The current status of a Vulnerable seagrass, Halophila beccarii, on the Indian coast was reviewed using the published data from 1977 to 2020. It was observed that H. beccarii has a pan India ...distribution on both the east and the west coast of India. It is abundant in the intertidal silty-muddy region on the west coast and sandy and muddy habitats on the east coast. H. beccarii was found to be associated with mangroves or smaller seagrass species within a depth limit of 1.7m. Low salinity and high nitrate levels were observed at the H. beccarii meadows of the west coast due to their association with mangroves. The nutrient levels in H. beccarii meadows were comparatively lower than in the other seagrass meadows of India. Most of the research on H. beccarii has focussed on its morphometrics (22%), reproductive (22%), and bioactive compounds (18%) ecology along the coast of India. Reproductive traits such as flowering and fruiting vary according to the seasons of each coast due to the influence of monsoon and its associated changes in temperature, salinity, and nutrient influx. H. beccarii is a source of various bioactive compounds, which needs further investigation. Habitat disturbance, anthropogenic pollution, and coastal development are the three major causes for the decline of H. beccarii ecosystems in India. A significant loss of the seagrass was observed from the west coast of India due to increased coastal development activities. There is an acute need to quantify H. beccarii population trends, the impact of climate and anthropogenic stressors, economic values of ecosystem services, and the role of ecological connectivity for the better conservation and management of H. beccarii seascapes across India. There is a need for increased research and monitoring of seagrass meadows and the integration of research outcomes while framing policies in order to prevent further loss of this vulnerable seagrass.
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•H. beccarii has a distribution on both the east and west coast of India•Habitat disturbance is the major cause for the loss of H. beccarii population•There is a critical lack of data on the population trends of H. beccarii•Research on H. beccarii has declined after it was declared as Vulnerable•Increase in research and monitoring is essential to prevent further loss of H. beccarii
Microalgal-bacterial consortium is an effective way to meet increasingly stringent standards in wastewater treatment. However, the mechanism of wastewater removal effect has not been properly ...explained in community structure by phycosphere. And little is known about that the concept of macroecology was introduced into phycosphere to explain the phenomenon. In the study, the algal-bacterial consortia with different ratios of algae and sludge were cultured in same aerobic wastewater within 48 h in photobioreactors (PSBRs). Community structure at start and end was texted by metagenomic analysis. Bray-Curtis similarities analysis based on microbial community showed that there was obvious convergent succession in all consortia, which is well known as "convergence" in macroecology. The result showed that Bray-Curtis similarities at End (overall above 0.88) were higher than these at Start (almost less than 0.66). In terms of community structure, the consortium with 5:1 ratio at Start are the more similar with the consortia at End by which the maximum removal of total dissolved nitrogen (TDN, 73.69%), total dissolved phosphorus (TDP, 94.40%) and NH
-N (93.26%) in wastewater treatment process and biomass production (98.2%) higher than other consortia, according with climax community in macroecology with the highest resource utilization than other communities. Therefore, the macroecology can be introduced into phycosphere to explain the consortium for advanced wastewater treatment and optimization community structure. And the study revealed a novel insight into treatment effect and community structure of algal-bacterial consortia for advanced wastewater treatment, a new idea for to shortening the culture time of consortium and optimize predicting their ecological community structure and predicting ecological community.
Ascophyllum nodosum
is a large and common brown alga. The fronds are olive-brown but can appear yellowish when stressed. It is a common, intertidal species around the periphery of the North Atlantic ...Ocean. It is particularly common on the north-western coast of Europe (from Svalbard to Portugal), including east Greenland, Iceland and the NE coast of N America (from New York to Newfoundland). This intertidal fucoid has long fronds with large egg-shaped airbladders. The fronds can reach 2 m (extremes of 5–7 m) in length. Depending on nutrient availability, the fronds are yellow, and at low tide, they can form extensive beds appearing to be monospecific to the casual observer. This seaweed is long lived and can be a dominant, climax community species of the middle shore.
Ascophyllum nodosum
is very effective at accumulating nutrients and minerals from the surrounding seawater. Due to the presence of many bioactive components, its harvested biomass is a valuable resource for human enterprise. This species is exploited for use in products such as food, fertiliser, soil conditioners, biostimulants (for phyco-elicitors), animal feed, skin and hair care products, cleaners, de-greasers, equestrian products and nutritional supplements. It is also a popular ingredient in cosmetology and thalassotherapy.
