Pond Soil Research Articles

The existing conditions of distribution parameters of physical and chemical factors of salt pond land on the Coast of Palang District, Tuban Regency, Indonesia

The purpose of this study was to determine the distribution value of physical and chemical factors that affect salt pond land. We employed a method to assess the current state of salt ponds in coastal regions. We conducted this study in Palang District, Tuban Regency, from May 1 to June 1, 2024. This research method involves various methods, including remote sensing and geographic information systems (GIS), to map and analyze land conditions. We will use data from satellite imagery and field measurements to evaluate the physical and chemical parameters for the development of salt ponds. Based on the research data, we have established that the physical and chemical parameters of salt pond land on the coast of Palang District, such as salt table height, seeding place, main embankment, intermediate embankment, pH, and pond bottom, are in good condition and meet the requirements for salt pond land development. In conclusion, the chemical parameters show that the quality of water and soil in salt ponds is still within acceptable limits, although there are several locations that show values approaching the standard quality threshold. We recommend implementing sustainable management practices in the development of salt ponds, which include periodic monitoring of physical and chemical parameters, further research on the impacts of climate change, and collaboration between government, academics, and communities in managing sustainable salt ponds and formulating policies that support the development of the salt industry in coastal areas.

Effect of Different Plant Growth Regulators on Seed Germination, Seedling Growth and Establishment of Papaya (Carica papaya L.) c.v. Taiwan-7

An experiment was conducted at the Department of Horticulture, Sam Higginbottom University of Agriculture, Technology & Sciences, Prayagraj (U.P)-211007, India during year 2023-24. The experiment was laid out in Randomized Design (RBD). There were Ten treatments including control replicated three times in which growing media such as pond soil, vermicompost, and Plant growth regulators mixed in various percentages. The different levels of plant growth regulators Such as GA3, NAA and BA with different compositions in different combinations showed positive responses on the physical quality attributes of the papaya plant. The maximum values of physical quality characteristics of papaya plant like Survival percentage (90.68) number of germination days (10.01), germination percentage (90.01), number of leaves (10.46), plant height (12.76 cm), leaf area (38.4 cm2) and chlorophyll content (52.84), Number of primary roots (10.46), number of secondary roots(27.68) and stem diameter (3.85 cm) were recorded in T3 (GA3 with 150 ppm) and followed by the treatment T6 (NAA with 150 ppm) while, minimum values of these characters maximum value of physical parameter was recorded in control treatment (T0). From the present investigation it is concluded that treatment (T3) Performed best in terms of growth parameters followed by (T6) and (T9). The maximum B:C ratio (2.02) was also observed in the same treatment i.e. (T3).

Differences in shrimp pond bottom soil properties and bacterial load between acute hepatopancreatic necrosis disease (AHPND)‐infected ponds and AHPND‐free ponds and their relation to AHPND

AbstractThis study investigated the disparities in soil characteristics and pathogenic bacteria prevalence between shrimp ponds affected by acute hepatopancreatic necrosis disease (AHPND) and unaffected ponds, alongside examining the spatial distribution of soil attributes in flat‐oriented pond soil strata. Using Pearson correlation and logistic regression analyses, relationships among variables and indicators associated with AHPND prevalence were discerned, leading to the formulation of a predictive model for AHPND occurrence. Soil samples were collected from distinct locations and depths within ponds across three southern provinces of Thailand's Andaman Seaboard. The analysis revealed significantly higher concentrations of several variables, including SOD, TIC, NO2−‐N, Ca, Mn, Cu, Zn, and specified Vibrio strains, in AHPND‐afflicted ponds, especially at 0–5 cm depth. A prominent differentiation was the escalated concentration of easily decomposable organic matter (EDOM) within infected ponds, implicating potential soil and water quality deterioration alongside heightened shrimp susceptibility to AHPND. Correlational analysis showed links between bacterial densities and organic matter groupings, trace elements, exchangeable bases, and soil pH, in AHPND‐infected ponds. The logistic regression model encapsulated three soil variables (TOC, Mg, and Mn) and one pathogen variable (V. parahaemolyticus) and furnished an equation to estimate the log (odds) of AHPND occurrence, facilitating better understanding and potential forecasting of AHPND prevalence in shrimp cultivation environments.

