A mathematical model to study the dynamics of carbon capture in forest plantations

Fast-growing forest plantations play an important role in reducing global warming and have great potential for carbon capture. In this study, we aimed to model the dynamics of carbon capture in fast-growing plantations. A mathematical model is proposed consisting of a tridimensional nonlinear system. The variables involved are the amount of living biomass, the intrinsic growth of biomass, and the burned area by forestry fire. The environmental humidity is also considered, assumed as a parameter by simplicity. The solutions of the model are approximated numerically by the Runge-Kutta fourth-order method. Once the equilibria of the model have been obtained and its local stability determined, the analysis of the model reveals that the living biomass, as well as the stored carbon, decreases in each harvest cycle as a consequence of the negative effects of fire on soil properties. Furthermore, the model shows that the maximum area burned is attained always after the maximum volume of biomass is obtained. Numerical simulations show that the model solutions are reasonable for the growth dynamics of a plantation, from a theoretical perspective. The mathematical results suggest that a suitable optimal management strategy to avoid biomass losses in the successive regeneration cycles of the plantation is the prevention of fires together with soil fertilization, applied to fast-growing plantations.

Duckweed: a model for phytoremediation technology

The Lemnaceae or duckweed family comprises 37 species of smallest and simplest flowering plants. Duckweeds have a fast growth rate, can survive under a wide range of temperature and pH conditions and are easy to maintain and harvest which makes them an excellent candidate for bioremediation of wastewaters. The main objective of the present review is to extend an appreciation for the potential of living and non-living biomass of duckweed in remediating waters contaminated with heavy metals. Along with showing the detailed mechanism of phytoremediation by duckweed, the paper also discusses the enhancement of duckweed phytoremediation by the integration of transgenic technology. Furthermore, the paper explores other applications of duckweed specifically as fuel, animal feed, in human nutrition, in medicine and as a life support system. Apart from this, various disposal mechanisms for harvested duckweed have been analysed. Current understanding of removal efficiencies of several contaminants by employing duckweed is limited mainly to laboratory experiments. More concentrated and persistent efforts to develop efficient approaches for the genetic transformation of duckweeds can expand the development and utilization of duckweeds.

Environmental conditions to support blue carbon storage in mangrove forest: A case study in the mangrove forest, Nusa Lembongan, Bali, Indonesia

Pricillia CC, Patria MP, Herdiansyah H. 2021. Environmental conditions to support blue carbon storage in mangrove forest: A case study in the mangrove forest, Nusa Lembongan, Bali, Indonesia. Biodiversitas 22: 3304-3314. Mangrove ecosystems can provide ecosystem services to mitigate climate change by absorbing and storing carbon in their systems. The question arises of how to manage a mangrove forest to store more carbon. The Nusa Lembongan mangrove forest was examined to assess the optimal environmental settings for blue carbon storage in the mangrove ecosystem. Five stations were selected purposively. The parameters observed in each station were aboveground living biomass, mangrove stand density, clay percentage in soil, bulk density, water content, soil organic carbon (%C), and soil organic nitrogen (%N). Based on this study, the total carbon stock in mangrove forest Nusa Lembongan was 68.10 ± 20.92 Mg C ha-1 and equals to 249.95 ± 76.77 MgCO2 ha-1 with a significant contribution of soil carbon stock. This study indicates that the essential parameters that can promote carbon sequestration in mangrove forest Nusa Lembongan were aboveground living biomass, soil organic carbon content and soil organic nitrogen content. In addition, as soil organic carbon content also negatively correlates with bulk density, it also can be considered. These findings can contribute to blue carbon planning and management to improve the effectiveness of the blue carbon project.

Study of Mechanisms Used by Algae to Decrease The Silver Toxicity in Aquatic Environment

In the study SEM, EDS, TEM and UV-vis analysis were used to investigate the biosorption, bioaccumulation and bioprecipitation/bioreduction of silver by freshwater green alga Parachlorella kessleri and to shed light on the reasons of biological silver nanoparticleproduction. When dead biomass of P. kessleri was used for silver removal, majority of silver (75%) was removed within2 min. Biosorption was probably the main mechanisms responsible for Ag+ ions removal from aqueous solutions. However, whenbehaviour of living biomass in the presence of silver ions was studied, the decrease of silver concentration was slower (68% within24 hours) with subsequent increase of silver concentration in the solution and extracellular formation of silver nanoparticles. Theformed AgNPs exhibited a lower toxicity against tested organisms. Algal cells probably used the formation of nanoparticles combinedwith rapid biosorption as detoxification mechanisms against silver toxicity. Bioaccumulation inside the cells played only aminor role in the detoxification process.