Abstract
Successional theory proposes that fast growing and well dispersed opportunistic species are the first to occupy available space. However, these pioneering species have relatively short life ...cycles and are eventually outcompeted by species that tend to be longer-lived and have lower dispersal capabilities. Using Autonomous Reef Monitoring Structures (ARMS) as standardized habitats, we examine the assembly and stages of ecological succession among sponge species with distinctive life history traits and physiologies found on cryptic coral reef habitats of Kāneʻohe Bay, Hawaiʻi. Sponge recruitment was monitored bimonthly over 2 years on ARMS deployed within a natural coral reef habitat resembling the surrounding climax community and on ARMS placed in unestablished mesocosms receiving unfiltered seawater directly from the natural reef deployment site. Fast growing haplosclerid and calcareous sponges initially recruited to and dominated the mesocosm ARMS. In contrast, only slow growing long-lived species initially recruited to the reef ARMS, suggesting that despite available space, the stage of ecological succession in the surrounding habitat influences sponge community development in uninhabited space. Sponge composition and diversity between early summer and winter months within mesocosm ARMS shifted significantly as the initially recruited short-lived calcareous and haplosclerid species initially recruit and then died off. The particulate organic carbon contribution of dead sponge tissue from this high degree of competition-free community turnover suggests a possible new component to the sponge loop hypothesis which remains to be tested among these pioneering species. This source of detritus could be significant in early community development of young coastal habitats but less so on established coral reefs where the community is dominated by long-lived colonial sponges.
In temperate coastal environments, wide fluctuations of biotic and abiotic factors drive microbiome dynamics. To link recurrent ecological patterns with planktonic microbial communities, we analysed ...a monthly‐sampled 3‐year time series of 16S rRNA amplicon sequencing data, alongside environmental variables, collected at two stations in the northern Adriatic Sea. Time series multivariate analyses allowed us to identify three stable, mature communities (climaxes), whose recurrence was mainly driven by changes in photoperiod and temperature. Mixotrophs (e.g., Ca. Nitrosopumilus, SUP05 clade, and Marine Group II) thrived under oligotrophic, low‐light conditions, whereas copiotrophs (e.g., NS4 and NS5 clades) bloomed at higher temperatures and substrate availability. The early spring climax was characterised by a more diverse set of amplicon sequence variants, including copiotrophs associated with phytoplankton‐derived organic matter degradation, and photo‐auto/heterotrophic organisms (e.g., Synechococcus sp., Roseobacter clade), whose rhythmicity was linked to photoperiod lengthening. Through the identification of recurrent climax assemblages, we begin to delineate a typology of ecosystem based on microbiome composition and functionality, allowing for the intercomparison of microbial assemblages among different biomes, a still underachieved goal in the omics era.
Recurrent environmental patterns structure Mediterranean coastal microbial communities in climactic assemblages. Copiotrophic taxa (Rhodobacteraceae, NS4, NS5) associated with phytoplankton‐derived organic matter recur in spring; mixotrophs (Nitrosopumilus, SUP05, MGII) characterise vernal climax; summertime oligotrophic conditions favour Synechococcus domination among photoautotrophs and oligotypes exploiting organic matter.
In modern conditions of significant anthropogenic pressure on forests and global climate change, it is important to preserve primeval forests as centers of primary nature with the development of ...conceptual foundations for their conservation and functioning. The objects (sites) of investigation were located in the forest fund of the Verkhovynskyi National Nature Park, the territory of which is the most remote and difficult to access in the Ukrainian Carpathians. Five sample plots of 0.50 ha each were laid out in the spruce primeval forests. Within their boundaries, 125 tally areas were laid (25 in each sample plot) for accounting the young growth under the canopy of the spruce forests. In addition, 375 circular sample plots (three within each tally area) were laid for direct accounting of young growth by height groups. The trees were tallied in three categories: live standing trees; dead standing trees; down trees of the 1st stage of decomposition. The investigated 140-180-year-old primeval forests of Picea abies (L.) Karst. grow in the conditions of a high-altitude, pure fairly fertile spruce forest type at an altitude of 1,300-1,500 m above sea level. The stock of stemwood of live and dead standing trees was in the range of 423-709 m3∙ha-1 Provision of the spruce primeval forests with young growth at one object of