Early Vegetation Research Articles

Soil Respiration in Anthropogenic Disturbed Ecosystems Compared to Deciduous Forests in the Urban Industrial Area

In urban industrial area, mining activity directly affects the dynamic of carbon, and consequently, the release of carbon dioxide (CO2) into the atmosphere. The main objective of this research is to study the impact of most important abiotic environmental factors on soil respiration in post-coalmine ecosystems. The moisture and temperature of the soil, along with CO2 outflow from the soil, were measured over three consecutive seasons, using 92 samples from coalmine heaps and 10 samples from deciduous forests in the same urban industrial region. Based on a survey of 396 species, a cluster analysis distinguished all deciduous and 22 forest plots grown on coalmine heaps from herbaceous plots from same coalmine heaps. The lowest soil respiration rate (0.62 mg CO2 per hour per square meter) was recorded in the herbaceous vegetation class on coalmine heaps, compared to (0.76 mg and 0.96 mg) from coalmine-heap forests and deciduous forests, respectively. Species richness and diversity positively affected soil respiration in heap herbaceous plots, though this effect was less pronounced in forests grown on coalmine heaps and in deciduous mixed forests. Unlike soil water content, soil temperature negatively correlated with soil respiration on coalmine heaps, diverging from the well-studied positive impact of soil temperature and respiration in deciduous mixed forests. Our spatial and temporal analyses emphasize that the water content of the substrate is the most significant abiotic element that affects the soil respiration on coalmine heaps positively during early vegetation succession.

Application of Guar Gum Treatment of Basalt Residual-Soil Shallow Slope in Early Ecological Restoration

This paper found that environmentally friendly guar gum biopolymers are helpful for stopping the erosion of basalt residual-soil shallow slopes, while also improving the problems of poor stability, difficult growth of early vegetation, and weak initial resistance to the rainfall scouring of these slopes under extreme climatic conditions. Then, to illustrate the effects of the guar gum treatment, laboratory tests have been conducted, including a soil strength test, water retention and water absorption tests, a disintegration test, and a simulated rainfall erosion test, and the pattern of its effect on vegetation growth has been explored. The results indicate that as the content of guar gum increases, both the cohesion and angle of internal friction exhibit a trend of first increasing and then decreasing; the angle of internal friction varies within a range of 21° to 26°. The evaporation rate, water absorption rate, and disintegration rate of this guar gum-treated soil were significantly reduced, while the cracking of the surface layer was significantly improved. The disintegration rate of the soil is only about 2%, as the guar gum content is greater than 1%. Moreover, there is no sign indicating that vegetation germination was affected by the guar gum, meaning that it maintains a favorable environment for vegetation to grow. Guar gum-cured slopes were significantly protected under heavy rainfall washout conditions, with a 94.85% reduction in total soil loss from the slope surface compared to untreated slopes. Since the pores of soil are filled with guar gum hydrogel, the erosion resistance of soil is greatly enhanced. The results of this study will provide a scientific basis for engineering the protection of shallow slopes of basalt residual soils.

Postfire Phosphorus Enrichment Mitigates Nitrogen Loss in Boreal Forests.

Net nitrogen mineralization (Nmin) and nitrification regulate soil N availability and loss after severe wildfires in boreal forests experiencing slow vegetation recovery. Yet, how microorganisms respond to postfire phosphorus (P) enrichment to alter soil N transformations remains unclear in N-limited boreal forests. Here, we investigated postfire N-P interactions using an intensive regional-scale sampling of 17 boreal forests in the Greater Khingan Mountains (Inner Mongolia-China), a laboratory P-addition incubation, and a continental-scale meta-analysis. We found that postfire soils had an increased risk of N loss by accelerated Nmin and nitrification along with low plant N demand, especially during the early vegetation recovery period. The postfire N/P imbalance created by P enrichment acts as a "N retention" strategy by inhibiting Nmin but not nitrification in boreal forests. This strategy is attributed to enhanced microbial N-use efficiency and N immobilization. Importantly, our meta-analysis found that there was a greater risk of N loss in boreal forest soils after fires than in other climatic zones, which was consistent with our results from the 17 soils in the Greater Khingan Mountains. These findings demonstrate that postfire N-P interactions play an essential role in mitigating N limitation and maintaining nutrient balance in boreal forests.

