Variability in nitrogen content of submerged aquatic vegetation: utility as an indicator of N dynamics within and among lakes

Submerged aquatic vegetation (SAV) may serve as an integrative proxy of spatial and temporal nitrogen (N) availability in aquatic ecosystems as plants are physiologically capable of storing variable amounts of N. However, it is important to understand whether plant species behave similarly or differently within and among systems. We sampled different SAV species along a nutrient gradient at multiple sites within several lakes to determine variability in C:N ratios and % N content among species, among plants of the same species at a single site, among sites and among lakes. Species respond differently suggesting that not all plant types can be used universally as nutrient proxies. The greatest variability in % N and C:N ratios for Valliseneria americana was observed among lakes whereas for Elodea canadensis it was among sites within a lake and among plants within a site. This suggests that V. americana could be a particularly useful indicator of N availability at larger spatial scales (regional and within a large fluvial lake) but that E. canadensis was not a particularly useful proxy.

Download Full-text

Spatial structuring of submerged aquatic vegetation in an estuarine habitat of the Gulf of Mexico

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315412000677 ◽

2012 ◽

Vol 93 (4) ◽

pp. 855-866 ◽

Cited By ~ 5

Author(s):

Aretha Moriana Burgos-León ◽

David Valdés ◽

Ma. Eugenia Vega ◽

Omar Defeo

Keyword(s):

Spatial Structure ◽

Environmental Variables ◽

Submerged Aquatic Vegetation ◽

Aquatic Vegetation ◽

Spatial Scales ◽

Ruppia Maritima ◽

Spatial Partitioning ◽

Estuarine Habitat ◽

Relative Contribution ◽

Geostatistical Techniques

Seasonal changes in spatial structure of biomass of submerged aquatic vegetation (SAV) and environmental variables were evaluated in Celestun Lagoon, an estuarine habitat in Mexico. Geostatistical techniques were used to evaluate spatial autocorrelation and to predict the spatial distribution by kriging. The relative contribution of 11 environmental variables in explaining the spatial structure of biomass of SAV was evaluated by canonical correspondence analysis. Spatial partitioning between species of SAV was evident: the seagrasses Halodule wrightii and Ruppia maritima dominated the seaward and central zones of the lagoon, respectively, whereas the green alga Chara fibrosa was constrained to the inner zone. The spatial structure and seasonal variability of SAV biomass were best explained by organic carbon in the sediments, salinity and total suspended solids in the water column. Analysis at different spatial scales allowed identifying the importance of spatial structure in biotic and abiotic variables of this estuarine habitat.

Download Full-text

A Comparison of Planting Techniques for Submerged Aquatic Vegetation

EDIS ◽

10.32473/edis-ss685-2020 ◽

2020 ◽

Vol 2020 (4) ◽

Author(s):

Laura K. Reynolds ◽

Carrie Reinhardt Adams ◽

Enrique Latimer ◽

Charles W. Martin ◽

Christine E. Rohal ◽

...

Keyword(s):

Water Quality ◽

Food Web ◽

Aquatic Ecosystems ◽

Submerged Aquatic Vegetation ◽

Aquatic Vegetation ◽

Multiple Methods ◽

Plant Survival ◽

New Locations ◽

Soil And Water ◽

Important Habitat

Submerged aquatic vegetation has numerous benefits for aquatic ecosystems, from improving water quality to providing important habitat that supports a diverse food web. This new 6-page publication of the UF/IFAS Department of Soil and Water Sciences describes the breadth of options available to managers who wish to plant SAV at new locations. Because all methods have both benefits and drawbacks, and because all planting locations have different (often unknown) challenges for plant survival, managers may choose to try multiple methods to increase the likelihood for success. Written by Laura Reynolds, Carrie Reinhardt Adams, Enrique Latimer, Charles W. Martin, Christine Rohal, and Jodi Slater.https://edis.ifas.ufl.edu/ss685

Download Full-text

Open-Source Analysis of Submerged Aquatic Vegetation Cover in Complex Waters Using High-Resolution Satellite Remote Sensing: An Adaptable Framework

Remote Sensing ◽

10.3390/rs14020267 ◽

2022 ◽

Vol 14 (2) ◽

pp. 267

Author(s):

Arthur de Grandpré ◽

Christophe Kinnard ◽

Andrea Bertolo

Keyword(s):

Remote Sensing ◽

Image Analysis ◽

High Resolution ◽

Submerged Aquatic Vegetation ◽

Aquatic Vegetation ◽

Spatial Scales ◽

Atmospheric Correction ◽

Source Analysis ◽

Radiometric Calibration ◽

Ecological Data

Despite being recognized as a key component of shallow-water ecosystems, submerged aquatic vegetation (SAV) remains difficult to monitor over large spatial scales. Because of SAV’s structuring capabilities, high-resolution monitoring of submerged landscapes could generate highly valuable ecological data. Until now, high-resolution remote sensing of SAV has been largely limited to applications within costly image analysis software. In this paper, we propose an example of an adaptable open-sourced object-based image analysis (OBIA) workflow to generate SAV cover maps in complex aquatic environments. Using the R software, QGIS and Orfeo Toolbox, we apply radiometric calibration, atmospheric correction, a de-striping correction, and a hierarchical iterative OBIA random forest classification to generate SAV cover maps based on raw DigitalGlobe multispectral imagery. The workflow is applied to images taken over two spatially complex fluvial lakes in Quebec, Canada, using Quickbird-02 and Worldview-03 satellites. Classification performance based on training sets reveals conservative SAV cover estimates with less than 10% error across all classes except for lower SAV growth forms in the most turbid waters. In light of these results, we conclude that it is possible to monitor SAV distribution using high-resolution remote sensing within an open-sourced environment with a flexible and functional workflow.

Download Full-text

Does the relative value of submerged aquatic vegetation for penaeid shrimps vary with proximity to a tidal inlet? Preliminary evidence from a subtropical coastal lagoon

Marine and Freshwater Research ◽

10.1071/mf15207 ◽

2017 ◽

Vol 68 (3) ◽

pp. 581 ◽

Cited By ~ 7

Author(s):

Zeferino Blanco-Martínez ◽

Roberto Pérez-Castañeda

Keyword(s):

Submerged Aquatic Vegetation ◽

Aquatic Vegetation ◽

Explanatory Variable ◽

Coastal Lagoons ◽

Penaeid Shrimp ◽

Preliminary Evidence ◽

Tidal Inlet ◽

Relative Value ◽

A Site ◽

Shrimp Abundance

The value of submerged aquatic vegetation (SAV) as a nursery habitat for penaeid shrimp has been recognised previously; however, the importance of SAV in terms of its distance from a tidal inlet (a site through which shrimp postlarvae migrate into coastal lagoons) has not been evaluated. In the present study, the effect of proximity to a tidal inlet on the relative importance of SAV beds for Farfantepenaeus shrimp was evaluated in the Laguna Madre of Tamaulipas (Mexico). Sampling was performed monthly from February to December 2005, diurnally and nocturnally, in two SAV bed areas, one 25km (distant) and the other 1km (nearby) from the inlet. Densities of shrimp (F. aztecus, F. duorarum and F. brasiliensis) were consistently higher in the nearby SAV bed during both the day and night. Water temperature was the most important explanatory variable of shrimp abundance in both SAV beds. The temperature–abundance relationship was negative in all cases, except in the distant SAV bed at night, when shrimp abundance was positively related to dissolved oxygen and salinity. The nearby SAV bed had higher recruit abundance and supported a greater numbers of juveniles and subadults. In contrast, shrimp abundance in the distant SAV bed was apparently limited by recruitment.

Download Full-text