Humus Layer Research Articles

Pyrogenous transformations of steppe landscapes in the south-east of the Russian plain (natural parks in Volgograd region as a case study)

For a long time fires have been and still are one of the powerful factors for transforming steppe landscapes. The current condition and pyrogenous transformations of geosystems in the south-east of the Russian Plain were examined. The following methods of field complex landscape research were used, such as semi-portable methods of “key sites”, of crop (quadrat) areas and others. The article focuses on the conclusions about the pyrogenous transformations of geosystems drawn on the basis of long-term field observation on the territory of the Donskoy natural park and the Elton natural park of Volgograd Region. Monitoring has revealed that pyrogenous transformations of geosystems appear to pose a serious threat to biological and landscape diversity of steppe. Under the influence of fire, self-regulation processes in steppe geosystems slow down and resistance to external influence reduces. The structure simplifies, the homogeneity of vegetation cover increases, grass stand and overall projective cover decreases, wood-shrub vegetation dies out. The colourful aspects of the steppe are vaguely displayed. For the long term (up to 3-5 years) biological productivity of geosystems considerably reduces from 1.5 to 3 times. The upper layer of humus burns out, soil fertility decreases and aridization of local pyrogenous geosystems increases. Evaporation speeds up, soil humidity deficit goes up, underground water level goes down, springs run dry. Wind and water erosion processes are being activated. Fires destroy sites of reproduction, recreation and feeding for animals and also habitats of rare and endangered species. Pyrogenic transformation is the most serious real threat to the biological and landscape diversity of the steppes.

Humus microhabitat affects distributions of soil fungi and bacteria in a temperate mountain forest

AbstractHumus layer has an important effect on the diversity and spatial distribution of microbes. However, the role of partitioning of humus layer microhabitats for soil microbial diversity has been poorly documented. In this study, 120 soil samples were collected from a 5‐ha forest dynamic monitoring sample plot in a deciduous broad‐leaved forest. Clustering analysis was used to delineate microhabitats by humus layer. We explored diversity and community composition of soil fungi and bacteria using Illumina sequencing of the ITS rRNA gene and 16S rRNA gene region on the MiSeq platform. We investigated the diversity, species composition, and the microhabitat preferences of fungi and bacteria and then analyzed the effects of environmental factors on soil fungi and bacteria. Our results showed that the diversity, species composition, and the indicator species of the fungal and bacterial community varied among different humus layer microhabitats. In network analysis, the specialization indexes showed that 16.20%/22.30% of the fungal/bacterial operational taxonomic units (OTUs) had the characteristics of distribution specialization for humus layer microhabitats. Mantel test showed that the main environmental drivers of fungi and bacteria were not consistent among the four microhabitats. Our findings indicated that the distribution of soil microbes among humus layer microhabitats is not random, but specialized. We furthermore found that there were differences in the relationship between soil microbes and environment among microhabitats defined by humus layer. Together, these findings suggest the importance of partitioning of humus layer microhabitats in maintaining local diversity in a soil microbial community.

Variation of carbon density components with overstory structure of larch plantations in northwest China and its implication for optimal forest management

Information about the variation of carbon density components of larch plantation (LP) with changing overstory stand structure is lacking, which limits multifunctional forest management. This study sought to address these components in the Liupan Mountains of northwest China. It showed that stand age, tree density, tree biomass, and canopy density are important stand structure parameters influencing the amplitude and composition of carbon density. The results showed that, with rising stand age, the carbon density of both overstory tree and humus layers increased, the carbon density of the understory vegetation layer (shrubs and herbs) decreased, and the carbon density of soil layer (0–100 cm) first increased and then slightly decreased. However, the total ecosystem carbon density increased with rising stand age. With rising tree density and canopy density, the overstory carbon density increased, up to the thresholds of about 1800 trees/ha and 0.7 respectively, but after that increased very slowly; while the understory vegetation carbon density decreased continuously with rising tree density, but decreased with rising canopy density, first very slowly up to the range of 0.6–0.7 and after that very quickly. With rising overstory tree biomass, the humus layer carbon density increased, while soil layer carbon density first increased to a certain threshold, then leveled off or slowly decreased. With rising canopy density, the humus and soil carbon density first increased to the threshold of 0.7 and 0.67, respectively, then decreased. Therefore, the optimum canopy density of 0.7 maintains the highest total ecosystem carbon density with its highest or relatively higher components. Such a tradeoff among the carbon components informs multifunctional forest management since every carbon component is related to specific functions/services of the LP ecosystems.

