Seagrasses are important keystone engineers in South African coastal environments, where they provide a range of critical services to both natural and human systems. However, seagrass ecosystems are increasingly threatened by anthropogenic impacts such as climate change and habitat loss and globally, as well as in South Africa seagrass cover is declining, seriously undermining ecosystem services. There have been repeated calls to investigate seagrass restoration to increase cover, biomass and ecosystem functions of seagrass populations. Previous research showed that success of restoration depends on a number of factors, including genomic and functional similarity between donor and transplant populations. In South Africa, there is a strong focus on ecological aspects and physiological performance of specific meadows, but the phenotypic and genomic responses to anthropogenic stressors are poorly understood.
Project SeaStore aims to provide critical information within the context of potentially restoring seagrass meadows in South Africa. Using ecological transcriptomics to quantify gene expression within and between populations sampled along an environmental gradient and measuring functional responses, we will be able to better understand the genomic and functional diversity in the region. In addition, under laboratory conditions we will experimentally manipulate anthropogenic stressors, including temperature, turbidity and nutrient loading to assess intra-and inter-population responses of seagrasses, which will provide insights into resilience and persistence. Our data will contribute towards developing an index of resilience of estuaries that is based on functional response data and allows us to evaluate how different seagrass populations might respond to change. Project SeaStore brings together a multidisciplinary team grounded in seagrass and climate change research, to provide maximum impact for restoration and conservation of this valuable resource.
Our seagrass work includes restoration trials, estimating blue carbon stored in seagrass meadows, microplastics in seagrass meadows, as well as micropropagation as a tool for restoration.
Selected key papers:
Mokumo MF, Adams JB, von der Heyden S. (2023) Investigating transplantation as a mechanism for seagrass restoration in South Africa. Restoration Ecology, 31: e13941
Boshoff B, Robinson-Smythe TB, von der Heyden S. (2023) The role of seagrass meadows in the accumulation of microplastics: insights from a South African estuary. Marine Pollution Bulletin, 186:114403
Ndhlovu A & von der Heyden S. (2022) De novo assembly and annotation of the transcriptome of the endangered seagrass Zostera capensis: insights from differential gene expression under thermal stress. Marine Genomics 66: 100984
van Wyk JW, Adams AB, von der Heyden S. (2022) Conservation implications of herbicides on seagrasses: sublethal glyphosate exposure decreases fitness in the endangered Zostera capensis. PeerJ, 10:e14295
Phair NL, Nielsen ES, von der Heyden S. (2021) Applying genomic data to seagrass conservation. Biodiversity and Conservation 30: 2079-2096
Phair NL, Toonen RJ, Knapp IS, von der Heyden S. (2020) Anthropogenic pressures negatively impact genomic diversity of the vulnerable seagrass Zostera capensis. (2020) Journal of Environmental Management 255: 109831