Hydrology, vegetation, and soil properties as key drivers of soil organic carbon in coastal wetlands: A high-resolution study.

Coastal wetlands are important blue carbon ecosystems that play a significant role in the global carbon cycle. However, there is insufficient understanding of the variations in soil organic carbon (SOC) stocks and the mechanisms driving these ecosystems. Here we analyze a comprehensive multi-source dataset of SOC in topsoil (0-20 cm) and subsoil (20-100 cm) across 31 coastal wetlands in China to identify the factors influencing their distribution. Structural equation models (SEMs) reveal that hydrology has the greatest overall effect on SOC in both soil layers, followed by vegetation, soil properties, and climate. Notably, the mechanisms driving SOC density differ between the two layers. In topsoil, vegetation type and productivity directly impact carbon density as primary sources of carbon input, while hydrology, primarily through seawater salinity, exerts the largest indirect influence. Conversely, in subsoil, hydrology has the strongest direct effect on SOC, with seawater salinity also influencing SOC indirectly through soil and vegetation mediation. Soil properties, particularly pH, negatively affect carbon accumulation, while climate influences SOC indirectly via its effects on vegetation and soil, with a diminishing impact at greater depths. Using Random Forest, we generate high-resolution maps (90 m × 90 m) of topsoil and subsoil carbon density (R 2 of 0.53 and 0.62, respectively), providing the most detailed spatial distribution of SOC in Chinese coastal wetlands to date. Based on these maps, we estimate that SOC storage to a depth of 1 m in Chinese coastal wetlands totals 74.58 ± 3.85 Tg C, with subsoil carbon storage being 2.5 times greater than that in topsoil. These findings provide important insights into mechanism on driving spatial pattern of blue carbon and effective ways to assess carbon status on a national scale, thus contributing to the advancement of global blue carbon monitoring and management.

Spatio-temporal composition of aquatic birds communityin Juluapan Lagoon, Colima, Mexican Central Pacific / Composición espacio-temporal de las aves acuáticas en la laguna Juluapan, Colima, en el Pacífico Central Mexicano

Abstract Introduction: Aquatic birds (AB) are usually associated with wetlands, which provide refuge, food, and/or nesting sites for resident and migratory species. Despite their ecological importance, there is little knowledge on AB in some tropical environments, such as those found on the Colima coast. Objective: To investigate the spatial and temporal composition of the AB community in Juluapan Lagoon, Colima, Central Mexican Pacific. Methods: Monthly counts were conducted between June 2017 and May 2018 during low-tide conditions to record habitat use by AB. Species richness and bird counts were obtained to compare sampling areas; mean richness and number of individuals were compared between seasons. Results: We detected 53 species and 5 750 individuals. The highest species richness and relative abundance values were obtained in winter at the lagoon area farthest from the connection with the marine system, where anthropogenic activity is lower. Diversity was greater in zones 2 and 3 in spring, summer, and fall. Muddy flats were the most used environment, and the most frequent activity was resting. Nesting activity was only recorded in the middle of the lagoon at the mangrove during spring. "Shorebirds" and "waders" were the most dominant groups in the bird community of the Juluapan lagoon. Conclusions: This coastal wetland is a site of great biological importance for aquatic birds; thus, conservation measures should be implemented, and there should be a continuous study of the effects of anthropogenic pressure.

Resumen Introducción: Las aves acuáticas (AA) son usualmente relacionadas a los humedales debido a que éstos funcionan como sitios de refugio, alimentación y anidación de diferentes especies residentes y migratorias. Sin embargo, el conocimiento sobre las aves acuáticas en algunos humedales es nulo. Objetivo: Investigar la composición espacio-temporal de la comunidad de AA en la laguna Juluapan, Colima, en el Pacífico Central Mexicano. Métodos: Entre junio de 2017 y mayo de 2018 se llevaron a cabo conteos mensuales en condiciones de marea baja para registrar el uso de hábitat de las AA. Se obtuvieron valores de riqueza de especies y número de individuos para realizar comparaciones entre zonas de muestreo, así como el promedio del número de especies y número de individuos para comparaciones entre temporadas. Resultados: Se registraron un total de 53 especies y 5 750 individuos. Los valores de riqueza de especies y densidad de individuos fueron más altos durante invierno, en la zona más alejada al ambiente marino, donde la actividad antropogénica es menor. La diversidad tuvo valores más altos en la zona 2 y 3, durante primavera, verano y otoño. El ambiente más explotado por las aves fueron las planicies lodosas; y el descanso fue la actividad más frecuente. Asimismo, la actividad de anidación sólo se registró en el manglar de la zona media durante primavera. Las "aves playeras" y "aves zancudas" fueron los grupos más predominantes en la comunidad de aves de la laguna Juluapan. Conclusiones: Este humedal costero es un sitio de gran importancia biológica para aves acuáticas, por lo que resulta necesario la implementación de medidas de conservación, así como el estudio de los efectos por la presión antropogénica.

