Influence of Topography on the Distribution and Structure of Woody Plants in the Senegalese Sahel (Sandy Ferlo)

This study describes the floristic composition and structure of a woody stand in the Senegalese Sahel, paying particular attention to the edaphic factors of its floristic composition. A stratified inventory considering the different relief units was adopted. Woody vegetation was surveyed using a dendrometric approach. The results obtained show that the flora is dominated by a few species adapted to drought, such as Balanites aegyptiaca (L.) Del., Calotropis procera Ait. and Boscia senegalensis (Pers.). The distribution of this flora and the structure of the ligneous plants are linked to the topography. In the lowlands, the flora is more diversified and the ligneous plants reach their optimum level of development compared with the higher relief areas. In the lowlands, there are a few woody species which, in the past, were indicative of better climatic conditions. These are Anogeissus leiocarpus (DC.), Commiphora africana (A. Rich.), Feretia apodanthera Del., Loeseneriella africana (A. Smith), Mitragyna inermis (Willd.) and Sclerocarya birrea (A. Rich). It is important that their reintroduction into reforestation projects takes account of their edaphic preference.

Unveiling the adaptation strategies of woody plants in remnant forest patches to spatiotemporal urban expansion through leaf trait networks

Background:With the expansion of urban areas,the remnants of forested areas play a crucial role in preserving biodiversity in urban environments.This study aimed to explore the impact of spatiotemporal urban expansion on the networks of leaf traits in woody plants within remnant forest patches,thereby enhancing our understanding of plant adaptive strategies and contributing to the conservation of urban biodiversity.Methods:Our study examined woody plants within 120 sample plots across 15 remnant forest patches in Guiyang,China.We constructed leaf trait networks (LTNs) based on 26 anatomical,structural,and compositional leaf traits and assessed the effects of the spatiotemporal dynamics of urban expansion on these LTNs.Results and conclusions:Our results indicate that shrubs within these patches have greater average path lengths and diameters than trees.With increasing urban expansion intensity,we observed a rise in the edge density of the LTN-shrubs.Additionally,modularity within the networks of shrubs decreased as road density and urban expansion intensity increased,and increases in the average path length and average clustering coefficient for shrubs were observed with a rise in the composite terrain complexity index.Notably,patches subjected to‘leapfrog’expansion exhibited greater average patch length and diameter than those experiencing edge growth.Stomatal traits were found to have high degree centrality within these networks,signifying their substantial contribution to multiple functions.In urban remnant forests,shrubs bolster their resilience to variable environmental pressures by augmenting the complexity of their leaf trait networks.

Native Species Composition and Diversity of Valuable Woody Plants Regeneration during Fallow Period in Kamwatta, Moruca, Guyana

An intelligent method of shifting cultivation to regenerate vegetation after a long fallow period is critical information for restoration strategies. The literature review identified that the assessment of woody plant species on abandoned farmland has never been done before in Kamwatta, Moruca Region 1. In addition, more information should be available in indigenous communities and at the national level, including more documentation of the utilization of natural resources by the Warrau community. This study assessed the valuable woody plant species that grew during the fallow periods. Nine farmlands were randomly selected along a 100 m transect, each with varying fallow periods. In order to collect information on the age of farm abandonment, the researcher employed a mixed-methods approach. First, we found how long each farm had been fallow by administering a semi-structured questionnaire. Then, we conducted a flora survey to gain information on the variety and abundance of valuable plants using the age of farm abandonment as a dependent variable. The data analysis included the number of valuable woody trees with a diameter of >10 cm, seedlings and saplings with a diameter of <10 cm, the location of identified trees, and the uses of identified tree species. Microsoft Excel was used to code and analyze the questionnaire, while QGIS, Shannon’s Index of Diversity, and Simple Linear Regression were used to analyze the inventory data. The results showed that the respondents listed 38 valuable woody species, and 79% occurred in the studied area. The field verification revealed that the dominant family in the area was Mimosaceae. Species abundance increased with fallow up to 10 years before declining in the latter years. Plant diversity and abundance had a weak relationship with the age of abandoned farmlands for woody trees, while the seedlings and saplings showed no relationship.

