Ulmus Pumila Research Articles

The current state of Ulmus pumila L. in shelterbelts dry steppe zone of the Republic of Khakassia

One of the most effective and cheapest ways to reduce environmental stress on arable land is forest shelterbelts. Elm (Ulmus pumila L.) is the main tree species used in field-protective afforestation in the dry steppe zone of the Republic of Khakassia. The studies were carried out in field-protective forest belts of different planting methods, consisting of Ulmus pumila, growing in the Koibal steppe of the Beisky district of the Republic of Khakassia. Here, using modern techniques, temporary trial plots were laid. The aim of the study was to study the current state of life of elm shelterbelts in the dry steppe zone of the Republic of Khakassia. The features of growth, preservation, natural regeneration and sanitary condition of elm forests on trial plots are analyzed depending on the planting methods and the design of forest plantations growing on underdeveloped chestnut sandy loamy soil. It has been established that the best condition of elm trees (1.7-2.2 points) 31 years after planting is noted in forest belts with a checkerboard arrangement of trees, and the worst (2.8-3.2 points) is in forest belts with row plant placement, which is necessary take into account when creating a new generation of shelterbelts.

Особенности роста вяза приземистого на бурых почвах Астраханской полупустыни

The article presents the current state assessment and suggests the methods for additional moisture supply of soils under stable tree plantations of Siberian elm (Ulmus pumila L.) on brown soils of semi-desert. The research area belongs to the arid zone. This is a treeless zone of dry steppe and semi-desert, where about 1,000 ha of plantations with a predominance of elm of different species have been planted since 1949–1953: shade clumps, pasture protection strips, massifs, separated forest stands. The soils are brown desert-steppe alkaline sandy loam and light clay-loam in combination with solonetz (10 %). Siberian elm stands form plantations of different ages and for different purposes. The research is based on biomonitoring materials and field experiments using standard forest inventory techniques. Test sites of a rectangular shape with an area of 0.4 ha were laid out in order to study the Siberian elm stands. We described in detail the location of the test sites, the soil composition thereon, and gave a comprehensive assessment of the growth and durability of the plantations. It is shown that the stand state is determined by 2 sets of factors: zonal-edaphic and pastoraleconomic. Viable stands of Siberian elm at the age of 57–64 have been preserved on sandy loam and dark-colored soils located in micro- and inter-hill depressions. The dynamics of soil moisture under plantations is largely independent of the tree location method. Satisfactory indicators of growth and durability of plantations depend on the level of availability of soil moisture and the degree of its salinity. The moisture supply of soils under elm plantations can be increased by using melt water runoff in hollows and micro-depressions and increasing the growing space of a tree to 25 m2. Formed elm plantations respond positively to the presence of resting animals. The “alliance” relationship between the stand and livestock does not arise immediately, but rather from a certain age of the stand and the moment it forms a certain structure of the tree layer, which should be provided by forest cultivation and silvicultural measures in conjunction with the regulation of pasture load. There is a positive effect of resting animals at the appropriate load on the growth, state and durability of the Siberian elm stands.

Contrasting patterns of variation in foliar pH between a woody species and an herbaceous species along a 3300 km water availability gradient in China

Water availability is one of the most pertinent factors affected by global change that regulates plant functional traits. Foliar pH is a newly recognized predictive functional trait that is indicative of plant physiological processes, carbon and nutrient cycling and plant survival under environmental change. In general, foliar pH is directly related to soil pH, while soil pH is directly related to water availability. Thus, biogeographic variation in foliar pH across water availability gradients is expected. This study investigated the foliar pH of common species (woody plant: Ulmus pumila; herb: Setaria viridis) along a 3300 km transect characterized by a water availability gradient from northwestern to southeastern China. The results revealed that the foliar pH of U. pumila significantly decreased as the water availability increased, but for S. viridis, a quadratic curve with the knee point at a humidity index (HI) of 0.63 was observed, indicating different responses of foliar pH to variations in water availability between these common species. The mean foliar pH of S. viridis was significantly higher than that of U. pumila, especially in arid and semiarid regions. The soil pH, soil water stress coefficient (Ksoil) and HI were the three most influential factors on the foliar pH of U. pumila. For S. viridis, the variation in foliar pH was attributed to mean annual temperature (MAT), soil pH, HI, Ksoil, mean annual precipitation (MAP) and the precipitation of the wettest quarter. Our study revealed contrasting patterns of variation in foliar pH between woody species and herbs, suggesting that we should discriminate plant functional types in large-scale models when predicting plant responses to global change.

