarbonate concentrations in groundwater. However, intensive monitoring of ground-water hydrology and water chemistry for the past two years in three fens has revealed that sulfate plays a major role in determining P availability. Intensive vegetation sampling along the ground-water flow paths in these fens showed that the turnover of species along the path is high, leading to extremely high beta diversity in these fens in addition to the very high species density (number of species per square meter). Hydrologic and geochemical variability along the flow path appear to control this aspect of diversity. Two honors theses were completed under this project in 2003 and three others were initiated.
Impacts
The results of this work are being used by conservation organizations to help guide decisions about managing nutrients in wetland watersheds, including decisions about land acquisition to protect wetlands of high biological diversity. Specifically, the project seeks to provide information on the relative importance of managing nitrogen or phosphorus in wetland watersheds by identifying the nutrients controlling plant growth in the wetlands.
Publications
- Bailey, K.M., Bedford, B.L. 2003. Transient geomorphic control of water table and hydraulic head reversals in a coastal freshwater peatland. Wetlands 23(4):969-978.
- Bedford, B.L., and K.S. Godwin. 2003. Fens of the United States: Distribution, characteristics, and scientific connection versus legal isolation. Wetlands 23:608-629.
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Progress 01/01/02 to 12/31/02
Outputs
Our overall goal is to develop a hydrogeologic classification of New York fens that will help land managers determine if nutrient enrichment from agriculture or development activities reduces the plant diversity of these particularly species-rich wetlands. Specific objectives of this project are to evaluate the classification by testing two hypotheses following from it: (a) low phosphorus (P) availability rather than nitrogen (N) limits plant production and hence controls species diversity in rich fens; and (b) P limitation is a function of the control that hydrogeologic setting (HGS) exerts over rates and chemistry of ground water flow to fens, particularly flows of calcium-rich water. Through extensive surveys of nearly 50 fens, experimental fertilization of 7 fens, and an intensive network of groundwater monitoring wells in 7 sites, we have found that: (a) rich fens are either P-limited or co-limited by N and P; and (b) species density of rich fens is highly
correlated with soil nutrients and bicarbonate concentrations in groundwater. Species richness is highest where groundwater inputs of calcium-bicarbonate are highest, probably as a function of the ability of calcium-bicarbonate to form precipitates with phosphorus, thus keeping phosphorus concentrations low. Species richness is lowest where overland flow from agricultural fields enters the fen. Two undergraduate honors theses funded under this project are nearing completion and three additional honors theses have been initiated.
Impacts
The results of this work are being used by conservation organizations to help guide decisions about managing nutrients in wetland watersheds, including decisions about land acquisition to protect wetlands of high biological diversity. Specifically, the project seeks to provide information on the relative importance of managing nitrogen or phosphorus in wetland watersheds by identifying the nutrients controlling plant growth in the wetlands.
Publications
- Drexler, J.Z. and B.L. Bedford. 2002. Pathways of nutrient loading and impacts on plant diversity of a New York peatland. Wetlands 22(2):263-281.
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Progress 01/01/01 to 12/31/01
Outputs
Our overall goal is to develop a hydrogeologic classification of New York fens that will help land managers determine if nutrient enrichment from agriculture or development activities reduces the plant diversity of these particularly species-rich wetlands. Specific objectives of this project are to evaluate the classification by testing two hypotheses following from it: (a) low phosphorus (P) availability rather than nitrogen (N) limits plant production and hence controls species diversity in rich fens; and (b) P limitation is a function of the control that hydrogeologic setting (HGS) exerts over rates and chemistry of ground water flow to fens, particularly flows of calcium-rich water. Through extensive surveys of nearly 50 fens, experimental fertilization of 7 fens, and an intensive network of groundwater monitoring wells in 7 sites, we have found that: (a) rich fens are either P-limited or co-limited by N and P; and (b) species density of rich fens is highly
correlated with soil nutrients and bicarbonate concentrations in groundwater.
Impacts
The results of this work are being used by conservation organizations to help guide decisions about managing nutrients in wetland watersheds, including decisions about land acquisition to protect wetlands of high biological diversity. Specifically, the project seeks to provide information on the relative importance of managing nitrogen or phosphorus in wetland watersheds by identifying the nutrients controlling plant growth in the wetlands.
Publications
- No publications reported this period
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