Distribution changes of woody plants in Western Iran as monitored by remote sensing and geographical information system:a case study of Zagros forest

The status of woody plants in dry-land systems is a fundamental determinant of key ecosystem processes. Monitoring of this status plays an important role in understanding the dynamics of woody plants in arid and semi-arid ecosystems. The present study determined the dynamism of the Zagros forests in Iran using Remote Sensing and Geographic Information System techniques and statistical science. The results show that the density of trees varied from 10 to 53 % according to the physio- graphic and climatic conditions of semi-arid regions. The best and lowest correlation between vegetation indices and forest density were obtained for the global environmental monitoring index （GEMI; R2 = 0.94） and soil adjust vegetation index （R2 = 0.81）, respectively. GEMI is used to monitor land use changes over a 10-year period. Results show that 2720 ha2 of forest have been destroyed by human interference and tillage on steep slopes during this period which also resulted in the loss of the fertile soil layer. GEMI determined the areas with a biomass of trees and could normally separate border regions with low bio- mass density of trees from regions without canopy cover. The results revealed that assessment of forest and vegetation cover in arid and semi-arid arduous forest regions using satellite digital numbers and ordinary sampling is subject to uncertainty. A stratified grouping procedure should be established to increase the accuracy of assessment.

Structural traits of woody plants and geomorphological conditions to the vegetation recovery at Ksudach caldera(Southern Kamchatka) since the explosive eruption in 1907

This study considers the restoration of the plant cover destroyed by a catastrophic volcano eruption in the south of Kamchatka Peninsula(the Ksudach caldera,Shtyubel cone),with a particular attention to the role of woody plants.It aims to qualitatively estimate(at a qualitative level)the rate of the primary succession development depending on the microrelief and the modern relief-forming processes.The vegetation recovery in the caldera after the Shtyubel cone eruption 109 years ago proceeds slowly and irregularly.It proceeds most slowly on a thick tephra mantle continuously disturbed by water and wind erosion,lahars,debris flows,landslides,etc.Such conditions are most typical of the western part of the caldera dominated by pumice fields with occasional patches of pioneer herbs and dwarf shrubs.Alpine tundra communities with gradually expanding patches of shrub alder develop in the southern,eastern and northeastern parts of the Ksudach caldera.Since 1997 the area of the shrub alder communities has increased by 1.9 times,while the alpine tundra–by 1.3 times only.The woody plants(dwarf shrubs and prostrate shrubs)are of particular importance in the process of the vegetation recovery on pumice fields.We suggest that the bark thickness of woody plants is an integrated indicator,which may serve for estimating the state of ecosystem in the course of the primary succession development on juvenile sediments.The extremely inhospitable environments cause changes in physiological processes in the plant body and in its bark in particular.The results show that woody plants have a"thin"bark and develop some structural-functional arrangements for keeping bark tissues at their minimum.So,the woody plant structure and the rate of changes in plant communities are under control of the geomorphic conditions and primarily–of physicochemical features of the pyroclastic cover.

The 2/3 scaling of twig nitrogen to phosphorus in woody plants

Background:Nitrogen(N)and phosphorus(P)are important elements for plant metabolism and growth.Therefore,the quantification of the scaling relationship of N to P in plant organs can help us understand many fundamental ecological processes.The general scaling relationships between N and P in leaves and in fine roots have been reported.As compared to leaves and fine roots,however,little information is available on the N versus P scaling relationship in the stems of woody plants,especially for twigs.In this study,a comprehensive dataset comprising 2,038 N=P paired observations for a total of 536 woody species was compiled and analyzed to determine whether a general scaling relationship exists.Results:The global mean values of twig N and P concentrations and N:P ratios were 9.33 mg⋅g^(-1),1.12 mg⋅g^(-1) and 10.16,respectively.Twig N and P concentrations and N:P ratios differed significantly within and across functional groups and biomes.Across all of the species,a uniform 0.67 scaling exponent of twig N to P was observed across different functional groups and biomes,i.e.,a 2/3-power scaling relationship was observed.However,this numerical value differed across different sites,albeit converging onto 0.67 with increasing sample sizes.Soil total phosphorus was the largest contributor to the variation in the numerical value of the scaling exponent.Conclusion:These results provide useful parameters for stoichiometric growth models,and advance our understanding of the mechanisms underlying plant nutrient dynamics.This study has potential implications in predicting responses of nutrient cycling in terrestrial ecosystem responses to changes in the environment.