Warm‐Season Drying Across Europe and Its Links to Atmospheric Circulation

AbstractWe study drying trends across the central latitude strip of Europe (47.5–52.5°N and 2.5–27.5°E) during 1980–2019 and their links to atmospheric circulation. Daily differences between potential evapotranspiration and precipitation (PET–P) calculated from the E–OBS data are used to characterize dryness, and atmospheric circulation is represented by circulation types classified using daily sea level pressure patterns from the NCEP/NCAR reanalysis. Circulation types favoring dry conditions in vegetation season (April–September) are identified based on daily PET–P, and their temporal changes, seasonal variations, and links to trends in dryness in individual European regions are analyzed. In the early vegetation season (AMJ), drying trends are observed mainly in Western and Central Europe while in the late vegetation season (JAS), they are located predominantly in Eastern Europe. The dry circulation types include all anticyclonic types in all regions, as well as northeast to south (southwest in Eastern Europe) directional types. Trends of the dry circulation types correspond to those of dryness: the largest increase is found during AMJ in Western and Central Europe but during JAS in Eastern Europe. The results show that trends in dryness in the central latitude strip of Europe in the warm half‐year were associated with changes in atmospheric circulation, as the largest increases in frequency of dry circulation types occurred in the regions and months affected by pronounced drying. The increasing frequency of anticyclonic types in AMJ and reduced inflow of moist air masses from the Atlantic are the key factors supporting intensification of dry conditions in European mid‐latitudes.

Restricted plant diversity limits carbon recapture after wildfire in warming boreal forests

Incomplete wildfire combustion in boreal forests leaves behind legacy plant-soil feedbacks known to restrict plant biodiversity. These restrictions can inhibit carbon recapture after fire by limiting ecosystem transition to vegetation growth patterns that are capable of offsetting warmth-enhanced soil decomposition under climate change. Here, we field-surveyed plant regrowth conditions 2 years after 49 separate, naturally-occurring wildfires spanning the near-entire climatic range of boreal Fennoscandia in order to determine the local to regional scale drivers of early vegetation recovery. Minimal conifer reestablishment was found across a broad range of fire severities, though residual organic soil and plant structure was associated with restricted growth of a variety of more warmth-adapted vegetation, such as broadleaf trees. This dual regeneration limitation coincided with greater concentrations of bacterial decomposers in the soil under increased mean annual temperature, potentially enhancing soil carbon release. These results suggest that large portions of the boreal region are currently at risk of extending postfire periods of net emissions of carbon to the atmosphere under limitations in plant biodiversity generated by wildfire and a changing climate.

Phenology and Climate Indices of Maize Hybrids under North Western Himalayan Region of Temperate Kashmir

In the Kharif season of 2021, a field experiment was conducted at the crop research farm of the Division of Agronomy, Faculty of Agriculture, Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir. The primary objective of the study was to investigate the phenology of maize hybrids in relation to agrometeorological indices. The experimental design included two factors: Factor A, representing different irrigation regimes at various growth stages (I1 to I6), and Factor B, consisting of two maize hybrid varieties (Shalimar Hybrid-2 and Shalimar Hybrid-3). The irrigation treatments ranged from early vegetation stage to rainfed conditions. The experiment followed a split plot design with three replications. Results indicated that the treatment I5 (Irrigation at IW/CPE ratio of 0.8) and Shalimar Hybrid-3 exhibited the highest values for key agrometeorological indices, including GDD, HTU, PTU, and HYTU. These findings provide valuable insights into optimizing irrigation practices and selecting suitable maize hybrids for enhanced phenological performance.

