Biomass–density data analysis: a comment on <scp>C</scp>abaço <i>et al</i>. (2013)

Vieira, Vasco M. N. C. S.; Leitão, Francisco; Mateus, Marcos

doi:10.1111/1365-2745.12294

Cited by 3 publications

(3 citation statements)

References 20 publications

(23 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Monitoring seagrass health has been proposed for coastal water quality assessment [ 43 – 47 ]. The development of an ecological indicator relying exclusively on the biomass–density relation of seagrasses has been previously attempted, unsuccessfully [ 47 , 59 ]. At that time, the existence of a seagrass IBL and the fact that the efficiency of space occupation is a fundamental aspect of seagrass ecology were unknown.…”

Section: Discussionmentioning

confidence: 99%

The biomass–density relationship in seagrasses and its use as an ecological indicator

Vieira¹,

Lopes²,

Creed

2018

BMC Ecol

Self Cite

View full text Add to dashboard Cite

BackgroundBiomass–density relations have been at the centre of a search for an index which describes the health of seagrass meadows. However, this search has been complicated by the intricacy of seagrass demographics and their complex biomass–density relations, a consequence mainly of their modular growth and clonality. Concomitantly, biomass–density upper boundaries have been determined for terrestrial plants and algae, reflecting their asymptotic maximum efficiencies of space occupation. Each stand’s distance to its respective biomass–density upper boundary reflects its effective efficiency in packing biomass, which has proved a reliable ecological indicator in order to discriminate between taxonomic groups, functional groups and clonal vs. non-clonal growth.ResultsWe gathered data from 32 studies on 10 seagrass species distributed worldwide and demonstrated that seagrasses are limited by their own boundary line, placed below the boundaries previously determined for algae and terrestrial plants. Then, we applied a new metric—dgrass: each stand’s perpendicular distance to the seagrass boundary—and used this parameter to review fundamental aspects such as clonal growth patterns, depth distribution, seasonality, interspecific competition, and the effects of light, temperature and nutrients.ConclusionsSeagrasses occupy space less efficiently than algae and terrestrial plants. Using only their biomass and density data we established a new and efficient tool to describe space occupation by seagrasses. This was used with success to evaluate their meadows as an ecological indicator for the health of coastal ecosystems.Electronic supplementary materialThe online version of this article (10.1186/s12898-018-0200-1) contains supplementary material, which is available to authorized users.

show abstract

Section: Discussionmentioning

confidence: 99%

The biomass–density relationship in seagrasses and its use as an ecological indicator

Vieira¹,

Lopes²,

Creed

2018

BMC Ecol

Self Cite

View full text Add to dashboard Cite

show abstract

“…Patterns of trait variation were also visualized using principal component analysis (PCA) on the standardized variables. A particular focus was given to the covariation between Zostera marina densities and its above‐ and below‐ground biomass, as it can be indicative of the processes underlying seagrass demography (Cabaço et al., 2007, 2013;Vieira et al, 2015, 2018).…”

Section: Methodsmentioning

confidence: 99%

Drivers and limits of phenotypic responses in vulnerable seagrass populations:Zostera marinain the intertidal

et al. 2021

View full text Add to dashboard Cite

Intertidal seagrass meadows are exposed to both marine and terrestrial environmental constraints. Seagrass vulnerability to climate changes in these highly dynamic and thermally stressful environments is concerning. Using broadscale monitoring data covering contrasted intertidal environments, this study aims to provide a comprehensive view of the extent, drivers and potential limits of Zostera marina phenotypic responses. The links between phenotypic and reproductive strategies are also explored. Across 500 km of coastline, Z. marina exhibited extensive variations of density, morphology, above‐ and below‐ground biomass and rates of clonality. Variance partitioning of phenotypic traits confirmed the strong link between intertidal seagrass populations and broadscale climate variability. However, it also highlighted a non‐negligible role of local factors such as exposure regime, substrate and tidal cycles. In its response to the environment, Z. marina displayed a trade‐off between the density and size of shoots, leading to two distinct phenotypic types: high densities and low above‐ to below‐ground biomass ratios (Type 1) in response to both high hydrodynamic and temperature stress, and low densities, high above‐ground biomass per shoot and developed leaves and sheaths (Type 2) in the most stable and less stressful intertidal environments. We argue that Type 1 maximizes self‐facilitation whereas Type 2 minimizes intraspecific competition, and that their occurrence matches predictions from the stress‐gradient hypothesis (SGH). Building on the SGH, we propose a generalized response of seagrass to environmental changes and discuss the role of light as a potential limiting resource for intertidal meadows. Synthesis. Here, we show how the SGH can explain seagrass phenotypic responses, drawing on previous experimental results to provide relevant predictions across different stress gradients. We also show that Zostera marina responds to strong hydrodynamics and thermal constraints, both likely to increase in the intertidal with climate changes, with a facilitation‐maximizing phenotypic type (Type 1). This strategy appears incompatible with the competition‐minimizing Type 2 found when seagrass face resource limitation, such as light limitation induced by water quality degradation. This potential limit to the resilience of intertidal seagrass populations in the face of cumulative stressors raises concern about their vulnerability regarding future climate scenarios.

