Publications by Qian Zhang

IAN is committed to producing practical, user-centered communications that foster a better understanding of science and enable readers to pursue new opportunities in research, education, and environmental problem-solving. Our publications synthesize scientific findings using effective science communication techniques.

Evaluating water-quality trends in agricultural watersheds prioritized for management-practice implementation (Page 1)

Evaluating water-quality trends in agricultural watersheds prioritized for management-practice implementation

Webber J, Chanat J, Clune J, Devereux O, Hall N, Sabo RD, Zhang Q ·
2024

Many agricultural watersheds rely on the voluntary use of management practices (MPs) to reduce nonpoint source nutrient and sediment loads; however, the water-quality effects of MPs are uncertain. We interpreted water-quality responses from as early as 1985 through 2020 in three agricultural Chesapeake Bay watersheds that were prioritized for MP implementation, namely, the Smith Creek (Virginia), Upper Chester River (Maryland), and Conewago Creek (Pennsylvania) watersheds.

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Legacy sediment as a potential source of orthophosphate: Preliminary conceptual and geochemical models for the Susquehanna River, Chesapeake Bay watershed, USA (Page 1)

Legacy sediment as a potential source of orthophosphate: Preliminary conceptual and geochemical models for the Susquehanna River, Chesapeake Bay watershed, USA

Cravotta III CA, Tasker TL, Smyntek PM, Blomquist JD, Clune JW, Zhang Q, Schmadel NM, Schmer NK ·
2024

Nutrient pollution from agriculture and urban areas plus acid mine drainage (AMD) from legacy coal mines are primary causes of water-quality impairment in the Susquehanna River, which is the predominant source of freshwater and nutrients entering the Chesapeake Bay.

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Effects of point and nonpoint source controls on total phosphorus load trends across the Chesapeake Bay watershed, USA (Page 1)

Effects of point and nonpoint source controls on total phosphorus load trends across the Chesapeake Bay watershed, USA

Zhang Q, Bostic JT, Sabo RD ·
2024

Reduction of total phosphorus (TP) loads has long been a management focus of Chesapeake Bay restoration, but riverine monitoring stations have shown mixed temporal trends. To better understand the regional patterns and drivers of TP trends across the Bay watershed, we compiled and analyzed TP load data from 90 Non-Tidal Network stations using clustering and random forest (RF) approaches.

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James Tributary Summary: A summary of trends in tidal water quality and associated factors, 1985-2021 (Page 1)

James Tributary Summary: A summary of trends in tidal water quality and associated factors, 1985-2021

Sullivan B, Gootman K, Gunnerson A, Johnson C, Mason C, Perry E, Bhatt G, Keisman J, Webber J, Harcum J, Lane M, Devereux O, Zhang Q, Murphy R, Karrh R, Butler T, Van Note V, Wei Z ·
3 November 2023

The James Tributary Summary outlines change over time for a suite of monitored tidal water quality parameters and associated potential drivers of those trends for the period 1985 – 2021 and provides a brief description of the current state of knowledge explaining these observed changes.

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Nutrient limitation of phytoplankton in three tributaries of Chesapeake Bay: Detecting responses following nutrient reductions (Page 1)

Nutrient limitation of phytoplankton in three tributaries of Chesapeake Bay: Detecting responses following nutrient reductions

Zhang Q, Fisher TR,Buchanan C, Gustafson AB, Karrh RR, Murphy RR, Testa JM, Tian R, Tango PJ ·
2022

Many coastal ecosystems suffer from eutrophication, algal blooms, and dead zones due to excessive anthropogenic inputs of nitrogen (N) and phosphorus (P). This has led to regional restoration efforts that focus on managing watershed loads of N and P. In Chesapeake Bay, the largest estuary in the United States, dual nutrient reductions of N and P have been pursued since the 1980s.

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A water quality barometer for Chesapeake Bay: Assessing spatial and temporal patterns using long-term monitoring data (Page 1)

A water quality barometer for Chesapeake Bay: Assessing spatial and temporal patterns using long-term monitoring data

Zahran AR, Zhang Q, Tango P, Smith EP ·
2022

This paper develops a barometer that indexes water quality in the Chesapeake Bay and summarizes quality over spatial regions and temporal periods. The barometer has a basis in risk assessment and hydrology, and is a function of three different metrics of water quality relative to numerical criteria: relative frequency of criterion attainment; magnitude of deviation from a numerical criterion; and duration of criterion attainment.

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Major point and nonpoint sources of nutrient pollution to surface water have declined throughout the Chesapeake Bay watershed (Page 1)

Major point and nonpoint sources of nutrient pollution to surface water have declined throughout the Chesapeake Bay watershed

Sabo RD, Sullivan B, Wu C, Trentacoste E, Zhang Q, Shenk GW, Bhat G and Linker LC ·
2022

Understanding drivers of water quality in local watersheds is the first step for implementing targeted restoration practices. Nutrient inventories can inform water quality management decisions by identifying shifts in nitrogen (N) and phosphorus (P) balances over space and time while also keeping track of the likely urban and agricultural point and nonpoint sources of pollution.

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