Enhancing vegetation formation classification: Integrating coarse-scale traditional mapping knowledge and advanced machine learning

Mapping vegetation formation types in large areas is crucial for ecological and environmental studies. However, this is still challenging to distinguish similar vegetation formation types using existing predictive vegetation mapping methods, based on commonly used environmental variables and remote sensing spectral data, especially when there are not enough training samples. To solve this issue, we proposed a predictive vegetation mapping method by integrating an advanced machine learning algorithm and knowledge in an early coarse-scale vegetation map (VMK). First, we implemented classification using the random forest algorithm by integrating the early vegetation map as an auxiliary feature (VMF). Then, we determined the rationality of classified vegetation types and distinguished the confusing types, respectively, based on the knowledge of the spatial distributions and hierarchies of vegetation. Finally, we replaced each recognized unreasonable vegetation type with its corresponding reasonable vegetation type. We implemented the new method in upstream of the Yellow River based on GaoFen-1 satellite images and other environmental variables (i.e., topographical and climate variables). Results showed that the overall accuracy using the VMK method ranged from 67.7 % to 76.8 %, which was 10.9 % to 13.4 % and 3.2 % to 6.6 %, respectively, higher than that of the method without the early vegetation map (NVM) and the VMF method, based on cross-validation with 20 % to 60 % random training samples. The spatial details of the vegetation map using the VMK method were also more reasonable compared to the NVM and VMF methods. These results indicated that the VMK method can distinctly improve the mapping accuracy at the vegetation formation level by integrating knowledge of existing vegetation maps. The proposed method can largely reduce the requirements on the number of field samples, which is especially important for alpine mountains and arctic region, where collecting training samples is more difficult due to the harsh natural environment.

Biological and phytochemical variation with pre- and post-harvest conditions for the Acanthus mollis L. leaf

This study investigated for the first time the temporal variation of compounds and biological activities in Acanthus mollis leaves harvested during different seasons. Variables like the harvest date, edaphic-climatic conditions, storage, drying process, and extraction methods can potentially affect phytochemicals content, potentially influencing its safety and efficacy. The study was conducted over two consecutive years, and leaves were harvested at three different vegetative stages: early vegetation, pre-flowering, and flowering. The main non-volatile compounds in the harvested leaves' ethanol extracts were quantified using HPLC-PDA (High-Performance Liquid Chromatography with Photodiode Array Detection). Additionally, the antioxidant capacity of the extracts was evaluated using the DPPH (2,2-diphenyl-1-picrylhydrazyl) assay. Finally, the anti-inflammatory activity of the extracts on RAW 264.7 murine macrophages stimulated with LPS (lipopolysaccharide) was studied. Phytochemical analysis revealed different compounds crucial for identifying the most favorable harvesting season for Acanthus mollis. These compounds included DIBOA (2,4-dihydroxy-1,4-benzoxazin-3-one), HBOA (2-hydroxy-1,4-benzoxazin-3-one), and verbascoside. The concentration of these compounds varied depending on the vegetative state, with lower levels observed during the flowering season. During the initial vegetation stage, DIBOA emerged as the primary compound, gradually diminishing as the plant advanced through its vegetative state. Notably, the concentrations of both DIBOA and verbascoside exhibited a reverse correlation with temperature, rising as temperatures declined. Under elevated temperatures, humidity, and sun exposure, DIBOA is prone to degradation, while verbascoside, a phenylpropanoid, remains relatively stable in these conditions. It was found that the antioxidant activity of the leaves depends mainly on the amount of verbascoside, while the anti-inflammatory potential is primarily attributed to DIBOA. Verbascoside also showed a protective function against the cytotoxicity of the extracts in this study. Tyrosinase activity was affected by the levels of total benzoxazinoids and phenylpropanoids. Overall, this study elucidates the temporal variation of compounds in Acanthus mollis leaves harvested during different seasons, highlighting the importance of the quantification of specific compounds, such as DIBOA, HBOA, and verbascoside, for the selection of the most favorable harvesting season, and providing insights into the effects of temperature and environmental factors on the concentration of these compounds as well as their biological activities.

