scholarly journals Composition of microbial PLFAs and correlations with topsoil characteristics in the rare active travertine spring-fed fen

2016 ◽  
Vol 35 (4) ◽  
pp. 295-308 ◽  
Author(s):  
Peter Hanajík ◽  
Milan Zvarík ◽  
Hannu Fritze ◽  
Ivan Šimkovic ◽  
Róbert Kanka

Abstract We studied soil PLFAs composition and specific soil properties among transect of small-scale fen in Stankovany, Slovakia. The aim of this study was to determine potential differences in the microbial community structure of the fen transect and reveal correlations among PLFAs and specific soil characteristics. PCA analyses of 43 PLFAs showed a separation of the samples along the axis largely influenced by i14:0, 16:1ω5, br17:0, 10Me16:0, cy17:0, cy17:1, br18:0 and 10Me17:0. We measured a high correlation of sample scores and distance from fen edge (Kendall’s test τ = 0.857, P < 0.01). Kendall’s test showed a negative correlation of PLFAs content (mol%) and distance from the fen border for Gram (+) bacteria, Actinomycetes, mid-chain branched saturated PLFAs and total PLFAs. The redundancy analysis of the PLFA data set for the eight samples using PLFAs as species and 21 environmental variables identified soil properties significantly associated with the PLFA variables, as tested by Monte Carlo permutation showing most significant environmental variables including dichlormethan extractables, water extractables, Klason lignin, acid-soluble lignin, holocellulose, total extractables, organic matter content, total PLFA amount, bacterial PLFA and total nitrogen negatively correlated to axis 1 and dry weight and carbonate carbon positively correlated to axis 1. The amounts of Klason lignin, acid-soluble lignin, holocellulose total extractables, total PLFA, bacterial PLFA and total nitrogen were significantly correlated positively to the distance from fen border while moisture and total carbonate carbon were correlated negatively.

2012 ◽  
Vol 610-613 ◽  
pp. 3500-3504 ◽  
Author(s):  
Wei Wang ◽  
Gui Hua Yang ◽  
Jia Chuan Chen

Fast-growing Poplar cooked by Soda-AQ process was studied, by determining the lignin contents including Klason lignin and acid soluble lignin, the yield of pulping, the rate of carbohydtare degradation and the rate of delignification.Results indicated that the delignificaton of Fast-growing Poplar in Soda-AQ pulping can be divided into three distinguishable stages. (a)The initial delignification stage before 140°C,the rate of delignification reaches to 30.87%;(b)The bulk delignification stage, the rate of delignification reaches to 86.97%,in the period from 140°C to 170°C and for 30 min;(c)The residual delignification stage,the rate of delignification exceeds 91.60%. The defibration point was reached when cooking temperature raised to 170°C and for 30 min with 57.50% pulping yield ,24.94 kappa nomber.


2012 ◽  
Vol 560-561 ◽  
pp. 682-687
Author(s):  
Yu Cui ◽  
Jia Chuan Chen ◽  
Gui Hua Yang

The process of kraft pulping of Fast-growing Poplar was studied,by determining the lignin contents including Klason lignin and acid soluble lignin, the yield of pulping, the rate of carbohydtare degradation and delignification rate. Results indicated that the delignificaton of Fast-growing Poplar in kraft pulping can be divided into three distinguishable stages. (a)The initial delignification stage before 140°C,the rate of delignification reaches to 35.76%; (b)The bulk delignification stage, the rate of delignification reaches to 90.50%,in the period from 140°C to 170°C and for 30 min; (c)The residual delignification stage,the rate of delignification exceeds 95.56%. The defibration point was reached when cooking temperature raised to 170°C and for 30 min with 52.22% pulping yield ,17.83 kappa number.


2021 ◽  
Vol 503 (2) ◽  
pp. 2688-2705
Author(s):  
C Doux ◽  
E Baxter ◽  
P Lemos ◽  
C Chang ◽  
A Alarcon ◽  
...  