show abstract

“…Broader studies still face problems with numerical methods. Examples of this are the debate between Cabaco et al (2013) and Vieira et al (2015), or inadequate analyses such as flawed PCA applications lacking criteria to screen the meaningful principal components and the variables significantly contributing to each of these components. Concomitantly, the efficiency of space occupation and its related phalanx and guerrilla clonal growth forms were used as indicators of the health of seagrass meadows (Sintes et al, 2005) as well as of meadows of other clonal plants in wetlands and their response to environmental stressors (Chen et al, 2011(Chen et al, , 2014(Chen et al, , 2017Geremew et al, 2018).…”

Section: Introductionmentioning

confidence: 99%

Seagrasses benefit from mild anthropogenic nutrient additions

et al. 2022

Self Cite

View full text Add to dashboard Cite

Seagrasses are declining globally, in large part due to increased anthropogenic coastal nutrient loads that enhance smothering by macroalgae, attenuate light, and are toxic when in excessive concentrations of inorganic nitrogen and phosphorus. However, as sanitation is improved many seagrass meadows have been observed to recover, with a few studies suggesting that they may even benefit from mild anthropogenic nutrient additions. Monitoring seagrass demography and health has faced difficulties in establishing the adequate variables and metrics. Such uncertainty in the methods has caused uncertainty of the significance of results presented and compromised extrapolations to other seasons, areas, or species. One solution has come from within the plant self-thinning theories. During the 1980s, an interspecific boundary line (IBL) was determined as the upper limit of the combination of plant density and above-ground biomass for any stand on Earth, setting their maximum possible efficiency in space occupation. Recently, two meta-analyses to determine specific IBLs for algae and for seagrasses have been performed. The recently updated seagrass dataset comprises 5,052 observations from 78 studies on 18 species. These IBLs opened new perspectives for monitoring: the observed distance of a stand to the respective IBL (i.e., each stand’s relative efficiency of space occupation) was demonstrated to be a valuable indicator of a population’s health. Thus, this metric can be used to determine the impact of nutrients and pollutants on algae and seagrass populations. Furthermore, because the IBLs are common to all species, they may be used to compare all species from any location worldwide. This novel approach showed that Halodule wrightii, Halodule beaudettei, Halophila baillonii, Zostera marina, and Zostera noltei meadows benefit from anthropogenic additions of nitrogen and phosphorus, as long as these additions are moderate. In fact, the healthier Z. noltei meadows in Portugal (and among the healthiest meadows worldwide) were the ones exposed to effluents from wastewater treatment plants (WWTP) and a food factory. We conclude that those effluents are providing water with enough quality and that their optimal management should coordinate the technological solutions of the WWTP with the natural potential of seagrass meadows as water purifiers and biomass producers.

show abstract

Biomass–density data analysis: a comment on Cabaço et al. (2013)

Cited by 3 publications

References 20 publications

The biomass–density relationship in seagrasses and its use as an ecological indicator

The biomass–density relationship in seagrasses and its use as an ecological indicator

Drivers and limits of phenotypic responses in vulnerable seagrass populations:Zostera marinain the intertidal

Seagrasses benefit from mild anthropogenic nutrient additions

Contact Info

Product

Resources

About