Abiotic legacies mediate plant–soil feedback during early vegetation succession on rare earth element mine tailings

Abstract An increasing number of studies have shown how feedback interactions between plants and soil can influence primary and secondary succession. However, very little is known about the patterns and mechanisms of such plant–soil feedbacks on stressed mine tailings ecosystem, which can be severely contaminated by a range of toxic elements. In a two‐phase plant–soil feedback experiment based on the rare earth element (REE) mine tailing soil, we investigated biotic (changes in bacterial and fungal communities) and abiotic (changes in chemical properties) legacies of three pioneer grass species, and examined feedback effects of three grasses, two legumes and two woody plants with different root traits. Positive plant–soil feedbacks were found in Miscanthus sinensis, Paspalum thunbergii and Tephrosia candida, and neutral feedbacks were observed in the other four plants. These effects corresponded with an increase in nutrients and total organic carbon, as well as a decrease in acidity and extractable aluminium and REEs. There were less signs of biotic changes in the conditioned tailings. The correlation analysis suggested a relationship between plants' responses to soil legacies and root traits, as well as root economics spectrum. On the mine tailings, acquisitive species with higher specific root length appeared to have greater potential for positive feedback. Synthesis and application. Our study shows that early succession on contaminated rare earth element mine tailings may lead to more positive plant–soil feedback than predicted based on results of non‐contaminated soils, mainly due to the alleviation of abiotic stress in tailings. Therefore, the improvement of specific abiotic soil stress and the trait‐based selection of acquisitive plants should be preferentially considered to promote the primary restoration of degraded land.

Effects of snow removal on seasonal dynamics of soil bacterial community and enzyme activity

High latitude regions are experiencing considerable winter climate change, and reduced snowpack will likely affect soil microbial communities and their function, ultimately altering microbial-mediated biogeochemical cycles. However, the current knowledge on the responses of soil microorganisms to snow cover changes in permafrost ecosystems remains limited. Here, we conducted a 2-year (six periods) snow manipulation experiment comprising ambient snow and snow removal treatments with three replications of each treatment to explore the immediate and legacy effects of snow removal on soil bacterial community and enzyme activity in secondary Betula platyphylla forests in the permafrost region of the Daxing'an Mountains. Generally, bacterial community diversity was not particularly sensitive to the snow removal. Seasonal fluctuations in the relative abundance of dominated bacterial taxa were observed, but snow removal merely exerted a significant impact on the bacterial community structure during the snow melting period and early vegetation growing season within two consecutive years, with a reduction in the relative abundance of Chloroflexi and an increase in the relative abundance of Actinobacteria, and no evidence of cross-season legacy effects was found. Moreover, snow removal significantly altered the soil enzyme activities in the snow stabilization period and snow melting period, with an increase in soil acid phosphatase (ACP) activity of snow melting period and a decrease in polyphenol oxidase (PPO) activity of snow stabilization period as well as β-glucosidase (BG) activity of snow stabilization period and snow melting period, but this effect did not persist into the vegetation growing periods. The seasonal variations in bacterial community and enzyme activity were mostly driven by changes in soil nutrient availability. Overall, our results suggest that soil bacterial communities have rather high resilience and rapid adaptability to snow cover changes in the forest ecosystems in the cold region of the Daxing'an Mountains.