How to Restore Invertebrate Diversity of Degraded Heathlands? A Case Study on the Reproductive Performance of the Field Cricket Gryllus campestris (L.)

BackgroundNitrogen (NOx, NHy) and acidifying (NOx, NHy, SOx) deposition has reduced the biodiversity of European dry heathlands. Restoration efforts such as sod-cutting (removal of vegetation, litter and humus layer) often shifted these systems from N to P limitation and have had limited success in restoring the invertebrate community. Possible reasons for this include the unresolved acidification and a change in food plant stoichiometry. Here, we investigate how liming and P addition change food nutritional quality and their consequences for invertebrate performance.MethodsWe performed feeding experiments with field crickets (Gryllus campestris), using plant material collected from a full factorial field experiment with liming and P addition. We related female reproduction as measure of individual fitness to elemental ratios of plants fed to the crickets.ResultsP addition stimulated cricket daily reproduction and shortened their reproductive period, resulting in no difference in total reproduction. Liming greatly reduced both daily and total reproduction and resulted in more females cannibalizing on their male mates. Females that did so could partly offset the liming induced reduction in reproduction, suggesting dietary deficiency. P-addition improved food quality (lower N:P ratios) while liming led to skewed Mn:Mg and Fe:Mg ratios that compare unfavorably to ratios found in terrestrial invertebrates.ConclusionIncreased plant N:P ratio following sod-cutting constrains the reproductive potential in Gryllus campestris in a non-linear way. Liming reduced nutritional quality, likely by inducing deficiencies in Fe or Mn.Management ImplicationsHigh-impact restoration management practices such as sod cutting and liming cause new problems for invertebrates rooted in ecological stoichiometry. Since P-addition only partially offsets these negative effects, we instead advocate the use of less intensive N removal management and weaker buffering agents to reduce soil acidification. Furthermore, a reduction in N emission is paramount as it will remove the need for disruptive interventions.

Phosphorus Leaching From Naturally Structured Forest Soils Is More Affected by Soil Properties Than by Drying and Rewetting

Foliar phosphorus (P) concentrations in beech trees are decreasing in Europe, potentially leading to reductions in the trees’ growth and vitality. In the course of climate change, drying and rewetting (DRW) cycles in forest soils are expected to intensify. As a consequence, P leakage from the root zone may increase due to temporarily enhanced organic matter mineralization. We addressed the questions whether sites with different soil properties, including P pools, differ in their susceptibility to DRW-induced P leaching, and whether this is affected by the DRW intensity. A greenhouse experiment was conducted on naturally structured soil columns with beech saplings from three sites representing a gradient of soil P availability. Four DRW cycles were conducted by air-drying and irrigating the soils over 4 hours (fast rewetting) or 48 hours (slow rewetting). Leachates below the soil columns were analyzed for total P, and molybdate reactive P (considered as inorganic P). The difference was considered to represent organically bound P. Boosted regression trees were used to examine the effects of DRW and soil characteristics on P leaching. Contrary to a first hypothesis, that P leaching increases upon rewetting with the intensity of the preceding desiccation phase, intense soil drying (to pF 3.5 to 4.5) did not generally increase P leakage compared to moderate drying (to pF 2 to 3). However, we observed increased inorganic P concentrations and decreased organic P concentrations in leachates after drying to matric potentials above pF 4. Also against our expectations, fast rewetting did not lead to higher leakage of P than slow rewetting. However, the results confirmed our third hypothesis that the site poorest in P, where P recycling is mainly limited to the humus layer and the uppermost mineral soil, lost considerably more P during DRW than the other two sites. The results of our experiment with naturally structured soils imply that intensified drying and rewetting cycles, as predicted by climate-change scenarios, may not per se lead to increased P leaching from forest soils. Soil properties such as soil organic carbon content and texture appear to be more important predictors of P losses.

