D.M. Amatya

D.M. Amatya
US Forest Service | FS · Center for Forested Wetlands Research

PhD. PE

About

223
Publications
62,619
Reads
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4,866
Citations
Citations since 2016
50 Research Items
2269 Citations
20162017201820192020202120220100200300
20162017201820192020202120220100200300
20162017201820192020202120220100200300
20162017201820192020202120220100200300
Additional affiliations
August 2002 - present
US Forest Service
Position
  • Research Hydrologist
Education
August 1988 - July 1993
North Carolina State University
Field of study
  • Biological & Agricultural Engineering (Soil and Water)
June 1983 - August 1985
Duke University
Field of study
  • Civil & Environmental Engineering (Hydrology & Water Resources)

Publications

Publications (223)
Article
The goal of this study is to develop geospatial-hydrology models incorporating design rainfall intensities and land morphologic features to identify erosion hazards and vulnerability risks to road culverts/stream crossings in three watersheds at USDA Forest Service long-term experimental forests: i) Coweeta Hydrologic Laboratory, NC, ii) Santee Exp...
Article
The forest landscape of the Southeastern Atlantic coastal plain of the USA is experiencing increased threats from extreme precipitation events, tropical storms, flooding, droughts, and growing urbanization impacting on vegetation, road infrastructure, water extraction, and other related ecosystem processes (e.g. storm runoff, nutrient and carbon cy...
Article
In this study, we calibrated and tested the Soil Conservation Service Curve Number (SCS-CN) based Modified Sahu-Mishra-Eldo (MSME) model for predicting storm event direct runoff (Qtot) and its soil saturation coefficient α as a threshold antecedent moisture condition for partitioning into overland surface and shallow subsurface runoff components. T...
Conference Paper
Full-text available
In this study, we calibrated and tested the Soil Conservation Service Curve Number 21 (SCS-CN) based Modified Sahu-Mishra-Eldo (MSME) model for predicting storm event total direct 22 runoff (Qtot) The MSME model satisfactorily predicted the estimated Qtot_pred for three watersheds, 23 unsatisfactory for one watershed. These results demonstrate MSME...
Article
Full-text available
The objective of this study was to test pre-treatment hydrologic calibration relationships between paired headwater watersheds (WS77 (treatment) and WS80 (control)) and explain the difference in flow, compared to earlier published data, using daily rainfall, runoff, and a water table measured during 2011–2019 in the Santee Experimental Forest in co...
Article
Full-text available
In the present study, we examined the relationships between (1) N, P, total organic carbon (TOC), and total suspended sediment (TSS) each and stream flow and water table elevation, individually (2) N, P, and TOC, each and TSS, and (3) stream water C/N ratios and stream flow in managed pine forests with various switchgrass treatments implemented on...
Article
Full-text available
The objectives of this study were (1) to test the hypothesis that fertilizer applications do not increase nutrient fluxes on a switchgrass/pine forest (IC) when compared to a mature pine forest (MP) and (2) to evaluate post-fertilization (post-fert, 2014–2016) fluxes of nitrogen (N) and phosphorus (P) on IC and compare them to those observed during...
Article
Long-term research on gauged watersheds within the USDA Forest Service’s Experimental Forest and Range (EFR) network has contributed substantially to our understanding of relationships among forests, water, and hydrologic processes and watershed management, yet there is only limited information from coastal forests. This article summarizes key find...
Article
Highlights Proposed new method to assess subsurface and surface runoff from drained forested watershed. Factor F p in the graphical peak discharge method is less in forested wetland watershed than recommended by USDA. Modified graphical peak discharge method correctly approximated observed peak discharges. Abstract. The NRCS curve number (CN) metho...
Article
Full-text available
Study region: Southeastern United States Study focus: The objective was to evaluate the ability of two modified SCS-CN models to predict direct runoff (DRO) and peak discharge rate (Q p) for selected storm events in three forested watersheds in the region-one low-gradient system in South Carolina, two high-gradient upland systems in North Carolina,...
Article
Full-text available
Wetland silviculture on the Southeastern Coastal Plain attempts to balance competing objectives of draining topsoils sufficiently to provide access and promote tree growth while maintaining hydric soil characteristics in compliance with the Clean Water Act. This balancing act is dynamic as soil hydraulic properties, and thus water table regimes, ch...
Article
Intercropping switchgrass (Panicum virgatum) with pine can increase bioenergy feedstock production without land opportunity costs but can potentially alter water budgets. Measuring evapotranspiration (ET) and its parameters (stomatal conductance (gs), leaf area index (LAI), canopy temperature (Tc), and soil moisture (SM)) across cropping systems is...
Chapter
Full-text available
Tidally influenced coastal forested wetlands can be divided into two broad categories, mangroves and freshwater forested wetlands. These forested wetlands perform valuable ecosystem services, and both are endangered by threats of sea level rise and land use. Understanding the mechanisms that control the distribution of tidal forests has been greatl...
Article
Full-text available
