Open Access. Powered by Scholars. Published by Universities.®

Environmental Monitoring Commons

Open Access. Powered by Scholars. Published by Universities.®

Life Sciences

Series

Institution
Keyword
Publication Year
Publication
File Type

Articles 1 - 30 of 1161

Full-Text Articles in Environmental Monitoring

Heavy Metals Implications To Sediment Microbiome And Coral Response To Arsenic Dosing, Dimitrios G. Giarikos, Amy Hirons, Jose V. Lopez, Abigail Renegar, Jason Gershman Jun 2024

Heavy Metals Implications To Sediment Microbiome And Coral Response To Arsenic Dosing, Dimitrios G. Giarikos, Amy Hirons, Jose V. Lopez, Abigail Renegar, Jason Gershman

SECLER Data

No abstract provided.


Agricultural Groundcover Update March 2024, Justin Laycock May 2024

Agricultural Groundcover Update March 2024, Justin Laycock

Natural resources published reports

  • In March, over 10% (1,577,000 ha) of the arable farmland in the south-west of Western Australia had less than 50% vegetative groundcover, which is inadequate to prevent wind erosion.
  • The northern grainbelt had the highest risk of wind erosion and over 20% of this farmland had inadequate groundcover.
  • About 1.3% (191,000 ha) of arable land had a high to very high risk of wind erosion because groundcover was less than 30%.


Understanding The Connection Between Water, Fish, And Pfas Concentrations: Implications Of Fish Diet And Species-Specific Variability, Ece Yeldan May 2024

Understanding The Connection Between Water, Fish, And Pfas Concentrations: Implications Of Fish Diet And Species-Specific Variability, Ece Yeldan

Honors College

Perfluoroalkyl and polyfluoroalkyl substances, commonly known as PFAS or “forever chemicals,” have emerged as a significant concern for both human health and the environment. These persistent compounds permeate various aspects of commerce, leading to widespread exposure and the cycling of these compounds through environmental feedback routes. Among the sources of exposure to humans, fish consumption stands out prominently. Recreational and sustenance fishing, cherished by Maine residents and indigenous communities alike, underscores the need to comprehend PFAS dynamics in fish and water. To explore the variability of PFAS accumulation in fish, water, and sediment, I conducted a comprehensive literature review. The …


Rescape: Transforming Coral-Reefscape Images For Quantitative Analysis, Zachary Ferris, Eraldo Ribeiro, Tomofumi Nagata, Robert Van Woesik Apr 2024

Rescape: Transforming Coral-Reefscape Images For Quantitative Analysis, Zachary Ferris, Eraldo Ribeiro, Tomofumi Nagata, Robert Van Woesik

Ocean Engineering and Marine Sciences Faculty Publications

Ever since the first image of a coral reef was captured in 1885, people worldwide have been accumulating images of coral reefscapes that document the historic conditions of reefs. However, these innumerable reefscape images suffer from perspective distortion, which reduces the apparent size of distant taxa, rendering the images unusable for quantitative analysis of reef conditions. Here we solve this century-long distortion problem by developing a novel computer-vision algorithm, ReScape, which removes the perspective distortion from reefscape images by transforming them into top-down views, making them usable for quantitative analysis of reef conditions. In doing so, we demonstrate the …


Demographic Consequences Of Off-River Nesting For Piping Plover (Charadrius Melodus) And Interior Least Tern (Sternula Antillarum Athalassos) In The Lower Platte River System, Nebraska, Elsa M. Forsberg Apr 2024

Demographic Consequences Of Off-River Nesting For Piping Plover (Charadrius Melodus) And Interior Least Tern (Sternula Antillarum Athalassos) In The Lower Platte River System, Nebraska, Elsa M. Forsberg

School of Natural Resources: Dissertations, Theses, and Student Research

Piping plovers (Charadrius melodus; hereafter, plovers) and interior least terns (Sternula antillarum athalassos; hereafter, terns) are two avian species that nest along the Lower Platte River system (LPRS) in Nebraska. In the LPRS, river sandbars provide natural nesting habitat, but off-river sites provide substantial nesting habitat especially when sandbar habitat is scarce. Although presumed to be important for the persistence of plovers and terns, off-river habitat is not self-sustaining and predicted to decline. Understanding the vital rates of plovers and terns in the LPRS will inform the role of off- river sites in the future conservation …