Analysis of the State of Woody Plants in the City of Nukus (Streets of Ernazar Alakoz)

This article observed seven species of Fraxinus excelsior L., Fraxinus pensylvanica March., Salix alba L., Populus alba L., Juniperus communis L., Catalpa bignonioides Walt., Ulmus densa Litv for seasonal growth. The Republic of Karakalpakstan is located in the North-West of Uzbekistan, covers 166,600 km2 (28%), and is the largest in terms of territory by region. The study of woody plants in the flora of Karakalpakstan is an important aspect of the convention on biological diversity. The species composition of the natural flora of Karakalpakstan is quite poor in ornamental plants, especially evergreens, suitable for gardening. At the same time, the biodiversity of these plants in Nukus and the factors contributing to them were analyzed. Relevance of the study: Creating an environmentally friendly environment in cities is possible by optimizing intra-urban tree plantations that perform forming, improving and regulating functions in the environment. The effectiveness of green spaces mainly depends on the range of trees and shrubs and their correct use in accordance with biological characteristics, environmental requirements and decorative qualities. The degree of impact of plantings on the environment also depends on the type, age and physiological characteristics of plants [1]. Woody plants, unlike hardwoods, enrich and purify the air throughout the year and can be used for single and group planting when creating hedges and borders, as well as green gardens. All year round, they enrich the air with oxygen, absorb street noises, and lower the air temperature. However, the conservation of flora is necessary not only for individual components, but also for the entire population diversity. Salinized land, unfavorable climate and other environmental factors are among the obstacles or restrictions to the introduction of new species of trees and shrubs, especially evergreen ones, in arid areas [2] [3]. The urban environment differs from the natural environment in terms of the degree of illumination, the amount of solar radiation, air temperature and humidity, soil properties, etc. In this regard, green plants only with proper planning, selection of assortment, sufficient quantity and good care ensure the improvement of the ecological state of the city. For scientifically based gardening, it is necessary to have objective ideas not only about the quantity and quality of existing plantings, but also to know the ecological and physiological state of each species, which allows us to assess the role of plants in improving the quality of the environment [4]. The sharply continental climate, aridity of the territory, increased wind activity and salinity of the soil contribute to the aggravation of environmental problems in the cities of the southern Aral sea region. The deteriorating environmental situation in Nukus requires the development of a specific gardening strategy aimed at creating sustainable urban plantings of various types. In this regard, we conduct research on the biological characteristics of ornamental woody plants in urban conditions. The range of tree and shrub species used in the landscaping of the city of Nukus remains quite poor today [5]. The predominant tree species are P. alba L., P. nigra L., P. diversifolia L., F. excelsior L., F. pensylvanica Marsh., Fraxinus potamaphylla Herd, S. excels S. Gmel, S. babylonica L., S. alba L., Juniperus communis L. In the landscaping of Nukus, introduced plants are also used, which have adapted to local conditions, although they are damaged by frosts. These include C. bignonioides Walt, Ulmus pumila L., F. pensylvanica Marsh.