A high-resolution spatiotemporal morphological dataset: Port Aransas beach, Texas.

The study of beach morphology holds significant importance in coastal management, offering insights into coastal and environmental processes. It involves analyzing physical characteristics and beach features such as profile shape, slope, sediment composition, and grain size, as well as changes in elevation due to both erosion and accretion over time. Furthermore, studying changes in beach morphology is essential in predicting and monitoring coastal inundation events, especially in the context of rising sea levels and subsidence in some areas. However, having access to high-frequency oblique imagery and beach elevation datasets to document and confirm coastal forcing events and understand their impact on beach morphology is a notable challenge. This paper describes a one-year dataset comprising bi-monthly topographic surveys and imagery collected daily at 30 min increments at the beach adjacent to Horace Caldwell Pier in Port Aransas, Texas. The data collection started in February 2023 and ended in January 2024. The dataset includes 18 topographic surveys, 6879 beach images, and ocean/wave videos that can be combined with colocated National Oceanic and Atmospheric Administration metocean measurements. The one-year temporal span of the dataset allows for the observation and analysis of seasonal variations, contributing to a deeper understanding of coastal dynamics in the study area. Furthermore, a study that combines survey measurements with camera imagery is rare and provides valuable information on conditions before, after, and between surveys and periods of inundation. The imagery enables monitoring of inundation events, while the topographic surveys facilitate the analysis of their impact on beach morphology, including beach erosion and accretion. Various products, including beach profiles, contours, slope maps, triangular irregular networks, and digital elevation models, were derived from the topographic dataset, allowing in depth analysis of beach morphology. Additionally, the dataset contains a time series of four wet/dry shoreline delineations per day and their corresponding elevation extracted by combining the imagery with the digital elevation models. Thus, this paper provides a high-frequency morphological dataset and a machine learning-ready dataset suitable for predicting coastal inundation.

Unveiling drivers of conservation agriculture amidst climate challenges: A coastal Bangladeshi case study.

Conservation agriculture practices play a pivotal role in augmenting agricultural productivity while concurrently fostering biodiversity, mitigating soil erosion, and enhancing plant nutrition. This study aims to delve into the determinants influencing the adoption behavior of farmers regarding conservation agriculture practices, categorizing them into medium adoption, less adoption, and non-adoption groups. Primary data were meticulously gathered from three distinct regions within the coastal areas of Bangladesh, encompassing a total of 450 respondents. Descriptive statistics were employed to delineate the socio-economic status of farmers, while multinomial logistic regression was utilized to identify factors affecting conservation agriculture adoption. This study also employed to find out the severity of different climate problem faced by the farmers. Analysis of organizational communication patterns revealed that medium adopters maintained a more substantial connection with diverse organizations compared to other groups. Descriptive statistics elucidated that both medium and less adopters of conservation agriculture had undergone more training, possessed higher farm incomes, and exhibited greater levels of education compared to non-adopters. Further exploration through factor analysis unveiled that increased training significantly influenced farmers' decisions to embrace conservation agriculture practices, concurrently enhancing their knowledge of agricultural methodologies. The study identified positive relationships between crop income, cultivable land, different channel communication exposure, climate change perception and training duration with the adoption of conservation agriculture. Finally, the results underscore the importance of organizational monitoring systems and frequent farmer engagement, alongside an augmentation in training initiatives. These measures are posited to yield more favorable outcomes in promoting conservation agriculture practices among farmers. Alongside, Conservation agriculture play a key role for achieving sustainable land use and climate action.

