Carbon Reserves Research Articles

Polyhydroxybutyrate (PHB)-Based Biodegradable Polymer from Agromyces indicus: Enhanced Production, Characterization, and Optimization.

Recently, there has been significant interest in bio-based degradable plastics owing to their potential as a green and sustainable alternative to synthetic plastics due to their biodegradable properties. Polyhydroxybutyrate (PHB) is a biodegradable polymer that is produced by bacteria and archaea as carbon and energy reserves. Due to its rapid degradation in natural environments, it can be considered a biodegradable plastic alternative. In the present study, a dye-based procedure was used to screen PHB-producing bacteria isolated from mangrove soil samples. Among the seven isolates, Agromyces indicus (A. indicus), identified by means of 16S rRNA analysis, accumulated the highest amount of PHB. The extracted polymer was characterized by a UV–Vis spectrophotometer, Fourier-transform infrared (FTIR) spectroscopy, and for the presence of the phbB gene, which confirmed the structure of the polymer as PHB. The maximum PHB production by A. indicus was achieved after 96 h of incubation at a pH of 8.0 and 35 °C in the presence of 2% NaCl, with glucose and peptone as the carbon and nitrogen sources, respectively. The strain was found to be capable of accumulating PHB when various cheap agricultural wastes, such as rice, barley, corn, and wheat bran, were used as the carbon sources. The response surface methodology (RSM) through the central composite design (CCD) for optimizing the PHB synthesis was found to be highly efficient at augmenting the polymer yields. As a result of the optimum conditions obtained from the RSM, this strain can increase the PHB content by approximately 1.4-fold when compared with an unoptimized medium, which would substantially lower the production cost. Therefore, the isolate A. indicus strain B2 may be regarded as one of the best candidates for the industrial production of PHB from agricultural wastes, and it can remove the environmental concerns associated with synthetic plastic.

Increase in carbon input by enhanced fine root turnover in a long-term warmed forest soil

Fine root litter represents an important carbon input to soils, but the effect of global warming on fine root turnover (FRT) is hardly explored in forest ecosystems. Understanding tree fine roots' response to warming is crucial for predicting soil carbon dynamics and the functioning of forests as a sink for atmospheric carbon dioxide (CO2). We studied fine root production (FRP) with ingrowth cores and used radiocarbon signatures of first-order, second- to third-order, and bulk fine roots to estimate fine root turnover times after 8 and 14 years of soil warming (+4 °C) in a temperate forest. Fine root turnover times of the individual root fractions were estimated with a one-pool model. Soil warming strongly increased fine root production by up to 128 % within one year, but after two years, the production was less pronounced (+35 %). The first-year production was likely very high due to the rapid exploitation of the root-free ingrowth cores. The radiocarbon signatures of fine roots were overall variable among treatments and plots. Soil warming tended to decrease fine root turnover times of all the measured root fractions after 8 and 14 years of warming, and there was a tendency for trees to use older carbon reserves for fine root production in warmed plots. Furthermore, soil warming increased fine root turnover from 50 to 106 g C m−2 yr−1 (based on two different approaches). Our findings suggest that future climate warming may increase carbon input into soils by enhancing fine root turnover. If this increase may partly offset carbon losses by increased mineralization of soil organic matter in temperate forest soils is still unclear and should guide future research.

Numerical Modeling of Biogeochemical Carbon Cycles in Swamp Ecosystems

A dynamic model of biogeochemical carbon cycles in swamp ecosystems is proposed. There are fast and slow biogeochemical cycles. Fast cycles operate in the biosphere and include photosynthesis, vegetative growth, and decomposition. Swamp ecosystems are one of the significant reservoirs of biogeochemical cycles. It is known that huge reserves of carbon in the form of slightly decomposed organic matter are preserved in the swamps. They are active sources of methane and carbon dioxide runoff from the atmosphere.
 Mathematical models of dynamic processes in ecology can be divided into two categories: quantitative and qualitative. Quantitative models, as a rule, are aimed at solving problems of predicting numerical indicators of the dynamics of real systems. They must be modified to consider specific climatic conditions, special types of swamp vegetation, and hydrological regime for their successful application.
 Qualitative models written as systems of differential equations assume the finding of singular points, their classification and study for stability, the construction of phase portraits, etc. Such models rarely lend themselves to quantitative verification, but provide important knowledge and understanding of processes in nature. A qualitative study of the system of ordinary differential equations describing carbon cycles is carried out, the types of singular points are investigated, integral curves and phase portraits are constructed.