Vegetation Loss Following Vertical Drowning of Mississippi River Deltaic Wetlands Leads to Faster Microbial Decomposition and Decreases in Soil Carbon

AbstractWetland ecosystems hold nearly a third of the global soil carbon pool, but as wetlands rapidly disappear the fate of this stored soil carbon is unclear. The aim of this study was to quantify and then link potential rates of microbial decomposition after vertical drowning of vegetated tidal marshes in coastal Louisiana to known drivers of anaerobic decomposition altered by vegetation loss. Profiles of potential CH4 and CO2 production (surface to 60 cm deep) were measured during anaerobic incubations, organic matter chemistry was assessed with infrared spectroscopy, and soil porewater nutrients and redox potentials were measured in the field along a chronosequence of wetland loss. After vertical drowning, pond soils had lower redox potentials, higher pH values, lower soil carbon and nitrogen concentrations, lower lignin: polysaccharide ratios, more NH4+ and PO43−, and higher rates of potential CO2 release than vegetated marsh soils. Potential CH4 production was similar in vegetated marshes and open water ponds, with depth‐dependent decreases in CH4 production as soil carbon concentrations increased. In these anoxic soils, vegetation loss exerts a primary control on decomposition rates because flooding drives sustained increases in porewater nutrient availability (NH4+ and PO43, dissolved organic carbon) and decreases in redox potential (from −150 to −500 mV) that lead to higher potential CO2 fluxes within a few years. Without new carbon inputs following wetland loss, the sustained decomposition in open water ponds may lead to losses of stored soil carbon and could influence global carbon budgets.

Identification of soil properties influencing primary productivity of fish ponds under red and lateritic soil zones

Aim: The present study aimed to identify the key soil factors influencing the primary productivity of water in the fish ponds situated under low productive red and lateritic soil zones. Methodology: General properties of fish pond soils (n=42) from different red and lateritic soil zones of West Bengal, India were determined along with the gross primary productivity (GPP) values of corresponding pond waters. All the soil properties were correlated with GPP values and the soil factors which were significantly correlated with GPP of pond water were further used for step down regression analysis with regard to GPP.This helped to develop a minimum data set of the key soil factors which showed maximum influence on GPP. The efficiency of the regression equation, generated with the critical soil parameters, in predicting the GPP values of other ponds was also assessed through a study on the variations in calculated and on-farm GPP values of eight fish ponds. Results: Among all the studied soil properties, pH and availability of three major nutrients viz. N, P and K were observed to contribute 84.15% variations in gross production of primary fish food organisms in these pond environment. Of these 4 soil properties, again, pH and available P values of the pond soils appeared to be more important. A regression equation was also developed to predict the GPP of such pond water using soil pH and available P values only. This equation showed a precision range of 83.0 to 99.7% and was found to be statistically at par with the GPP values observed under actual pond condition. Interpretation: High efficiency in predictability of pond GPP values using the minimum data set of two key soil factors viz. soil pH and available P indicates that proper management of these productivity attributing soil properties will be particularly helpful to improve the primary productivity levels of the predominantly low yielding fish ponds under the red and lateritic soil zones. Key words: Fish ponds, Minimum data set, Productivity attributes, Red and lateritic soil zones, Soil factors

Provenance studies on ancient mud mortars, plasters, and floor soils of India’s Raigad hill fort

Understanding the building materials and construction practices employed is an inevitable component of forensic studies on ancient structures. In Particular, knowing the origins of the raw materials used in manufacturing native building materials is vital for preparing new materials that are compatible with ancient materials for their restoration. The present work focused on establishing the provenance of raw materials used in the construction of the Raigad hill fort, dated between the 12th and 17th centuries. This study particularly carries significance due to the fact that the fort is located at a height of 800m above sea level with no lime source on the hilltop. It is believed the builders of Raigad hill fort predominantly used local soils in the creation of mud plasters and mud mortars. However, validation of this supposition is necessary prior to the selection of raw materials for preparing the building material for the retrofitting works. Hence, the present study investigates the mud plasters, mud mortars, and floor soils of the fort, along with soil samples collected from Ganga Sagar Pond on the hilltop. The physical and compositional analytical characterization techniques such as sieving (for Particle size analysis), Elemental analyzer (for CHNS determination), XRD (for mineralogical characterization), FTIR, SEM-EDS, and TGA/DTA (for thermal analysis) were performed on the collected mud plaster, mud mortar and soil samples. Based on the physical–chemical-mineralogical data, it is revealed that the local pond soil was sourced for the preparation of mud plaster and mortar, and its properties were modified by adding basaltic aggregates and organic additives to the extent of 13–17%.