Agricultural Groundcover Update February 2024, Justin Laycock Apr 2024

Agricultural Groundcover Update February 2024, Justin Laycock

Natural resources published reports

  • About 92% of the grainbelt had adequate (more than 50%) vegetative groundcover to prevent wind erosion in February 2024.
  • Nearly 8% of the grainbelt (1,193,400 ha) had less than 50% groundcover, which is inadequate to prevent wind erosion.
  • The northern grainbelt had the highest risk of wind erosion and 16.5% of this farmland had inadequate groundcover.
  • Less than 0.7% of the grainbelt had a high to very high risk of wind erosion because groundcover was less than 30%.


Procedures For Rangeland Condition Assessment In The Pilbara And Southern Rangelands 2022, Department Of Primary Industries And Regional Development Apr 2024

Procedures For Rangeland Condition Assessment In The Pilbara And Southern Rangelands 2022, Department Of Primary Industries And Regional Development

Natural resources published reports

To define the procedures used in 2022 by the Department of Primary Industries and Regional Development (DPIRD) to complete rangeland condition assessment (RCA) in the Pilbara and southern rangelands region which has predominantly shrub-based pastures. For the rest of the pastoral estate, DPIRD uses the Procedures for RCA in the Kimberley which has grass pastures.

RCA is the process DPIRD uses to make systematic, lease level assessment of rangeland. Rangeland condition considers both the condition of pastures (as defined in the Pasture condition and management guide for the Pilbara rangelands or Southern rangelands pasture condition and management guides) and soils …


Ecological Monitoring Program At Vims Esl: Annual Report 2023, Paige G. Ross, Richard A. Snyder Apr 2024

Ecological Monitoring Program At Vims Esl: Annual Report 2023, Paige G. Ross, Richard A. Snyder

Reports

An Ecological Monitoring Program (EMP) has been established at the Virginia Institute of Marine Science Eastern Shore Laboratory (VIMS ESL) for the coastal environment near the Wachapreague lab. The goals of the initiative are to 1) provide status and trends information to scientists who study and regulators who manage Virginia’s marine resources, 2) provide a scientific context for short-term research and grant proposals 3) provide pedagogical enrichment for educators to use in their classes, and 4) build capacity in staff expertise and training of interns and students at VIMS ESL.

The program formalizes and standardizes data collection for a long-term …


Procedures For Rangeland Condition Assessment In The Kimberley 2022, Department Of Primary Industries And Regional Development Mar 2024

Procedures For Rangeland Condition Assessment In The Kimberley 2022, Department Of Primary Industries And Regional Development

Natural resources published reports

This report defines the procedures used in 2022 by the Department of Primary Industries and Regional Development (DPIRD) to complete rangeland condition assessment (RCA) in the Kimberley region which has grass-based pastures. For the rest of the pastoral estate, DPIRD uses the Procedures for RCA in the Pilbara and southern rangelands which have predominantly shrub pastures.

RCA is the process DPIRD uses to make systematic, lease-level assessment of rangeland. Rangeland condition considers both the condition of pastures (as defined in the Pasture condition guide for the Kimberley, Ryan et al. 2013) and soils as determined by erosion, using the …


Agricultural Groundcover Update January 2024, Justin Laycock Feb 2024

Agricultural Groundcover Update January 2024, Justin Laycock

Natural resources published reports

Summary

  • About 94% of the grainbelt had adequate (more than 50%) vegetative groundcover to prevent wind erosion in January 2024.
  • In the northern half of the grainbelt, a larger-than-average area has 51–60% groundcover, which is expected to decrease to below 50% over the coming months.
  • Just under 6% of the grainbelt (855,000 ha) had less than 50% groundcover, which is inadequate to prevent wind erosion. West Midlands Ag Soil Zone had the highest risk of wind erosion and 14.5% of this farmland had inadequate groundcover.
  • Less than 0.5% of the grainbelt had a high to very high risk of wind …


Fauna, Flora, And Land Cover Changes Over The Last Two Decades In The Mobile-Tensaw River Delta, Gabriel De Oliveria, Steven R. Schultze, Guilherme Mataveli Jan 2024

Fauna, Flora, And Land Cover Changes Over The Last Two Decades In The Mobile-Tensaw River Delta, Gabriel De Oliveria, Steven R. Schultze, Guilherme Mataveli

Technical Reports

A technical report documenting ecosystem changes to the Mobile-Tensaw River Delta region due to urban expansion over approximately two decades (2001-2019).


