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Investigating the long-term dynamics in the canopy proves to be difficult due to the short observational records of the normalized difference vegetation index (NDVI). To explore the linkage between tree growth, NDVI dynamics and largescale atmospheric circulation in the Greater Khingan Mountain, Northeast China, we established a chronology of Larix gmelinii tree ring width at three elevations (870-920 m, 1,100-1,150 m and 1,270-1,320 m) in the northern foothills of the mountain range. We then calculated the correlations between the tree ring chronologies and NDVI and climate factors, and reconstructed the NDVI time series from June to September 1759-2021 in the region based on the middle-elevation tree ring chronology. The results identify the positive effect of temperature (r = 0.56, p < 0.01) and the negative effect of precipitation (r = 0.44, p < 0.01) in the growing season as the main influencing factors of NDVI for the study period (1981-2019). The 11-year moving average of the reconstructed NDVI series reveals two periods of high canopy vigor (1898-1926 and 2009-2013) and three periods of low canopy vigor (1860-1962, 1882-1888 and 1968-1977) in the last 263 years. These periods correspond to drought events recorded in the historical literature. Wavelet analysis shows that the reconstructed sequences exhibited 11-13, 23-25, and 39-42 years period variations. Integrating this with spatial correlation analysis reveals that tree growth in the Mangui region was impacted by the combined effect of the North Pacific Decadal Oscillation and the North Atlantic Multidecadal Oscillation. The results of this paper provide a reference for the study of vegetation change patterns in the northern foothills of the Greater Khingan Mountains. [ABSTRACT FROM AUTHOR]

Leaf area index (LAI) is an important vegetation leaf structure parameter in forest and agricultural ecosystems. In the paper, we deal with the estimation of leaf area index (LAI) and woody area index (WAI) values in a decline climax spruce forest. The research is conducted on the Červenec research plot at an altitude of 1,420 m a.s.l. in the Western Tatra Mountains in the Jalovecký Creek catchment. We carried out the initial measurements during June, August and October 2023. We estimated the values of the LAI and WAI in the mature living and dead spruce stands using hemispherical photography and HemiView software. LAI and WAI values weren't corrected with clumping index. The average values in the living and dead forest stands were 4.7 and 3.0, respectively. In addition to the estimation of the spruce canopy layer LAI, we measured the LAI values of the understorey vegetation in the living, dead stand and in an open area using the SunScan instrument and the SunData software. The highest LAI values of the understorey in the living stand (1.9), in the dead stand (5.3) and in an open area (2.9) were obtained in August, when the vegetation was fully leafy. On the other hand, the lowest LAI values in the understorey were reached in the living stand (1.2) and in an open area (1.8) in October, when the vegetation was already without leaves. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Geography & Environmental Management is the property of Al-Farabi Kazakh National University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Hydrodynamic as well as balance analysis of flow or discharge conditions in surface streams cannot be done without knowledge of the basic hydraulic parameters of the flow. These are, for example, the bathymetry of the water body, the distribution of velocities in the transverse and longitudinal directions, roughness, etc. To determine the value of discharge in a given cross section profile, it is necessary to know the discharge area and the velocity profile. There are several devices and methods for measuring these quantities. Recently, devices based on the application of the Doppler principle are increasingly being used to determine velocity profiles and discharges in field conditions. In ideal conditions, the use of such devices is very effective, but in the case of the presence of aquatic vegetation below the water surface, a problem may arise. The paper analyses the accuracy of determining the discharge area in a lowland stream with a small longitudinal slope with the presence of aquatic vegetation using the Acoustic Doppler Current Profiler (ADCP) device (River Surveyor, SonTek/a Xylem brand). The results of the analysis show that for such cases, this method shows limitations, the extent of which depends on the used sub-method (Bottom Track or Vertical Beam), as well as on the amount of aquatic vegetation below the water surface. [ABSTRACT FROM AUTHOR]