Plant diversity value of informal green spaces in tropical coastal urban areas: An empirical study of species, functional, and phylogenetic diversity.

Informal green spaces (IGS) are a hot topic in urban biodiversity studies, but overlooked in urban biodiversity conservation or management, especially in tropical coastal cities, where comprehensive assessments remain scarce. Most existing research has been limited to species diversity (α-diversity), with few studies addressing phylogenetic, functional, and species turnover (ß-diversity) across multiple IGS types. This study bridges these gaps by conducting a detailed vegetation survey in Jiangdong New Area of Haikou City, establishing 213 sites. Within these sites, we examined 343 IGS sample plots and 274 formal green spaces (FGS) sample plots. We assessed species, functional, and phylogenetic diversity using α and ß diversity metrics and analyzed the influence of environmental factors with generalized linear mixed models (GLMMs). The results recorded 235 species of herbaceous plants from 179 genera and 54 families in IGS, including 215 spontaneous species, compared to 154 spontaneous species in FGS. Our findings indicate that IGS exhibited higher species richness and functional richness compared to FGS, though differences in phylogenetic diversity were less pronounced. Key environmental factors like relative humidity, trampling intensity, and proximity to urban areas significantly influenced species richness and abundance in IGS. These findings underscore the critical role of IGS in enhancing biodiversity and resilience in tropical coastal cities, emphasizing the need to integrate IGS into urban planning strategies for sustainable urban ecosystems.

Ecological Effects of the Huge Invasive Species Removal Project in Coastal China.

Saltmarsh wetlands are recognized as some of the most ecologically valuable yet vulnerable ecosystems globally. However, since the 1970s, saltmarsh wetlands in coastal China have been seriously threatened by the invasive Spartina alterniflora. Although the Chinese government has initiated a nationwide S. alterniflora removal project, the potential benefits and risks of this project remain unknown. Here, we focus on the Yangtze River Estuary Saltmarsh Wetland (YRESW) and simulate its future ecosystem structure, function, and quality under three scenarios based on remote sensing and field investigation data. The simulation scenarios include the absence of a removal project, natural regeneration postproject (NRP), and planted restoration postproject. The results show that the removal project will reverse the escalating invasion trend of S. alterniflora in the YRESW. Compared to the baseline year of 2022, there is a remarkable increase in ecosystem structure (composition: +107%, configuration: +27%) and ecosystem quality (+10.5%) under the NRP scenario. Although blue carbon storage sharply decreases under both scenarios involving project implementation, planted restoration can restore YRESW's carbon sequestration capacity to 0.19 Tg C per year, achieving 87% of the carbon storage present before the project. This study underscores the necessity of comprehensive and detailed risk assessments in ecological projects, particularly when dominant species are involved. Our findings hold significant implications for stabilizing coastal wetland ecosystems and promoting sustainable development in coastal areas.

Microbial responses on upwelling signature across reversal wind pattern in tropical coastal environment off Mumbai, India.

Upwelling promotes marine productivity through water column mixing. The process disturbs the ecosystem, causing oxygen depletion and thermal variability. This study analyses effect of upwelling processes on microbial signature in coastal waters off Mumbai. The coastal environment with seasonal reversal winds was analysed using data during ten cruises. Coastal metocean processes are examined using water quality parameters and the Ekman approximation with wind stress. This analysis explains oxygen depletion and coastal upwelling, influenced by seasonal reversal wind pattern. The study connects hypoxia in the coastal water column to wind-induced upwelling. Concurrently, microbial structure is assessed through metrics such as Total Viable Count, Total Bacterial Count, Sulfate Reducing Bacteria (SRB), and denitrifiers. Notably, high levels of SRB are observed during hypoxia associated with coastal upwelling. This study investigates microbial level with combined result of physical processes and water quality parameters.

In Dabouki Land: Interdisciplinary notes on the cultural history of a landrace grape cultivar in Israel.