Stomatal opening ratio mediates trait coordinating network adaptation to environmental gradients.

A trait coordination network is constructed through intercorrelations of functional traits, which reflect trait-based adaptive strategies. However, little is known about how these networks change across spatial scales, and what drivers and mechanisms mediate this change. This study bridges that gap by integrating functional traits related to plant carbon gain and water economy into the coordination network of Siberian elm (Ulmus pumila), a eurybiont that survives along a 3800 km environmental gradient from humid forest to arid desert. Our results demonstrated that both stomatal density and stomatal size reached a physiological threshold at which adjustments in these traits were not sufficient to cope with the increased environmental stress. Network analysis further revealed that the mechanism for overcoming this threshold, the stomatal opening ratio, gratio , was represented by the highest values for centrality across different spatial scales, and therefore mediated the changes in the trait coordination network along environmental gradients. The mediating roles manifested as creating the highest maximum theoretical stomatal conductance (gsmax ) but lowest possible gratio for pathogen defense in humid regions, while maintaining the gratio 'sweet spot' (c. 20% in this region) for highest water use efficiency in semihumid regions, and having the lowest gsmax and highest gratio for gas exchange and leaf cooling in arid regions. These results suggested that the stomatal traits related to control of stomatal movement play fundamental roles in balancing gas exchange, leaf cooling, embolism resistance and pathogen defense. These insights will allow more accurate model parameterization for different regions, and therefore better predictions of species' responses to global change.

Selection and evaluation of suitable tree species in dry and dusty mining areas of Northwest China

To select drought-resistant and dust-tolerant native species suitable for use in the rehabilitation of major coal bases in northwest China, nine tree species were identified for growth rates, biomass, harm index, and physiological indices under drought and high dust stress conditions. The results showed that, in the dust resistance index system, the order was Caragana korshinskii > Amorpha fruticosa > Sabina vulgaris > Hedysarum scoparium > Tamarix chinensis > Ammopiptanthus mongolicus > Ulmus pumila > Caryopteris mongholica > Elaeagnus angustifolia. In a comprehensive drought and dust resistance index system, 14 indices (such as shoot length, stomatal conductance, and peroxidase) had the larger weight indices. The drought and dust resistance order of the tree species was Caragana korshinskii > Ulmus pumila > Amorpha fruticosa > Sabina vulgaris > Caryopteris mongholica > Ammopiptanthus mongolicus > Hedysarum scoparium > Tamarix chinensis > Elaeagnus angustifolia. This study provides effective strategies and references for selecting suitable tree species for arid mining sites in China, and also for the revegetation of coal mining sites worldwide.

Comparative Transcriptome Analysis Reveals Candidate Genes and Pathways for Potential Branch Growth in Elm (Ulmus pumila) Cultivars.