Forest vegetation is an important component of forest ecosystems, contributing to terrestrial plant diversity while also providing a variety of ecological services. In managed landscapes, plantations emerge as dominant kinds after stand-replacing disturbances. However, the dynamics of vegetation cover, diversity, and composition in plantation forests remains poorly understood in the subtropical region. Our study recorded a rich floral diversity with 173 angiosperm species, characterized by varying life forms and distinct flowering phenology. The uneven distribution of species across families demonstrated the complexity of the ecosystem, with Poaceae being dominant. Diversity patterns among different plantation types varied, with Dalbergia sissoo and Populus nigra plantations exhibiting higher species richness and diversity. Conversely, Eucalyptus camaldulensis and Morus alba plantations displayed lower diversity, emphasizing the influence of plantation type on biodiversity. Non-metric multidimensional scaling (nMDS) and PERMANOVA analyses revealed significant dissimilarity patterns of vegetation composition. Indicator species analysis identified unique compositions within each plantation type, emphasizing the importance of conserving specific types to protect indicator species and maintained ecological distinctiveness. Canonical Correspondence Analysis (CCA) demonstrated that road accessibility, stem cutting, and fire significantly influenced plant distribution patterns. The present research underscored the importance of considering plantation type in forest management for biodiversity conservation and highlighted the environmental variables' influence on the formation of plant communities. These results provided major implications for sustainable forest management and conservation efforts in tropical regions. [ABSTRACT FROM AUTHOR]

Vegetation plays an essential role in terrestrial carbon balance and climate systems. Exploring and understanding relationships between vegetation dynamics and climate changes in Southwest China is of great significance for ecological environment conservation. Nonlinear relationships between vegetation and natural factors are extraordinarily complex in Southwest China with complicated topographic conditions and changeable climatic characteristics. Considering the complex nonlinear relationships, the Random Forest (RF) and an integration of Convolutional Neural Networks and Long Short-Term Memory network (CNN-LSTM) were used with multi-source data from 2000-2020. Performance of two models were compared with precision indicators, and influence of topographic and hydro-climatic factors on vegetation was quantified based on the optimal models. Results revealed that the Normalized Difference Vegetation Index had a significant negative correlation with elevation and a positive correlation with land surface temperature and evapotranspiration. According to precision indicators, the RF model (RF3) built with longitude, latitude, elevation, slope, temperature, precipitation, evapotranspiration and surface solar radiation as inputs outperformed other models. Relative importance of the eight natural factors was quantified based on the RF3, and results indicated that elevation, temperature and evapotranspiration were major factors that influenced vegetation growth. Responses of vegetation toward climatic variables exhibited significant seasonal change, and there were different decisive factors, which influenced vegetation growth in forests, grasslands and croplands. [ABSTRACT FROM AUTHOR]

Seasonal factors such as temperature, solar UV-light intensity, and daylight length can induce changes in the water quality properties and, hence, the nutritional compositions of plants. This comparative study was carried out for the consecutive four (4) seasons (winter, spring, summer, and autumn) to determine the influence of seasonal variations on the 50% inhibitory concentration (IC50), total antioxidant capacity (TAC), total phenolics content (TPC), and total flavonoids content (TPC) of the red chili fruit (RCF), red tomato fruit (RTF), green leafy spinach (GLS), and green leafy lettuce (GLL) collected from a coupled commercial aquaponics system. The IC50, TAC, TPC, and TFC concentration levels indicated a significant (P<0.05) difference in the summer compared with the winter, spring, and autumn. The RCF extract indicated the lowest IC50, thus greater scavenging power in comparison to RTF, GLS, and GLL extracts. Similarly, the RCF showed the highest TAC and TPC, while the GLL showed the highest TFC. In this study, variations in seasons have induced changes in the IC50, TAC, TPC, and TFC concentration levels of the RCF, RTF, GLS, and GLL extracts. [ABSTRACT FROM AUTHOR]

Rhizobia induces nitrogen-fixing nodules in legumes used in agricultural production, providing a direct source of combined nitrogen to leguminous crops. Small peptides, such as CLAVATA3/EMBRYO SURROUNDING REGION peptides (CLE), are known to regulate the formation and development of nitrogen-fixing nodules in legumes. Root meristem growth factor (RGF) peptides from Medicago truncatula not only regulate root development but also modulate nodulation symbiosis with Sinorhizobium meliloti. However, the impact of RGF peptides from one leguminous species on the others remains unclear. In this study, we investigate the effects of the RGF family peptide MtRGF6p from M. truncatula on nodulation symbiosis and root development in Lotus japonicus. The MtRGF6 gene is predominantly expressed in the root nodules of M. truncatula and shows low identity with RGF homologous genes from L. japonicus. The gene promoter is active in the primordia of root nodules and lateral roots, as well as in young nodules and roots, and the meristem, infection, and nitrogen-fixing regions of the mature nodule. Chemically synthesized MtRGF6p promoted primary root growth in M. truncatula but suppressed the growth of L. japonicus primary roots. The peptide negatively affected the initiation of nodule primordia, the formation of infection threads, and nodulation in both legumes, with a low dosage showing effects on L. japonicus compared to M. truncatula. These results suggest that the MtRGF6 peptide from M. truncatula may serve as an inter-species signal affecting the root organ development of L. japonicus. [ABSTRACT FROM AUTHOR]

