Selected Publications

The application of high-frequency measurements could potentially enhance current understanding of the hydrology and biogeochemistry of artificially drained agricultural lands. In addition to intensive drainage flow measurements (every 15 min), two high-frequency sampling systems were implanted to monitor, on an hourly basis, nitrate-nitrogen concentrations [NO3-N] in the drainage outlet and at multiple points in the shallow groundwater. This paper provides a description of this novel in situ measurement system and reports example data obtained during a rainfall event. High-frequency measurements of [NO3-N] at the field edge could potentially advance understanding of agricultural drainage systems, including increased accuracy of (1) nitrate loading estimates, (2) spatiotemporal dynamics of nitrate export during rainfall events, and (3) nonlinear hydrochemical (C-Q) relationship. Combining high-frequency measurements of [NO3-N] in drainage water at the field edge and shallow groundwater within the field gives the opportunity for the next steps in identifying and quantifying key processes, mechanisms, hot moments, and active zones that control nitrate dynamics in drained agricultural land.
In jidedh, 2019

Recent Posts

As of now, Sep. 11th, 2018, Hurricane Florence (Category 4) is approaching to eastern coastal areas of United States. There are many ways to track the path of hurricanes (or typhoons) to conduct further analysis, such as flash flooding, ocean surge and property damages. In this blog, the author tries to plot the tracking of hurricanes, using both stastic and animated maps, with the help of R and related packages. Specifically, this blog is a reproducible output.

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Introduction and motivation Nutrient input to agricultural watersheds is a very popular topic among researchers, engineers and stakeholders. Researchers in United State Geographic Services (USGS) spent a considerable amount of time and efforts to generate fertilizr estimation dataset from synthetic fertilizer and manure. Based on the dataset published by USGS, the author developed an R package, ggfertilizer, to retrieve, summarize and visualize fertilizer data in contiguous U.S.A. In this post, the author is going to briefly introduce the basics of ggfertilizer and provide a smooth and clear workflow to generate a reproducible fertilizer usage map.

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What are storm hysteresis effects? Generally, in order to investigate the dynamics of stream discharge and solute concentrations (C-Q relationship) in a watershed, researchers and environmental engineers usually set up monitoring stations in the watershed outlet. As the temporal dynamics of discharge and solute concentration is an integration of complex hydrological and biochemical processes, the relationship between solute concentration and discharge, hereafter called C-Q relationship, is mostly non-linear. If we plot the concentration against discharge within one storm event in a plot, we are supposed to see a non-linear loop, instead of a linear regression curve.

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Since Jan. 2018, my brand new website is published online. The website is powered by Blogdown and Hugo-academic, and deployed by Github Pages. All the codes are open to public and available at my github repository. I build this website to achieve two goals: helping others know more about my professional achievements, and presenting my most latest output (with details) to persons of interest. Therefore, I will list my publications, including journal articles, conference presentations and proceedings, and book chapters (if any) here.

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Recent publications

. Experimental study on geotextile envelope for subsurface drainage in Yellow River Delta. In TCSAE, 2013.

Source Document

Recent and upcoming talks

Insights from intensive water quality sampling in a drained agriculutral field
Apr 11, 2018 4:30 PM
Long-term temporal variation of nitrate concentration-stream discharge (C-Q) relationship for an agrcultural watershed in Midwest USA
Apr 11, 2018 4:30 PM
Transforming denitrifying bioreactors research and application: unveiling the inside of the blackbox
Jan 29, 2018 4:30 PM

Projects

usfertilizer

An R package to summarize the estimated county level data from USGS of USA and provided a clean version using Tidyverse.

Host R markdown and shiny apps in Digital Ocean

Some R markdown files and shiny apps were hosted remotely powered by Digital Ocean.

ggfertilizer

Retrieve, Summarize and Visualize the Fertilizer Data in USA.

Soil blogs in zhihu.com (in Chinese)

Wenlong Liu also wrote, and is still writing, blogs (in Chinsese) in zhihu.com to share his research output to audience from different backgrounds.

High frequency measurements in a drained agricultural field

Enhancing the understanding of water movement and nutrient transport in a drained agricultural field using self-designed in-situ, high frequency measuring device.

Contact