ABSTRACT Beyond ΛCDM, physics or systematic errors may cause subsets of a cosmological data set to appear inconsistent when analysed assuming ΛCDM. We present an application of internal consistency tests to measurements from the Dark Energy Survey Year 1 (DES Y1) joint probes analysis. Our analysis relies on computing the posterior predictive distribution (PPD) for these data under the assumption of ΛCDM. We find that the DES Y1 data have an acceptable goodness of fit to ΛCDM, with a probability of finding a worse fit by random chance of p = 0.046. Using numerical PPD tests, supplemented by graphical checks, we show that most of the data vector appears completely consistent with expectations, although we observe a small tension between large- and small-scale measurements. A small part (roughly 1.5 per cent) of the data vector shows an unusually large departure from expectations; excluding this part of the data has negligible impact on cosmological constraints, but does significantly improve the p-value to 0.10. The methodology developed here will be applied to test the consistency of DES Year 3 joint probes data sets.


2021 ◽  
Author(s):  
Sandeep Mishra ◽  
Kunwar D Yadav

Abstract For in-vessel composting of garden waste, the selection of reactor is an important factor for efficient degradation. The present study evaluates working performance of rotary drum reactor (RDR) and aerated in-vessel (AIV) for composting of garden waste. 100 kg garden waste was mixed with 10 kg cow-dung slurry and 5 kg compost and feed into both the reactors for 45 days composting period. The reactors vary in their system configuration, shape and orientation, blade design, rate of aeration, odour control, leachate production and energy requirements. Rotary drum was rotated daily six times in clockwise and anti-clockwise direction and AIV was rotated daily for 3–5 minutes using motor. Rise in temperature started within 24 hours of composting and reached 65°C and 59°C on second day itself and thermophilic phase continued for 7 and 5 days for RDR and AIV respectively. Moisture content reduction after composting period was 15.25 and 18.45 %, C/N ratio was 16.14 and 13.33, TVS reduction was 23.74 and 29.78 % and CO2 evolution rate was 6.18 and 4.14 mg/g VS/day in RDR and AIV respectively. Reduction of hemicellulose, cellulose, and lignin was more in AIV. The percentage reduction of acid insoluble lignin was 36.10 and 29.01 % and the percentage reduction of acid soluble lignin was 48.85 and 43.3% in in AIV and RDR respectively after 45 days. AIV gave better performance for composting of garden waste.


2008 ◽  
Vol 310 (1-2) ◽  
pp. 103-112 ◽  
Author(s):  
Zhiyong Zhou ◽  
Osbert Jianxin Sun ◽  
Zhongkui Luo ◽  
Hongmei Jin ◽  
Quansheng Chen ◽  
...  

2015 ◽  
Vol 12 (2) ◽  
pp. 34-38 ◽  
Author(s):  
Ashim Kumar Saha ◽  
Apu Biswas ◽  
Abdul Qayyum Khan ◽  
Md. Mohashin Farazi ◽  
Md. Habibur Rahman

Long-term tea cultivation has led to degradation of the soil. Old tea soils require rehabilitation for restoring soil health. Soil rehabilitation by growing different green crops can break the chain of monoculture of tea. An experiment was conducted at The Bangladesh Tea Research Institute (BTRI) Farm during 2008-2011 to find out the efficiency of different green crops on the improvement of soil properties. Four green crops such as Guatemala, Citronella, Mimosa and Calopogonium were grown to develop the nutritional value of the degraded tea soil. Soil samples were collected and analyzed before and at the end of experiment. Soil pH was increased in all four green crops treated plots with the highest increase in Citronella treated plots (from 4.1 to 4.5). Highest content of organic carbon (1.19%) and total nitrogen (0.119%) were found in Mimosa and Calopogonium treated plots, respectively. Concentration of available phosphorus, calcium and magnesium in all green crops treated plots were above the critical values, while available potassium content was above the critical value in Guatemala, Citronella and Mimosa treated plots. Changes in soil pH and available potassium were significant, while changes in organic carbon content, total nitrogen and available calcium were insignificant. Changes in available phosphorus and magnesium were significant. The Agriculturists 2014; 12(2) 34-38


2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Hai-Bang Ly ◽  
Thuy-Anh Nguyen ◽  
Binh Thai Pham

