The Role of El Nino Variability and Peatland in Burnt Area and Emitted Carbon in Forest Fire Modeling

This study was conducted to model fire occurrence within El Nino variability and peatland distribution. These climate and geographical factors have a significant impact on forest fires in tropical areas such as Indonesia. The re-analysis dataset from ECMWF was observed with respect to climate characteristics in Indonesian El Nino events. The INFERNO (INteractive Fire and Emission algoRithm for Natural envirOnments) was utilized to simulate fires over Borneo Island due to its capability to simulate large-scale fires with simplified parameters. There were some adjustments in this INFERNO model, especially for peat fire as peatland has a significant impact on fires. The first was the contribution of climate to the peat fire which is represented by long-term precipitation. The second was the combustion completeness of peat fire occurrence that is mainly affected by human-induced peat drainage. The result of the model shows that El Nino variability mainly affected peat fires but was unable to well simulate the above-ground fire. It increased the burnt area during strong El Nino but overestimated the fires during low/no El Nino season due to lack of peat fire ignition in the calculation. Moreover, as the model did not provide peat drainage simulation, it underestimated the carbon emission. This model has shown promising results by addressing key features in limited input data, but improving some simulations is necessary for regulating weak/no El Nino conditions and carbon combustion of peat fire.

Post-pyrogenic dynamics of the vegetation cover of the Barskoe raised bog (Vologda Region, Russia)

The study deals with the issues of restoration of peat bogs exposed to the pyrogenic factor. The work was carried out in the Barskoe raised bog, at sites unaffected and directly affected by the ground fire of 2002. A decade later, these sites differed in species composition, phytocoenosis structure, and biomass accumulation rates. Post-pyrogenic changes in the vegetation cover of the raised bog were associated with a slight decrease in species richness, loss of moisture-demanding bog species and an increase of mesophyte’s and xerophyte’s roles, simplification of the mire sites structure towards the loss of complexity, reduction of phytocoenotic diversity, as well as an increase in the dry biomass stocks with a 1.3–1.4-fold decrease in the photosynthetic phytomass and a 6.4–6.7-fold increase in the mortmass. The restoration rate of the mire exposed to pyrogenic transformation can be accelerated by increasing its water table and the prevention of new fires.

SALINATION OF POSTPIROGENIC SOILS OF UKRAINIAN ROZTOCHYA

Introduction. One of the most dangerous phenomena of fires in natural ecological systems is the physicochemical and structural changes of soils due to temperature (pyrogenic) factor. Such types of fire, except for the instantaneous destruction of the biocenosis, have a secondary impact on all components of the environment for many years - ecosystem restoration is slow or non-existent, riverbeds change, new ecotopes formed, physicochemical properties of soil change irreversibly. Pyrogenic degradation of edaphotopes leads to their slow recovery. Many scientific works are devoted to this issue in Ukraine and abroad. All of them can be classified into the following groups: pyrogenic degradation ofpeatlands, physicochemical properties of post-pyrogenic soils, pyrogenic succession. Postpyrogenic soils require detailed research depending on specific natural and climatic conditions, which, in addition to temperature, are crucial in the processes of ecological renaturalization of vegetation.Aim and methods. The work aims to establish the relationship between the post-pyrogenic factor and soil salinity overtime for the Ukrainian Roztochya. For measuring the flame temperature used fluke thermal imager. Soil moisture was determined using a moisture meter "MG-44". Soil acidity was determined using a contact device "KS-300V". Modelling the acidity distribution into the genetic horizons was performed using a demo version of Surfer software. Statistical values are processed using MS Excel. In the research used: statistical, chemical, pedologic, phytocenotic methods.Results and discussion. Due to the high salinity of forest fires, we determined the content of chlorides, sulfates, phosphates in the samples. We found that the highest content of chlorides and sulfates is inherent in the investigated area №4, namely: in the horizon of 0-5 cm chloride content is 432.1 mg/kg, in 5-10 cm – chloride content is 267.1 mg/kg, in 10-20 cm – chlorides content is 142.7 mg/kg; in the horizon of 0-5 cm sulfate content is 235.7 mg/kg, in 5-10 cm – sulfate content is 160.3 mg/kg, in 10-20 cm – sulfate content is 131.7 mg/kg. The extremely salt content in the area with the model fire indicates significant salinization due to the ground fire. The level of chlorides and sulfates is much lower than in other areas, depending on the age of ground fires occurrence, which indicates the natural restoration of edaphotopes and alignment of salinity to background values.Conclusions. As a result of a research of the salinity of post-pyrogenic soils of the Ukrainian Roztochya, we found that the restoration of edaphic indicators of the loam depends on the age of the ground fires occurrence. For researching of acidity and salinity of soils accepted the range of occurrence of grassland forest fires four years ago We found that in the investigated areas exposed to fire long ago, the indicators of acidity and salinity correspond to the background values and are much lower than the same values for the model fire area.

Lignin, cellulose and nutrient deposition in litters of Bambusa vulgaris stands in a regenerating forest in Ile-Ife, Nigeria

The lignin, cellulose and nutrient deposition of litters were assessed in four 0.06 ha plots of Bambusa vulgaris stands in a regenerating forest in Ile-Ife, Nigeria, 35 years after ground fire, with a view to providing information on these parameters which are generally lacking in the forest ecosystem. The collected litters were sorted into leaves and twigs, oven-dried at 70 °C to a constant weight, ground and analysed for lignin, cellulose and nutrients. The total lignin and cellulose content in the litters showed significant (p≤0.05) monthly variation. There was no significant (p ≥ 0.05) difference in the monthly nutrient deposition of Na, Mg, K, Fe, N, P, Mn, Zn and Cu, but there was significant difference in the monthly nutrient deposition of C and Ca through the litter fall fraction (p ≤ 0.05) in the bamboo stands in the secondary rainforest. The depositions of C, N, Ca, Mg and Cu were higher in the bamboo stands but lower in Na, Mn and Zn deposition in 1990 and 2013 studies. The bamboo stands contributed significantly to the carbon sequestration, nutrient dynamics and regeneration status of the forest.