Detection of Metabolic Gene of Interest (MGOI) in WGS of Microbacterium barkeri (LMA4)

This communication reports about detection of metabolically active genes of interest cell free extract of actinomycetal isolates from Pond soil. The strain LMA4 previously identified as Microbacterium barkeri, based on biotyping as well as 16 s r RNA sequencing, was observed with moderate bioactivity against test strains of Staphylococcus aureus and Escherichia coli. The Actinomycetal strain was Gram positive, aerial profuse branching bearing rounded spores. The whole genome sequencing was carried using Next Generation Sequencing tools and techniques. The FASTA sequence received from sequencing farm had been subjected to BLASTn analysis and aligned with sequences of databse. The sequence similarity was checked considering percentage of identity, as inferred from online portal. The whole genome sequence of LMA4 had inferred about elution of antibiotic producing genes namely [i] Thiazole synthase protein, [ii] Indole-3-glycerol phosphate synthase Protein, [iii] Antibiotic synthesis MbtH protein, [iv] Antibiotic biosynthesis monooxygenase protein, [v] class II terpene cyclase protein and [vi] YcaO-like family protein in the sequence profile. The genes were identified, ORFs were predicted and more over conserved domain was spotted. The genes were structurally represented using modelling approaches and more so ligand based (target oriented) molecular simulation study had predicted affirmative interactions between receptor and ligand molecule. The receptors were WGS detected gene products, and the ligands were Sortase of Staphylococcus aureus and D-ala-ala ligase of Escherichia coli. The study may pave a way towards extracting the metabolites of interest and implementing as natural cost effective drugs.

Mechanisms of microbial-driven changes in soil ecological stoichiometry around gold mines

In this study, we used soils with different pollution and nutrient levels (non-polluted S1, highly polluted low-nutrient S2, and highly polluted high nutrient S3) around the gold mine tailing ponds, and combined with metabolic limitation modeling and macro-genomics approaches, aiming to investigate the relationship between soil microbial composition and soil eco-chemometrics characteristics under heavy metal stress. The results showed that heavy pollution resulted in reduced SOC, TN, microbial biomass, and with C- and P- acquisition (BG, CBH, ALP) as well as nitrogen limitation of soil microbial metabolism in soils (S2, S3). Further analysis by macrogenomics showed that heavy metal contamination led to an increase in α-microbial diversity and altered the composition of microbial communities in the soil. The cycling of C, N, and P nutrients was altered by affecting the relative abundance of Anaeromyxobacter, Steroidobacter, Bradyrhizobium, Acidobacterium, Limnochorda (predominantly in the Ascomycetes and Acidobacteria phyla), with the most pronounced effect on the composition of microorganisms synthesizing C-acquiring enzymes, and heavy metals and pH were the main influences on ecological stoichiometry. The results of this study are useful for understanding the sustainability of ecological remediation in heavy metal contaminated areas and for developing ecological restoration strategies.

Effect of Washing and Non-washing of Seeds on Growth of Papaya Seedlings (Carica papaya L.) cv. Pusa Nanha