Formation of ecological component of consumer properties of roads

Abstract. Problem. The issue of the impact of construction projects on the environment is extremely relevant and complex. Analysis of publications. The study of the negative impact of rolling stock, dust, noise, vibration, emissions during the operation of engines, as well as the impact of construction processes on the environment were engaged in such scientists as I.Ye. Evgeniev, RA Kizima, D.W. Зерка-лов, М.В. Немчинов, О.Л. Boychenko and others [1, 3, 4, 8, 9]. The aim is to assess the degree of impact of the road and transport on the environment. Presenting main material. Consumer properties of roads are a set of indicators that directly meet the needs of road users: safety, speed, continuity, comfort of traffic; road capacity, in particular the ability to pass cars and road trains with permitted axle loads, total weight and dimensions; ecological and aesthetic condition of the road; level of service and information support [2]. Ecological safety of the highway depends on the technical level, operational condition of the road and road structures, intensity and composition of traffic and characterizes the impact of the road on the environment within the limits of environmental standards, including harmful vehicle emissions, noise pollution, migration of animals, reptiles etc. [6]. Cars with gasoline engines are especially harmful in this regard. Diesel engines have a much lower level of toxicity and contain much less harmful substances. On the entire area of land occupied by the road and the construction of the road complex, on temporarily allotted land for reserves, quarries and other developments should be removed fertile layer of soil with bulldozers that cut and move the soil some distance. In the course of performance of this work the soil is exposed to mechanical disturbance. The construction area becomes a category of disturbed lands, which include lands with a removed or covered humus layer, not suitable for agricultural and forestry use without prior restoration of fertility [3, 7, 10, 11]. Conclusions. In order to protect the environment, many countries around the world are introducing laws designed to limit the negative impact of vehicles on the state of the biosphere, which requires the creation of modern environmental legislation and regulatory framework for environmental safety.

Nitrogen accumulation in forest floors with introduced Pinus pinea and Pinus pinaster in dune site.

Introduced stone pine (Pinus pinea L.) and maritime pine (Pinus pinaster Aiton) stands were sampled 60years after plantation in Istanbul-Durusu (Terkos), Turkey. Sampling was conducted at four different developmental stages (mean diameter of trees at 1.3-m height (DBH) in stands: SDF = < 8cm, MDF = 8-20cm, LDF = 20-36cm, and UDF > 36cm), with 15 replicated sample plots for each species and developmental stage, for a total of 120 sample plots. The forest floor was sampled in 5 replications in each sample plot. The forest floor samples were divided into two layers: L + F (litter + fermentation) and H (humus), and the oven dry mass and nitrogen (N) content were determined. As a result, the masses of the total forest floor and of both layers were significantly different among the development stages with an increasing trend in maritime pine stands despite no significant difference found in the mass of the humus layer in stone pine stands. However, total forest floor accumulation significantly increased with the development stage (28-60 t/ha in stone pine and 17-64 t/ha in maritime pine). In both species, the N concentrations in the forest floor layers differed significantly among the development stages, and the N concentrations tended to increase as the development stage increased in the L + F layer, whereas a fluctuating trend was observed in the H layer. Although the N content of the humus layer of stone pine did not show a significant difference among the development stages, the N content in the total forest floor was determined to be 0.1-0.5 t/ha in maritime pine and 0.2-0.5 t/ha in stone pine. The relationship between the mean stand DBH and the N stock of the total forest floor was determined to have a higher correlation in maritime pine (R2 = 0.8) than stone pine (R2 = 0.4). In conclusion, the nitrogen concentrations and nitrogen contents of the forest floor were remarkably different in stands introduced with different tree species, indicating the accumulation of forest floor nitrogen.

Influence of Slope Direction on the Soil Seed Bank and Seedling Regeneration of Castanopsis hystrix Seed Rain