Simple SummaryElm (Ulmus pumila) is a strong essential wood, and it is widely used in cabinets, sculptures, and ship making. In the present study, phenotypic and comparative transcriptomic analyses were performed in elm fast- (UGu17 and UZuantian) and slow-growing cultivars (U81-07 and U82-39). Phenotypic observation showed that the thickness of secondary xylem of 2-year-old fast-growing branches was greater compared with slow-growing cultivars. Comparative transcriptome analysis predicted that many pathways were involved in vascular development and transcriptional regulation in elm, such as “plant-type secondary cell wall biogenesis”, “cell wall thickening”, and “phenylpropanoid biosynthesis”. NAC domain transcriptional factors (TFs) and their master regulators, cellulose synthase catalytic subunits (CESAs), xylan synthesis, and secondary wall thickness were presumed to function in the thickening mechanism of elm branches. Our results indicated that the general phenylpropanoid pathway and lignin metabolism had vital functions in the growth of elm branches.Wood plays a vital role in human life. It is important to study the thickening mechanism of tree branches and explore the mechanism of wood formation. Elm (Ulmus pumila) is a strong essential wood, and it is widely used in cabinets, sculptures, and ship making. In the present study, phenotypic and comparative transcriptomic analyses were performed in U. pumila fast- (UGu17 and UZuantian) and slow-growing cultivars (U81-07 and U82-39). Phenotypic observation showed that the thickness of secondary xylem of 2-year-old fast-growing branches was greater compared with slow-growing cultivars. A total of 9367 (up = 4363, down = 5004), 7159 (3413/3746), 7436 (3566/3870), and 5707 (2719/2988) differentially expressed genes (DEGs) were identified between fast- and slow-growing cultivars. Moreover, GO and KEGG enrichment analyses predicted that many pathways were involved in vascular development and transcriptional regulation in elm, such as “plant-type secondary cell wall biogenesis”, “cell wall thickening”, and “phenylpropanoid biosynthesis”. NAC domain transcriptional factors (TFs) and their master regulators (VND1/MYB26), cellulose synthase catalytic subunits (CESAs) (such as IRX5/IRX3/IRX1), xylan synthesis, and secondary wall thickness (such as IRX9/IRX10/IRX8) were supposed to function in the thickening mechanism of elm branches. Our results indicated that the general phenylpropanoid pathway (such as PAL/C4H/4CL) and lignin metabolism (such as HCL/CSE/CCoAOMT/CCR/F5H) had vital functions in the growth of elm branches. Our transcriptome data were consistent with molecular results for branch thickening in elm cultivars.

Plant Ontogeny Strongly Influences SO2 Stress Resistance in Landscape Tree Species Leaf Functional Traits

Sulfur dioxide (SO2) is a major atmospheric pollutant and abiotic stressor. Although physiological studies on abiotic stressors have focused on fully expanded leaves, the resistance of leaf functional traits to SO2 during individual leaf development has not been studied. Thus, this study aimed to conduct SO2 static artificial fumigation experiments to evaluate changes in leaf functional traits and resistance to SO2 for three common landscape tree species (Syringa oblata Lindl. (S. oblata), Prunus cerasifera var. atropurpurea Jack. (P. cerasifera), and Ulmus pumila ‘Jinye’ (U. pumila)) in Changchun City and ontogeny under SO2 stress. Samples were collected on three days in autumn (1 September, 9 September, and 19 September 2019) for two different leaf stages (10 days and 40 days). In addition, remote sensing data were combined to explore the resistance mechanisms of broadleaf forests to different SO2 concentration classes during different seasons on a large scale. The results showed that the chlorophyll content, leaf temperature, green-peak reflectance, and Fv/Fm (maximal photochemical efficiency) at 10 days were significantly lower than that at 40 days, regardless of sampling date or SO2 concentration. Additionally, in general the SO2 resistance for 10 days leaves was consistently smaller than those for 40 days leaves in 3 tree species. On 9 September, 10 days leaves of the three tree species showed different leaf resistance performances under different SO2 concentrations in the order: P. cerasifera > S. oblata > U. pumila. Lastly, the extent of resistance decreased with increasing ρ(SO2) classes in different seasons, and the SO2 resistance was affected by season. We conclude that mature leaves are more resistant to SO2 stress than young leaves are. These results will provide scientific guidance on artificial plant community construction and prevention of future vegetation degradation.

Yield Performance of Woody Crops on Marginal Agricultural Land in Latvia, Spain and Ukraine

Agricultural land abandonment due to biophysical and socioeconomic constraints is increasing across Europe. Meanwhile there is also an increase in bioenergy demand. This study assessed woody crop performance on several relevant types of marginal agricultural land in Europe, based on field experiments in Latvia, Spain and Ukraine. In Latvia, hybrid aspen was more productive than birch and alder species, and after eight years produced 4.8 Mg ha−1 y−1 on stony soil with sandy loam texture, when best clone and treatment combination was selected. In Spain, Siberian elm produced up to 7.1 Mg ha−1 y−1 on stony, sandy soil with low organic carbon content after three triennial rotations. In Ukraine, willow plantations produced a maximum of 10.8 Mg ha−1 y−1 on a soil with low soil organic carbon after second triennial rotation. The productivity was higher when management practices were optimized specifically to address the limiting factors of a site. Longer rotations and lower biomass yields compared to high-value land can be expected when woody crops are grown on similar marginal agricultural land shown in this study. Future studies should start here and investigate to what extent woody crops can contribute to rural development under these conditions.