The present experiment was carried out to investigate the response of washing and non- washing of seeds on growth of papaya seedling at the CRC Farm, ITM University, Gwalior (M.P.). The experiment was set up in the Randomized Block Design using 4 media with or without washing of seeds with tap water comprising 12 treatments combinations (viz., controlled (soil + water), vermiwash (50%) + wood dust, vermiwash (50%) + cocopeat, vermiwash (50%) + pond soil, cow-urine (50%) + wood dust, cow-urine (50%) + cocopeat, cow-urine (50%) + pond soil, vermiwash (100%) + wood dust, vermiwash (100%) + cocopeat, vermiwash (100%) + pond soil, cow-urine (100%) + wood dust, cow-urine (100%) + cocopeat, cow-urine (100%) + pond soil which were replicated thrice. For experimental purpose, freshly ripe fruits of papaya were purchased from the papaya-growing farmer of IARI, New Delhi and seeds were sown in the poly bag (4x24 inch sized). The results indicated that the application of application of Vermiwash (100%) + pond soil recorded maximum height of seedling (cm), number of leaves per seedling, stem diameter (cm), leaf area (158.41 cm2), fresh weight of seedling (8.49g), dry weight of seedling (1.17 g), dry weight of shoot (0.334g), dry weight of root (0.779), root/shoot ratio (2.34) as compared to without washing of seeds and other rooting media. Thus, application of Vermiwash (100%) + pond soil was found to the best treatment among all the treatments and it gave the maximum growth attributes which will inturn improve the yield of papaya.

Effect of Washing and Non-Washing of Seeds on Germination of Papaya Seedling (Carica papaya L.) cv. Pusa Nanha

A field experiment was conducted to investigate the response of washing and non- washing of seeds on germination of papaya seedling at the CRC Farm, ITM University, Gwalior (M.P.). The experiment was laid out in the Randomized Block Design using 4 media with or without washing of seeds with tap water comprising 12 treatments combinations (viz., controlled (soil + water), vermiwash (50%) + wood dust, vermiwash (50%) + cocopeat, vermiwash (50%) + pond soil, cow-urine (50%) + wood dust, cow-urine (50%) + cocopeat, cow-urine (50%) + pond soil, vermiwash (100%) + wood dust, vermiwash (100%) + cocopeat, vermiwash (100%) + pond soil, cow-urine (100%) + wood dust, cow-urine (100%) + cocopeat, cow-urine (100%) + pond soil which were replicated thrice. For experimental purpose, freshly ripe fruits of papaya were purchased from the papaya-growing farmer of IARI, New Delhi and seeds were sown in the poly bag (4x24 inch sized). The results indicated that the application of Vermiwash (100%) + pond soil recorded minimum days (6.78) required for initiation to germination, minimum days (9.22) required for 50 per cent germination while maximum (100.00) germination percentage in papaya seedlings. Thus, washing of papaya seedlings with vermiwash +pond soil will increase the germination and in turn the production of papaya.

Physico-chemical Features of Water and Soil in Rural Fish Ponds and its Relationship with Pond Productivity

Samples of water and soil were collected at. monthly and bimonthly intervals, respectively from four different rural fish ponds of Bhadrak District, Orissa for three years (1994-1997) and were subjected to analysis for different physicochemical parameters. The values obtained for different parameters were subjected to analysis of variance and multiple correlation to establish the interrelationship of some important hydrobiological parameters. The parameters like pH, dissolved oxygen, nitrate-nitrogen, phosphate-phosphorus and organic carbon were positively correlated to the plankton production which influences the productivity of the fish ponds.

Content and Composition of Organic Matter in Some Sewage-Treated Fish Pond Soils in Relation to Productivity

The organic matter content and its composition in relation to primary productivity of soil in 12 sewage-treated fish ponds were studied. Organic carbon contents of the soils were fairly high, ranging between 1.02 and 3.85%. The amount of humus carbon, on an average, constituted 23.7% of the total organic carbon. The carbon content of humic and fulvic acids of the soils ranged from 0.066 to 0.222 and 0.210 to 0.560%, respectively, constituting, on an average, 27.7 and 72.3%, respectively, of the total humus carbon. Primary productivity of the pond was found to be significantly correlated with total organic carbon, humus carbon, and humic acid and fulvic acid carbon contents of the soils.