investigation (Sample plot No. 3) was assessed as good (site class 1, 19.6 thousand pcs∙ha-1); at two objects (Sample plots No.1 and No.5) - as good (site class 2, 8.3 and 8.1 thousand pcs∙ha-1, respectively); at one site (Sample plot No.4) as satisfactory (6.9 thousand pcs∙ha-1); at one object (Sample plot No.2) as unsatisfactory (2.4 thousand pcs∙ha-1). Three of the investigated primeval forest communities (Sample plots No.1, No.2, and No.3) have reached the aging phase, two forest communities (Sample plots No.4 and No.5) have reached the breakdown phase. It is possible to tentatively generalize that the intensity of the process of natural renewal does not depend on the stage of the primeval forest development, but is determined by the density of the forest stand, the number of gaps in the canopy, and the development of the grass cover. The distribution of Picea abies young growth by height groups (10-39; 40-129; 130 cm and more) is, respectively, 56-66%; 27-41%; 3-16%. The young growth of Sorbus aucuparia L. occupies a small share in the total amount of young growth (up to 5%). About half of the rowan young growth is damaged by wild animals. The proportion of damaged spruce young growth is insignificant (less than 5%). The main cause is damage to the tops of young plants by falling fragments from dead standing trees or by the fall of the trees themselves. Spruce primeval forests have a well-developed grass cover, which is promoted by the uneven closure of tree crowns. Vaccinium myrtillus L. predominates, it occupies an average of 50-60% of the area of the investigated primeval forest communities (ranging from 30 to 70%). In addition to blueberries, there are Luzula sylvatica (Huds.) Gaudin, Athyrium filix-femina (L.) Roth, Ficaria verna Huds., Carex sylvatica Huds., Oxalis acetosella L. Grass cover is especially abundant within the clearings and gaps. In the spruce primeval forests, weak undergrowth development is observed, although the presence of gaps is characteristic of all the studied objects, which should have stimulated the undergrowth development. Ribes petraeum Wulfen, Lonicera nigra L. and Rosa canina L. are rarely found under the canopy of the spruce stands. The main cause is the high altitude above sea level, where the development of the undergrowth is limited by the climate. In general, the process of natural regeneration in the spruce primeval forests of the Verkhovynskyi NNP, which have reached the aging phase or the breakdown phase, is progressing satisfactorily. There are threats to the stable functioning of the primeval spruce forests of the Verkhovinskyi NNP: abiotic factors (climate changes, wind throws, snowfalls, windbreaks), biotic factors (damage by insects and pathogens), anthropogenic factors (atmospheric emissions, construction of a network of forest roads and tourist routes near areas with primeval forests, fires, etc.). Therefore, in order to preserve the unique primeval forest communities, there is a high expediency of including them in the list of spruce primeval forests of the Carpathians of the UNESCO World Heritage List.
A cal. 20-year-resolution pollen record from Gonghai Lake presented the detailed process of mountain vegetation succession and East Asian Summer Monsoon (EASM) changes since the last deglaciation in ...Shanxi Province, North China. Modern vegetation distribution and lake surface pollen assemblages suggested that the fossil pollen mainly came from local and surrounding vegetation in Gonghai Lake, which reflected the elevational changes of plant communities in study area. From 14,700 to 11,100 cal. yr BP, open forests and mountain meadows dominated by shrubs and herbaceous species in surrounding area, suggesting a weak EASM with less precipitation. In the period between 11,100 and 7300 cal. yr BP, bushwoods and grasses were gradually replaced by mixed broadleaf-conifer forest, first developed by pioneer species of Betula and Populus and then replaced by Picea, Pinus, and Quercus, implying an enhanced EASM and increased temperature and precipitation. During the period of 7300–5000 cal. yr BP, warm-fitted trees became expanded and widespread, indicating a climax community of mixed broadleaf-conifer forest and warm and humid climate with higher temperature and sufficient precipitation and the strongest period of EASM. From 5000 to 1600 cal. yr BP, Pinus pollen increased, but Quercus pollen decreased, showing the breakup of the climax community and the recession of the EASM. Since 1600 cal. yr BP, under the threats of land reclamation and deforestation, forest cover sharply decreased, and mountain grass lands were developed. The EASM changes inferred from pollen record of Gonghai Lake were asynchronous to the oxygen isotope records of stalagmites from southern China. We suggest that the existence of remnant Northern Hemisphere ice sheets and relative low sea levels might hampered the northward penetration of the EASM in early Holocene, which caused the maximum monsoon precipitation to reach northern China until mid-Holocene.