ORGANIC MATTER CONTENT AND HUMUS RESERVES IN NATURAL SOILS OF ROSTOV AGGLOMERATION

The research aims to study the content of organic matter in typical chernozem, its distribution in the soil profile under herbaceous and wooden phytocenoses. Organic matter plays a key role in the functioning of soils and their stable performance of ecological functions, including – the protection function. This is particularly relevant in the growing urbanization. The research analysis includes 40 full-profile sections of migration-segregated chernozems (typical carbonate) laid on the upland soil of the Rostov agglomeration. We determined organic matter by high-temperature catalytic combustion on a TOC-L CPN Shimadzu in an SSM-5000A solid sample combustion unit. Based on the data obtained, we calculated the organic carbon reserves. Statistical analysis included the calculation of the Mann-Whitney U-test to consider significant differences in the samples of indicators under wooden and herbaceous phytocenoses and descriptive statistics. The research results showed the influence on the organic carbon content of such a widespread type of anthropogenic impact as planting trees in the steppe zone. Comparison of the total organic carbon content values in similar genetic horizons under herbaceous and wooden phytocenoses indicates the spatial heterogeneity of this indicator, associated primarily with the type of land use. The supply of humus for Rostov chernozems under herbaceous phytocenoses was assessed as low and under wooden phytocenoses – as average. In the one-meter layer of natural chernozems of the Rostov agglomeration, humus reserves are 387 t/ha, which corresponds to the average supply level. Thus, the park and recreational zone, where wooden vegetation grows, plays a special ecological role in the city as a place of accumulation of an increased amount of organic matter of natural origin compared to other soils of the Rostov agglomeration.

Crop intensification effects on soil quality and organic carbon stocks: a case study of Haramosh Valley in Central Karakorum, Pakistan

ABSTRACT Agricultural operations such as excessive tillage and intense cropping deplete soil organic carbon (SOC), making sustainable agriculture management critical for reducing greenhouse gas (GHG) emissions. This study evaluates the impact of crop intensification on soil quality and soil organic carbon stocks (SOCS) under double cropping (DC) and single cropping pattern (SC) in upper Haramosh of Gilgit, Pakistan. Soil samples were taken from cropping zones (DC and SC) under three depths (0–20, 20–40, and 40–60 cm). Standard methods were used to analyze selected soil quality parameters and SOC. Statistical analysis using ANOVA showed that soil temperature, moisture, pH, SOC, and SOCS highly significantly differed (p < 0.001) for different cropping patterns (DC and SC), whereas bulk density (BD), electrical conductivity (EC), and clay were not significantly different. The SC retained 4.4% more moisture and had lower BD than the DC, while BD increased with increasing depth. The texture of the soil was sandy loam at both cropping zones. The mean SOC and SOCS of SC were greater (by 12%) than in the DC zone. Pearson correlation showed a significant and positive correlation of SOC stock with SOC, moisture (p < 0.01), and EC (p < 0.05), but had a negative correlation with bulk density, pH (p < 0.01), and sand (p < 0.05). DC apparently degraded soil quality and organic carbon reserves, thus reducing the soil health in mountain agriculture.

Deducing Leading Factors of Spatial Distribution of Carbon Reserves in Nanjing Metropolitan Area Based on Random Forest Model.