Genetic control of flowering time in woody plants： Roses as an emerging model

Genetic control of the timing of flowering in woody plants is complex and has yet to be adequately investigated due to their long life-cycle and difficulties in genetic modification.Studies in Populus,one of the best woody plant models,have revealed a highly conserved genetic network for flowering timing in annuals.However,traits like continuous flowering cannot be addressed with Populus.Roses and strawberries have relatively small,diploid genomes and feature enormous natural variation.With the development of new genetic populations and genomic tools,roses and strawberries have become good models for studying the molecular mechanisms underpinning the regulation of flowering in woody plants.Here,we review findings on the molecular and genetic factors controlling continuous flowering in roses and woodland strawberries.Natural variation at TFL1 orthologous genes in both roses and strawberries seems be the key plausible factor that regulates continuous flowering.However,recent efforts suggest that a two-recessive-loci model may explain the controlling of continuous flowering in roses.We propose that epigenetic factors,including non-coding RNAs or chromatin-related factors,might also play a role.Insights into the genetic control of flowering time variation in roses should benefit the development of new germplasm for woody crops and shed light on the molecular genetic bases for the production and maintenance of plant biodiversity.

Relative sensitivities of woody plants to acid deposition in south areas of China

Relative sensitivities of 30 species of common woody plants to simulated acid rain with pH values of 2.0, 2.5, 3.0, 3.5, 4.5 and control were studied. The results showed that 6 species of these plants were sensitive to simulated acid rain. The moderate included 18 species. The resistant included 6. Relative sensitivities to ambient acid rain and air pollutants and visible injury degree of 30 species of common woody plants in Chongqing City were investigated. Results showed that 6 species with foliage lesion rate at above 10 percent were sensitive, that 6 species with no lesion were resistant and that other 18 species with lesion at 10 percent below were moderate. Other 7 cities (Guiyang, Zunyi, Duyun, Changsha, Zhuzhou, Liuzhou and Guilin City) were also investigated and results were consistent with those of Chongqing City. The experimental and investigated results showed relative sensitivities and visible injury degree of woody plants to simulated acid rain were consistent with those of the woody plants to ambient acid rain and air pollutants. The sensitive plants may be used as bioindicators to acid rain or air pollutants. The resistant species can be introduced to acid rain and air pollution areas to substitute damaged sensitive plants in order to improve environment.

The Comparison of Cold tolerance of Three Species of Evergreen Broad-leaved Woody Plants

[Objectives]This study aimed to select evergreen broad-leaved woody plants with higher ornamental value and stronger cold tolerance for introduction from the south to the north,and to apply them to urban greening,so as to enrich the plant community structure of the landscape in the northern region.[Methods]Three species of evergreen broad-leaved woody plants,i.e.,Ligustrum lucidum,Ilex cornuta and Eriobotrya japonica,were selected as the experimental materials.The morphological performances and the changes of the physiological indexes were observed and measured during the overwintering period in the open field in Beijing.The relationship between the indexes and the low temperature was also analyzed.The strength of cold tolerance of the three species was compared.[Results]The electrical conductivity,the contents of MDA and proline were negatively correlated with the corresponding low temperature.The contents of soluble sugar and soluble protein increased with the dropping temperature,but they had little response to the short-term temperature rise.[Conclusions]Combined with morphological and physiological indexes,it was found that the changes of the contents of proline and soluble sugar among the physiological indexes were closely related to the cold tolerances of the three tree species of broad-leaved woody plants.The cold tolerance of I.cornuta was the strongest,E.japonica was the second,and that of L.lucidum was the worst.

A new low-cost sensing system for rapid ring estimation of woody plants to support tree management

Continuous monitoring of the diameter and rings of woody plants is required to evaluate agroforestry products such as timber.Manual measurement is still widely used to monitor tree growth but it is time-consuming.In addition,advanced equipment and software are available but they require technical skills and are costly for smallholders.However,we have developed a rapid and low-cost sensing system for estimating the diameters of woody plants.The apparatus includes a sensor and Internet of things(IoT)technology,which can be used under any network conditions.The apparatus was tested with various trees and the results were compared with those obtained by manual measurement.The findings using the newly developed system demonstrate a strong correlation(R2=0.99)with the manually performed measurements.This rapid and low-cost diameter sensing system will be useful in the expansion of agroforestry sensing networks and beneficial to smallholders.Hence,the system will assist in informing foresters of potential problems in timely manner.

