Use of geomorphic, hydrologic, and nitrogen mass balance data to model ecosystem nitrate retention in tidal freshwater wetlands

Seldomridge, E.; Prestegaard, K. L.

doi:10.5194/bg-9-2661-2012

Cited by 5 publications

(2 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Using landform equation the derived morphological parameters used for obtaining geomorphological parameters which can be considered as reflect of the surface roughness [3]. Due to intercourse between stream network and landscape, geomorphological parameters are driving force for the conversion of rainfall into runoff [4,5]. The parameters are stream frequency, bifurcation ratio, elongation ratio, drainage density etc.…”

Section: Introductionmentioning

confidence: 99%

Identification of Influential Geomorphologic Parameters on Runoff Characteristics of the Thuthapuzha River Basin in Kerala, India

Chethan

Vishnu²

2022

IJECC

View full text Add to dashboard Cite

Aims: Geomorphological parameters are signature for the conversion of rainfall into runoff. The morphometric analysis using GIS gives platform for deriving the geomorphological parameter of the river basin. Due to intercourse between stream network and landscape, geomorphological parameters are driving force for the conversion of rainfall into runoff. For finding parameter which is more significant contribution to runoff, statistical analysis gives better solution. The morphological parameters of the watershed are derived and then use landform equation for getting geomorphological parameters. Derived parameters are subjected for the factor analysis using Minitab 18 software. Place and Duration of Study: Study is conducted on Thuthapuzha River basin which is tributary of Bharathapuzha River located in Kerala, India has been selected and it is conducted on Department of Soil and water Conservation Engineering, Kelappaji College of Agricultural Engineering (KCAET), Tavanur, between June 2017 and July 2018. Methodology: From seventeen Micro-watershed the geomorphological parameters are derived and subjected to factor analysis. Interpretation of factor loadings, communalities, variance, % variance, factor score gibes more influencing parameters on runoff. Results: The total percentage variance explained by all the factors is about 83.9%, which gives the analysis is a good approach. Runoff factor exhibits the highest percentage variance of about 37% among the percentage variance explained by each factor. The highest correlation coefficient is obtained between runoff factor and the length of overland flow, and the constant of channel maintenance which are more significant parameters of river basin. Total variance explained by all three factors is 11.247 where runoff factor exhibits the highest variance of 5.192. Highest factor score is obtained from length of overland flow having factor score 0.190 followed by elongation ratio, form factor having factor score of 0.165 and 0.152 respectively which can be used as independent variable in case of regression models.

show abstract

Section: Introductionmentioning

confidence: 99%

Identification of Influential Geomorphologic Parameters on Runoff Characteristics of the Thuthapuzha River Basin in Kerala, India

Chethan

Vishnu²

2022

IJECC

View full text Add to dashboard Cite

show abstract

“…Hinkle and Tesoriero () were able to predict the extent of denitrification in aquifers at the continental scale in the United States from soil water depth, water residence time, and other variables. Many of the statistical and analytical models that have been developed for predicting nitrate retention and removal in freshwater ecosystems, including streams and wetlands, have been restricted to surface water environments (Aguilera et al, ; Alexander et al, ; Fennel et al, ; Mulholland et al, ; Seldomridge & Prestegaard, ) with less emphasis on the groundwater‐surface water interface.…”

Section: Introductionmentioning

confidence: 99%

Predicting Nitrate Retention at the Groundwater‐Surface Water Interface in Sandplain Streams