Soil cohesion (C) is one of the critical soil properties and is closely related to basic soil properties such as particle size distribution, pore size, and shear strength. Hence, it is mainly determined by experimental methods. However, the experimental methods are often time-consuming and costly. Therefore, developing an alternative approach based on machine learning (ML) techniques to solve this problem is highly recommended. In this study, machine learning models, namely, support vector machine (SVM), Gaussian regression process (GPR), and random forest (RF), were built based on a data set of 145 soil samples collected from the Da Nang-Quang Ngai expressway project, Vietnam. The database also includes six input parameters, that is, clay content, moisture content, liquid limit, plastic limit, specific gravity, and void ratio. The performance of the model was assessed by three statistical criteria, namely, the correlation coefficient (R), mean absolute error (MAE), and root mean square error (RMSE). The results demonstrated that the proposed RF model could accurately predict soil cohesion with high accuracy (R = 0.891) and low error (RMSE = 3.323 and MAE = 2.511), and its predictive capability is better than SVM and GPR. Therefore, the RF model can be used as a cost-effective approach in predicting soil cohesion forces used in the design and inspection of constructions.


2017 ◽  
Vol 14 (4) ◽  
pp. 692-706 ◽  
Author(s):  
Baghdad Science Journal

This study focused on benthic algae (epipelic and attached algae on concrete lining stream) in Bani-Hassan stream in Holly Karbala, Iraq. The qualitative and quantitative studies of benthic algae were done by collecting 240 samples from five sites in the study area for the period from December 2012 to November 2013. Also, the environmental variables of the stream were examined in term of temporary and spatial. The results showed that the stream was alkaline, hard, oligohaline and a well aerated. The total nitrogen to the total phosphorus (TN: TP) ratio indicates nitrogen limitation. 129 species of benthic algae belonging to 57 genera were identified. Bacillariophyceae (diatoms) was the predominant taxon (95 species) followed by Chlorophyceae (16 species), Cyanophyceae (14 species), Euglenophyceae (3 species) and Pyrophyceae (one species). Some genera were found throughout the study period: Nitzschia, Navicula, Cymbella, Gomphonema, Surirella, Cocconeis, Aulacoseira, Oscillatoria, Lyngbya, Spirulina, and ? Scenedesmus. Site 3 recorded the highest total number of algae in spring 2013, and the lowest total number was at site 5 in Autumn 2013. The chlorophyll-a concentration did not match the total number of algae.


Author(s):  
K M Ahtesham Hossain Raju ◽  
Shinji Sato

Response of sand dune when overwashed by tsunami or storm surge, is investigated by conducting small scale laboratory study. Dune consisting of initially wet sand and initially dry sand are tested for three different sand grain sizes. Overtopping of water and the corresponding sediment transport are analyzed. These data set can be used to validate mathematical models associated with dune sediment transport as well as prediction of dune profile.


2020 ◽  
Vol 4 (1) ◽  
pp. 6-13
Author(s):  
Sing Lui Lo ◽  
Tzuen Kiat Yap ◽  
Cheng Ann Chen ◽  
Teruaki Yoshida

A comparison of zooplankton abundance and community in the seagrass and non-seagrass areas of Limau-limauan and Bak- Bak waters within the newly established Tun Mustapha Marine Park was made during 15-17 May 2017. Samples were collected via horizontal tow of a 140 μm plankton net. Environmental variables (temperature, salinity, DO, pH, turbidity) showed no significant differences among the study sites. However, zooplankton showed increasing abundance from non-seagrass, seagrass edge, to seagrass areas at Limau-limauan, while abundance values were comparable among the stations at Bak-bak. Overall zooplankton abundance was significantly higher at the seagrass areas relative to the non-seagrass station at Limau-limauan (p < 0.005), while no statistical difference was found at Bak-Bak (p < 0.21). Mean canopy height was 3-fold higher (p < 0.001) at Limau-limauan than Bak-Bak, suggesting the importance of seagrass bed structural complexity in habitat preference for zooplankton. Cluster analysis revealed the zooplankton community from the seagrass area at Limau-limauan was different from that at seagrass edge and non-seagrass areas, which may be attributed to the influence of seagrass meadows in forming characteristic zooplankton compositions. Marked differences in zooplankton composition and abundance even in close vicinity of sites suggest the importance of local small-scale variations in seagrass habitats in shaping the zooplankton community.


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