Tall trees drive the nest-site selection of wild Crested Ibis Nipponia nippon

Summary Understanding how birds select breeding sites plays an important role in habitat protection, especially for the conservation of endangered species. With the increase in population size of the endangered Crested Ibis Nipponia nippon, its distribution range has expanded from mountain areas to plains located outside protected areas, representing a new challenge for conservation of the species. Identifying the current nesting habitat requirements is thus needed and can provide valuable information for the planning of new nature reserves. In this research, we surveyed a total of 117 nests across the whole distribution range from 2015 to 2019. We used generalized linear mixed-effects models to assess nesting preferences of the Crested Ibis in the wild. Results showed that in mountain areas, Masson pines Pinus massoniana were preferred (64.6%), whereas elms Ulmus pumila (44.9%) and aspens Populus davidiana (40.6%) were used more frequently lower down, probably because of their higher availability. In both mountain areas and plains the ibises selected tall nesting trees with larger diameter at breast height and preferred nesting rather high above ground, especially in plains where taller trees provided higher suitable nesting positions. The ibises also preferred nesting close to tree trunks, especially in mountain areas, probably for more safety from collapsing. Furthermore, in mountain areas, slope and distance to path had positive effects on nesting occurrence, and understorey coverage was avoided by nesting ibises, while these variables had little impact in plains. Our results indicate that, despite their range expansion, Crested Ibises rely on very specific habitat characteristics for nesting. We suggest relatively tall trees like elms and aspens should be preserved in plains. In addition, we highlight how selection patterns of Crested Ibises may vary, and that such variation should be addressed in conservation planning, especially in future reintroduction.

Electricity as an effective weed control tool in non‐crop areas

AbstractWhile weed management is often thought of as an agricultural issue, weeds are also problematic for homeowners, public space managers and utilities. In these situations, weeds are typically hand‐pulled, mechanically treated or managed via herbicides. Hand pulling and mechanical treatments are labour‐intensive, and all control methods may have unintended off‐target impacts, necessitating new alternatives for weed control. We have developed a method of using electricity to effectively manage unwanted plants. A series of experiments was conducted with the aim of developing operating protocols with consideration to specific scenarios: we tested a system on Morus alba (mulberry) and Ulmus pumila saplings, determined the response of Tamarix spp. (tamarisk) to different electricity doses, evaluated electricity as pre‐emergent weed control in xeriscaping, and tested the ability of electricity to prevent climbing growth by the vine Convolvulus arvensis (field bindweed). Tests on M. alba and U. pumila demonstrated that low doses of electricity applied over several days are effective in killing trees up to 20 cm in diameter. The Tamarix experiment showed that the plants displayed typical dose–response characteristics with higher doses leading to less plant growth. Results of the pre‐emergent weed control experiment demonstrated the excellent ability of electricity to prevent weed growth, with treated plots having a mean weed cover of 4% compared to 94% in control plots after 4 months. Finally, electricity was shown to be 100% effective in preventing C. arvensis from climbing poles. Our results indicate that electricity is a viable alternative to manual, mechanical or chemical methods for small tree control, pre‐emergent weed control in xeriscaping, and prevention of climbing weeds.

Cytology, transcriptomics, and mass spectrometry imaging reveal changes in late-maturation elm (Ulmus pumila) seeds

During seed maturation, the seed deposits storage compounds (starches, oils, and proteins), synthesizes defense compounds, produces a seed coat, initiates embryo dormancy, and becomes desiccated. During the late-maturation stage, seed storage compound contents and compositions change dramatically. Although maturation has been extensively studied in model species and crops, it remains less well characterized in woody perennial plants. In this study, we conducted morphological and cytological observations, transcriptome profiling, and chemical constituent analysis of elm (Ulmus pumila L.) seeds during the late-maturation stage. Light and electron microscopy revealed that closely packed yet discrete lipid bodies frequently surrounded the densely stained protein bodies, and the protein bodies became irregular or even partially disintegrated at the end of seed development. RNA-seq detected substantial transcriptome changes during the late-maturation stage, and pathway enrichment analysis showed that the differentially expressed genes were associated with phenylpropanoid biosynthesis, starch and sucrose metabolism, plant–pathogen interactions, and hormone signal transduction. Furthermore, we used mass spectrometry imaging to detect the relative intensity and spatial distribution of fatty acids, phospholipids, and waxes in elm seeds. Our findings provide a framework for understanding the changes in cytological features and chemical composition during the final stage of elm seed development, and a detailed reference for seed development in woody plants.