Improving carbon reserves is considered to be an important way to alleviate global warming. However, there is a lack of research work based on the perspective of metropolitan area, and there is also a lack of analysis on the leading influencing factors of spatial distribution of carbon storage in subregions of metropolitan area. In this study, Nanjing metropolitan area (NMA) is taken as the research area, and the InVEST model is used to calculate the spatial distribution of regional carbon reserves, and the evolution of carbon reserves distribution in recent 20 years is analyzed. Then, based on the random forest (RF) model, taking the whole study area and subareas as the research scope, a regression model of each selected impact factor and carbon reserves is established, and the leading factors of spatial distribution of carbon reserves in NMA are obtained. The results show that the overall carbon reserves level in the study area is in a downward trend. Through the application of the RF model, the leading factors of the spatial distribution of carbon reserves in NMA and its subareas are derived. The research proves that the application of the RF model in the analysis is helpful for city planners and governments to make plans and improve regional carbon storage more effectively.

Purple acid phosphatase2 stimulates a futile cycle of lipid synthesis and degradation, and mitigates the negative growth effects of triacylglycerol accumulation in vegetative tissues.

Storage lipids (mostly triacylglycerols, TAGs) serve as an important energy and carbon reserve in plants, and hyperaccumulation of TAG in vegetative tissues can have negative effects on plant growth. Purple acid phosphatase2 (PAP2) was previously shown to affect carbon metabolism and boost plant growth. However, the effects of PAP2 on lipid metabolism remain unknown. Here, we demonstrated that PAP2 can stimulate a futile cycle of fatty acid (FA) synthesis and degradation, and mitigate negative growth effects associated with high accumulation of TAG in vegetative tissues. Constitutive expression of PAP2 in Arabidopsis thaliana enhanced both lipid synthesis and degradation in leaves and led to a substantial increase in seed oil yield. Suppressing lipid degradation in a PAP2-overexpressing line by disrupting sugar-dependent1 (SDP1), a predominant TAG lipase, significantly elevated vegetative TAG content and improved plant growth. Diverting FAs from membrane lipids to TAGs in PAP2-overexpressing plants by constitutively expressing phospholipid:diacylglycerol acyltransferase1 (PDAT1) greatly increased TAG content in vegetative tissues without compromising biomass yield. These results highlight the potential of combining PAP2 with TAG-promoting factors to enhance carbon assimilation, FA synthesis and allocation to TAGs for optimized plant growth and storage lipid accumulation in vegetative tissues.

TOR signaling in the green picoalga Ostreococcus tauri

Target of rapamycin (TOR) is a master regulator that controls growth and metabolism by integrating external and internal signals. Although there was a great progress in the study of TOR in plants and in the model alga Chlamydomonas, scarce data are available in other green algae. Thus, in this work we studied TOR signaling in Ostreococcus tauri, the smallest free-living eukaryote described to date. This picoalga is particularly important because it has a key site at the base of the green lineage and is part of the marine phytoplankton, contributing to global photosynthesis. We investigated OtTOR complex in silico and experimentally, by using first- and second-generation TOR inhibitors, such as rapamycin and PP242. We analyzed the effect of TOR down-regulation on cell growth and on the accumulation of carbon reserves. The results showed that O. tauri responds to TOR inhibitors more similarly to plants than to Chlamydomonas, being PP242 a valuable tool to study this pathway. Besides, Ottor expression analysis revealed that the kinase is dynamically regulated under nutritional stress. Our data indicate that TOR signaling is conserved in O. tauri and we propose this alga as a good and simple model for studying TOR kinase and its regulation.

Komposisi, Struktur dan Cadangan Karbon pada Agroforestri Kopi Arabika di Kabupaten Aceh Tengah, Aceh

