DOI: 10.5061/dryad.tx95x6b7g
title: Heavy metal contamination and blue carbon sequestration in mangrove ecosystems of Puerto Rico

description: Heavy metal contamination in coastal ecosystems can significantly impact
 biological activity, metal retention, and biogeochemical cycling. This
 study examined the levels of arsenic (As), cadmium (Cd), chromium (Cr),
 copper (Cu), nickel (Ni), lead (Pb), and zinc (Zn) in sediments and leaves
 of two mangrove ecosystems in Puerto Rico: La Parguera and Laguna Grande.
 We also evaluated ratios of metal concentrations in plants and soils,
 i.e., bioconcentration factors (BCF) and differences in metal
 concentrations between green and senescent (yellow) leaves, i.e.,
 retention percentages (RT%). Levels of metals at both sites were low
 relative to previous mangrove studies, but were markedly higher at the
 Laguna Grande site due to anthropogenic influences. Relationships between
 metals, between metals and sediment carbon, and metal retention and
 bioavailability also differed between the sites.  Results suggest
 that differences in relationships between metals and between metals and
 carbon may be useful for identifying sources and effects of metals.
 Further, metals with high retention by plant percentages, such as zinc and
 lead at La Parguera, suggest that plant-mediated stabilization processes
 can reduce immediate bioavailability but may pose latent risks under
 changing environmental conditions. Conversely, metals like cadmium and
 nickel, with low retention and high bioavailability at Laguna Grande,
 indicate greater potential for biological uptake and ecosystem stress.
 These findings underscore the critical role of site-specific environmental
 factors, such as metal loading, plant density, sediment chemistry, and
 hydrodynamics, in mediating metal behavior. Further research is needed to
 explore the direct physiological effects of metal exposure on plants and
 their implications for carbon storage and ecosystem health in
 mangrove-dominated systems.
description: # Heavy metal contamination and its influences on blue carbon in mangroves
 in Puerto Rico
 [https://doi.org/10.5061/dryad.tx95x6b7g](https://doi.org/10.5061/dryad.tx95x6b7g) ## Description of the data and file structure Heavy Metal Analysis of soil from sediment Cores and leaves of mangroves from Puerto Rican Mangroves were collected for biogeochemistry analysis. ### Files and variables #### File: Soil_Samples_-_Heavy_Metals_10-18-24.xlsx **Description:** The Excel sheet contains the raw heavy metal data from sediment cores from one study area in Puerto Rico. This dataset presents the concentration of selected metals (in ppm) in environmental or possibly biological samples identified by unique Sample IDs. It focuses on potentially toxic elements commonly monitored in environmental assessments. #### File: Soil_and_Plant_Data_Final_11-29-24.xlsx **Description:** The Excel sheet contains the raw heavy metal data and plant data from sediment cores from one study area in Puerto Rico. This dataset contains elemental concentration data (in ppm) from different environmental samples collected from various locations. It captures both toxic heavy metals (like arsenic and lead) and essential nutrients (like calcium and potassium). The table is structured for multiple replicates per location, allowing for comparisons across both sites and sample types. ## Code/software Microsoft Excel (for Windows), Google Sheets, or Pages (for Macs) are needed to view the data.