Cultivated for millennia, the grapevine held a special status as one of the most important fruits in the historical Levant and the Mediterranean world. However, since past farmers typically did not leave written accounts of their activities, viticulture history is often shrouded in ambiguity, especially concerning the classification of grapevine landrace varieties. Hence, the study of archaic viticulture relies heavily on methodological fusion to unravel its more readily discernible biological and oral traditions. We therefore merged archaeological fieldwork, historical archival analysis, field geography and ethnographic interviews to collect multifarious data on the Dabouki grapevine. Our analytical synthesis enabled us to depict how, over the course of history, diverse communities variously grew this cultivar in dryland vineyards. The cultural history of the Dabouki stretches from at least the Ottoman era, when it was widely planted throughout the region under various names, to its current revival by enterprising Israeli and Palestinian winemakers. The majority of our research was conducted within a unique environmental corridor in the western Negev of Israel where dense concentrations of relic Dabouki grapevine survive. Our paper surveys the cultural history of the Dabouki grape as a flagship cultivar in the intergenerational horticultural regimes of arid land farmers in the western Negev of the southern Levant. Remarkably, archaic Negev viticulturalists used the same cultivars across successive historical periods and varying socioeconomic contexts. As such, the paper illustrates that arid regions with longstanding winegrowing traditions are ideal for locating endemic grapevines that apparently can withstand challenging growing conditions. Focusing on the enduring legacy of the Dabouki, we suggest how historical knowledge of ancient dryland farming systems and landrace cultivars can bolster the sustainability of contemporary viticulture.

Microbial ocean-atmosphere transfer: The influence of sewage discharge into coastal waters on bioaerosols from an urban beach in the subtropical Atlantic.

All over the world, the oceans are the final destination of sewage transported by river estuaries, rainwater and other coastal discharges. The risks to human health related to direct contact with water and consumption of contaminated fish are well known, but little is known about the potential for atmospheric exposure to pollutants and pathogens from contaminated seawater. The release of microbial particles from the sea into the atmosphere occurs mainly by the eruption of rising bubbles through the sea surface microlayer (SML) or by sea spray. We investigated the heterotrophic bacteria density and relative abundance in SML and bioaerosols originated on the seafront of Fortaleza (Atlantic coastal zone, northeastern Brazil) influenced by wastewater disposal. There was a difference in the density of total heterotrophic bacteria (THB) according to the matrix analyzed during two seasons: the bacterial count was highest in the SML during the rainy season while the highest number of bacteria in bioaerosols samples was recorded during the dry season. Twenty-nine bacterial taxonomic groups were identified with variable abundance for both environments. These were the same in both matrices, with environmental variables influencing their abundance and composition. The contribution of the marine and continental environments in shaping the microbiota of the SML and coastal bioaerosols was clear, with the constant and representative presence of Enterobacteria standing out. The aerosolization of bacteria resulting from the discharge of untreated sewage is an important issue related to coastal environmental health and ecological safety.

Soil carbon pools and microbial network stability depletion associated with wetland conversion into aquaculture ponds in Southeast China.

Wetlands, which are ecosystems with the highest soil surface carbon density, have been severely degraded and replaced by artificial reclamation for fish and shrimp ponds in recent years. This transformation is causing intricate shifts in soil carbon pools and microbial stability. In this study, we examined natural wetlands and reclaimed aquaculture ponds in Southeast China to analyze the structure and network stability of soil microbial communities following the reclamation of estuarine wetlands and to elucidate the microbial-mediated mechanisms for regulating soil organic carbon (SOC). The aquaculture ponds presented significantly less average SOC content than the natural wetlands (p < 0.05). ACE, Chao1, and Shannon's indices of bacteria and fungi were decreased in aquaculture ponds. Less numbers of nodes and edge links in the co-occurrence network of soil fungi and bacteria in aquaculture ponds. This suggests reduced correlation and stability within the microbial network of aquaculture ponds. Decomposers in soil fungi (e.g. Dung Saprotroph) reduced. Reduced proportions of key phyla Ascomycota, Basidiomycota and Rozellomycota in the soil fungal network. Reduced proportions of key phyla Proteobacteria, Chloroflexi and Desulfobacterota in the soil bacterial network. In conclusion, our results suggest that converting wetland paddocks to intensive aquaculture ponds results in carbon pool loss and reduces soil microbial network stability. The results highlight the importance of protecting or moderately restoring mangrove wetlands along the coast of southeastern China. It is also predicted that such measures may enhance the storage capacity of soil carbon pools and improve the stability of carbon sequestration by soil microorganisms, thus offering a potential solution for mitigating global climate change.