Objective: To investigate the impact of different slope directions on the quantity and quality of the soil seed bank and seedling germination process of Castanopsis hystrix plantations. Method: Fixed sample plots in forest stands of Castanopsis hystrix were established on different slope directions (sunny slope, semi-sunny slope, semi-shady slope, and shady slope). The characteristics of the forest stand were investigated, and per-wood scaling was carried out. The temporal dynamics of the seed rain and seed bank were quantified using seed rain collectors and by collecting soil samples from different depths. The quantity and quality of the seeds were determined, and the vigor of mature seeds was measured throughout the study. Results: (1) The diffusion of Castanopsis hystrix seed rain started in mid-September, reached its peak from late October to early November, and ended in mid-December. (2) The dissemination process, occurrence time, and composition of the seed rain varied between the different slope directions. The seed rain intensity on the semi-sunny slope was the highest (572.75 ± 9.50 grains∙m−2), followed by the sunny slope (515.60 ± 10.28 grains∙m−2), the semi-shady slope (382.13 ± 12.11 grains∙m−2), and finally the shady slope (208.00 ± 11.35 grains∙m−2). The seed rain on the sunny slope diffused earliest and lasted the longest, while the seed rain on the shady slope diffused latest and lasted the shortest time. Seed vigor and the proportion of mature seeds within the seed rain were greatest on the semi-sunny slope, followed by the sunny slope, semi-shady slope, and the shady slope. (3) From the end of the seed rain to August of the following year, the amount of total reserves of the soil seed banks was highest on the semi-sunny slope, followed by the sunny slope then the semi-shady slope, and it was the lowest on the shady slope. The amount of mature, immature, gnawed seeds and seed vigor of the soil seed bank in various slope directions showed a decreasing trend with time. The seeds of the seed bank in all slope directions were mainly distributed in the litter layer, followed by the 0–2 cm humus layer, and only a few seeds were present in the 2–5 cm soil layer. (4) The seedling density of Castanopsis hystrix differed significantly on the different slope directions. The semi-sunny slope had the most seedlings, followed by the sunny slope, semi-shady slope, and the shady slope. Conclusions: The environmental conditions of the semi-sunny slope were found to be most suitable for the seed germination and seedling growth of Castanopsis hystrix, and more conducive to the regeneration and restoration of its population.

New Materials From Excavation «Orient» at Olbian Necropolis

At the excavation site in Olbia in 2010—2019 a new sector was investigated in wide areas, which was called the «Orient» after the name of the nearest benchmark. The specific features of this site were established, which was used for burials from the middle of the VI c. BC before the beginning of the III c. AD. In this regard, the generalization of the results obtained has become relevant, as well as the introduction of finds from the Roman period into the scientific circulation. In total, 1064 m2 were uncovered during the research. The average depth was 1,0—1,1 m from the modern surface. The stratigraphy of the excavation is simple: a layer of turf and humus up to 0,2 m thick lies on top, below there is a layer of light (dark yellow) sandy loam with various impurities, and under it is a layer of red-colored pre-continental loam with separate inclusions of «white-eye». In this area, 70 burials of various types of different time periods were discovered, as well as 62 other objects associated with the funeral and memorial tradition. 24 burials and ten other objects are dated by the Roman period. Eight types of burial structures have been identified. Based on this, the following conclusions were identified. In the Roman period, rare types of burial structures appeared in the area under study, in number greater than in the rest of the necropolis. There is a lack of uniformity in the layout and direction of burials. The memorial sites are characterized by the complete absence of gravestones known at Olbian necropolis of the Roman period.

Influence of Anthropogenic Impact on Alteration in the Alluvial Soil Fertility Indicators

The article presents studies on establishing the influence of anthropogenic impacts on alluvial soils of agricultural lands. To solve the problem set, tasks were determined to estimate the degree of damage caused to soils of agricultural lands as a result of the soil humus layer loss or closure. These tasks included establishing the degree of alteration in soil fertility indicators for agricultural lands in regard to pH volume; organic matter content; degree of provision with K2O and P2O5 accessible forms as a result of violating technology of the damaged land stripping and reclamation. Nature of changes in granulometric (grain) and micro-aggregate soil composition is demonstrated. Study objects included agricultural land territories with soil samples of alluvial granular soil taken at the depth of 0-5 cm and 5-20 cm. Necessity is demonstrated to study in detail the agroecological assessment of land use systems and the development of differentiated measures ensuring reproduction of soil fertility, crop growth and territory ecological sustainability. Negative processes are manifested to a varying degree on agricultural land in most administrative regions of Russia including agricultural land in the Orel Region, which requires creation of the ecologically sustainable land use system. Since transformation of compounds entering the ecological system primarily occurs in the soil, which acts as a filter and as the factor of transformation and accumulation of the entering substances, agrobiological features of soil composition and properties make it extremely sensitive to anthropogenic impact. As a result of scientific research, it was revealed that the studied area experienced a decrease in soil fertility main indicators of the alluvial soils and destruction (deterioration) of the fertile soil layer as a result of exposure to anthropogenic influence. Rates of decrease in the organic matter content in soil layer as a result of the soil humus layer damage are shown. Significant fluctuations in the amount of exchangeable potassium in the soils of anthropogenically damaged agricultural lands are established. Degree of decrease in the amount of available phosphorus in soils without humus layer is revealed. Significant alteration in the granulometric (grain) composition of the damaged land soil is proved.