Agricultural Groundcover Update December 2023, Justin Laycock Jan 2024

Agricultural Groundcover Update December 2023, Justin Laycock

Natural resources published reports

Summary

  • About 96% of the grainbelt had adequate vegetative groundcover (more than 50%) to prevent wind erosion in December 2023.
  • In the northern half of the grainbelt, a larger-than-average area has 51–60% groundcover, which is expected to decrease to below 50% over the summer.
  • Just under 4% of the grainbelt (553,000 ha) had less than 50% groundcover, which is inadequate to prevent wind erosion. West Midlands Ag Soil Zone had the highest risk of wind erosion and 11.4% of this farmland had inadequate groundcover.
  • Less than 0.5% of the grainbelt had a high to very high risk of wind erosion …


Our Community Legacy: What Oakville Will Our Children And Grandchildren Inherit, Lisa Kohler, Peter Schuler, Marsha Smith, Sundus Hussain, John Helliker, Herbert Sinnock, Caroline Holmes, Jonathan Mcneice, Trisha Henderson, Taline Mcphedran, Michael Salem Jan 2024

Our Community Legacy: What Oakville Will Our Children And Grandchildren Inherit, Lisa Kohler, Peter Schuler, Marsha Smith, Sundus Hussain, John Helliker, Herbert Sinnock, Caroline Holmes, Jonathan Mcneice, Trisha Henderson, Taline Mcphedran, Michael Salem

Publications and Scholarship

No abstract provided.


Status Of The Western Australian Pastoral Rangelands 2023: Total Vegetative Cover And Cover Risk, Department Of Primary Industries And Regional Development Dec 2023

Status Of The Western Australian Pastoral Rangelands 2023: Total Vegetative Cover And Cover Risk, Department Of Primary Industries And Regional Development

Natural resources published reports

The Department of Primary Industries and Regional Development (DPIRD) monitors and reports on the vegetation condition of pastoral rangelands in Western Australia. This 2023 short report uses remotely sensed total cover data available to the end of October 2023, rainfall data to the end of November 2023 and Stock Return data reported in 2022 (the most recent available) to determine cover risk. Cover risk at the land conservation district (LCD) level is an indicator of the likelihood of total cover declining to, or remaining at, low or very low levels. Total cover and cover risk may not be indicative of …


Agricultural Groundcover Update November 2023, Justin Laycock Dec 2023

Agricultural Groundcover Update November 2023, Justin Laycock

Natural resources published reports

Summary

  • About 98% of the grainbelt had adequate (more than 50%) vegetative groundcover to prevent wind erosion in November 2023. This amount of groundcover is normal for the middle of harvest.
  • In the northern half of the grainbelt, a larger-than-average area had 51–60% groundcover, which is expected to decrease to below 50% over summer.
  • Just over 2% of the grainbelt (324,000 ha) had less than 50% groundcover, which is inadequate to prevent wind erosion. Mullewa to Morawa Ag Soil Zone had the highest risk of wind erosion and 9.7% of this farmland had inadequate groundcover.
  • Less than 0.5% of the …


Agricultural Groundcover Update October 2023, Justin Laycock Nov 2023

Agricultural Groundcover Update October 2023, Justin Laycock

Natural resources published reports

Summary

  • About 98% of the grainbelt had adequate vegetative groundcover (more than 50%) to prevent wind erosion in October 2023. This amount of groundcover is normal at the end of spring and pre-harvest in most areas.
  • There was a larger than average area with 51–60% groundcover, and groundcover in these areas is expected to reduce over summer to below 50%.
  • About 2% of the grainbelt (293,000 ha) had less than 50% groundcover, which is inadequate to prevent wind erosion. Mullewa to Morawa Ag Soil Zone had the highest risk of wind erosion and 8% of this farmland had inadequate groundcover. …


The Coastal Monitor: Vol. 10 No. 2, John Tanacredi Ph.D. Oct 2023

The Coastal Monitor: Vol. 10 No. 2, John Tanacredi Ph.D.