Temporal enrichment of comammox Nitrospira and Ca. Nitrosocosmicus in a coastal plastisphere.

Plastic marine debris is known to harbor a unique microbiome (termed the "plastisphere") that can be important in marine biogeochemical cycles. However, the temporal dynamics in the plastisphere and their implications for marine biogeochemistry remain poorly understood. Here, we characterized the temporal dynamics of nitrifying communities in the plastisphere of plastic ropes exposed to a mangrove intertidal zone. The 39-month colonization experiment revealed that the relative abundances of Nitrospira and Candidatus Nitrosocosmicus representatives increased over time according to 16S rRNA gene amplicon sequencing analysis. The relative abundances of amoA genes in metagenomes implied that comammox Nitrospira were the dominant ammonia oxidizers in the plastisphere, and their dominance increased over time. The relative abundances of two metagenome-assembled genomes of comammox Nitrospira also increased with time and positively correlated with extracellular polymeric substances content of the plastisphere but negatively correlated with NH4+ concentration in seawater, indicating the long-term succession of these two parameters significantly influenced the ammonia-oxidizing community in the coastal plastisphere. At the end of the colonization experiment, the plastisphere exhibited high nitrification activity, leading to the release of N2O (2.52 ng N2O N g-1) in a 3-day nitrification experiment. The predicted relative contribution of comammox Nitrospira to N2O production (17.9%) was higher than that of ammonia-oxidizing bacteria (4.8%) but lower than that of ammonia-oxidizing archaea (21.4%). These results provide evidence that from a long-term perspective, some coastal plastispheres will become dominated by comammox Nitrospira and thereby act as hotspots of ammonia oxidation and N2O production.

Biofilm-mediated interactions between plastics and radiocesium in coastal environments.

A ubiquitous distribution of plastic debris has been reported in aquatic and terrestrial environments; however, the interactions between plastics and radionuclides and the radioactivity of environmental plastics remain largely unknown. Here, we characterize biofilms developing on the surface of plastic debris to explore the role of plastic-associated biofilms as an interaction medium between plastics and radiocesium (137Cs) in the environment. Biofilm samples were extracted from plastics (1-50 mm in size) collected from two contrasting coastal areas in Japan. The radioactivity of plastics was estimated based on the 137Cs activity concentration of the biofilms and compared seasonally with surrounding environmental samples (i.e., sediment and sand). 137Cs traces were detected in biofilms with activity concentrations of 21-1300 Bq·kg-1 biofilm (dry weight), corresponding to 0.04-4.5 Bq·kg-1 plastic (dry weight). Our results reveal the interaction between 137Cs and plastics and provide evidence that organic and mineral components in biofilms are essential in 137Cs retention in environmental plastics. Given the ubiquitous distribution of plastic debris in the environment, more attention should be directed to bioaccumulation and the radioecological impacts of plastic-associated radionuclides on ecosystems.

Dataset on the variability of the light field in coastal waters.

The authors present data on both inherent and apparent optical properties, CTD profiles for the southwestern area of the Bay of Cartagena (Colombia) along a transect of seven stations. The data were collected during the dry and wet seasons of 2022. Optical properties include the depth of the Secchi disk as well as the absorption coefficients of particulate organic matter (ap) and chromophoric dissolved organic matter (aCDOM), together with analyses of total suspended solids (TSS) and turbidity in terms of nephelometric units (NTU). The dataset encompasses several types of data files on the light field in water, which is suitable for the development of water quality indices, the study of optically complex systems occupied by strategic marine ecosystems, the input of the calibration and validation processes of satellite algorithms as well as coastal zone management and administration.

Navigating the sea level rise: Exploring the interplay of climate change, sea level rise, and coastal communities in india.