Sustainable management of forested wetlands requires an understanding of water Table (WT) dynamics affected by rainfall and evapotranspiration (ET) and management practices, designed to sustain water quality, quantity, and ecosystem functions and productivity. In this paper analysis of long-term data from four drained and six undrained sites on coa...
Article
Full-text available
Forest harvesting and management techniques were hypothesized to result in significant differences in stream water N (NO-N), P (total P [TP]), and total suspended sediment (TSS) responses among regions of United States. The objectives were (i) to determine the mean response periods after harvesting for each water quality variable, (ii) to compare t...
Article
Managing water resource systems usually involves conflicts. Water recognizes no borders, defining the global geopolitics of water conflicts, cooperation, negotiations, management, and resource development. Negotiations to develop mechanisms for two or more states to share an international watercourse involve complex networks of natural, social and...
Article
This article compares the short-term and long-term hydrology of two typical forests in the humid Atlantic Coastal Plain, including a relatively undisturbed forest with natural drainage in South Carolina (SC) and a drained pine plantation in North Carolina (NC), using monitoring and modeling approaches. Highly dynamic outflow (O) from both of these...
Article
Given South Carolina's ongoing water planning efforts, in this study, we evaluated seasonal and annual potential evapotranspiration (PET) using measured Class A pan evaporation (PE) and 3 widely used estimation methods for the state with 3 distinct physiographic regions (Coastal, Piedmont, and Mountain). The methods were temperature-based Hargreave...
Article
Full-text available
The study goal was to develop automated user-friendly remote-sensing based evapotranspiration (ET) estimation tools: (i) artificial neural network (ANN) based models, (ii) ArcGIS-based automated geospatial model, and (iii) executable software to predict pine forest daily ET flux on a pixel- or plot average-scale. Study site has had long-term eddy-f...
Article
Full-text available
The objective of this paper is to present a relatively simplified model to predict daily water table (WT) by solving ordinary differential equation dWT (t)/dt = F (α1, α2, α3, WT0(t), RF (t), PET (t)), with α1, α2, α3, WT0 as parameters, and RF (rainfall) and PET (potential evapotranspiration), respectively, as inputs. The model was calibrated and...
Technical Report
Full-text available
Growing switchgrass (Panicum virgatum L.) as an intercrop in managed loblolly pine (Pinus taeda L.) plantations has emerged as a potential source of bioenergy feedstock. Utilizing land resources between pine trees to produce an energy crop can potentially reduce the demand for land resources used to produce food; however, converting conventionally...
Article
Full-text available
Effects of cypress knee roughness on flow resistance and discharge estimates of the Turkey Creek watershed. In this study effects of cypress knees as vegetation resistance factor on Turkey Creek watershed discharge calculation were analyzed. The Turkey Creek watershed is a 3rd order stream system draining an approximate area of 5,240 ha. It is loca...
Article
Historically, paired watershed studies have been used to quantify the hydrological effects of land use and management practices by concurrently monitoring two similar watersheds during calibration (pre-treatment) and post-treatment periods. This study characterizes seasonal water table and flow response to rainfall during the calibration period and...
Article
Full-text available
Forests are receiving more attention for the ecosystem goods and services they provide and the potential change agents that may affect forest health and productivity. Highlighting case examples from coastal forests in South Carolina, USA, we describe groundwater processes with respect to stressors and potential responses of a wetland-rich forested...
Article
Historically, paired watershed studies have been used to quantify the hydrological effects of land use and management practices by concurrently monitoring 2 similar watersheds during calibration (pretreatment) and post‐treatment periods. This study characterizes seasonal water table and flow response to rainfall during the calibration period and te...
Article
Full-text available
Interplanting a cellulosic bioenergy crop (switchgrass, Panicum virgatum L.) between loblolly pine (Pinus taeda L.) rows could potentially provide a sustainable source of bio-feedstock without competing for land currently in food production. The objectives of this study were to: (1) quantify the concentrations and loads of drainage water nitrogen (...
Article
Full-text available
The extreme precipitation event on October 3-4, 2015, likely resulting from the convergence of a persistent deep easterly flow, the continuous supply of moisture, the terrain, and the circulation associated with Hurricane Joaquin off the eastern Atlantic Coast (http://cms.met.psu.edu/sref/severe/2015/04Oct2015.pdf) resulted in extreme and prolonged...
Article
Full-text available
Remote sensing has increasingly been used to estimate evapotranspiration (ET) and its supporting parameters in a rapid, accurate, and cost-effective manner. The goal of this study was to develop remote sensing-based models for estimating ET and the biophysical parameters canopy conductance (g c), upper-canopy temperature, and soil moisture for a ma...
Poster
We have used a set of metrics for storm runoff events (rainfall, runoff, runoff-rainfall ratio, duration of runoff event, peak flow rate, baseflow, initial water table depth, and initial flow rate) to characterize stream flow behavior of a minimally disturbed forested watershed (Turkey Creek) that can serve as a reference of a pre-development scena...