Agroecological assessment of the effectiveness of different systems of soil protection measures in the reproduction of fertility of slope gray forest soils

The increasing anthropogenic impact on the slopes, the involvement of new slope lands in the production sphere require reliable substantiation of their erosion resistance. The study of the effectiveness of the influence of the contour-band organization of the territory and various doses of fertilizers on the intensity of rain and snowmelt runoff, the composition and properties of flat gray forest soils was the main goal of our study. The object of the study was a plot of gray forest middle loamy soils located on the slopes of the western exposure, in 12 soil sections. The article presents a study of the influence of the contour-band structure of plots using cattle droppings and top dressing on the fertile properties of gray forest soils. We used standard research methods to determine the amount of humus and determine the aggregate properties of the soil, as well as to determine the properties of the solid phase of the soil density. We established the level of impact of the forest belt organized in the study area, while taking into account that we applied top dressing on the study area, which affects the nominal influence of factors that led to an increase in the environmental stability of the studied soils. It is proved that runoff-regulating contour forest belts provide optimization of density and increase in soil porosity, improve water-air regime, activate living organisms of agrobiocenosis, increase the thickness of the humus layer, content and reserves of humus in the soil up to 3,6% and 130,7 t/ha depending on its location on the slope. It is established that the use of fertilizers as top dressing on the studied destroyed soils significantly increases the yield of plant crops, as well as increases their environmental sustainability. The study of slopes from the standpoint of assessing, analyzing, and predicting their erosion resistance is an important direction of soil protection agriculture and in solving the food insecurity in Russia. Due to the intensive reduction of the area of agricultural land, the decrease in soil fertility, the problem of anti-erosion protection of land requires an immediate solution.

Системи удобрення батату (ipomoеa batаtas) в умовах Лівобережного Лісостепу України

Системи удобрення батату (ipomoеa batаtas) в умовах Лівобережного Лісостепу України

The soil quality of the world's largest refugee campsites located in the Hill forest of Bangladesh and the way forward to improve the soil quality

The Rohingya refugee camps in Bangladesh are located in the forest areas of the Cox's Bazar South Forest Division. The construction of refugee camps has caused detrimental changes in the natural vegetation and soil quality of the campsites. The objectives of this study were to develop a database on the soil quality of the block plantation sites and to prescribe native species for plantation and site quality improvement. A total of 204 soil samples from 34 sites of block plantations and control-denuded hill sites were collected from the refugee camps. Soil physical properties (depth of humus layer, bulk density, soil texture) and chemical properties (pH, electrical conductivity (EC), organic carbon, and nutrients (N, P, and K) of the collected samples were measured. Depth of soil humus layer was varied from 0.6 to 2.5 cm and only 4% sampling points possessed the humus layer. Comparatively (p < 0.05) higher bulk density (1.64 g/cm3) was observed for the control-denuded sites. Soil EC found to vary significantly (p < 0.05) among the plantations types and the control-denuded hill sites. Comparatively lower concentration of soil organic carbon and nutrients (N, P, and K) were observed for the control-denuded hill sites. While comparatively higher stocks of carbon and nutrients were observed for block plantations without terraces. This study has prescribed 40 native tree species for plantation in the campsites. However, periodic monitoring of the soil quality properties and carbon stock and sequestration are at a time interval are needed to track the restoration performance of the studied areas.

ВЛИЯНИЕ ПОЧВЕННО-КЛИМАТИЧЕСКИХ УСЛОВИЙ УДМУРТСКОЙ РЕСПУБЛИКИ НА УРОЖАЙНОСТЬ И ХИМИЧЕСКИЙ СОСТАВ ЗЕРНА ЯЧМЕНЯ СОРТА РАУШАН

The productivity of barley Raushan 24.9-53.1 tons per hectare on the farm (SKHPK) them. Michurin, Vavozhsky district of the Udmurt Republic for 2013-2019 had a positive average correlation (r = 0,46) with the pH of the arable layer, a positive weak correlation with the content in the arable layer of mobile phosphorus (r = 0,26), exchange potassium (r = 0.12) and humus (r = 0,12). The crop of 2017, had more potassium, sulfur, phosphorus, magnesium, silicon, calcium, sodium, manganese, tin, iron, rubidium, strontium, barium, zirconium, copper, zinc, titanium, selenium, nickel, vanadium, gadolinium, lithium, germanium, cobalt, tungsten, beryllium, cadmium, than their content in the grain of the 2018 crop. In 2018, the yield was lower by 14,2 centner per hectare of the 2017 crop, and barley kernels contained more bromine, aluminum, boron, molybdenum, thorium, chromium, cerium, lanthanum, niobium, tantalum, gallium