This research article investigates the intricate interplay between climate change, global sea level rise (SLR), and the impacts of sea level rise on the coastal regions of India. Through an interdisciplinary approach, this paper provides an overview of the global consequences of SLR on coastal communities, exploring economic, social, and environmental impacts on agriculture, communities, and coastal areas. The study examines the displacement of communities and its impact on food security, infrastructure, tourism, and ecological loss based on a comprehensive literature review. This paper emphasizes the sustainable preservation of coastal ecosystems and the development of climate-resilient infrastructure. This research aims to offer a detailed understanding of the evolving landscape of coastal livelihoods, providing valuable insights for adaptive strategies, policy formulation, and sustainable development. Ultimately, this article contributes to the scientific discourse by shedding light on the complex dynamics between climate change, SLR, and coastal communities, guiding efforts toward a resilient and sustainable future. The insights are drawn from secondary data resources, including books, scholarly journals, and reports from organizations such as the IPCC and NOAA. Based on a thorough review of the relevant literature, it critically examines the existing and potential consequences of sea level rise induced by climate change.

A novel multi-hazard risk assessment framework for coastal cities under climate change.

Coastal cities, as centres of human habitation, economic activity and biodiversity, are confronting the ever-escalating challenges posed by climate change. In this work, a novel Multi-Hazard Risk Assessment framework is presented with the focus on Coastal City Living Labs. The methodology provides a comprehensive assessment of climate-related hazards, including sea-level rise, coastal flooding, coastal erosion, land flooding, heavy precipitation, extreme temperatures, heatwaves, cold spells, landslides and strong winds. Its application is illustrated through a case study: the Coastal City Living Lab of Benidorm, Spain. The methodology incorporates remote sensing data from various satellite sources, such as ERA5, Urban Atlas and MERIT DEM, to evaluate multiple hazards through a systematic and standardized indicator-based approach, offering a holistic risk profile that allows for comparison with other European coastal cities. The integration of remote sensing data enhances the accuracy and resolution of hazard indicators, providing detailed insights into the spatiotemporal dynamics of climate risks. The incorporation of local expertise through the Coastal City Living Lab concept enriches data collection and ensures context-specific adequacy. The integration of local studies and historical extreme climate events enhances the validity and context of the risk indicators. The findings align with regional trends and reveal specific vulnerabilities, particularly related to heatwaves, heavy rainfall, and coastal flooding. Despite its strengths, the MHRA methodology faces limitations, including reliance on outdated datasets and the complexity of integrating multiple hazards. Continuous updates and adaptive management strategies are essential to maintain the accuracy and relevance of risk assessments. The broader implications of the methodology for global coastal cities highlight its potential as a model for developing targeted adaptation strategies.

Identifying toxic elements in water, sediments, and roots of mangrove forest (Avicennia marina) in Chabahar Bay, Sea of Oman.

Mangroves play a crucial role in filtering pollutants from water and sediments. However, excessive accumulation of potentially toxic elements (PTEs) has harmful effects on marine organisms. This article investigates the concentration and distribution of PTEs in water, sediment, and the roots of endangered mangrove species in Chabahar Bay, a subtropical coastal wetland. The relationship between PTE absorption and accumulation rates with flow rate, mangrove extent, and sedimentation was also explored. Water, sediments, and aerial roots samples were taken at four stations along the wetland from upstream fresh water toward outfall. According to the results, Cd had more distribution in sediment and water samples and plants did not play as adsorbent in the study area. The lowest and highest PTEs concentrations were detected in water and sediment media, respectively. The average concentrations of PTEs in the sediments in the Chabahar Bay were Fe > Cr > Zn > Ni > Cu > Pb > Co > As > Cd while in aerial roots of the mangroves were Fe > Zn > Ni > Cr > Cu > Co > As > Pb > Cd. Except Zn, As, and Cd, there was a good correlation between increasing PTEs content in the sediments with decreasing flow velocity and increasing vegetation density along stations 3 to 4. In addition, the amount of PTEs uptake by the mangroves was less than that of global wetlands. The results also demonstrated a greater uptake in aerial roots in saline water for Cr, Ni and Co. Since the absorption rate of PTEs by the aerial roots of pneumatophores is slower than that in sediments, elevated concentrations of PTEs in the sediment can disrupt the entire ecosystem, leading to a potential decline in biodiversity. These toxins can enter the food chain, affecting not only organisms directly interacting with the sediment but also higher trophic levels, such as fish and birds.