Article
The extreme precipitation event on October 3-4, 2015, likely resulting from the convergence of a persistent deep easterly flow, the continuous supply of moisture, the terrain, and the circulation associated with Hurricane Joaquin off the eastern Atlantic Coast (http://cms.met.psu. edu/sref/severe/2015/04Oct2015.pdf) resulted in extreme and prolonge...
Article
Evapotranspiration (ET) processes at the leaf to landscape scales in multiple land uses have important controls and feedbacks for local, regional, and global climate and water resource systems. Innovative methods, tools, and technologies for improved understanding and quantification of ET and crop water use are critical for adapting more effective...
Article
Full-text available
A reliable estimate of potential evapotranspiration (PET) for a forest ecosystem is critical in ecohydrologic modeling related with water supply, vegetation dynamics, and climate change and yet is a challenging task due to its complexity. Based on long-term on-site measured hydro-climatic data and predictions from earlier validated hydrologic model...
Article
Full-text available
Studies examining potential evapotranspiration (PET) for a mature forest reference compared with standard grass are limited in the current literature. Data from three long-term weather stations located within 10 km of each other in the USDA Forest Service Santee Experimental Forest (SEF) in coastal South Carolina were used to (1) evaluate monthly a...
Article
Hydrologic and water quality models are increasingly used to determine the environmental impacts of climate variability and land management. Due to differing model objectives and differences in monitored data, there are currently no universally accepted procedures for model calibration and validation in the literature. In an effort to develop accep...
Conference Paper
Full-text available
The abnormal precipitation event on October 3-4, 2015 reported to be likely contributed by a persistent deep easterly flow, the continuous supply of moisture, the terrain, and the circulation associated with Hurricane Joaquin in the eastern Atlantic Coast (http://cms.met.psu.edu/sref/severe/2015/04Oct2015.pdf) resulted in extreme and prolonged floo...
Book
Full-text available
Forest evapotranspiration: measurement and modelling at multiple scales
Article
Full-text available
Remotely sensed images including LANDSAT, SPOT, NAIP orthoimagery, and LiDAR and relevant processing tools can be used to predict plant stomatal conductance (gs), leaf area index (LAI), and canopy temperature, vegetation density, albedo, and soil moisture using vegetation indices like normalized difference vegetation index (NDVI) or soil adjusted v...
Article
Full-text available
Water yield, water supply and quality, wildlife habitat, and ecosystem productivity and services are important societal concerns for natural resource management in the 21 st century. Watershed-scale ecohydrologic studies can provide needed context for addressing complex spatial and temporal dynamics of these functions and services. This study was c...
Article
Full-text available
A study was initiated to investigate the sustainability effects of intercropping switchgrass (Panicum virgatum L.) in a loblolly pine (Pinus taeda L.) plantation. This forest-based biofuel system could possibly provide biomass from the perennial energy grass while maintaining the economics and environmental benefits of a forest managed for sawtimbe...
Article
Full-text available
Paired watershed studies have historically been used to quantify hydrologic effects of land use and management practices by concurrently monitoring two neighboring watersheds (a control and a treatment) during the calibration (pre-treatment) and post-treatment periods. This study characterizes seasonal water table and flow response to rainfall duri...
Article
Full-text available
The main objective of the paper is to estimate the influence of time of concentration (TC) on maximum flow in an urbanized watershed. The calculations of maximum flow have been carried out using the Rational method, Technical Release 55 (TR55) procedure based on NRCS (National Resources Conservation Services) guidelines, and NRCS-UH rainfall-runoff...
Article
Full-text available
Imparting knowledge of the physical processes of a system to a model and determining a set of parameter values for a hydrologic or water quality model application (i.e., parameterization) are important and difficult tasks. An exponential increase in the literature has been devoted to the use and development of these models over the years. Few artic...
Article
Evapotranspiration (ET) is a key component of the hydrologic cycle in terrestrial ecosystems and accurate description of ET processes is essential for developing reliable ecohydrological models. This study investigated the accuracy of ET prediction by the DRAINMOD-FOREST after its calibration/validation for predicting commonly measured hydrological...
Conference Paper
Full-text available
Potential evapotranspiration (PET) is a driving factor behind the estimates of ecosystem evapotranspiration (ET). Most of the PET methods with varying levels of complexity have been developed for a standard grass reference with unlimited soil moisture. There is only limited information examining the difference between the PET for a standard grass r...
Article
Global sensitivity analysis is a useful tool to understand process-based ecosystem models by identifying key parameters and processes controlling model predictions. This study reported a comprehensive global sensitivity analysis for DRAINMOD-FOREST, an integrated model for simulating water, carbon (C), and nitrogen (N) cycles and plant growth in lo...