Use of Logs Downed by Wildfires as Erosion Barriers to Encourage Forest Auto-Regeneration: A Case Study in Calabria, Italy

The easy implementation of ecologically-sound remediation measures for the prompt stabilisation of burned areas may be crucial in Mediterranean forest environments. Manual in situ contour redirection of burned felled logs could aid in soil erosion control and facilitate forest self-regeneration. In this study, a plot-scale runoff/sediment yield survey was conducted in Calabria, Italy, within a Mediterranean pine forest that was affected by an extreme wildfire spanning over 15,000 hectares in the summer of 2021. The hydrological response to 24 rainfall events was analysed after one year of monitoring using nine Wischmeier and Smith 20% sloping plots, which were distributed into three plot-blocks representing different conditions (forested, burned with randomly directed fallen logs, and burned with fallen logs manually redirected along contour lines). The post-fire condition (with felled logs in random positions) exhibited a consistent overall increase (approximately four times) in runoff and sediment yield compared to the pre-fire situation. This degradation effect was mitigated by approximately 30% through the manual redirection of burned logs, which promoted early (three to five weeks) vegetation regeneration (including tree emergence) and enhanced coverage as vegetation spread from the log positions. The results obtained so far provide encouraging insights and warrant further research on steeper slopes and complementary aspects (regulatory, biological, mechanical, economic, etc.).

Features of seasonal development of black currant (<i> Ribes nigrum</i> L.) in the Arctic zone of the Russian Federation

Black currant is the most valuable berry crop of the Murmansk Province in terms of both biological properties and adaptive qualities necessary for growing in difficult agroclimatic conditions of the North. Every year, a search is carried out for varieties and forms with the best indicators of winter hardiness, yield, disease resistance and environmental friendliness, in order to identify accessions with the most valuable biological and economic traits. The objects of the present study were 24 cultivars of black currant of different ecological and geographical origin obtained in 2015 from the collection of the N. I. Vavilov All-Russian Research Institute of Plant Genetic Resources (VIR). Studies of the black currant collection were carried out in 2017-2021 at the Polar Experiment Station, a branch of VIR. The care of plants was provided according to the agricultural practices developed for growing berry crops in the Polar Region. The results of five-year phenological observations and assessment of winter hardiness in the studied cultivars showed that the onset of vegetation in all accessions occurred annually in the second decade of May, the onset of flowering in the second decade of June, the onset of maturation in the third decade of July, and the growth of shoots ended in the first decade of September. The studied cultivars were combined into groups according to winter hardiness (highly winter-hardy and winter-hardy), as well as the onset of phenophases (early, medium, late), and of ripening dates (early, mid, and late-ripening). Early vegetation was noted in cultivars ‘Pigmei’, ‘Izyumnaya’, ‘Rita’, ‘Volshebnica’, ‘Vasilisa’, ‘Almiai’, ‘Kriviai’, ‘Mila’, ‘Poklon Borisovoi’. Early ripening of the crop was observed in the cultivars ‘Severnoe Siyanie’ (C), ‘Mila’, ‘Izyumnaya’, ‘Rita’, ‘Kriviai’. The late maturing cultivars are ‘Slavyanka’, ‘Kipiana’, ‘Gratsiya’, ‘Chudnoe Mgnovenie’. The most numerous group is that of mid-ripening cultivars (64 %), followed by the group of early maturing (20 %), and late maturing ones (16 %). All the studied cultivars showed high adaptability to the conditions of the Murmansk Province. They had time enough to form the yield, complete the fruiting and growth of shoots before the onset of frosts. Due to the results of five years of research, they can be recommended for cultivation in the Arctic zone of the Russian Federation.