Condition and growth of pedunculate oak (Quercus robur L.) in irrigated forest belts of Saratov Trans-Volga steppe

The research aim was to establish the regularities of condition and growth of pedunculate oak (Quercus robur L.) in the irrigated forest belts in the steppe of Saratov Trans-Volga Region. The study object is a system of forest shelter belts under conditions of irrigation of dark chestnut soils of Saratov Trans-Volga steppe with tree species of the main and accompanying purpose - pedunculate oak, lanceolate ash (Fracsinus lanceolata L.) and squat elm (Ulmus pumila L.). The research in the field and materials processing were carried out in accordance with the methodology of specialized research institutes and leading scientists in the field of agroforestry. Forest belts located on agricultural land protect crops from the negative effects of drought and dry winds, optimize snow distribution in winter and irrigation regimes for crops during the growing season, and increase the crops productivity. Irrigation has the most important positive effect on growth and condition of tree species in forest belts and, as a result, on durability and reforestation efficiency of forest belts. The studies have shown that the average height and diameter of oak in the. irrigated forest belts mixed with different species are higher than those without irrigation by 15-26% and 34-39%, respectively. The oak growth in height in irrigated areas of forest belts exceeds its growth in height in areas of forest belts without irrigation by 1.5 times. The vital condition of oak in the irrigated forest belts is characterized by the prevalence of “slightly oppressed” (48%) and “healthy” oak trees (40%).

Dynamic physiological and transcriptome changes reveal a potential relationship between the circadian clock and salt stress response in Ulmus pumila.

Despite the important role the circadian clock plays in numerous critical physiological responses in plants, such as hypocotyl elongation, leaf movement, stomatal opening, flowering, and stress responses, there have been no investigations into the effect of the circadian clock on physiological and transcriptional networks under salt stress. Ulmus pumila L. has been reported to tolerate 100-150mM NaCl treatment. We measured the diurnal variation in photosynthesis and chlorophyll fluorescence parameters and performed a time-course transcriptome analysis of 2-years-old U. pumila seedlings under salt treatment to dissect the physiological regulation and potential relationship between the circadian network and the salt stress response. Seedlings in 150mM NaCl treatment exhibited salt-induced physiological enhancement compared to the control group. A total of 7009 differentially expressed unigenes (DEGs) were identified under salt stress, of which 16 DEGs were identified as circadian rhythm-related DEGs (crDEGs). Further analysis of dynamic expression changes revealed that DEGs involved in four crucial pathways-photosynthesis, thiamine metabolism, abscisic acid synthesis and metabolism, and the hormone-MAPK signal crosstalk pathway-are closely related to the circadian clock. Finally, we constructed a co-expression network between the circadian clock and these four crucial pathways. Our results help shed light on the molecular link between the circadian network and salt stress tolerance in U. pumila.

Ulmus pumila (dwarf elm)

This datasheet on Ulmus pumila covers Identity, Overview, Distribution, Biology & Ecology, Environmental Requirements, Uses, Management, Further Information.