Carbon stocks indicates the amount of CO2 that is absorbed and stored in plant biomass coffee, shade trees, undergrowth and litter. Objective research is to analyze the species composition and structure of vegetation and determine the amount of biomass, carbon stocks and CO2 uptake aboveground part in both types of coffee agroforestry with non-destructive methods, using allometric equation, in Central Aceh district. The location of the plot was determined by purposive sampling based on the representation of stands. The dominant value of a species in plants is calculated using the important value index (INP). The composition of agroforestry constituents consisted of 34 species, of which 15 species were found in simple agroforestry and 19 species in complex agroforestry. The horizontal structure of agroforestry consists of 5 diameter classes, with vegetation density decreasing continuously in the number of individuals. Carbon stocks agoforestri types of coffee in a simple decrease with an increase in diameter &lt;10 cm and 10-19.99 cm and the complex agroforestry increases. The highest non-coffee carbon reserves are found at growth rates of 10-19.99 cm in simple agroforestry. The total component of the amount of biomass in simple agroforestry (159. 56 tons ha-1) is greater than the agroforestry complex (142.00 tons ha-1). Total CO2 uptake in both types of agroforestry was (520.16 tonsCO2 ha-1). Total CO2 uptake in simple agroforestry (275.22 tonsCO2 ha-1) was greater than in complex agroforestry (244.94 tonCO2 ha-1).Keywords: arabica coffee, agroforestry, carbon stocks and composition of vegetation

Dominance of Sulfurospirillum in Metagenomes Associated with the Methane Ice Worm (Sirsoe methanicola).

Sirsoe methanicola, commonly known as the methane ice worm, is the only macrofaunal species known to inhabit the Gulf of Mexico methane hydrates. Little is known about this elusive marine polychaete that can colonize rich carbon and energy reserves. Metagenomic analysis of gut contents and worm fragments predicted diverse metabolic capabilities with the ability to utilize a range of nitrogen, sulfur, and organic carbon compounds through microbial taxa affiliated with Campylobacterales, Desulfobacterales, Enterobacterales, SAR324, Alphaproteobacteria, and Mycoplasmatales. Entomoplasmatales and Chitinivibrionales were additionally identified from extracted full-length 16S rRNA sequences, and read analysis identified 196 bacterial families. Overall, the microbial community appeared dominated by uncultured Sulfurospirillum, a taxon previously considered free-living rather than host-associated. Metagenome-assembled genomes (MAGs) classified as uncultured Sulfurospirillum predicted thiosulfate disproportionation and the reduction of tetrathionate, sulfate, sulfide/polysulfide, and nitrate. Microbial amino acid and vitamin B12 biosynthesis genes were identified in multiple MAGs, suggesting nutritional value to the host. Reads assigned to aerobic or anaerobic methanotrophic taxa were rare. IMPORTANCE Methane hydrates represent vast reserves of natural gas with roles in global carbon cycling and climate change. This study provided the first analysis of metagenomes associated with Sirsoe methanicola, the only polychaete species known to colonize methane hydrates. Previously unrecognized participation of Sulfurospirillum in a gut microbiome is provided, and the role of sulfur compound redox reactions within this community is highlighted. The comparative biology of S. methanicola is of general interest given research into the adverse effects of sulfide production in human gut microbiomes. In addition, taxonomic assignments are provided for nearly 200 bacterial families, expanding our knowledge of microbiomes in the deep sea.

Aspen growth is not limited by starch reserves

All photosynthetic organisms balance CO2 assimilation with growth and carbon storage. Stored carbon is used for growth at night and when demand exceeds assimilation. Gaining a mechanistic understanding of carbon partitioning between storage and growth in trees is important for biological studies and for estimating the potential of terrestrial photosynthesis to sequester anthropogenic CO2 emissions.1,2 Starch represents the main carbon storage in plants.3,4 To examine the carbon storage mechanism and role of starch during tree growth, we generated and characterized low-starch hybrid aspen (Populus tremula×tremuloides) trees using CRISPR-Cas9-mediated gene editing of two PHOSPHOGLUCOMUTASE (PGM) genes coding for plastidial PGM isoforms essential for starch biosynthesis. We demonstrate that starch deficiency does not reduce tree growth even in short days, showing that starch is not a critical carbon reserve during diel growth of aspen. The low-starch trees assimilated up to ∼30% less CO2 compared to the wild type under a range of irradiance levels, but this did not reduce growth or wood density. This implies that aspen growth is not limited by carbon assimilation under benign growth conditions. Moreover, the timing of bud set and bud flush in the low-starch trees was not altered, implying that starch reserves are not critical for the seasonal growth-dormancy cycle. The findings are consistent with a passive starch storage mechanism that contrasts with the annual Arabidopsis and indicate that the capacity of the aspen to absorb CO2 is limited by the rate of sink tissue growth.