Assessing primary vegetation recovery from earthquake-induced landslide scars: A real-time kinematic unmanned aerial vehicle approach

Globally, post-disturbance site formation is caused by large-scale natural disturbances. In such areas, it is necessary to restore vegetation rapidly as it regulates the outflow of sediment and water. However, the relationship between post-disturbance site vegetation recovery and environmental factors has not yet been elucidated. This study aimed to estimate the environmental factors affecting early vegetation recovery after large-scale disturbances (i.e., earthquakes). We used a novel analysis of multidimensional high-definition earth surface data derived from real-time kinematic unmanned aerial vehicles (RTK-UAVs) with high positioning accuracy to reveal primary vegetation recovery conditions, accounting for ground surface changes and environmental information of earthquake-induced landslide scars in Japan's boreal forests. A vegetation survey was conducted to understand the species composition and coverage that had recovered from earthquake-induced landslide scar in Japan's boreal forests. The herbaceous species Petasites japonicus subsp. giganteus and the woody introduced species Larix kaempferi were identified as the dominant species that help restore vegetation, with high frequency and plant coverage in the primary succession of the landslide scar. The reproductive characteristics of these pioneer species suggest that they have an advantage for establishment and growth, particularly on landslide scars with substantial topsoil dynamics. An optimal generalized linear model was used, which considered the distance from the vegetation inside and outside the landslide scars, ground surface change, inclination angle, annual amount of solar radiation, and the local region as explanatory variables. The ideal environmental conditions for vegetation recovery are summarized as follows: 1) Maximum biological legacy preserved inside and outside landslide scars. 2) Vegetation recovery expected in stable areas with little erosion and accumulation. 3) Vegetation recovery expected on slopes other than steep slopes or those with extremely high amounts of sunlight. The vegetation recovery conditions and RTK-UAV remote-sensing techniques used in this study can be applied to vegetation restoration zoning plans immediately after a disaster in similar environments.

Early vegetation recovery following a mid to high‐severity fire in the Andean‐Patagonian forests

AbstractA change in fire regimes is occurring worldwide, affecting post‐fire succession. Under this context, there is an increasing need to prioritize restoration areas and focus on their particular goals. To assess the emergent understorey represents the first approximation of post‐fire re‐vegetation, necessary to establish appropriate restoration guidelines. In this study, we aimed to assess the initial post‐fire response in a mid to high‐severity fire in the Andean‐Patagonian forests. We (1) compared plant community structure among fire severities, (2) evaluated the response of plant community structure to the interaction between fire severity and forest type, (3) compared plant composition among fire severity‐forest type categories and (4) evaluated woody species regeneration after fire. We found that the vegetation cover of the lower stratum began to recover early after the fire and to a greater extent in mid than in high severity, whereas the upper stratum was incipient in the mid and nil in high severity. Native species predominated in burned and unburned plots, although they were less in the burned plots. Among the growth form, shrubs and trees were similarly affected by fire, independently of the forest type. Plant community composition varied among most fire severity‐forest type categories. The frequency of woody species regenerated by resprouts and by seeds was lower in burned than unburned plots. These results suggest that although there is an early recovery of vegetation, the high cover of exposed soil and the loss of the upper vegetation stratum may favour erosion and difficult tree establishment. Besides, tree species that only regenerate from seeds will probably not recover naturally. In addition, the presence of exotic species with high invasive risk may need control. Thus, since fire severity and forest type may drive different post‐fire natural recovery scenarios, different restoration actions should be taken to promote resilient systems for the future.

Superior improvement on soil quality by Pennisetum sinese vegetation restoration in the dry-hot valley region, SW China