Inversion of soil heavy metals in metal tailings area based on different spectral transformation and modeling methods

The exploitation of mineral resources has seriously polluted the environment around mines, notably in terms of heavy metal contamination of tailings pond soil. Hyperspectral remote sensing, as opposed to conventional on-site sampling and laboratory analysis, offers a potent tool for effective monitoring the content of soil heavy metals. Therefore, we investigated the inversion models of heavy metal content in metal tailings area based on measured hyperspectral and multispectral data. Hyperspectral and its transformation, as well as the simulated Landsat8-OLI multispectral were used for model inversion respectively. Stepwise Multiple Linear Regression (SMLR), Partial Least Squares Regression (PLSR) and Back Propagation Neuron Network (BPNN) were established to study the spectral inversion of eight heavy metals (Cu, Cd, Cr, Ni, Pb, Zn, As, and Hg). The direct inversion models were established on the basis of correlation analysis and the adjust coefficient of determination (Adjust_R2) and Root Mean Square Error (RMSE) were used for model evaluation. Then the best combination of spectral transformation and inversion model were explored. The model inversion results suggested that: (1) Hyperspectral transformation can generally improve the model accuracy, especially the second derivative spectral, based on which the training Adjust_R2 of Hg SMLR and PLSR models are as high as 0.795 and 0.802. (2) The BP neural network inversion based on the denoised hyperspectrum demonstrate that both the training and testing Adjust_R2 of Cd, Ni and Hg models are all greater than 0.5, indicating good applicability in practical extrapolation. (3) Both the training and testing Adjust_R2 of Cu and Hg PLSR models based on simulated R_Landsat8-OLI multispectral are greater than 0.5, and Hg has lower RMSE and lager Adjust_R2 with training and testing Adjust_R2 values of 0.833 and 0.553 respectively. (4) Multispectral remote sensing detection and mapping of Hg contamination were realized by the optimal simulation model of Hg. Hence, it is feasible to simulate the multispectral with hyperspectral data for investigating heavy metal contamination.

Xylan derived carbon dots composite with PCL/PLA for construction biomass nanofiber membrane used as fluorescence sensor for detection Cu2+ in real samples

Water and soil pollution caused by Cu2+ is not conducive to sustainable development of environment and could cause damage to environment and even human body. Currently, fluorescent sensor solutions analysis method has been used for Cu2+ detection, but they also suffer from drawbacks including easy leakage, difficult storage, and inaccurate. Herein, a green solid-state biomass fluorescence platform (NBU-CDs) consisting of xylan-derived carbon dots (U-CDs) and polylactic acid/polycaprolactone (PLA/PCL) was designed by using in situ electrospinning technology. The prepared NBU-CDs fluorescence platform showed good fluorescence effect and can be served as fluorescence sensor for detecting Cu2+ with high sensitively, selectively and low detection limit (LOD = 0.83 μM). The practical applications of NBU-CDs exhibited high specificity for Cu2+ detection in zebrafish, water samples (school lake, Xuanwu Lake and Yangtze River) with high recovery rates of 97 %–104 % and soil (pond soil, grassland soil and bamboo soil) samples, respectively. The developed fluorescence platform was utilized to predict water and soil safety by monitoring Cu2+ concentration and provides a new strategy for Cu2+ detection.

Water and soil studies in Shrimp aquaculture systems

Litopeneaus vannamei is the most preferable species for culture by shrimp producers due to short time crop, hardy species and high market value. Present investigation was carried out to comprehend the significance of the carbon and nitrogen ratio in shrimp farming systems at Ankola, Uttara Kannada (District) and Haleyangadi, Mangaluru (Taluk) and Dakshina kannada (District). The pond water characteristics namely temperature, pH, alkalinity, salinity, Dissolved oxygen, biological oxygen demand, total suspended solids, total dissolved solids, Ammonia, NO2, NO3, PO4, SiO3 were found to vary from 28 to 35°C, 6.9 to 9.4, 25 to 125 mg/l, 0 to 36 ppt, 0 to 4.20mg/l, 0.020 to 0.259mg/l, 1.63 to 81.24mg/l, 0.12 to 36.45μg at./l as micro-mole per liter, 0.09 to 11.12 μg at./l, 0.26 to 32.15μg at./1, 0.15 to 26.18μg at./l, 2.40 to 90.18μg at./l respectively. The pond soil characteristics comprising of pH, organic carbon were ranged from 6.5 to 8.6, 0.235 to 1.994%, respectively while texture comprising of sand content varied from 48.41 to 96.26%, clay 0.3 to 2.45% and silt 3.14 to 51.24%. C/N ratio is varied 1.084-11.450 during the research phase. The outcomes of the water quality parameters shown quite higher nutrient all selected ponds and Organic carbon showed high in all ponds along with day of culture that’s impact data on water quality and influence on pond biomass and the C/N ratio. A culture system's ability to produce more can be greatly increased by maintaining the quality of the soil and water by removing toxicity though nitrification and continuous monitoring.