Human activities and industrialization have significantly increased soil nutrients, such as nitrogen (N) and phosphorus (P), profoundly impacting the composition and structure of plant community, as well as the ecosystem functions, especially in nutrient-limited ecosystems. However, as the key propagule pool of perennial grasslands, how belowground bud bank and its relationship with aboveground vegetation respond to short-term changes in soil nutrients was still unclear. In this study, we conducted a short-term (2021-2022) soil fertilization experiment with N addition (10 g N m-2 yr-1) and P addition (5 g N m-2 yr-1) in the meadow steppe of Inner Mongolia, China, to explore the responses of belowground bud bank, aboveground shoot population and their relationships (represented by the ratio of bud to shoot density-meristem limitation index (MLI)) for the whole community and three plant functional groups (perennial rhizomatous grasses-PR, perennial bunchgrasses-PB, and perennial forbs-PF) to nutrient addition. The short-term nutrient addition had no significant influences on belowground bud density, aboveground shoot density, and MLI of the whole plant community. Plant functional groups showed different responses to soil fertilization. Specifically, N addition significantly increased the bud density and shoot density of PR, especially in combination with P addition. N addition reduced the shoot density of PF but had no influence on its bud density and MLI. Nutrient addition had significant effects on the three indicators of PB. Our study indicates that the belowground bud bank and its relationship with aboveground vegetation in temperate meadow steppe are insensitive to short-term soil fertilization, but plant functional groups exhibit specific responses in terms of population regeneration, which implies that plant community composition and ecosystem functions will be changed under the ongoing global change. [ABSTRACT FROM AUTHOR]

The dynamics and complexity of plant communities influence the diversity and distribution of animals in various environments. Coleoptera are the most diverse group of insects and are valued as monitoring and environmental assessment tools. However, their diversity and dynamics in these high-altitude environments are poorly known. Using pitfall traps and suction sampling, we collected beetles to study their community responses to changes in different vegetation heterogeneities (low, intermediate, and high). The heterogeneity gradient was determined by considering the dominant plant species in each habitat, the percentage of vegetation coverage, and the percentage of vertical strata. Guild's responses to vegetation heterogeneity were analysed in conjunction with the patterns of alpha and beta diversity in beetles. Representatives of 41 species/morphospecies of beetles, 16 families, and four guilds were reported. Significant variations were observed in guild composition and alpha and beta diversity, especially between high and low vegetation heterogeneity habitats. The significant species turnover between sites is the main factor responsible for the high beta diversity, supporting considerable habitat heterogeneity within these environments. Phytophagous, detritivorous, necrophagous, and predatory beetles exhibited distinct responses to the vegetation's heterogeneity. This suggests that every habitat under investigation possesses a distinct structure of beetle communities. Predators were important in habitats with more diverse vegetation, while phytophagous were important in the most homogeneous ones. Beetle communities in the Puna and Altos Andes of Salta province respond positively to vegetation heterogeneity, which plays a crucial role in determining the composition of small-scale beetle communities in arid high-altitude environments. [ABSTRACT FROM AUTHOR]

There is a well-known phenomenon in tree crops known as "biennial bearing," in which the fruit-bearing increases or de- creases every other year. Synchronization of biennial bearing has been more prevalent in olives of the Eastern Mediterranean region, which includes Jordan and Syria, rather than fluctuations associated with rainfall and other climatic conditions. This synchronization phenomenon is thought to have been accepted in the region since the time of ancient civilizations, but modern science has not been able to elucidate its mechanism. On the other hand, the biennial bearing and synchronization phenomena have significantly been disrupted since the beginning of the 21st century. The disappearance of biennial bearing and the reversal of synchronization can be observed since 2008 in Syria and 2015 in Jordan. These periods coincide with when the problems of refugee inflows into Syria due to the Iraq War and into Jordan due to the Syrian Civil War became apparent, respectively. Therefore, this study examines the hypothesis that social, political, and economic factors, which have been neglected in agronomy, have substantially influenced those phenomena in olive production. Field surveys and experiments are conducted in the Irbid governorate of Jordan, where olive production is the most dominant agricultural activity, with significant labor and consumer population inflows from the bordering parts of Syria. [ABSTRACT FROM AUTHOR]