Vegetation restoration is a good way to improve soil quality and reduce erosion. However, the impact of vegetation restoration on soil quality in the dry-hot valley region has been overlooked for many years. This study aimed to reveal the effects of Pennisetum sinese (PS) and natural vegetation (NV) on soil quality and then to explore the feasibility of introducing PS for the vegetation restoration of the dry-hot valley region. The PS and NV restoration areas deserted land evolving from cultivated land (CL) have been established since 2011. The results showed that the soil properties were obviously improved by PS from the dry to wet seasons, except for the soil available phosphorous. The comprehensive soil quality indexes of the three typical seasons (dry, dry-wet, and wet) were determined by using nonlinear weighted additive (NLWA) based on the total dataset, significant dataset and minimum dataset (MDS). The results indicated that the comprehensive minimum dataset soil quality index (MDS-SQI) of the three typical seasons evaluate soil quality well. The soil quality of PS was significantly greater than that of CL and NV (P < 0.05), as shown by the MDS-SQI. Additionally, PS could maintain a stable soil quality in the three typical seasons, while both CL and NV had obvious fluctuations. In addition, the result of the generalized linear mode suggested that the vegetation type had the greatest impact on the soil quality (44.51 %). Comprehensively, vegetation restoration in the dry-hot valley region has a positive impact on the soil properties and quality. PS is a great candidate species for the early vegetation restoration in the dry-hot valley region. This work provides a reference for vegetation restoration and rational utilization of soil resources in degraded ecosystems in dry-hot valleys and other soil erosion areas.

Analysing the potential of polarimetric decomposition parameters of Sentinel–1 dual-pol SAR data for estimation of rice crop biophysical parameters

The potential of dual-polarization Sentinel–1 polarimetric decomposition parameters i.e., entropy, anisotropy and alpha angle, to monitor the biophysical parameters of rice crop namely, fresh biomass, dry biomass, vegetation water content (VWC) and plant height is investigated in this study. Multi-temporal Sentinel–1A dataset during critical growth stages of rice was considered for regression analysis between the polarimetric decomposition parameters and the biophysical parameters using linear and logarithmic models. The best correlations are obtained at early vegetation stages of the crop i.e. between tillering to booting stages. The maximum R2 value obtained is 0.6 for linear regression of entropy and VWC followed by other biophysical parameters. The correlation of polarimetric decomposition parameters with biophysical parameters is not as high as that of VH backscatter coefficient. Multiple regression using various Sentinel–1 parameters yields a better correlation than regression using individual parameters. The maximum R2 value of 0.765 is obtained for the multiple linear regression for VWC. Multiple regression using the backscatter coefficients and polarimetric decomposition parameters together gives a better correlation than that using only the backscatter coefficients. This indicate that the polarimetric decomposition parameters are sensitive to biophysical parameters and can be used as additional parameters along with the backscatter parameters for rice crop monitoring.

Evoluția fenofazelor de dezvoltare a unor specii de arbuști fructiferi în Republica Moldova

The paper presents the results of the study carried out regarding the development of the phenological phases of plant development of some species of fruit bushes in the Central area of the Republic of Moldova (the period of bud break, flowering and fruit ripening). It was established that the phenological phases of the studied species: raspberry (Rubus idaeus), black currant (Ribes nigrum), red currant (Ribes rubrum) and white currant (Ribes niveum), gooseberry (Ribes grossularia L.), Josta (Ribes x nidigrolaria), blackberry (Rubus caesius L.), sea buckthorn (Hippophae rhamnoides L.), honeysuckle (Lonicera kamtschatica), blueberry (Vaccinium corymbosum L.), dogwood (Viburnum opulus L.), chokeberry (Aronia melanocarpa Elliott), rose hip (Rosa rugosa Thunb), most of them having an early start in vegetation, which coincides with March, flowering takes place in April, and ripening – in June–July. Exceptions are: honeysuckle, with the earliest vegetation (03–09.03), flowering between 30.03 and 26.04 and ripening fruits in the second half of May (19–25.05); raspberries enter vegetation later (09–21.04), bloom on throughout May, and ripening takes place staggered in June, remontant raspberry varieties begin to bloom in July and ripens staggered in August; blackberry, with the latest onset of vegetation and the latest flowering (18.05–04.06), thus avoiding late spring frosts. Ripening takes place in stages at the beginning of July.