Development of a lucerne model in APSIM next generation: 2 canopy expansion and light interception of genotypes with different fall dormancy ratings

Lucerne (Medicago sativa L.) canopy expansion, as quantified by leaf area index (LAI), is the crop process that determines the amount of intercepted total radiation during each regrowth cycle. A challenge is to capture seasonal changes of canopy expansion rate in response to the environment. This research integrates parameters and functions of lucerne canopy expansion into the Agricultural Production Systems sIMulator (APSIM) next generation (APSIM NextGen) model (LeafArea module) to simulate canopy expansion and light interception. Over 20 years of detailed field experimental datasets, with multiple treatments, from Lincoln University were used for model development. Functions derived from a fall dormancy (FD) 5 rated genotype were grown under an industry standard defoliation treatment to parametrize the model. These functions were tested further using genotypes with an FD2 or FD10 rating under longer and shorter defoliation regimes, all under irrigated conditions. The APSIM NextGen lucerne model predicted the LAI expansion pattern in each growth cycle as a double sigmoid curve requiring functions that define the lag phase, basal bud initiation, the linear leaf area expansion rate (LAER; m2 m-2 °Cd), and canopy senescence which represents the loss of LAI over time. LAI was well predicted for experiments under the standard (42-day) and long (84 day) defoliation treatments for FD5, with Nash-Sutcliffe efficiency (NSE) of 0.61 and 0.55. However, the derived parameters and functions overestimated LAI under an extreme short defoliation treatment (28-day), NSE values ranged from 0.38 to 0.78. LAER was lower for the short-defoliation intervals (28-day), probably due to a depletion of carbon and nitrogen reverses in perennial organs. For FD2 and FD10, different LAER functions were generated from field observed data and used to improve simulation agreement. There was fair agreement for the 84-day treatment (NSE of 0.32) and the 42-day treatment (NSE of 0.38), but poor agreement for the 28-day treatment for FD10 (NSE = −0.88). The estimated extinction coefficient (k) was the same for seedling and regrowth crops, and consistent across defoliation treatments and FD classes. With the LeafArea module and k value, the APSIM NextGen lucerne model can now estimate daily LAI and intercepted radiation. Future model development includes validating the LeafArea module in different environments. However, a more mechanistic model approach is required to link canopy expansion to carbon and nitrogen reserves in lucerne plants that experience intense defoliation.

Root Carbon Resources Determine Survival and Growth of Young Trees Under Long Drought in Combination With Fertilization.

Current increases in not only the intensity and frequency but also the duration of drought events could affect the growth, physiology, and mortality of trees. We experimentally studied the effects of drought duration in combination with fertilization on leaf water potential, gas exchange, growth, tissue levels of non-structural carbohydrates (NSCs), tissue NSC consumption over-winter, and recovery after drought release in oak (Quercus petraea) and beech (Fagus sylvatica) saplings. Long drought duration (>1 month) decreased leaf water potential, photosynthesis, and NSC concentrations in both oak and beech saplings. Nitrogen fertilization did not mitigate the negative drought effects on both species. The photosynthesis and relative height increment recovered in the following rewetting year. Height growth in the rewetting year was significantly positively correlated with both pre- and post-winter root NSC levels. Root carbon reserve is critical for tree growth and survival under long-lasting drought. Our results indicate that beech is more sensitive to drought and fertilization than oak. The present study, in a physiological perspective, experimentally confirmed the view that the European beech, compared to oak, may be more strongly affected by future environmental changes.