Monitoring of heavy metals in agricultural soils of the Republic of Khakasia

The production of environmentally friendly, safe food is one of the conditions contributing to the sustainable development of rural areas. Special attention is paid to the measures aimed to prevent the ingress and accumulation of heavy metal ions in agricultural products. Most researchers deal with the content of gross forms of heavy metals in agricultural soils, while it is the mobile forms that have a significant effect on their “transition” into production and accumulation. The article presents the results of studies on the content of mobile forms of cadmium, lead and copper in agricultural soils in different landscape and climatic zones of the Republic of Khakassia. It was found that the average values of concentrations of the mobile forms of heavy metals in the humus layer are within the maximum permissible concentrations. The content of lead varies from 0.3 to 2.2 mg / kg, copper - from 0.18 to 0.4 mg / kg, cadmium - from 0.01 to 0.2 mg / kg. The content of mobile forms of cadmium, lead and copper varies from year to year. During the monitoring, the oscillatory dynamics of changes in the concentration of heavy metals in the soil was revealed. The ratio of mobile forms of heavy metals (Pb: Cu: Cd) decreases in the following sequence: chestnut soils → southern chernozems → ordinary and leached chernozems → gray forest and soddy-podzolic soils.

Precipitation regime controls bryosphere carbon cycling similarly across contrasting ecosystems

In arctic and boreal ecosystems, ground bryophytes play an important role in regulating carbon (C) exchange between vast belowground C stores and the atmosphere. Climate is changing particularly fast in these high‐latitude regions, but it is unclear how altered precipitation regimes will affect C dynamics in the bryosphere (i.e. the ground moss layer including senesced moss, litter and associated biota) and the closely associated upper humus layer, and how these effects will vary across contrasting environmental conditions. Here, we set up a greenhouse experiment in which mesocosms were assembled containing samples of the bryosphere, dominated by the feather moss Hylocomium splendens, and the upper humus layer, that were collected from across a boreal forest chronosequence in northern Sweden which varies strongly in nutrient availability, productivity and soil biota. We tested the effect of variation in precipitation volume and frequency on CO2 exchange and dissolved organic carbon (DOC) export, and on moss growth. As expected, reduced precipitation volume and frequency lowered net CO2 efflux, DOC export and moss growth. However, by regulating moisture, the lower bryosphere and humus layers often mediated how precipitation volume and frequency interacted to drive C dynamics. For example, less frequent precipitation reduced moss growth only when precipitation volume was low. When volume was high, high moisture content of the humus layer helped avoid moss desiccation. Variation in precipitation regime affected C cycling consistently in samples collected across the chronosequence, despite large environmental variation along the sequence. This suggests that the bryosphere exerts a strong buffering effect on environmental variation at the forest floor, which leads to similar responses of C cycling to external perturbations across highly contrasting ecosystems. As such, our study indicates that projected increases in droughts and ground evapotranspiration in high‐latitude regions resulting from climate change will consistently reduce C losses from moss‐dominated ecosystems.

Moisture content variation of ground vegetation fuels in boreal mesic and sub-xeric mineral soil forests in Finland

Forest fire risk in Finland is estimated with the Finnish Forest Fire Index (FFI), which predicts the fuel moisture content (FMC) of the forest floor. We studied the FMC variation of four typical ground vegetation fuels, Pleurozium schreberi, Hylocomium splendens, Dicranum spp., and Cladonia spp., and raw humus in mature and recently clear-cut stands. Of these, six were sub-xeric Pinus sylvestris stands, and six mesic Picea abies stands. We analysed the ability of the FFI to predict FMC and compared it with the widely applied Canadian Fire Weather Index (FWI). We found that in addition to stand characteristics, ground layer FMC was highly dependent on the species so that Dicranum was the moistest, and Cladonia the driest. In the humus layer, the differences among species were small. Overall, the FWI was a slightly better predictor of FMC than the FFI. While the FFI generally predicted ground layer FMC well, the shape of the relationship varied among the four species. The use of auxiliary variables thus has potential in improving predictions of ignitions and forest fire risk. Knowledge of FMC variation could also benefit planning and timing of prescribed burns.