Canopy interception loss is an important hydrological process that affects rainfall redistribution, nutrient cycling, and soil and water conservation in forest ecosystems. However, the manner in ...which interception loss is affected in forests that are in restoration stages dominated by different tree species has not been fully understood. In this study, interception loss, throughfall, and stemflow were measured consecutively for 2 years (May 2017 through April 2019) in three secondary forests in subtropical China: a coniferous and broadleaved mixed forest (Pinus massoniana, Lithocarpus glaber, PM) in early restoration stage, a deciduous broadleaved forest (Choerospondias axillaris, CA) in middle restoration stage, and an evergreen broadleaved forest (L. glaber–Cyclobalanopsis glauca, LG) in late restoration stage. For a given amount of rainfall, the relative interception loss in the CA was significantly lower than that in the evergreen forests in summer, spring, or winter. The amount of interception loss during light rain, moderate rain, or heavy storms was also significantly lower in CA as compared to that in evergreen forests, owing to the lesser leaf area and phenology of deciduous tree species as well as a higher leaf area index (LAI) and stand density in PM and LG. Meanwhile, the highest relative interception loss, interception loss amount, canopy storage capacity, canopy cover fraction, and mean evaporation rate was observed in the climax forest (LG), which has a higher LAI and stand density. Further, the revised Gash's analytical model (RGAM) and the sparse Rutter models were successfully applied to simulate interception loss in these forests, with the RGAM performing better as compared to the sparse Rutter model. The results of the field measurements and model simulations depict that the climax community at the late restoration stage can effectively reduce the amount of rainwater reaching the soil surface, thus weakening the effect of flood peaks.
Highest interception loss occurred in climax forests at late restoration stage. Interception loss of light, moderate rain and heavy storms differed among forests. RGAM and sparse Rutter models were well fitted, with the RGAM performing better
In a natural ecosystem or as climatic climax community, grassland is relatively dry with a strongly seasonal climate, and sensitive to climatic changes. Most of the previous studies used remote ...sensing data to investigate the phenological response of grassland to climate change, while ground‐based studies covering a large geographic area were limited. In this study, using the long‐term phenological data (1981–2012) of 16 herbaceous species observed at 20 stations in Inner Mongolia, China, we first investigated the trends in three spring phenophases, including the dates of bud‐burst, first leaf unfolding, and 50% of leaf unfolding. Subsequently, multiple linear regressions between phenophases and four climatic factors (spring temperature, soil moisture, chilling temperature, and insolation) were performed to determine the relative importance of each factor on the spring phenology. To validate the resulted regression coefficients, we developed a controlled environment to investigate the factors regulating the leaf unfolding time of one dominant species (Leymus chinensis). The results showed that the study area became warmer and drier from 1981 to 2012. However, the overall changes in spring phenophases were not apparent, as there was a similar proportion of significant earlier or later trends. Such phenological changes were driven by multiple climatic factors. The warmer temperature would advance the spring phenophases, while lower soil moisture would delay them. The impact of soil moisture was significant in the experimental data, but not significant in the observation data. In addition, leaf unfolding became faster when L. chinensis experienced more chilling days, but this effect was difficult to be detected in observation data due to the weak sensitivity of the leaf unfolding time to chilling days. These findings can help us to understand how the spring phenology of typical herbaceous species responds to multiple climatic factors under the background of climate change.
The number of spring phenological time series of herbaceous plants with advanced or delayed trends at 20 stations in Inner Mongolia, China.
Wildfires, as an environmental filter, are pivotal ecological disturbances that reshape plant communities and soil dynamics, playing a crucial role in regulating biogeographic patterns and ecosystem ...services. In this study, we aim to explore the effects of wildfires on forest ecosystems, specifically focusing on the plant-soil feedback mechanisms within the northeastern margin of the Qinghai-Tibet Plateau (QTP). Utilizing Partial Least Squares Path Modeling (PLS-PM), we investigated the interrelationships among soil physicochemical properties, enzyme activities, species diversity, and community stability at varying post-fire recovery stages (5, 15, and 23 years). Results indicated that in the early recovery stages, rapid changes in soil properties such as decreased pH (p < 0.001) and increased nutrient availability facilitate the emergence of early successional species with high resource utilization traits. As the ecosystem evolved toward a climax community, the soil and vegetation exhibit increased stability. Furthermore, soil enzyme activities displayed dynamic patterns that corresponded with changes in soil nutrient content, directly influencing the regeneration and diversity of plant communities. Importantly, our study documented a transition in the influence of soil properties on community stability from direct positive effects in initial recovery phases to negative impacts in later stages, while indirect benefits accrue through increased species diversity and enzyme activity. Vegetation composition and structure changed dynamically with recovery time during community succession. Plant nutrient absorption and accumulation affected nutrient dynamics in the soil, influencing plant regeneration, distribution, and diversity. Our results underscore the complex interactions between soil and vegetation that drive the recovery dynamics post-wildfire, highlighting the resilience of forest ecosystems to fire disturbances. This study contributes to the understanding of post-fire recovery processes and offers valuable insights for the management and restoration of fire-affected forest ecosystems.
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