Variations of δ13C in water-soluble compounds during spring phenology of typical tree species in the warm temperate zone

In this study, we examined the regularity of phenological rhythmical change of plant water-soluble compound δ13C (δ13Cwsc) in spring for two typical tree species in the warm temperate zone of China, Pinus tabuliformis and Robinia pseudoacacia. The δ13Cwsc in each organ of those two species in the spring phenological period were measured to explore the relationship between δ13Cwsc and related environmental factors. The results showed that there were significant differences in δ13Cwsc values of each organ between P. tabuliformis and R. pseudoacacia, with higher δ13Cwsc(-25.03‰±0.01‰) in the new shoot of P. tabuliformis. The δ13Cwsc value in the non-photosynthetic organs were 0.83‰-1.8‰ higher than that in the photosynthetic organs, while the δ13Cwsc value in the aboveground part was generally lower than that in the underground part. As spring progressing, different carbon storage strategies were found between two species. When the terminal bud of P. tabuliformis opened, the carbon was obtained from the proximal old leaves. At the beginning of leaf development, photosynthetic products accumulated by old leaves could not meet the growth requirements for new leaves and roots, with 90% of which depending on the carbon reserve in branches and stems. When full leaf having developed, the photosynthetic function of both new and old leaves recovered and the carbon consumed by branches and stems was gradually replenished. For R. pseudoacacia, at the beginning of leaf bud opening and leaf spreading, branches were the main carbon source for new leaves and roots. When leaves were fully unfolded, mature leaves with high capacity of carbon sequestration became the primary carbon source. Results of principal component analysis showed that temperature during observation period, ≥10 ℃ accumulated temperature, sunshine duration and solar radiation were the main factors influencing δ13Cwsc, which could explained 86.3% of the total variation. The δ13Cwsc values of both species was negatively correlated with temperature and relative humidity, but positively correlated with the difference of saturated water pressure, ≥10 ℃ accumulated temperature and sunshine duration. The main environmental factors affecting plant δ13Cwsc varied during the phenological process. Our results could provide a reference for more accurate estimation of spring organ carbon distribution pattern of regional typical tree species, and also a theoretical basis for formulating scientific and reasonable forest management strategy.

Analysis Distribution of Biomass Carbon of Grasslands, Shrubs, and Rainfed Rice Fields on Dry Land in the Aceh Besar District Indonesia

Abstract This research was conducted to determine plant biomass, carbon potential, and CO2 reserve potential in understory vegetation in general, namely grasslands, shrubs, and rainfed rice fields. The sampling of the research was carried out randomly and intentionally, and was limited to the vegetation of reeds, shrubs and rainfed land bushes in the Aceh Besar District of Indonesia. The sample was taken based on a digitized map obtained from overlaying the land use map, slope map, soil type map, and Aceh Besar government map. Measurement of biomass in the vegetation of Imperata, shrubs, and rainfed rice fields is in accordance with procedures from the Indonesian National Standard (2011) and the World Agroforestry Center. The area of bush vegetation is larger than that of rainfed rice fields and grasslands. In general, the plants found in bush vegetation are Acacia leucoeplhoea, Mimosa pudica, Cyperus rotundus, and Eleusine indica. Grassland vegetation has one plant only, namely, Pennisetum purpureum. The vegetation of rainfed rice fields consists of the Oryza sativa type of plant. Plant biomass, carbon [C] content, and carbon potential in bush vegetation are greater than that of grassland and rainfed rice fields, as well as plant biomass reserves, plant biomass carbon and total CO2 reserves. Shrubs and woody plants render the potential for biomass, carbon, and CO2 absorption greater than that of grassland and rainfed rice fields. This is in accordance with the research that the increase in biomass is followed by an increase in potential carbon storage. Parameters that affect biomass indirectly will also affect carbon storage in a biomass and in an ecosystem, namely, individual density, stem diameter, tree species diversity, and soil. The density of trees in an area will affect the increase in carbon stocks through an increase in biomass. This is because the vegetation of shrubs does not only consist of undergrowth, but also of woody stems such as Acacia leucoeploea, making carbon stock potential in bush vegetation greater than that of grassland and rainfed rice fields, as shrubs cover an area of 96,962.2 ha, hence larger than that of grasslands and rainfed rice fields.