The Coastal Monitor

Stephen J. Gould’s prophetic piece, “The Golden Rule: A Proper Scale for Our Environmental Crisis”, noted that, “Patience enjoys a long pedigree of favor”, which he elaborated, “usually involves a deep understanding of the fundamental principle… rarely grasped in daily life – the effects of scale.” Scientists observe changes incessantly, in dimensions and time, from microscopic conditions of cellular biology to the inconceivable distances of galaxies and their influences on Earth.


On The Rocks, Below The Rocks: A Study Of Intertidal Life In The Low, Middle And High Zones Of The Puerto Cabuyal – Punta San Clemente Marine Reserve During An El Niño Event, Juliana M. Ferrer Oct 2023

On The Rocks, Below The Rocks: A Study Of Intertidal Life In The Low, Middle And High Zones Of The Puerto Cabuyal – Punta San Clemente Marine Reserve During An El Niño Event, Juliana M. Ferrer

Independent Study Project (ISP) Collection

The rocky intertidal zone is one of the most difficult environments for organisms to survive in due to its harsh biotic and abiotic conditions. As such, it is also one of the best indicators of climate change and an important barrier to beach erosion. This study looked at the rocky intertidal zone of the Puerto Cabuyal-Punta San Clemente Marine Reserve in the Manabí province of Ecuador, with a focus on observing and identifying the organisms found in the area. Data was collected along 30 m transects at varying elevations along the shore using quadrants of two sizes: 50x50 cm for …


Community Complexity Of A Pollination Network: Analysis Of Plant-Pollinator Interactions In The Eastern Ecuadorian Cloud Forest, Anisa López-Ruiz Oct 2023

Community Complexity Of A Pollination Network: Analysis Of Plant-Pollinator Interactions In The Eastern Ecuadorian Cloud Forest, Anisa López-Ruiz

Independent Study Project (ISP) Collection

Global declines in pollinators and temporal/spatial mismatches between plants and pollinators threaten the integrity of plant-pollinator networks. Ecological network analysis provides a powerful framework for understanding the dynamics of plant-pollinator networks and measures of community complexity that can help inform areas of priority in conservation. This study observed a plant-pollinator network in a secondary forest close to the Río Zuñac Reserve in the eastern Ecuadorian cloud forest to identify assemblages of plants and pollinators and evaluate measures of community complexity, including specialization and nestedness. Flowering plants were identified and observed along a 1.2 km transect, and floral visitors to these …


Analyzing Human - Nonhuman Primate Conflict Mitigation Techniques In Mto Wa Mbu, Northern Tanzania, Lily Adams Oct 2023

Analyzing Human - Nonhuman Primate Conflict Mitigation Techniques In Mto Wa Mbu, Northern Tanzania, Lily Adams

Independent Study Project (ISP) Collection

Human – non-human primate conflict is particularly crucial due to primates’ high capacity to live among human populations. The study to analyze Human - Nonhuman Primate Conflict Mitigation Techniques, was carried in November 2023 at Mto wa Mbu, Northern Tanzania. To analyze techniques currently being used to mitigate human – non-human primate conflict, this study collected data through semi-structured interviews. Over 87% (n=35) of respondents used multiple mitigation techniques simultaneously. 80% of respondents (n=32) reported using projectiles to ward off foraging primates, 75% of respondents (n=30) reported using loud noises (made either by the voice/body or by manipulating noisemakers), 67.5% …


Friends In High Places: Establishing Pollination Networks For The Páramos Of Central Ecuador, Emma Diaz Oct 2023

Friends In High Places: Establishing Pollination Networks For The Páramos Of Central Ecuador, Emma Diaz

Independent Study Project (ISP) Collection

Well-known for being a global biodiversity hotspot, the Andean Páramos hosts a unique array of floristic diversity seen nowhere else in the world (Luteyn, n.d.). With the resiliency of this ecosystem dependent on the successful reproduction of these plants, it is crucial to understand the pollination network which sustains them. Modern-day research has outlined networks in the Chilean, Venezuelan, and Argentinean Páramos, but one has yet to be defined for Ecuador, despite being the suspected home to nearly half of floristic diversity in the Páramos (Arroyo et al., 1985; Pelayo et al., 2021; Medan et al., 2023; Caranqui et al., …