Terrestrial ecosystem Si budgets, past and present

<p>Estimates of silicon (Si) pools and fluxes in diverse extant ecosystems have been published, including for grasslands, and deciduous and evergreen forests.  These illustrate diversity in dominant pools of biogenic Si in soils versus living biomass, reflecting the vegetation type and variation in Si accumulation of plant groups. This presentation will explore potential to estimate Si pools and fluxes for a selection of past environments, based on the species recorded in fossil records teamed with Si accumulation data from extant relatives. Where possible, changes over time will also be considered incluing impacts of vegetation on weathering and other envrionmental feedbacks.</p>

The Role Of Biomass In Saving Natural Resources

Biomass is total mass of all living organisms living on Earth. It is very difficult to calculate the biomass of the earth in exact numbers. However, it is estimated that there are 1.7 trillion tons of living biomass on Earth today.

Improving living biomass C-stock loss estimates by combining optical satellite, airborne laser scanning, and NFI data

Policy measures and management decisions aiming at enhancing the role of forests in mitigating climate-change require reliable estimates of C-stock dynamics in greenhouse gas inventories (GHGIs). The aim of this study was to assemble design-based estimators to provide estimates relevant for GHGIs using national forest inventory (NFI) data. We improve basic expansion (BE) estimates of living-biomass C-stock loss using field-data only, by leveraging with remotely-sensed auxiliary data in model-assisted (MA) estimates. Our case studies from Norway, Sweden, Denmark, and Latvia covered an area of >70 Mha. Landsat-based Forest Cover Loss (FCL) and one-time wall-to-wall airborne laser scanning (ALS) data served as auxiliary data. ALS provided information on the C-stock before a potential disturbance indicated by FCL. The use of FCL in MA estimators resulted in considerable efficiency gains which in most cases were further increased by using ALS in addition. A doubling of efficiency was possible for national estimates and even larger efficiencies were observed at the sub-national level. Average annual estimates were considerably more precise than pooled estimates using NFI data from all years at once. The combination of remotely-sensed with NFI field data yields reliable estimates which is not necessarily the case when using remotely-sensed data without reference observations.

Precipitation of low-temperature disordered dolomite induced by extracellular polymeric substances of methanogenic Archaea Methanosarcina barkeri: Implications for sedimentary dolomite formation

A correlation between methanogenesis and dolomite formation has been reported; however, the mechanism underlying this association is not fully understood. In this study, we conducted forced carbonate precipitation experiments at room temperature in calcite-seeded Ca/Mg carbonate solutions containing either purified non-living biomass or bound extracellular polymeric substances (EPS) of the methanogen Methanosarcina barkeri. Purified non-living biomass and bound EPS was used so as to avoid the possible influence of the complex components of the growing microbial culture on carbonate crystallization. Our results demonstrated that non-living biomass of M. Barkeri can enhance the Mg incorporation into calcitic structure and induce the crystallization of disordered dolomite. In the presence of ~113 mg L–1 of non-living biomass, disordered dolomite with ~41 and 45 mol% of MgCO3 was precipitated in solutions with initial Mg:Ca ratios of 5:1 and 8:1, respectively. A systematic increase in the MgCO3 contents of the precipitated Ca-Mg carbonates was also observed with the increased non-living biomass concentration. Bound EPS was shown to be the component of non-living biomass that catalyzed the precipitation of disordered dolomite. At only ~25 mg L–1 of bound EPS, disordered dolomite with ~47 and 48 mol% of MgCO3 was precipitated in solutions with initial Mg:Ca ratios of 5:1 and 8:1, respectively. We propose that adsorption of bound EPS to growing carbonate surfaces through hydrogen bonding is the key to catalyzing disordered dolomite crystallization, and that this mechanism is also applicable to natural EPS-induced dolomite formation. This study provides significant insight into the formation mechanism of microbial-induced dolomite with high δ13C values.