Interaction of drought- and pathogen-induced mortality in Norway spruce and Scots pine.

Pathogenic diseases frequently occur in drought‐stressed trees. However, their contribution to the process of drought‐induced mortality is poorly understood. We combined drought and stem inoculation treatments to study the physiological processes leading to drought‐induced mortality in Norway spruce (Picea abies) and Scots pine (Pinus sylvestris) saplings infected with Heterobasidion annosum s.s. We analysed the saplings' water status, gas exchange, nonstructural carbohydrates (NSCs) and defence responses, and how they related to mortality. Saplings were followed for two growing seasons, including an artificially induced 3‐month dormancy period. The combined drought and pathogen treatment significantly increased spruce mortality; however, no interaction between these stressors was observed in pine, although individually each stressor caused mortality. Our results suggest that pathogen infection decreased carbon reserves in spruce, reducing the capacity of saplings to cope with drought, resulting in increased mortality rates. Defoliation, relative water content and the starch concentration of needles were predictors of mortality in both species under drought and pathogen infection. Infection and drought stress create conflicting needs for carbon to compartmentalize the pathogen and to avoid turgor loss, respectively. Heterobasidion annosum reduces the functional sapwood area and shifts NSC allocation patterns, reducing the capacity of trees to cope with drought.

Carbon stock in the litter on the Skolivski Beskydy territory (Ukrainian Carpathians)

Purpose. Investigate the carbon stock in the forest litter in the Skolivski Beskydy (Ukrainian Carpathians), taking into account the mountainous features of the region, and model the regional regression equation for calculating the carbon stock in the litter based on the obtained data. Methods. Field studies of carbon stock in forest litter by the technique of Skorodumov. Determination of mineral parts and bedding was determined by dry ashing. Mathematical modeling. Results. The work was carried out on the territory of the Skolivski Beskydy (Ukrainian Carpathians). The selected area provides an opportunity to study the impact of abiotic factors on the formation of carbon stocks in forest litter, as well as to compare these reserves in different types of forest use. As a result of route research, the calculation of the carbon stock in the forest litter on the laid transects of the Skole Beskids was calculated. Carbon reserves were calculated on the basis of eight transects in the Skolivski Beskydy. From the obtained results, we found the dependence of carbon stock in forest litter on the species composition of the stand, exposure, and slope steepness. Based on the results obtained, it was possible to form a regional regression equation for converting data from the state forest cadastre to calculate carbon stocks in the litter, considering the altitude and slope steepness. Conclusions. The correlation between carbon stock in forest litter and abiotic factors (stand composition, exposure, slope steepness) was revealed, which allowed creating of a regional regression equation for the conversion of state forest cadastre data for carbon stock calculations in forest litter.

Abandoned Fishpond Reversal to Mangrove Forest: Will the Carbon Storage Potential Match the Natural Stand 30 Years after Reforestation?

