Biology subjects

Madin, J.

Publications and source records attributed to Madin, J..

3 recordsLinked to original sources

bioRxiv2021

Selecting species for restoration in foundational assemblages

O_LIHumans have long sought to restore species, but little attention has been directed at how to best select a subset of foundation species for maintaining rich assemblages that support ecosystems, like coral reefs and rainforests that are increasingly threatened by environmental change. C_LIO_LIWe propose a two-part hedging approach that selects optimized sets of species for restoration. The first part acknowledges that biodiversity supports ecosystem functions and services, and so it takes precaution against loss by ensuring an even spread of phenotypic traits. The second part maximizes species and ecosystem persistence by weighting species based on characteristics that are known to improve ecological persistence--e.g., abundance, species range and tolerance to environmental change. C_LIO_LIUsing existing phenotypic trait and ecological characteristic data for reef building corals, we identified sets of ecologically persistent species by examining marginal returns in occupancy of phenotypic trait space. We compared optimal sets of species with those from the worlds southern-most coral reef which naturally harbors low coral diversity to show these occupy much of the trait space. Comparison with an existing coral restoration program indicated that current corals used for restoration only cover part of the desired trait space and may be improved by including species with different traits. C_LIO_LISynthesis and applications. While there are many possible criteria for selecting species for restoration, the approach proposed here addresses the need to insure against unpredictable losses of ecosystem services by focusing on a wide range of phenotypic traits and ecological characteristics. Furthermore, the flexibility of the approach enables the functional goals of restoration to vary depending on environmental context, stakeholder values, and the spatial and temporal scales at which meaningful impacts can be achieved. C_LI

ecology↗

bioRxiv2021

Genetic patterns in Montipora capitata across an environmental mosaic in Kaneohe Bay

Spatial genetic structure (SGS) is important to a populations ability to adapt to environmental change. For species that reproduce both sexually and asexually, the relative contribution of each reproductive mode has important ecological and evolutionary implications because asexual reproduction can have a strong effect on SGS. Reef building corals reproduce sexually, but many species also propagate asexually under certain conditions. In order to understand SGS and the relative importance of reproductive mode across environmental gradients, we evaluated genetic relatedness in almost 600 colonies of Montipora capitata across 30 environmentally characterized sites in K[a]neohe Bay, Oahu, Hawaii using low-depth restriction digest associated sequencing. Clonal colonies were relatively rare overall but influenced SGS. Clones were located significantly closer to one another spatially than average colonies and were more frequent on sites where wave energy was relatively high, suggesting a strong role of mechanical breakage in their formation. Excluding clones, we found no evidence of isolation by distance within sites or across the bay. Several environmental characteristics were significant predictors of the underlying genetic variation (including degree heating weeks, time spent above 30{degrees}C, depth, sedimentation rate and wave height); however, they only explained 5% of this genetic variation. Our results show that colony fragmentation contributes to the ecology of M. capitata at local scales and that genetic diversity is maintained despite strong environmental gradients in a highly impacted ecosystem, suggesting potential for broad adaptation or acclimatization in this population.

ecology↗

bioRxiv2019

Valuing Carbon Stocks across a Tropical Lagoon after Accounting for Black and Inorganic Carbon: Bulk Density Proxies for monitoring

Managing seagrass and mangrove can be enhanced through carbon valued payment incentives schemes. Success will depend on the accuracy and extent of the carbon stock mitigation and accessible methods of monitoring and marking changes. In a relatively closed socioecological Southeast Asian lagoon we estimated the value of total organic carbon stocks (TOC) of both seagrass and mangroves. Mitigation corrections were also made for black carbon (BC) and calcareous inorganic carbon equivalents (PICequiv), and their sediment dry bulk density (DBD) tested as a cost effective means of both estimating those stock concepts and possible impacts outside their parameter confidence intervals. Overall, seagrass and mangroves TOC densities across the lower lagoon ranged from 15.3{+/-}4.3 and 124.3{+/-}21.1 Mg C ha-1 respectively, 175.2{+/-}46.9 and 103.2{+/-}19.0 Mg C ha-1 for seagrass and 355.0{+/-}24.8 and 350.3{+/-}35.2 Mg C ha-1) for mangroves across the two upper lagoon branches. Only mangrove biomass made significant additional contributions ranging from 178.5{+/-}62.3 to 120.7{+/-}94.8 Mg C ha-1 for lower and upper regions respectively. The difference between the lagoons total seagrass and mangroves TOC stocks (5.98{+/-}0.69 and 390{+/-}33.22 GgC respectively) was further amplified by the lagoons larger mangrove area. When corrected for BC and PICequiv, the carbon stock mitigation was only reduced by a moderate 14.2%. Across the lagoon the sedimentary DBD showed strong (R2 = 0.85, P < 0.001) to moderate (R2 = 0.67, P < 0.001) linear correlations with seagrass and mangrove [TOC] respectively, moderate correlations with seagrass [PIC] (R2 = 0.6, P < 0.001), but an invariant and relatively constant response to mangrove [PIC] (2.7 kg m-3 {+/-} 0.07). Valuations as CO2e was worth on average 0.44 million US$ y-1 over 20 years; less than the total income of the indigenous users as potential custodians (1.8 and 7.4 million US$ y-1). Implications of this valuation was discussed.

plant biology↗