Effect of Slope on Soil Carbon Storage in Prescribed Burning -- A case study of Pinus Kesiya in Jinggu County Yunnan Province

Compared control forest and prescribed burning forest of six slope of humus layer thickness, loads and organic carbon storage, and these soil levels organic carbon content and carbon storage in Pinus Kesiya, and confirmed to be suitable for carrying out prescribed burning. The experimental data showed that prescribed burning before and after, humus layer thickness of FS and GS are highly statistically significant (P<0.01), others were statistically significant (P<0.05). Loads and organic carbon storage of FS are highly statistically significant (P<0.01), GS, SS, AS and DS are statistically significant (P<0.05). Soil organic carbon content of FS, GS and DS on 0-60cm level are highly statistically significant (P<0.01), others slopes are statistically significant (P<0.05), FS and GS on 20-40cm are highly statistically significant (P<0.01), BS, AS and DS are statistically significant (P<0.05), lat slope and GS on 40-60cm are highly statistically significant (P<0.01), BS is statistically significant (P<0.05). Soil organic carbon storage of SS on 0-20cm is statistically significant (P<0.05), others are highly statistically significant (P<0.01), FS, GS and DS on 20-40cm are highly statistically significant (P<0.01), BS and AS are statistically significant (P<0.05), FS on 40-60cm is highly statistically significant (P<0.01), GS, BS and DS are statistically significant (P<0.05). Prescribed burning can decrease loads in forest, and carbon sequestration in different slope is different, preferred to FS to prescribed burning, next considering GS and BS, those can gain better efficiency, prescribed burning could not be carried out in SS, AS and DS.

Research on decomposition rate of fungi based on temperature and humidity model

Fungus is one of the decomposers in biosphere. Through its unique decomposition effect, it decomposes, converts and absorbs the organic matters in animal and plant remains of the humus layer. Fugus plays an essential role in not merely maintaining the carbon cycle but ensuring the ecosystem on earth under the environment of geochemical cycle, which is beneficial to the stability of the Earth’s environment and the sustainable development of biodiversity. Our team simulated the decomposition of fungi by establishing a mathematical model, aiming to study the following questions: How do fungi with different traits interact and decompose the litter layer in a given land environment; What effect will moisture and temperature have on the decomposition process of fungi in different environments; environmental change trends and kinetic significance; fungal competition in a specific environment; taking into account the growth rate, the decomposition rate of fungi is estimated by the model . A variety of methods are used in the process of model establishment and data analysis: ‘single variable control’ experiment, Python software data analysis, Matlab software data analysis, system dynamics analysis and error analyzing and processing. Strictly control the simulation experiment conditions, guarantee the scientificity and rationality of the experimental data, eliminate interference factors, reduce gross errors, and improve the accuracy of experimental data.

Varieties of raspberries (&lt;i&gt;Rubus idaeus&lt;/i&gt; L.) introduced in Central Yakutia

The results of studying biological properties and productivity of introduced varieties of common raspberry are presented. Objects of research were varieties of common raspberries ( Rubus idaeus L.) Arochnaya, Prelest, Persik, Novost Kuzmina, Marlboro, Vislukha, Kaliningradskaya. Variety Novost Kuzmina adapted to local conditions was used as a control. The studies were carried out in 2016–2018 in a fruit and berry garden. Band planting pattern was used 3.0 × 0.5 m. Agrotechnology applied is generally accepted in the area with bending and heeling in shoots with a layer of earth or humus in late autumn. The study was carried out according to the generally accepted method. On average, over the years during the study period, raspberry varieties entered the phase of the beginning of the growing season in early – mid-May (May 6–16) with a sum of positive temperatures of 79.3–121.3º. The earliest budding time was observed for Marlboro variety. Raspberry flowering began in the third part of June, 39–44 days after the start of the growing season. The flowering period of the studied varieties is extended. Raspberries ripened in late July. The end of growth was not observed in any varieties. As a result of the collection varietal study of raspberries, a high-yielding variety Prelest (3.6 t/ha) was identified. Varieties Arochnaya and Persik were distinguished as yielding large-sized fruit (105.5–106.8 g/100 berries). These varieties are recommended for cultivation on the personal plots of land, farms and other agricultural enterprises in Central Yakutia and for the use in breeding work as sources of high productivity and large-sized fruit.