Mangroves are essential carbon reserves, and their role in carbon sequestration is remarkable. However, anthropogenic pressures such as aquaculture development threatened this highly susceptible ecosystem. Thus, the need to rehabilitate abandoned aquaculture ponds is a must to offset the ecological losses over the economic gains derived from these mangrove land-use changes. Thus, we chose a reforestation site of a once heavily utilized fishpond devastated by a tsunami in the late 1970s in Zamboanga del Sur, Philippines. We then established a similar study plot in a nearby natural mangrove forest as a point of reference. We determined the heterogeneity in vegetation and estimated the aboveground and soil carbon storage capacities. We also examined the distinct changes in species composition and zonation from the seaward towards the landward zones. About 30 years after the abandoned fishpond rehabilitation, we found the tree density of the Rhizopora mucronata Lamk. and Avicenia marina (Forsk.) Vierh-dominated reforestation site was higher (271 trees ha−1) compared to that of the Rhizophora apiculata Blume-dominated natural stand (211 trees ha−1) (p &lt; 0.05). The total aboveground biomass at the natural mangrove forest was 202.02 Mg ha−1, which was close to that of the reforestation site (195.19 Mg ha−1) (p &gt; 0.05). The total aboveground C in the natural mangrove forest was 90.52 Mg C ha−1, while that of the reforestation site was 87.84 Mg C ha−1 (p &gt; 0.05). Surprisingly, the overall soil C content at the natural forest of 249.85 Mg C ha−1 was not significantly different from that of the reforestation site with 299.75 Mg C ha−1 (p &gt; 0.05). There was an increasing soil C content trend as the soil got deeper from 0–100 cm (p &lt; 0.05). The zonation patterns established across the landward to seaward zones did not affect the aboveground and soil carbon estimates (p &gt; 0.05). Our study highlights the effectiveness of abandoned fishpond rehabilitation and calls for continuous restoration of the remaining abandoned aquaculture ponds in the country because of their ability to sequester and store carbon. Lastly, their potential to store huge amounts of carbon that will counterbalance anthropogenic CO2 emissions is likewise highlighted.

The Last Trees Standing: Climate modulates tree survival factors during a prolonged bark beetle outbreak in Europe

Plant traits are an expression of strategic tradeoffs in plant performance that determine variation in allocation of finite resources to alternate physiological functions. Climate factors interact with plant traits to mediate tree survival. This study investigated survival dynamics in Norway spruce (Picea abies) in relation to tree-level morphological traits during a prolonged multi-year outbreak of the bark beetle, Ips typographus, in Central Europe. We acquired datasets describing the trait attributes of individual spruce using remote sensing and field surveys. We used nonlinear regression in a hypothesis-driven framework to quantify survival probability as a function of tree size, crown morphology, intraspecific competition and a growing season water balance. Extant spruce trees that persisted through the outbreak were spatially clustered, suggesting that survival was a non-random process. Larger diameter trees were more susceptible to bark beetles, reflecting either life history tradeoffs or a dynamic interaction between defense capacity and insect aggregation behavior. Competition had a strong negative effect on survival, presumably through resource limitation. Trees with more extensive crowns were buffered against bark beetles, ostensibly by a more robust photosynthetic capability and greater carbon reserves. The outbreak spanned a warming trend and conditions of anomalous aridity. Sustained water limitation during this period amplified the consequences of other factors, rendering even smaller trees vulnerable to colonization by insects. Our results are in agreement with prior research indicating that climate change has the potential to intensify bark beetle activity. However, forest outcomes will depend on complex cross-scale interactions between global climate trends and tree-level trait factors, as well as feedback effects associated with landscape patterns of stand structural diversity.

Statistical optimization of medium components and growth conditions to enhance Polyhydroxybutyrate yield by Bacillus endophyticus MTCC 13038

Polyhydroxybutyrate (PHB) is a biodegradable polymer accumulated as carbon and energy reserve granules by several bacteria and is ideal substitute for petroleum-based polymers. The present study aimed to isolate PHB producing bacteria and optimize medium components and growth conditions to enhance PHB yield. Potent PHB accumulating bacterial strain was isolated from oil spilled soil and identified as Bacillus endophyticus based on its 16S rRNA analysis. Sudan Black B staining method was used to detect PHB granules and affirmed by using Fourier Transform Infrared Spectroscopy. Differential scanning calorimetry analysis was conducted for thermal analysis of extracted PHB polymer. Bacillus endophyticus showed highest PHB accumulation utilizing glucose as the carbon and potassium nitrate as the nitrogen source which were further optimized along with physical parameters like pH and temperature using Box and Behnken method. The highest biomass (7.49 g/L) and PHB (3.67 g/L) were observed at pH 7, temp. 37ºC, glucose 25 g/L and potassium nitrate 0.1 g/L. Bacillus endophyticus was found to accumulate up to 49% PHB under optimized conditions. These results indicate the potential application of Bacillus endophyticus at the industrial level for PHB production.