Mangrove Above-Ground Biomass and Carbon Stock in the Karimunjawa-Kemujan Islands Estimated from Unmanned Aerial Vehicle-Imagery

Blue carbon ecosystems in the Karimunjawa Islands may play a vital role in absorbing and storing the releasing carbon from the Java Sea. The present study investigated mangrove above-ground biomass (AGB) and carbon stock in the Karimunjawa-Kemujan Islands, the largest mangrove area in the Karimunjawa Islands. Taking the aerial photos from an Unmanned Aerial Vehicle combined with Global Navigation Satellite System (GNSS) measurements, we generated Digital Surface Model (DSM) and Digital Terrain Model (DTM) with high accuracy. We calculated mangrove canopy height by subtracting DSM from DTM and then converted it into Lorey’s height. The highest mangrove canopy is located along the coastline facing the sea, ranging from 8 m to 15 m. Stunted mangroves 1 m to 8 m in height are detected mainly in the inner areas. AGBs were calculated using an allometric equation destined for the Southeast and East Asia region. Above-ground carbon biomass is half of AGB. The AGB and carbon biomass of mangroves in the Karimunjawa-Kemujan Islands range from 8 Mg/ha to 328 Mg/ha, and from 4 MgC/ha to 164 MgC/ha, respectively. With a total area of 238.98 ha, the potential above-ground carbon stored in the study area is estimated as 16,555.46 Mg.

Seasonal Dynamics of Organic Carbon and Nitrogen in Biomasses of Microorganisms Affected by Different Tillage Systems

The main purpose of this study was to determine the size and direction of the seasonal dynamics of organic carbon (Сmicro) and nitrogen (Nmicro) biomass of microorganisms and microbial index (Cmicro : Corg) of natural and agrocenoses with their different uses. Field research methods involved taking of soil samples in 0-10-, 10-20- and 20-40 сm layers. Under laboratory conditions, the content of total soil carbon was determined by dry oxygen combustion on a Vario EL III analyzer (Elementar Analyzensysteme, Hanau, Germany). The carbon content of microbial biomass (Сmicro) was determined by chloroform fumigation extraction method (CFE). To freshly taken soil samples (2 hours) and soil samples after their 24-hour fumigation with chloroform vapors, 0.5 M K2SO4 was added to extract biomass lysis products of soil microorganisms. The content of organic carbon and nitrogen in the biomass of microorganisms in the obtained filtrates was determined on the Elementar Liqui TOC II, Analyzensysteme GmbH, Germany. The carbon content of microbial biomass was calculated from the difference between carbon in fumigated and control samples using a factor of 0,45 - for carbon and 0,54 – for nitrogen. The microbial index of soils was determined by the ratio between the carbon of microorganisms and the total organic carbon of the soil – Cmicro : Corg • 100 (%). Average values and confidence intervals were determined for each defined indicator. The Bonferoni method was used to correct the errors of multiple comparative samples of a one-way ANOVA analyze. K. Pearson’s linear correlation analysis was used to establish the relationships between the dynamics of carbon biomass of microorganisms and organic carbon of the soil during the growing season. Our research has shown the dynamics of Сmicro, Nmicro, Сmicro : Nmicro and Cmicro : Corg during the growing season. Analysis of the box plot showed the largest amplitude of Сmicro changes in the upper 0-10 cm layer of izogumusol. The smallest difference in the quartile range (IQR0,25-0,75) was for no-till and overhang (Ab) in the upper 0-10-, no-till (NT) and fallow (F) - in the layer 10-20- and plowing (CT) - in a layer of 20-40 cm. The content of organic carbon biomass of microorganisms in the upper layer of izogumusol at the beginning of the growing season had the highest values of Ab (577,79  1,64 mg/kg), NT (485,43  1,97 mg/kg) and CT (470,43  0,77 mg/kg), the smallest - for F (370,15  2,18 mg/kg). The content of Nmicro during this period decreased from Ab to Comb (combined tillage), NT, CT, Rot (rotary tillage), RT (reduced (ridge) tillage) and F, respectively. In the 20-40 cm layer, the highest values of Сmicro and Nmicro were observed in mid-July. The lowest values of Сmicro and Nmicro and the largest – Сmicro : Nmicro were found in late August for all variants and layers of the study. The dynamics of the microbial index resembled the trends of Сmicro and Nmicro. The largest share of Smicro in Sorghum during the growing season, on average was: - Ab (1,82  1,85 %) and NT (1,66  1,52 %) - in the layer 0-10-, - Ab (1,23  1,27 %) and NT (1,29  1,32 %) - in the layer 10-20- and - Ab (1,19  1,09 %) and F (1,11  1,077 %) - in a layer of 20-40 cm. Different use of izogumusol affected the amplitude of seasonal changes of Сmicro and Nmicro and did not affect on their direction. The maximum content of Сmicro and Nmicro was observed at the beginning of the growing season - in a layer of 0-10 cm and in mid-July - in a layer of 20-40 cm, the minimum - at the end of the summer period. During this period, the widest ratio of Сmicro : Nmicro was for F and CT - in the layer 0-20 cm and CT and Rot - in the layer 20-40 cm. The Pearson’s correlation coefficient between Сmicro and Corg increased from the upper 0-10- to the lower 20-40 cm layer of izogumusol. "Strong" and "high" negative correlations have been established between Сmicro and Corg, but no pattern has been found between the correlation coefficient and tillage technologies.