Environmental Parameters Determine the Structure of Soil Bacteria under Different Land use Types in Tailings Area

Soil microorganisms contribute substantially to a wide range of services and thereby improve recovery in ecosystem restoration. However, there is relatively limited information on how microbial communities respond to different land-use types with similar plant species and their potential roles in supporting soil restoration in mine tailings. To understand the importance of the response of soil microbial communities to the stress of tailings area in different soil habitats, this article selected three different land use types (Tailings area, Buffer zone and Vegetable field) as the variables in the Yanzibian tailings area in Ningqiang, Shaanxi Province, China. Soil physicochemical properties and heavy metal concentrations of the different land use types were compared. Illumina MiSeq. 2500 Sequencing Technology was used to analyze the abundance and structural diversity of the microbial community in soil samples. The results showed that most of the soil samples were unsafe with multiple metals. All soil samples in the buffer zone and tailings ponds were acidic. With the acidity decreased, bacterial community richness and diversity increased significantly. Briefly, different environmental factors and soil microbial communities were significantly distinct across different land-use types. Cu, Zn, Pb, pH, MC (Moisture content), TN (Total nitrogen), TP (Total phosphorus), and TK (Total potassium) were essential factors affecting the abundance and structural diversity of soil microbial communities across three different land-use types. As a result, Actinobacteria, Alphaproteobacteria, and Gammaproteobacteria were the top dominant classes in the buffer zone and Vegetable field soils, while Sulfobacillia dominated in tailings pond soils. Further, we found that with the continuous decline of the pH, the dominant genera transferred from norank_f__norank_o__Vicinamibacterales, Bacillus and Nocardioides to the norank_f__norank_o__Gaiellales and norank_f__norank_o__Acidobacteriales, then to Sulfobacillus. These confirmed that the responses of microbiota to heavy metals stress varied in different land-use types. Together, this study provides important information on the occurrence and distribution of soil microbiomes in tailings areas and their potentially beneficial roles in soil restoration.

Lime application to condition soil to pH 11 controls growth of harmful vibrios and WSSV

Shrimp farming has been devastated by several diseases. Disease outbreaks can be prevented by optimising environmental conditions or by eliminating risks factors including carrier organisms. These can be achieved through proper pond preparation. One important step in pond preparation is the application of hydrated lime. This paper describes the effect of hydrated lime application to condition pond soil to pH 11 on the pond ecosystem, more specifically on soil pH and biota. The experiment was done using three 600 m2 brackish water ponds. After hydrated lime application, the wet soil pH on the 1st-8th day was significantly higher (P<0.05) compared to the pH before liming to pH 11, and flushing after flooding for 24 h. Soil pH of 11 was observed 24-48h after lime application. Moreover, unwanted species like crabs and fish were found dead. Liming to pH 11 negatively affects the counts of green vibrio colonies thereby decreasing the percentage of green vibrios (PGV). In another experiment, three 750m2 earthen ponds were used. The pond soils were previously positive for the Whitespot Syndrome Virus (WSSV), hydrated lime were applied to bring the pond soil pH to 11. After lime application, WSSV was not detected in the pond soils. Results showed that increasing the soil pH to ≥11 positively affects the pond ecosystem. Liming encourages the proliferation of yellow vibrios and the eradication of carrier species (i.e. crabs) as well as predators (i.e. fish) in the ponds. Furthermore, liming to pH 11 may also eradicate White spot virus from the pond sediment. To implement a 1-unit increase in wet pH, hydrated lime should be applied at 2T/ha.