C/N ratio effect on oily wastewater treatment using column type SBR: machine learning prediction and metagenomics study.

The sequencing batch reactor has emerged as a promising technology in treating wastewater; however, its application in the treatment of generated water still needs to be explored. This research gap led to the investigation of various carbon-to-nitrogen (C/N) ratios in a column-type sequencing batch reactor (cSBR). The resulting data and model demonstrated that augmenting the SND process with an external carbon source is effective until the C/N ratio reaches 15, ultimately eliminating nitrogen in the produced water. Conversely, a reduced C/N ratio can limit the ability of polyphosphate-accumulating organisms to incorporate carbon into polyphosphate synthesis, thereby decreasing phosphorus removal efficiency within the cSBR. When the C/N ratio ranged from 6 to 8, and the mixed liquor suspended solids concentration was high, the average phosphate removal was approximately 55%, compared to only around 25% when the C/N ratio was less than 6.

Soil greenhouse gas fluxes partially reduce the net gains in carbon sequestration in mangroves of the Brazilian Amazon.

There is interest in assessing the potential climate mitigation benefit of coastal wetlands based on the balance between their greenhouse gas (GHG) emissions and carbon sequestration. Here we investigated soil GHG fluxes (CO2 and CH4) on mangroves of the Brazilian Amazon coast, and across common land use impacts including shrimp farms and a pasture. We found greater methane fluxes near the Amazon River mouth (1439 to 3312 µg C m-2 h-1), which on average are equivalent to 37% of mangrove C sequestration in the region. Soil CO2 fluxes were predominant in mangrove forests to the East of the Amazon Delta. Land use change shifted mangroves from C sinks (mean sequestration of 12.2 ± 1.4 Mg CO2e ha-1 yr-1) to net GHG sources (mean loss of 8.0 ± 3.3 Mg CO2e ha-1 yr-1). Our data suggests that mangrove forests in the Amazon can aid decreasing the net annual emissions in the Brazilian forest sector in 9.7 ± 0.8 Tg CO2e yr-1 through forest conservation and avoided deforestation.

Adaptive capability of slow-growing backyard poultry as indicated by physiological and molecular responses in a hot and humid coastal climate.

Assessing the adaptability of slow-growing rural chickens for improving thermotolerance to suit the global climate change is a major research need. This work was aimed to evaluate the adaptability of CARI-Debendra chickens and to identify the polymorphism as well as expression profiling of thermotolerant genes (HSP70 and GRP78) under prevailing temperature-humidity indices and thermal stress in a coastal environment. One hundred sixty straight run chicks were reared at THI≥75 (control) and THI>80 under coastal climate till 12 weeks. Polymorphism of HSP70 and GRP78 candidate genes were explored using restriction enzymes TaqI and HaeIII to identify possible thermotolerance markers. Expression profiling of both the genes in liver, intestine and pectoralis muscle was determined through quantitative real-time PCR. Rectal and body surface temperature recorded in the neck and back showed significant differences (P < 0.01) with higher temperature in THI>80 group. Comparatively lower live weights (P < 0.05) and poor FCR were recorded in THI>80 group. The villi height in all intestinal segments was significantly lower (P < 0.01), but deeper crypt depth was observed in THI>80 than control group. A lowest thymus weight (P < 0.05) was noted with no significant differences in immune response in treatment group. Serum levels of cholesterol, activities of lactate dehydrogenase, creatinine kinase and concentration of potassium, sodium and thyroxine hormone were not different between the 2 groups. The concentration of triiodothyronine and chloride ion was lower in THI>80 group indicating adaptive changes for thermoregulation. HSP70 gene expressions in the three tissues were differentially increased (P < 0.01) by temperature-humidity indices, but the expression of GRP78 was not different between the 2 groups. The results concluded that the environmental factors interact with genetics on adaptability towards thermotolerance in slow-growing chickens.