Degradation Effect of UV Synergistic Biomass Activated Carbon Materials on Phenol Pollutants in Water

The purpose of the study is to purify the water containing phenol pollutants. The degradation effect of phenol pollutants in water is studied through the combined action of UV and biomass-activated carbon. First, the phenol solution is prepared in the laboratory to simulate the polluted water. Second, the phenol adsorption effects of UV synergistic biomass activated carbon, biomass activated carbon and ordinary industrial activated carbon under different influencing factors are compared by experiments. Finally, the results are analyzed and the conclusions are drawn. The results show that the UV synergistic biomass activated carbon has the strongest degradation ability for phenol, and the highest removal rate is 66.5% when the shaking time is 65 minutes. The adsorption ability of the industrial activated carbon for phenol is the worst. When the initial concentration of phenol is 25mg/L, the maximum phenol removal rate is 96.8%. The maximum phenol removal rate of biomass activa ted carbon appears in the initial concentration of phenol and the phenol removal rate is 60 mg/L. The reaction temperature has little effect on the phenol removal rate of UV synergistic biomass activated carbon and biomass activated carbon. The phenol removal ability of UV synergistic biomass activated carbon and biomass activated carbon reaches the highest when the dosage of activated carbon is 2.0 g, and the rates are 96.4% and 91.1%, respectively. When the pH of the solution is 7, the removal rate of UV synergistic biomass activated carbon reaches a maximum of 97%. When the pH of the solution is 6, the removal rate of biomass-activated carbon reaches the maximum. When the pH of the ordinary industrial activated carbon is 7, the removal rate is the maximum. Due to different influencing factors, UV synergistic biomass activated carbon has the strongest phenol degradation ability. This study provides a reference for the purification of polluted water.

Switchable Structure Promoted Leaching Free Atomically Dispersed Pt Catalyst for Low Carbon Biomass Polyol Oxidation

Achieving efficient catalytic conversion over heterogeneous catalyst with excellent resistance against leaching is still a grand challenge for sustainable chemical synthesis in aqueous solution. Herein, we devised a leaching free atomically dispersed Pt1/hydroxyapatite (HAP) catalyst with unique switchable structure via a simple and green in-situ anchoring strategy. Gratifyingly, this robust Pt1/HAP catalyst exhibits remarkable catalytic selectivity and catalyst stability for the selective oxidation of C2-C4 bio-polyols (e.g., ethylene glycol, propanediol, glycerol and butanediol) to corresponding primary hydroxy acids. X-ray absorption spectroscopy, in-situ Fourier Transform infrared spectroscopy, density functional theory calculation and kinetics study elucidated that the switchable Pt-(O-P) linkages with strong electronic-withdrawing function of PO43− (Pt1-OPO43− active site) not only realize the activation of C-H bond, but also destabilize the transition state from adsorbed hydroxy acids toward the C-C cleavage, resulting in the sharply increased selectivity of hydroxy acids. Moreover, the strong PO43−-coordination effect, originating from the enhanced interaction between positively charged Pt1 and negatively charged OPO43−, provides electrostatic stabilization for the atomically dispersed Pt, ensuring the highly efficient catalysis of Pt1/HAP for over 160 hours without metal leaching. This finding opens up new opportunities for efficient upgrading of bio-polyols over atomically dispersed catalysts.

Porous Activated Carbon Binder-free Scleria sumatrensis Stem-Based for Supercapacitor Application

Green, sustainable and effective development technique to obtain high porous activated carbon biomass based is important to boosting supercapacitor performance with environmentally friendly effect as conversion system and energy storage devices. We reported porous activated carbon binder-free Scleria sumatrensis stem-based as electrode material high performance of symmetric supercapacitor. Precursor biomass of Scleria sumatrensis stem was converted into porous carbon through simple ZnCl2 impregnated with different concentration of 0.4M, 0.5M, 0.6M, and 0.7M at high-temperature phyrolysis. All samples confirmed good amorphous carbon with small amounts of oxidative compounds. In two-electrode system, the optimum sample of ACSS0.6 significantly boosting the specific capacitance as high as 142.62 F g−1 at scan rate of 1 mV s−1. Furthermore, the optimum energy density was found to be 19.80 Wh kg−1 at a maximum power density of 71.35 W kg−1 in 1 M H2SO4 aqueous electrolyte. These results confirm that the porous activated carbon binder-free Scleria sumatrensis stem-based through simple ZnCl2 impregnated as an electrode material to boosting the electrochemical behavior of supercapacitors.