Species composition and influencing factors of understory woody species in Robinia pseudoacacia plantations on the Loess Plateau

Black locust(Robinia pseudoacacia L.)plantations have contributed significantly to soil and water conservation and ecological reconstruction on China’s Loess Plateau.Understanding the impact of stand and environment on species composition of understory woody plants will improve the stability of existing black locust plantations.Ten stands were selected in second-generation black locust plantations in tableland and gully areas of the Loess Plateau.The number of understory tree species in the tablelands was significantly lower than in the gully stands.Regenerated black locust(19.76%)and Rubus corchorifolius L.f.(64.85%)were the most abundant understory tree and shrub species,respectively,in the tableland stands;Broussonetia papyrifera(L.)L’Hér.ex Vent.(6.77%)and Acanthopanax senticosus(Rupr.Maxim.)Harms.(37.22%)were most abundant in the gully stands.Species richness(S),Shannon diversity(H),and evenness index(J)of the understory plants were significantly lower in the tableland stands than in the gully stands.More diverse understory species and community structures occurred in the gully stands.Differences in species diversity among landform positions may be attributed to differences in soil moisture.In addition,77.57%of the variation in understory species composition was explained,among which shrub and herb coverage,stand age,leaf area index,slope and total soil phosphorus in the 10-20 cm layer were the main factors.Soil organic carbon and total potassium significantly impacted S,H and J.Considering the environmental conditions and the biological characteristics of the plants investigated,R.corchorifolius should be given priority in the development of tableland stands,while B.papyrifera and Celtis sinensis Pers.should form mixed forests with black locust in gully stands.This management could promote biodiversity and stability of the existing black locust plantations but also optimize regional landscape patterns.

Scope of biodiesel from oils of woody plants:a review

Non-edible oils obtained from chosen non-conventional woody plants are considered as potential raw materials for biodiesel production.These plants mostly grow in wastelands.Structural characteristics of these oils as raw material are very much in tune with the properties of biodiesel such as long-chain hydrocarbon,having an adequate level of unsaturation with branched chain.Four primary methods are being followed to make biodiesel from vegetable oil.They are direct use through blending,microemulsion,thermal cracking(pyrolysis)and transesterification.Non-edible oil would eliminate the issue of food vs fuel.The biodiesel manufactured from oils of woody plants may partially reduce the demand for liquid-fuel energy and addresses the environmental consequences of using fossil fuels.Oil from a total of 17 species of woody plants(Angiosperms)belonging to 14 families are considered in this paper.The habit,habitat and geographical distribution of each species are also presented.The physico-chemical properties of their oil,with special reference to the fatty-acid profile that ultimately decides the characteristics of the biodiesel prepared from them,are reviewed.

Woody Climbing Plants and Their Landscaping Application in Chongqing City

There are a variety of woody climbing plants distributed widely in Chongqing City, and they are loved by landscape designers due to their special form and saving space. In respect of actual application,there is a big difference between various species of woody climbing plants in terms of proportion. In this paper, woody climbing plants in Chongqing City were investigated. The results show that there are74 species of woody climbing plants suitable for landscape in Chongqing City. The research can provide reference for the application of woody climbing plants in landscape greening in Chongqing City in future.

Research on the Evaluation System of Woody Landscape Plants Maintenance

The maintenance management of urban landscape plants play an important role in bringing their landscape and ecological functions into full play. In this paper,analytic hierarchy process（ AHP） was used to select 13 specific indicators to construct the evaluation system of woody landscape plant maintenance effectiveness from 3 aspects of ornamental,growth status and soil condition combined with qualitative and quantitative analysis,with the aim to explore an effective and scientific method to evaluate the effectiveness of landscape plant maintenance.