The aim of the article. This article highlights the significance of forest cover as an important indicator of the state of the environment. It discusses the findings of the Food and Agriculture Organization of the United Nations (FAO) Forest Resources Assessment (FRA) 2020 report, which states that the world's forest area has decreased by 178 million hectares since 1990. The case study of Volyn region shows how cloud processing and vegetation classification can help quantify forest dynamics from 2000 to 2020, allowing local authorities and decision makers to monitor and analyze trends in near real time. Overall, this work provides insights into the importance of monitoring forest dynamics and the potential for remote sensing technology to facilitate this process. Data & Methods. Remote sensing is an effective tool for monitoring forest ecology and management, and Google Earth Engine (GEE) is an online platform that combines data from various agencies to analyze environmental data. The article presents a case study of the Volyn region and how cloud processing and vegetation classification were used to assess forest dynamics from 2000 to 2020. The study used data from Landsat 7 Collection 1 Tier 1 composites and the CART algorithm for binary decision tree building. The study was based on information provided by the Main Department of Statistics in the Volyn region on the area of forests and areas where logging was carried out during the specified period. Research results. It is interesting to note that despite the decrease in logging activities, there is an increase in forest cover loss within forest ranges. This could be due to various reasons, such as illegal logging or natural disturbances like fires or disease outbreaks. The use of machine learning methods like CART classification can help to identify and monitor these changes, which can then be used to inform policy decisions and management practices to reduce forest cover loss. In general, in the Volyn region, there is a gradual decrease in the areas where various kinds of logging are carried out from 524 km² in 2003 to 239 km² in 2020. In contrast, forest cover loss within forest ranges increased rapidly from 37.85 km² in 2015 to 84.01 km² in 2017 and beyond from 5.53 km² to 10.80 km² in 2015 and 2017 respectively. In this study, the accuracy assessment was performed using 30% of the control points obtained initially, based on data on the reliability of the land cover. The manufacturer's accuracy and user accuracy were calculated to evaluate error omissions and possibilities of a pixel being categorized in a certain category. The spatial resolution of Landsat 7 data used in this study was 30 m, with a minimum calculation area of 0.337 hectares. The overall accuracy and the coefficient κ are the most representative measures of accuracy, with an average accuracy of classification of OAav=98.82% and kav=0.9764. [ABSTRACT FROM AUTHOR]

This article explores the biology and cultivation of the Hyacinthus Orientalis species, emphasizing the importance of flowers in human life. The study focuses on the characteristics and quality of three varieties of Hyacinthus Orientalis, including measurements such as plant height, flower length, and storage duration. The findings indicate that the storage time of cut flowers ranges from 8 to 12 days, and the number of flowers on the stem can vary from 8 to 23. The article provides descriptions of two specific varieties, Blue Jacket and Pink Pearl, including their preferred growing conditions and flowering periods. It also discusses the biology of hyacinths and their response to technological measures. The document provides research data on the number of petals and storage time duration of three varieties of Hyacinthus orientalis flowers, suggesting that introducing varieties with many flowers and long storage times would be beneficial. [Extracted from the article]

On September 4, 2023, Thessaly, Greece, underwent a catastrophic flood due to Medicane Daniel. Extreme rainfall, ranging from 305 mm to 1096 mm between 4 and 12 September, caused extensive damage to the infrastructure, agriculture and houses. Seventeen casualties were recorded. This study is aimed at using radar data from earth observation satellites to detect the inundated areas and evaluate the impact of the flood. Sentinel images were acquired from Copernicus Open Acess Hub For 7, 10, 13, and 19 September, 2023, along with a CORINE Land use/Land cover map. Processing the satellite images involved several steps, including their calibration, noise removal, filtering, and polarization adjustments. Flooded areas were quantified for the specified dates, thereby revealing substantial coverage of the land. The damage assessment focused on irrigated and non-irrigated land and pasture areas, highlighting the impact's severity. The highest impact was noticed on September 7 in irrigated land (95.62%). The second phase incorporated the Flood Water Depth Estimation Tool (FwDET) to estimate the floodwater depths and reveal the maximum depths near riverbanks. The maximum floodwater depth was also noticed on September 7 and reached 9.49 m. This study employed advanced remote sensing and GIS techniques, allowing for a rapid estimation of flood characteristics and assessment of Medicine Daniel's damage to the Thessaly prefecture from September 4 to 12, 2023. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Forestry Society of Croatia / Sumarski List Hrvatskoga Sumarskoga Drustva is the property of Forestry Society of Croatia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)