Waterbody Size Predicts Bank- And Boat-Angler Efforts, Derek S. Kane, Kevin L. Pope, Keith D. Koupal, Mark A. Pegg, Christopher J. Chizinski, Mark A. Kaemingk Jul 2023

Waterbody Size Predicts Bank- And Boat-Angler Efforts, Derek S. Kane, Kevin L. Pope, Keith D. Koupal, Mark A. Pegg, Christopher J. Chizinski, Mark A. Kaemingk

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Bank- and boat-angler efforts are logistically difficult and costly to estimate, preventing landscape-scale estimates that are required to address current and future challenges (e.g., climate change, invasive species) for inland recreational fisheries. Using a large Nebraska, USA, recreational fishery dataset (N = 67 waterbodies), we demonstrate that waterbody size can be used to predict bank- and boat-angler efforts across a heterogeneous landscape of extra small (< 104 ha) and large (> 647 ha) waterbodies. Bank and boat anglers respond to waterbody size, however these relationships appear to be unique between the two angler types. Boat-angler efforts increased as a function of waterbody size, whereas bank-angler …


Managing Water Quality To Enable Future Irrigation Development In The Kimberley Region: Three-Dimensional Hydrodynamic Modelling To Evaluate The Effect Of Farm Chemicals On The Lower Pools Of The Keep River, J Romero Jun 2023

Managing Water Quality To Enable Future Irrigation Development In The Kimberley Region: Three-Dimensional Hydrodynamic Modelling To Evaluate The Effect Of Farm Chemicals On The Lower Pools Of The Keep River, J Romero

Natural resources commissioned reports

The National Water Grid Authority awarded the Department of Primary Industries and Regional Development (DPIRD) a project entitled ‘Managing Water Quality to Enable Future Irrigation Development in the Kimberley Region’.

The purpose of the project is to review the current and future risk profile of agrichemicals (pesticides) in the Keep River catchment (Ord - East Kimberley) in the context of irrigation development across the last decade and proposed in the medium term. The results of the review were to define prospective mitigation and risk management practices to be developed in consultation with the Goomig and Knox Plains Independent Review Group …


Report On And Recommendations Arising From The Visit Of Dr Michael Warne (University Of Queensland) And Robert Sluggett To Kununurra, Michael Warne Dr, Rob Sluggett Jun 2023

Report On And Recommendations Arising From The Visit Of Dr Michael Warne (University Of Queensland) And Robert Sluggett To Kununurra, Michael Warne Dr, Rob Sluggett

Natural resources commissioned reports

Dr Michael Warne of the Reef Catchments Science Partnership and Robert Sluggett of Farmacist Pty Ltd were invited by Richard George of Department of Primary Industries and Regional Development (DPIRD) to visit Kununurra, Western Australia.

The project was financially supported by the National Water Grid Authority project “Managing water quality to enable future irrigation development in the Kimberley Region”. The aim of the visit was for Dr Warne and Rob Sluggett to engage with farmers, key stakeholders and staff from DPIRD in order to understand the agriculture and water quality in the Ord and Keep river region; and to share …


Spatial And Temporal Activity Patterns Among Sympatric Tree-Roosting Bat Species In An Agriculturally Dominated Great Plains Landscape, Christopher Fill, Craig R. Allen, John F. Benson, Dirac Twidwell Jun 2023

Spatial And Temporal Activity Patterns Among Sympatric Tree-Roosting Bat Species In An Agriculturally Dominated Great Plains Landscape, Christopher Fill, Craig R. Allen, John F. Benson, Dirac Twidwell

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

In agroecosystems, bats can provide a critical ecosystem service by consuming night-flying insect pests. However, many bats also face intense population pressures from human landscape modification, global change and novel diseases. To better understand the behavioral activity of different bat species with respect to space, time, habitat, and other bat species in this environment, we investigated species correlations in space and time over row crop agricultural fields. We used acoustic grids to document spatial and temporal co-occurrence or avoidance between bats and recorded eight species across the 10 field sites we sampled. All species significantly overlapped in two-dimensional space and …


The Coastal Monitor: Vol. 10 No. 1, John Tanacredi Ph.D. Apr 2023

The Coastal Monitor: Vol. 10 No. 1, John Tanacredi Ph.D.