АНАЛИЗ ЖИЗНЕСПОСОБНОСТИ ДРЕВЕСНЫХ ВИДОВ В ЗАЩИТНЫХ ЛЕСНЫХ ПОЛОСАХ АРИДНОЙ ТЕРРИТОРИИ ВОЛГОГРАДСКОЙ ОБЛАСТИ

To solve scientific and practical problems in the field of agroforestry of arid territories, it is particularly relevant to preserve protective forest plantations of artificial origin on agricultural lands, since they have a positive impact on the yield of agricultural crops. Increasing the resistance of tree plantations to unfavorable natural and climatic factors of the arid zone, increasing the period of the reclamation effect on soil fertility, improving the ecological state of agrarian landscapes is a priority task in agroforestry reclamation measures. Created in the middle of the XX century, without deep analysis of soil and geological conditions, without taking into account salt resistance and proper care for a long time, forest strips began to degrade and lost their basic functionality. Intended primarily to mitigate the harsh climate of the Volgograd region, forest strips have also lost their aesthetic appeal. Taking into account the considerable experience of artificial afforestation in the arid zone and in the conditions of the dry steppe, there is still no clear scientific justification for the creation of sustainable protective forest plantations that can provide an appropriate reclamation effect aimed at reducing wind speed, improving the microclimate of fields and stabilizing water and wind erosion. In order for agroforestry in the region to have the calculated effect, an analysis of tree plantations in protective forest strips was carried out, since it is necessary to improve the range of tree and shrub plantations that are used in the creation of artificial forest plantations. The heat resistance and winter hardiness of seeds of the most common tree plantations (such as Quercus robur, Ulmus pumila, гибриды вязов, Ulmus minor, Robinia pseudoacacia, Fraxinus lanceolata, Caragana arborescens, Ribes aureum, Tamarix ramosissima) were studied, their salt resistance and durability of the seed generation were studied. Based on the results obtained it was concluded that the most promising for protective afforestation are such genera as: Ulmus pumila, Ulmus pumila x carpinifolia, Ulmus carpinifolia, Robinia pseudoacacia, Celtis occidentalis и Caragana arborescens, the breeding efficiency of which has been proved by the general condition of many protective forest plantations and their resistance in the arid region.

干旱区绿洲城市树木健康评估及影响因素——以乌鲁木齐市为例

PDF HTML阅读 XML下载 导出引用 引用提醒 干旱区绿洲城市树木健康评估及影响因素——以乌鲁木齐市为例 DOI: 10.5846/stxb202106111558 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目（31770750，31971713） Health assessment of urban trees in arid land oasis cities and its influencing factors: a case study of Urumqi Author: Affiliation: Fund Project: The National Natural Science Foundation of China (31770750，31971713) 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:树木作为城市绿色基础设施重要组分，其健康直接影响城市生态系统服务及人居环境质量。城市化进程加快导致生态土地缺失，同时缺乏合理养护加之极端自然条件干扰对树木健康造成严重威胁。为揭示城市树木健康风险及影响因素，对乌鲁木齐市核心城区117个样地绿化树木进行健康评估，从4个维度12个指标构建树木健康分级体系，基于样地调查结果，分析树木组成、结构、关联性、健康状况及影响因素，揭示乌鲁木齐市不同功能区树木健康差异。旨在为研究区树木健康保护、城市绿地可持续经营及城市生态文明建设提供理论依据和数据支撑。结果表明：（1）乌鲁木齐市城市园林树木乔灌比为8.3 ： 1，树木多样性与种间关联程度较低。榆树占比高达43.87%，其中白榆占比22.62%，是主要优势树种；（2）不同树种健康程度呈现差异性，榆树类健康状况呈现圆冠榆 > 大叶榆 > 白榆 > 垂枝榆特征；（3）城市不同功能区树木健康也呈现异质性；以公园和居住小区树木健康分值较高，而行道树和学校庭院树木健康分值相对较低，且冗余分析进一步揭示地面铺装、林木配置结构、生长空间和胸径对树木健康影响程度最为显著。未来优化城市树木生境条件、提升物种丰富度、加强古树名木保育和提高园林绿化管理水平是维护和提升绿洲城市树木健康的重要举措。 Abstract:Urban green space is an important natural and heterogeneous component of urban landscape, which plays an important role in providing urban ecosystem services and improving residents' well-being. As an important component of urban green infrastructure, the health status of urban trees directly affects urban ecosystem services and the quality of human settlement environments. The accelerated urbanization process leads to the loss of ecological land, and the lack of reasonable maintenance and the disturbance of extreme natural conditions pose a serious threat to the health of urban trees, affecting the effective development of the ecological, social and economic benefits of trees. In order to find the risk and influencing factors of urban tree health, a tree health index system was constructed from 4 dimensions and 12 indexes. Based on the survey of 117 sample plots in core urban area of Urumqi, through analyzing the tree composition, structure, association, health status and its influencing factors, the differences of tree health are revealed in different functional zones. The purpose is to provide theoretical basis and data support for tree health protection and sustainable management of urban green space in the study area, which is of great significance to play the landscape service function of green space and improve the degree of urban ecological civilization. The results show that:(1) the average ratio of trees to shrubs in core urban areas in Urumqi is 8.3:1; especially, the tree species diversity, inter and intra correlation of urban green species are low. Elm (Ulmus spp.) accounts for 43.87% of the total urban trees, of which Ulmus pumila accounts for 22.62%, which is the main dominant tree species. (2) There are some differences of the health status between different Elm species. The overall health status of the Elm species elaborates the characteristics of Ulmus densa > Ulmus laevis > Ulmus pumila > Ulmus pumila cv. pendula. (3) The tree health presents heterogeneity in different urban functional zones, which main public parks and residential areas are higher, while roadside and schools are relatively lower. The redundancy analysis further reveals that ground pavement, tree configuration structure, growth space and diameter at breast height (DBH) have the greatest contribution on the tree health. In the future, optimizing urban tree habitat conditions, improving species richness, strengthening conservation of ancient trees and improving landscape planning and management level are important measures to maintain and improve the health status of urban trees in arid land oasis cities. 参考文献 相似文献 引证文献