Estimation of Carbon Content in the Páramo Ecosystem of Pasa Population, Ambato Canton, Tungurahua Province

The stored carbon content was determined based on a randomized stratified experimental design by type of vegetation; three sampling units of 400 m2 each were installed, from 3600–4100 m.s.n.m., with intervals of 150 m of altitude. The inventory of herbaceous vegetation was taken using the GLORIA method. For the sampling of the aerial biomass and necromass in the plot, circular subplots were constructed, and the samples were collected in 4 quadrants of 0.25 m2, two in each subplot. Samples of 0–20, 20–40 and 40–60 cm were taken from the soil profile, and the percentage of organic carbon in the soil and the apparent density were evaluated. The results indicate a floristic diversity represented by 44 species, 39 of herbaceous vegetation and 5 of tree vegetation. The carbon content stored in aerial biomass returned a value of 83.88 tC⋅ha−1 for herbaceous vegetation and 158.50 tC⋅ha−1 in tree vegetation, and in terms of necromass, returned values of 0.89 tC-ha−1 and 7.40 tC-ha−1, respectively. The carbon stored in the soil at a depth of 20 cm is 111.84 tC- ha−1 for herbaceous vegetation and 122.45 tC-ha−1 for tree vegetation. Keywords: ecosystem, paramo, tree vegetation, carbon, biomass. Resumen Se determinó el contenido de carbono almacenado en base a un diseño experimental estratificado al azar por tipo de vegetación, se instalaron tres unidades de muestreo de 400 m2 cada una, a partir de 3600–4100 m.s.n.m; con intervalos de 150 m de altitud. El inventario de la vegetación herbácea mediante el método GLORIA, Para el muestreo de la biomasa aérea y necromasa en la parcela se anidaron subparcelas circulares, se recolecto las muestras en 4 cuadrantes de 0.25m2 dos en cada subparcela. En el comportamiento suelo se tomaron muestras de 0–20 cm, 20–40 cm y de 40–60 cm, se evaluó el porcentaje de carbono orgánico en el suelo y la densidad aparente. Los resultados indican una diversidad florística representada por 44 especies, 39 de la vegetación herbácea y 5 de la vegetación arbórea. El contenido de carbono almacenado en la biomasa aérea reporto un valor de 83,88 tC⋅ha−1 para vegetación herbácea y de 158,50 tC⋅ha−1 en la vegetación arbórea, en cuanto a necromasa con valores de 0,89 tC-ha−1 y de 7,40 tC-ha−1 respectivamente. El carbono almacenado en el suelo a 20 cm de profundidad es de 111.84 tC-ha−1 la vegetación herbácea y de 122,45 tC-ha−1 para la vegetación arbórea. Palabras clave: ecosistema, paramo, vegetación arbórea, carbono, biomasa.

Size-Fractionated Biogenic Silica Standing Stocks and Carbon Biomass in the Western Tropical North Pacific: Evidence for the Ecological Importance of Pico-Sized Plankton in Oligotrophic Gyres

Biogenic silica (bSi) standing stocks and carbon (C) biomass of small plankton are rarely studied together in previous analyses, especially in oligotrophic gyres. Within the oligotrophic western tropical North Pacific, based on size-fractionated bSi and biovolume-derived C analyses in three size fractions (i.e., 0.2–2; 2–20; >20 μm), we observed that picophytoplankton (<2 μm) contributed a measurable and significant proportion of both bSi standing stocks and C biomass. The estimated contributions of pico-sized fraction to total bSi standing stocks and living C biomass averaged 66 and 49%, respectively, indicating the ecological importance of small plankton in the Si and C cycles in oligotrophic areas. In contrast, the average contributions of large diatoms (i.e., cells >2 μm) to total bSi standing stocks and living C biomass were 9 and 16%, respectively, suggesting that the role of diatoms in marine Si and C cycles may have been overestimated in previous analyses. Due to the overwhelming predominance of picocyanobacteria in the oligotrophic western tropical North Pacific, their contributions to total bSi stocks and C biomass were quantitatively important and accounted for more of the bSi and C associated with living cells than did diatoms. In addition, water temperature and light intensity were likely the key determinants of the variations in size-fractionated bSi standing stocks and living C biomass, but not nutrient availability. Collectively, these findings encourage a reconsideration of the previously underestimated role of small plankton in understanding the Si and C cycles in the ocean, and may provide insights into the interpretations of disproportionate budgets of Si and C in oligotrophic oceans.