APLIKASI HIDROGEN PEROKSIDA DI SEDIMEN TERHADAP KUALITAS AIR DAN PERTUMBUHAN UDANG VANAME Litopenaeus vannamei

Pond bottom sediment conditions influence shrimp culture. As benthic organisms, shrimp are mainly on the surface of the pond bottom, so cultivation preparations related to improving sediment quality are essential. Pond bottom practice, such as drying, liming, and fertilizing, is common. However, in bottom pond conditions where total drying cannot be carried out, other treatments are needed, such as the addition of hydrogen peroxide. The purpose of this study was to determine the effect of adding hydrogen peroxide in pond sediments on the performance of shrimp growth and water quality. The study was conducted with five doses of hydrogen peroxide (0.25 mL, 0.5 mL, 1 mL, 2 mL) mixed with 350 g of pond soil sediment. Ten shrimps with an average weight of 0,27±0,03 g were put into the rearing container, which had been given pond bottom sediment according to the treatment. The results showed that the 2 mL hydrogen peroxide treatment gave the best results on the growth rate and average weight of Pacific whiteleg shrimp at the end of rearing. Water quality such as pH value, dissolved oxygen, and temperature were not significantly different between treatments. Hydrogen peroxide treatment can improve shrimp growth performance without affecting water quality during rearing.

Streptomyces beihaiensis sp. nov., a chitin-degrading actinobacterium, isolated from shrimp pond soil.

A Gram-stain-positive actinobacterium, designated strain GXMU-J5T, was isolated from a sample of shrimp pond soil collected in Tieshangang Saltern, Beihai, PR China. The morphological, chemotaxonomic and phylogenetic characteristics were consistent with its classification in the genus Streptomyces. The organism formed an extensively branched substrate mycelium, with abundant aerial hyphae that differentiated into spores. Phylogenetic analysis of 16S rRNA gene sequences showed that strain GXMU-J5T was most related to Streptomyces kunmingensis DSM 41681T (similarity 97.74 %) and Streptomyces endophyticus YIM 65594T (similarity 96.80 %). However, the values of digital DNA-DNA hybridization, average nucleotide identity and evolutionary distance of multilocus sequence analysis between strain GXMU-J5T and its closest relatives indicated that it represented a distinct species. Strain GXMU-J5T contained ll-diaminopimelic acid and the major whole-cell hydrolysates were xylose and galactose. The predominant menaquinones of strain GXMU-J5T were revealed as MK-9(H4), MK-9(H6) and MK-9(H8). The polar lipids consisted of diphosphatidylglycerol, phosphatidylmethylethanolamine, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol mannosides and phospholipids of unknown structure containing glucosamine. The predominant cellular fatty acids were iso-C15 : 0, anteiso-C15 : 0, iso-C16 : 0, iso-C17 : 0 and anteiso-C17 : 0. The whole genome size of strain GXMU-J5T was 6.79 Mbp with a 71.39 mol% G+C content. Genomic analysis indicated that strain GXMU-J5T had the potential to degrade chitin. On the basis of these genotypic and phenotypic data, it is supported that strain GXMU-J5T represents a novel species of the genus Streptomyces, for which the name Streptomyces beihaiensis sp. nov. is proposed. The type strain is strain GXMU-J5T (=MCCC 1K08064T=JCM 35629T).

Probiotic BioPlus® PS modulate shrimp-tilapia polyculture pond soil microbiome and exhibit bioremediation potential

ABSTRACT The study evaluated the effects of the probiotic BioPlus® PS on shrimp-tilapia polyculture pond soil using an integrated approach of physical-chemical analysis, metagenomics, and Pfeiffer circular chromatography. Soil was collected from a shrimp farm immediately after harvest and distributed in 75 plastic boxes with a useful volume of 1 L. The probiotic was applied once at the following doses in triplicate: 0, 150, 300, 1000 and 2000 g ha−1. After fifteen days, we verified a significant reduction in the content of organic matter, oxidizable carbon and potential acidity. Metagenomics demonstrated that the probiotic increased α diversity, while decreasing the relative abundance of Vibrio parahaemolyticus. Pfeiffer chromatography showed that the two samples that received higher doses showed characteristics associated with higher quality soils and higher enzymatic activity. Our results suggest that the application of the probiotic BioPlus® PS in shrimp pond soils has bioremediation potential and can positively modulate the soil microbiome.