Агроэкологическая оценка почв под лесными насаждениями защитной зоны города Астаны

Purpose of research – determine the influence of the degree of soil salinity on the state of hardwood plantations in the green zone of Nur-Sultan city The objects of research were forest plantations growing on soils with limited forest suitability. Artificial plantations of silver birch Betula pendula and Siberian elm Ulmus pumila in 2006 and 2010 of the same age class were selected for the study. Depending on the state of artificial plantations, soil tilling was carried out on the test plots at the depth of the root formation and soil samples were used for the analysis. It was revealed that there is diversity in the type of soil salinity across all sample plots and the most common one is chloride and sulfate salinity that is found in both healthy and weakened stands of both tree species. In chloride and sulfur chloride soil salinization, the physical state of birch plantations was signifi cantly reduced. The content of the sum of toxic salts in the soil under forest plantations of the Siberian elm in healthy stands was minimal, which was gradually increasing with the deterioration of the condition of the trees. In silver birch species, approximately the same content of the total salts was observed in healthy and deteriorated plantations, the increase in toxic salts contents was observed in weakened plantations. The height and diameter of trees in healthy stands of both tree species exceeded those of trees in weakened plantations, judging by the coefficient of variation, tree growth was heterogeneous. It was determined that for the Siberian elm the amount of salts of 0.057% is lethal, the salt content in the amount of 0.014% does not affect the decline in the condition and growth of trees. For the forest plantations of silver birch, contradictory results have been obtained, which require additional research.

Comparison of climate diagrams and their modifications when interpreting botanical studies

The article deals with present approaches to evaluating climate diagrams of Walter-Gossen and Ball-Taylor. Climate diagrams of Ball-Taylor were modified with new methodical elements (base growth temperature line and index of aridity) showing the peculiarities of territories and the ecology of species. Analysis of the growth activity of annual shoots of J. oblonga plants and morphological and anatomical characteristics of the leaves of Platanus orientalis L., Quercus robur L., Ulmus pumila L. in Makhachkala with the use of modified climate diagrams of Ball-Taylor has allowed to get a complete picture of the adaptive mechanisms of plants of these types to weather conditions.

Invasion of Siberian Elm (Ulmus pumila) Along the South Platte River: the Roles of Seed Source, Human Influence, and River Geomorphology

Invasion of Siberian Elm (Ulmus pumila) Along the South Platte River: the Roles of Seed Source, Human Influence, and River Geomorphology

Effects of Red Mud on Plant Growth in an Artificial Soil Mixture

Transforming economies towards the increased circular use of raw materials and keeping resource consumption within planetary boundaries is a major challenge. In our previous research, we utilized sewage sludge to produce artificial soil mixtures well-suited to the biological recultivation of degraded areas. The present study investigated how we can integrate red mud, often considered waste, into this circular management form. With red mud volume ratios of 15% and 30%, we experienced good germination and growth in Siberian elm (Ulmus pumila L.), white poplar (Populus alba L.), black locust (Robinia pseudoacacia L.) and the perennial multipurpose crop, Virginia mallow (Sida hermaphrodita L.). Our results indicate that it is worthwhile to scale up this cheap, economically and ecologically favourable combined waste recovery and mine reclamation technology and to expand its use to fullscale operation.