Stelzer

Scott

2018

JGR Biogeosciences

View full text Add to dashboard Cite

Groundwater-surface water ecotones present opportunities for nitrate retention because changes in organic carbon availability, redox potential, and nitrate demand often occur at these locations. Although there have been many measurements of nitrate retention and denitrification at the groundwater-surface water interface, few investigators have quantitatively predicted where nitrogen transformation occurs in this zone. Our main objective was to describe and predict spatial variation in nitrate retention and removal in shallow groundwater among and within streams in the central sand plains of Wisconsin. We predicted that nitrate transformation rates would be positively related to nitrate and particulate organic carbon availability, a negative nonlinear function of dissolved oxygen availability, and would peak at intermediate rates of groundwater discharge. Five sites on four streams were chosen that spanned an order of magnitude in groundwater nitrate concentration. Nitrate retention and N 2 production were quantified by determining how nitrate and N 2 fluxes changed along nominal 55-cm groundwater flow paths. Nitrogen transformation was widespread but highly variable within the study sites. Partial least squares regression models explained a much larger amount of variation in nitrate retention and N 2 production at the local scale than at the regional scale. Dissolved oxygen availability and groundwater discharge were the most consistent predictors of nitrate retention at both scales. We conclude that nitrate retention at the groundwater-surface water interface can be predicted but that more research is necessary to determine if nitrate transformation at this ecotone can be modeled at broader scales.Plain Language Summary Nitrogen is necessary for all forms of life but can cause water quality and health problems when there is too much of it in ecosystems. Sources of nitrogen include bacteria, fertilizers, sewage treatment plants, and fossil fuels. Streams have the ability to remove a common form of nitrogen (nitrate) from surface water and associated groundwater. For this project we were interested in predicting where nitrate is removed in shallow groundwater associated with four streams in Central Wisconsin that have high amounts of nitrate. We were able to predict where nitrate removal was occurring based on variables such as the amount of oxygen in groundwater and the flow rate of groundwater. We were more successful at predicting where nitrate removal was occurring in individual streams than when all of the streams were considered together. Our results suggest that shallow groundwater associated with healthy streams are important places for nitrate removal but that too much nitrate can overwhelm the ability of streams and groundwater to process it, which can to lead to negative impacts on aquatic ecosystems and human health. STELZER AND SCOTT2824

show abstract

Saltwater Intrusion Modifies Microbial Community Structure and Decreases Denitrification in Tidal Freshwater Marshes

et al. 2018

View full text Add to dashboard Cite

Environmental changes can alter the interactions between biotic and abiotic ecosystem components in tidal wetlands and therefore impact important ecosystem functions. The objective of this study was to determine how saltwater intrusion affects wetland nutrient biogeochemistry, with a specific focus on the soil microbial communities and physicochemical parameters that control nitrate removal. Our work took place in a tidal freshwater marsh in South Carolina, USA, where a 3.5-year saltwater intrusion experiment increased porewater salinities from freshwater to oligohaline levels. We measured rates of denitrification, soil oxygen demand, and dissimilatory nitrate reduction to ammonium (DNRA) and used molecular genetic techniques to assess the abundance and community structure of soil microbes. In soils exposed to elevated salinities, rates of denitrification were reduced by about 70% due to changes in the soil physicochemical environment (higher salinity, higher carbon:nitrogen ratio) and shifts in the community composition of denitrifiers. Saltwater intrusion also affected the microbial community responsible for DNRA, increasing the abundance of genes associated with this process and shifting microbial community composition. Though rates of DNRA were below detection, the microbial community response may be a precursor to increased rates of DNRA with continued saltwater intrusion. Overall, saltwater intrusion reduces the ability of tidal freshwater marshes to convert reactive nitrogen to dinitrogen gas and therefore negatively affects their water quality functions. Continued study of the interrelationships between biotic communities, the abiotic environment, and biogeochemical transformations will lead to a better understanding of how the progressive replacement of tidal freshwater marshes with brackish analogues will affect the overall functioning of the coastal landscape.

show abstract

Use of geomorphic, hydrologic, and nitrogen mass balance data to model ecosystem nitrate retention in tidal freshwater wetlands

Cited by 5 publications

References 43 publications

Identification of Influential Geomorphologic Parameters on Runoff Characteristics of the Thuthapuzha River Basin in Kerala, India

Identification of Influential Geomorphologic Parameters on Runoff Characteristics of the Thuthapuzha River Basin in Kerala, India

Predicting Nitrate Retention at the Groundwater‐Surface Water Interface in Sandplain Streams

Saltwater Intrusion Modifies Microbial Community Structure and Decreases Denitrification in Tidal Freshwater Marshes

Contact Info

Product

Resources

About