Adaptations and plastic phenotypic responses of marine animals to the environmental challenges of the high intertidal zone

The high intertidal zone is home to an incredible variety of marine animals, as it offers an escape from low intertidal/subtidal predation and competition, among other advantages. However, this area of the shore also comes with many tide-driven and emersion-associated environmental stressors, such as desiccation, high temperatures and freezing stress, hypoxia, salinity fluctuations, nitrogenous waste accumulation, ultraviolet (UV) radiation, wave and ice disturbance, and hydrogen sulphide (H2S) toxicity. This review explores the diversity of evolutionary adaptations and plastic phenotypic responses that high intertidal animals use to cope with these challenges. Examples are provided of behavioural, morphological, physiological and biochemical adaptations/responses, along with some of the underlying molecular mechanisms that have been elucidated to date. Adaptations of many different worms, anemones, molluscs, crustaceans and fishes are highlighted. Many adaptations and mechanisms of plasticity are universal among animal phyla, and some are multifunctional (serve more than one function) or provide tolerance to multiple stressors (i.e., ‘cross-tolerance’). High intertidal animals have received considerable attention by scientists, given their accessibility and that they can provide valuable insights in the transition from a marine to a terrestrial lifestyle. Nevertheless, further research is needed to understand the adaptations/responses of these animals more thoroughly, and the future holds great promise for accomplishing this with recent advances in epigenetics, transcriptomics, protein biochemistry and other molecular tools.

Study of Marine Sand-Dwelling Dinoflagellate With Four New Records From the Central South Coast of Viet Nam

In this study, marine sand samples were collected from the shallow intertidal zone of Nha Trang bay, Viet Nam. Taxonomic observations were conducted for the sanddwelling dinoflagellates using light, epifluorescent and scanning electron microscopy. Morphology characterizations of the four species namely, Amphidiniopsis hexagona, Thecadinium pseudokofoidii, Amphidinium herdmanii and Fukuyoa ruetzleri have been reported as new records for Vietnamese coastal waters. The genus Amphidiniopsis and Thecadinium are a new addition to the dinoflagellates flora of Viet Nam. Taxomomic descriptions and photographs of these species have been provided. Bangladesh J. Plant Taxon. 28(2): 367-378, 2021 (December)

Some data on the biology of stone cockscomb Alectrias alectrolophus (Stichaeidae) from the Tauysk Bay of the Sea of Okhotsk

On the basis of the materials collected in the period of 2010–2018 the features of biology: the size-age structure, linear growth pattern and body mass growth of the stone cockscomb Alectrias alectrolophus from the Tauysk Bay, the Sea of Okhotsk, have been studied. In the intertidal zone, in the period from May to September, individuals of this species the body length 31.2–133.4 mm and body weight 0.1–12.8 g at the age of up to 6+ years are found in large quantities. The size and age characteristics, rates of growth of females and males are quite similar, but in general, females are slightly larger than males.

MARINE HARDBOTTOM ENVIRONMENTS IN THE BEACHES OF CEARÁ STATE, EQUATORIAL COAST OF BRAZIL

This paper is a literature review on marine hardbottom environments (MHE) that emerge in coastal regions in the Brazilian state of Ceará. This stretch of the Brazilian coast houses several rock formations, which are widely distributed in the intertidal zone. These formations have various origins and composition, ranging from crystalline rocks to biogenic structures, but most are composed by sandstones. These substrates support biodiverse ecosystems that produce valuable environmental goods and services, which have historical and socioeconomic relevance for the state. Despite their importance, they are currently threatened by various types of local and global stressors, and a consistent government effort to protect them is still lacking. There are many knowledge gaps regarding these formations and new studies are needed to support conservation actions involving these ecosystems. Keywords: reef, beachrock, sandstone, intertidal zone, benthos

SPATIAL-TEMPORAL DISTRIBUTION OF POLYCHAETA IN URBANIZED SANDY BEACHES OF NORTHEASTERN BRAZIL: TOOLS FOR ENVIRONMENTAL ASSESSMENT

In the last years, the use of Polychaeta as indicators of marine pollution has intensified, due to the sensitivity of these organisms to environmental variations and their significant presence in quantitative and qualitative terms when compared to other benthic fauna organisms. We aimed to analyze the Polychaeta assemblage of two urbanized beaches in São Luís – Maranhão (Brazil), focusing on spatial-temporal distribution and look for the relation of the species sampled and possible contamination to indicate if they are suitable for environmental assessment. Sediment collection was carried out in the intertidal zone of both beaches in dry (September and November/2015) and rainy periods (March and May/2016). The samples were screened for extraction of the species, which were classified at the lowest possible taxonomic level. The samples revealed the following taxa: Lumbrineridae (Scoletoma tetraura), Nereididae (Laeonereis culveri) and Spionidae (Scolelepis sp.). The diversity and abundance of Polychaeta were greater on Caolho Beach. On these beaches, organic enrichment is not the determining variable in the structure of the Polychaeta assembly. Other studies are needed to improve the knowledge on other macrofauna species of the studied areas, comparing the richness among microhabitats and seasons, and thus elaborate conservation strategies for these ecosystems; and to test the hypothesis of the influence of tourism on this assemblage.