Influence of Eucalyptus Plantation on Soil Organic Carbon and Its Fractions in Severely Degraded Soil in Leizhou Peninsula, China

Effective vegetation restoration plays an important role in maintaining and improving soil nutrients and can promote the fixation of soil organic carbon (SOC) and its fractions in degraded soil areas. To understand the influence of Eucalyptus plantation on SOC and its fractions in severely degraded soil in Leizhou Peninsula, China, vegetation restoration with Eucalyptus (RE: Eucalyptus–shrub ES, Eucalyptus–grass EG, and Eucalyptus–Dicranopteris ED) was chosen as the research object, and natural vegetation restoration without Eucalyptus (RNE: shrub S, grass G, and Dicranopteris D) nearby was used as the control group. SOC and its fractions in different vegetation types were compared and analyzed after sample plot surveys and sample determination, and the driving forces of SOC and its fractions were discussed. SOC, dissolved organic carbon (DOC), microbial biomass carbon (MBC), easily oxidized organic carbon (EOC), and particulate organic carbon (POC) in RE were significantly different from those in RNE, increasing by 194.4%, 36.3%, 111.0%, 141.6%, and 289.9%, respectively. The order of SOC, EOC, DOC, MBC, and POC content in RE was ES &gt; EG &gt; ED. SOC and its fractions were positively correlated with leaf litter cover and biomass, and soil organic matter. SOC, total nitrogen, available nitrogen, total phosphorus, available phosphorus, and enzyme activities were negatively correlated with microbial diversity but were not significantly correlated with soil bulk density and microbial richness. Structural equation modeling analysis results showed that soil enzyme activity was a direct driving force of SOC and its fractions. The input of carbon sources from leaf litter and soil properties were indirect factors that affected SOC and its fractions by affecting microbial characteristics and enzyme activities. Thus, planting Eucalyptus in harsh environments, where natural restoration is difficult, can be an effective measure for early vegetation restoration.

О ВОЗМОЖНОСТИ ИСПОЛЬЗОВАНИЯ НЕКОТОРЫХ СОРТОВ ШЕЛКОВИЦЫ ПРИ ВЫКОРМКЕ РАЙОНИРОВАННЫХ ПОРОД ТУТОВОГО ШЕЛКОПРЯДА

Sericulture has been and remains one of the most important branches of agriculture in Uzbekistan, with centuries-old traditions and proven technologies for keeping silkworms. However, global climate changes across the planet and the shift in the development of the national economy trigger the need for search of new methods of the silkworm reproduction and other sources of feed. Repeated attempts to transfer the silkworm to artificial food or other plant species have not proven succesfully. In our research, we have explored a possibility of using non-fodder caterpillars, namely decorative mulberry varieties, for feeding. The findings gained indicate the validity of the weeping mulberry varieties use in the breeding of silkworms in the case of an early start of feeding. Early vegetation of mulberry trees in urban conditions, a large leaf blade and a large green mass of weeping mulberry, make it good for feeding young silkworm caterpillars.

Calibrating ecological indicator values and niche width for a Mediterranean flora

Bioindication of ecological variables such as humidity, temperature or pH by ecological indicator values of plants is a powerful tool for research in plant ecology, e.g. to detect early vegetation changes. Here, we provide a data set of ecological indicator values including niche width for an entire regional flora. We used an extensive data-base with floristic relevés from Southern France to recalibrate indicator values for light (L), temperature (T), continentality (K), air humidity (A), soil moisture (F), pH (R), productivity (N), soil texture (G), soil organic matter content (O) and salinity (S). Values were recalibrated using average values from co-occurring plants, enabling to develop indicator values for species not yet evaluated previously. Recalibrated values are on a continuous scale and we add standard deviation, median, first and third quartile for each indicator value. Linear regression of average indicator values against measured factors showed higher correlation with recalibrated values compared to original indicator values for temperature, pH and nitrogen, and comparable R2 for moisture. Individual indicator systems performed better than a combination and applying different weighting procedures demonstrated the usefulness of inverse variance. We further illustrate graphically how recalibrated values and niche width increase ecological knowledge on plants.