The Coastal Monitor

New Year’s Day has always been, for me, a time to reflect and project into the near future. Nature’s influence on us all certainly tops my listing with several environmental concerns. For example, the frequency and intensity of hurricanes to Long Island. A decade has passed since Superstorm Sandy re-opened the “Old Inlet” on Long Island which now has mostly naturally closed. So, the new year immediately prompts me to assess the previous year’s Hurricane Ian, a Category 4 system, with winds exceeding 150 mph, which had considerable impact in Florida, and then proceeded north resulting in over 2 inches …


Spatial Ecology And Habitat Preference Of Yellow-Spotted Monitors (Varanus Panoptes) At Lizard Island National Park, Qld, Australia, Ryan Snyder Apr 2023

Spatial Ecology And Habitat Preference Of Yellow-Spotted Monitors (Varanus Panoptes) At Lizard Island National Park, Qld, Australia, Ryan Snyder

Independent Study Project (ISP) Collection

Lizard Island National Park is an area of strong habitat diversity, especially given its small size. There are several distinct habitats represented, including open sclerophyll woodlands, mangrove swamps, dune grasslands, foothills elevations, and of course anthropogenically modified human habitats. The object of this study was to observe the abundances and behaviors of the yellow-spotted monitor lizard (V. panoptes) in each of these habitat settings to answer the question of which habitat type is preferred amongst V. panoptes in the landscape context of Lizard Island National Park.

Study transects were conducted over the course of one month measuring abundance of V. …


Impact Of Wildlife Provisioning On Species Diversity, Relative Frequency, And Richness In New South Wales, Alanah Cohen-Tigör Apr 2023

Impact Of Wildlife Provisioning On Species Diversity, Relative Frequency, And Richness In New South Wales, Alanah Cohen-Tigör

Independent Study Project (ISP) Collection

Wildlife provisioning and camera trapping are two recently evolving methods of conservation and wildlife management, aimed at protecting animals in the face of ever worsening climate change. Habitats are being destroyed by climate disruption, decreasing species diversity and abundance worldwide. It is imperative that methods of protecting species are developed to slow or reverse this era of extinction. By providing supplementary food and water to ecological communities, the hope is that species will have improved survivorship and reproduction, making them more resilient and resistant to population decline. Camera trapping is product of modern technology, allowing researchers to monitor species without …


Individual-Level Responses To Rapid Climate Change In Common Terns (Sterna Hirundo) And Arctic Terns (Sterna Paradisaea), Kaiulani A. Sund Apr 2023

Individual-Level Responses To Rapid Climate Change In Common Terns (Sterna Hirundo) And Arctic Terns (Sterna Paradisaea), Kaiulani A. Sund

Student Publications

This study examines fine-scale environmental changes and intraspecific variation in the diet and foraging behavior of two seabirds in the Gulf of Maine, one of the fastest-warming regions of the ocean. This variation on the individual level, or behavioral plasticity, may help long-lived species to persist in rapidly changing environments. As the water warms, seabirds’ preferred prey (hake and herring) follow cooler waters deeper and farther offshore. It is unlikely that all individuals respond to changing food availability in the same way. For common terns (Sterna hirundo) and Arctic terns (Sterna paradisaea) breeding on Petit Manan …


Diverse Portfolios: Investing In Tributaries For Restoration Of Large River Fishes In The Anthropocene, Kristen L. Bouska, Brian D. Healy, Michael J. Moore, Corey G. Dunn, Jonathan J. Spurgeon, Craig P. Paukert Mar 2023

Diverse Portfolios: Investing In Tributaries For Restoration Of Large River Fishes In The Anthropocene, Kristen L. Bouska, Brian D. Healy, Michael J. Moore, Corey G. Dunn, Jonathan J. Spurgeon, Craig P. Paukert

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Rehabilitation of large Anthropocene rivers requires engagement of diverse stakeholders across a broad range of sociopolitical boundaries. Competing objectives often constrain options for ecological restoration of large rivers whereas fewer competing objectives may exist in a subset of tributaries. Further, tributaries contribute toward building a “portfolio” of river ecosystem assets through physical and biological processes that may present opportunities to enhance the resilience of large river fishes. Our goal is to review roles of tributaries in enhancing mainstem large river fish populations. We present case histories from two greatly altered and distinct large-river tributary systems that highlight how tributaries contribute …