Towards human and nature reconciliation: a Māori worldview approach to ecological landscape architecture.

<p>This research explores how applying Māori worldview principles can reconcile and allow mutualism between people and ecologies within the post industrial urban setting of Wellington wharf. The aim of this thesis is to develop three possible solutions to reconcile people with ecologies and allow for mutual benefits within natural ecologies of the intertidal zone below Wellington wharf. This research explores how a nonconventional ecological approach that includes human interaction in restorative landscape design can create beneficial interactions between humans and microorganisms.</p>

Towards human and nature reconciliation: a Māori worldview approach to ecological landscape architecture.

<p>This research explores how applying Māori worldview principles can reconcile and allow mutualism between people and ecologies within the post industrial urban setting of Wellington wharf. The aim of this thesis is to develop three possible solutions to reconcile people with ecologies and allow for mutual benefits within natural ecologies of the intertidal zone below Wellington wharf. This research explores how a nonconventional ecological approach that includes human interaction in restorative landscape design can create beneficial interactions between humans and microorganisms.</p>

Foraging ecology of the amphibious mudskipper Periophthalmus chrysospilos (Gobiiformes: Gobiidae)

The food composition and feeding ecology of fishes living in the intertidal zone play an essential role in understanding the energetic connectivity between terrestrial and aquatic systems. Periophthalmus chrysospilos is an amphibious fish species occurring in the intertidal zone, but data on its diet and foraging ecology is still poorly known. This study on Ps. chrysospilos was carried out from April 2020 to March 2021 at four sites within the Mekong Delta estuary to define the influence of spatio-temporal factors on the diet of this species. The diet composition and relative gut lengths (RGLs) of Ps. chrysospilos were analysed in relation to four parameters—sex, size, site, and season. A total of 1,031 individuals were collected, and their digestive tract lengths were used to calculate the RGL. The digestive tracts of only 546 individuals were with food items (approximately 1:1 of empty vs full digestive tract) and were subsequently used for further analyses. The ranges in total length and weight in both adult and juvenile individuals were 3.4–10.6 cm and 0.38–14.13 g, respectively. The RGL values varied with season, fish size and site, but was always lower than 1, indicating a predominantly carnivorous diet. The variability of food items found within the digestive tracts demonstrated its adaptability in pursuing prey items within the limits of the littoral zone, and its importance as a conduit of terrestrial-marine connectivity. This species is characterised as an opportunistic mesopredator feeding primarily on Acetes spp., Uca spp., Dolichoderus sp., and rarely on Polychaeta and Actinopterygii. Other items found within the digestive tract are Mollusca, and detritus. The diet composition of Ps. chrysospilos did not vary with season and size, but changed with sex and site parameters. Uca spp. contributed to the sexual variation in dietary component, whereas Mollusca, Uca spp., Dolichoderus sp. and detritus, were drivers for spatial variation in the dietary component. The research provides fundamental information on diet composition and feeding strategy, as well as contributes towards knowledge on foraging ecology and resource use by intertidal animal communities.

Correlation And Dispersion Of Marine Debris To Mollusca In The Interidal Zone

The research was carried out on Langgur Beach from January to March 2021. The purpose of this study was to determine the correlation and dispersion of marine debris to molluscs in the Intertidal Zone of Langgur Beach, the edge of the Rosenberg Strait, Kei Islands, Indonesia. The data collection method of this research is the quadratic method. The results of the study noted that the total marine debris accumulated at 21 sampling points amounted to 7,596 items consisting of 14 categories of marine debris and 6 species of Mollusca were found. The results of the analysis show that the dispersion of surface marine debris and marine debris in the sediments are scattered in groups, the dispersion per type of macrozoobenthos on the surface and in the sediments is scattered in groups, regularly and randomly. The results of the analysis also showed a positive correlation between marine plastic debris on the sediment surface and the bivalves of Gafrarium pectinatum on the sediment surface.