Metabolic engineering in woody plants: challenges, advances, and opportunities

Woody plant species represent an invaluable reserve of biochemical diversity to which metabolic engineering can be applied to satisfy the need for commodity and specialty chemicals,pharmaceuticals,and renewable energy.Woody plants are particularly promising for this application due to their low input needs,high biomass,and immeasurable ecosystem services.However,existing challenges have hindered their widespread adoption in metabolic engi neering efforts,such as long generation times,large and highly heterozygous genomes,and difficulties in transfor mation and regeneration.Recent advances in omics approaches,systems biology modeling and plant transformation and regeneration methods provide effective approaches in overcoming these outstanding challenges.Promises brought by developments in this space are steadily opening the door to widespread metabolic engineering of woody pl ants to meet the global need for a wide range of sustainably sourced chemicals and materials.

Introduction of Woody Landscape Plants in Linzhi City of Tibet

Due to the special geographical conditions of Tibet,the plant species applied in local landscaping have been limited.In the landscaping project of Fujian Park,59 woody landscape plant species were introduced from the hinterland,and the survival rate and growth vigor of these species had been observed for 15 years.In terms of growth vigor and ornamental character,about 32 species showed good performance such as Prunus cerasifera f.atropuipurea and Dendrobenthemia japonica;8 species showed moderate growth performance such as Metasequoia glyptostroboides Hu et Cheng and Magnolia denudata Desr.;14 species showed poor growth vigor such as Ginkgo biloba L.and Osmanthus fragrans Lour.,and 5 species died such as Albizzia julibnssin Durazz.and Hibiscus mutabihs L..Moreover,the paper explored key factors that influence the introduction of woody landscape plants in Linzhi City and pointed out that wind damage and low temperature were 2 key factors.

Variability in Wood Density and Wood Fibre Characterization of Woody Species and Their Possible Utility in Northeastern Mexico

Context: Preliminary screening has been undertaken by woody species of Tamaulipan thornscrub for wood density and its utilization northeastern Mexico for different purposes and to find possible relationship of density with wood fibre characteristics. This technique can be used in the selection of species with high wood density for possible utility. Aims: It is to determine the variability in wood density and in fiber cell morphology and its length and among wood species of the Tamaulipan thornscrub, northeastern Mexico. Methods: Wood density and wood fibres are characterized in these woody species following standard methodology. Results: The results reveal large variability in wood density and in fibre cell morphology h. The species have been classified on the basis of wood density and its fibber cell morphology and has been recommended for their possible utilization for different purposes. Conclusions: Species desirable for strong furniture making, paper pulp, soft furniture, fence etc. can be selected on the basis of fibre length to breadth ratios as strong fibres for furniture and fibre cells with broad lumen and thin cell wall use for fabrication of paper pulp and other utilities.

Investigation of Cultivated Woody Plant Resources in Ping’an District of Qinghai Province in China

[Objectives]To investigate and find the characteristics and distribution of woody plant resources in Ping'an District of Qinghai Province.[Methods]The investigation was carried out by interview method,literature method and route method.[Results]There were 22 families,40 genera and 84 species of woody plants in Ping'an District of Qinghai Province,and their life forms were mainly shrubs.Cultivated woody plants in the study area were dominated by trees;the distribution of families and genera were mainly concentrated in single families,few families,single genera and few genera,the families and genera were narrow;economic value was mainly manifested in ornamental value.[Conclusions]The investigation results are expected to provide a certain reference for the economic development of cultivated woody plants in the study area.

PHYSIOLOGY OF WOODY PLANT UNDER SALT CONDITION

Some advances in researches on the physiology of woody plants under salt condition are reviewed. The salt tolerant woody plants can be divided into two main groups. glycophytes and halophyes. They have different mechanisms for maintaining normal metabolism under salt condition. Halophytes usually are salt accumulators and glycophytes are salt excludors. However,the criteria for salt exclusion is not always coear. Although salt responses of different types of woody plants ard not the same some major changes are identilied identilied in net photosynthesis rate and in growth.Four mechamsms are proved to be related to the salt resitance of woody plants(1) Regulation of ion intake;(2) avoidance of toxicity; (3) maintaining meinbrane mtegrity and (4) ion compartmentation. Currently,conventional plant breeding and bioteclogy are both used to improve salt tolerance of woody plant.