Projecting the potential distribution and analyzing the bioclimatic factors of four Rhododendron subsect. Tsutsusi species under climate warmingOA

Tsutsusi is one of the eight subgenera of the Rhododendron genus.Four Tsutsusi species,R.indicum,R.simisii,R.oldhamii,and R.schlippenbachii,have high ornamental and medicinal values,resulting in an increasing market demand.These species thrive in cool and humid environments and are widely distributed in Europe and Asia.Whether global climate warming will affect the distribution of these valuable resources remains unclear.Thus,this study analyzed the climatic suitability of these species for the ...     

Relationship between species diversity and tree size in natural forests around the Tropic of CancerOA

Although numerous hypotheses have been proposed to explain the patterns of species diversity of forests at local and landscape levels,it is still difficult to predict the alpha diversity of species,especially in tropical and subtropical natural forests where trees of different sizes and shapes are highly mixed.Size might characterize species diversity,and the possible correlation between these variables may contribute to the development of easy-to-use growth indicators to predict diversity and t...     

Leaf recognition using BP-RBF hybrid neural networkOA

Plant recognition has great potential in forestry research and management.A new method combined back propagation neural network and radial basis function neural network to identify tree species using a few features and samples.The process was carried out in three steps:image pretreatment,feature extraction,and leaf recognition.In the image pretreatment processing,an image segmentation method based on hue,saturation and value color space and connected component labeling was presented,which can ob...     

Contribution of biophysical and climate variables to the spatial distribution of wildfires in IranOA

This study investigated the relationship between climate and biophysical variables in burned areas in Iran.The fire burned area(FBA) product(Fire CCI 5.1.1),land surface temperature(MOD11C3C),vegetation index(MOD13A1),and climate variables such as temperature,wind speed,relative humidity,and volumetric soil moisture from the ERA5 reanalysis dataset were used.Pearson correlation coefficient was used to determine the relationship between biophysical and climate variables and fire occurrence.The re...     

Improved guidelines for any-aged forestryOA

Any-aged forest management(AAF) is a means to reduce clear-felling without compromising profitability or timber production.The concept of AAF is to choose between clear-felling or thinning one harvest at a time based on what is better at that time in terms of the management objectives for the forest.No permanent choice is made between rotation forest management(RFM) and continuous cover forestry(CCF).Optimized AAF is never less profitable than RFM or CCF because all cutting types of both RMF and...     

Dynamic response to climate change in the radial growth of Picea schrenkiana in western Tien Shan,ChinaOA

Forests are important ecosystems for economic and social development. However, the response of tree radial growth to climate has produced ‘divergent problems’ at high latitudes under global warming. In this study, the response stability and trend of Picea schrenkiana radial growth to variability in climate factors were analyzed in the mid-latitudes of the western Tien Shan Mountains. Radial growth of P.schrenkiana was mainly limited by minimum and mean temperatures. The divergent responses of ra...     

Pine wilt disease detection in high-resolution UAV images using object-oriented classificationOA

Pine wilt disease(PWD) is currently one of the main causes of large-scale forest destruction. To control the spread of PWD, it is essential to detect affected pine trees quickly. This study investigated the feasibility of using the object-oriented multi-scale segmentation algorithm to identify trees discolored by PWD. We used an unmanned aerial vehicle(UAV) platform equipped with an RGB digital camera to obtain high spatial resolution images, and multiscale segmentation was applied to delineate ...     

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

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 mongo...     

Responses of terrestrial bryophytes to simulated climate change in a secondary evergreen broad-leaved forest in southern ChinaOA

Tropical regions are biodiversity hotspots and are well-suited to explore the potential influence of global climate change on forest ecosystems.Bryophytes have essential ecological functions in tropical forest ecosystems,but knowledge of the potential impact of global warming and possible changes in water availability patterns on terrestrial bryophytes is limited.We transplanted eight terrestrial moss species from two elevations(900 and 500 m) to warmer and drier elevations(500 and 100 m) during...     

Comparative analysis of thinning techniques in pine forestsOA

Thinning is a necessary and complex forestry activity. The complexity increases due to theoretical disagreements, contradictory recommendations, and errors of modern practice, which require confirmation through longtime experiments. This article presents a summary of experimental results from plantations established 20–30 years ago and explains concepts of the theory, methods, and regime of thinning in permanent sample plots of pine stands in Gatchinsky forest of the Leningrad region. The resear...     

Predicting the upper stem diameters and volume of a tropical dominant tree speciesOA

Predicting upper stem diameters and individual tree volumes is important for product quantification and can provide important information for the sustainable management of forests of important commercial tree species( Shorea robusta) in Nepal. The aim of this study was to develop a taper equation for S. robusta. Fifty-four trees were selected and felled in the southern low land of Nepal. A mixed effect modelling approach was used to evaluate 17 different taper functions. ‘Leave-one-out cross-val...     

Development,differentiation,and material distribution of secondary phloem in Pinus massonianaOA

Phloem is the woody tissue for the storage and long-distance transport of organic matter in vascular bundles.To reveal the process of secondary phloem development and differentiation in Pinus massoniana,the structure of the secondary phloem and the distribution of cell inclusions were observed by histochemical staining,spontaneous fluorescence of phenolic substances and cell segregation.Based on tissue development and differentiation characteristics of P.massoniana secondary phloem,the secondary...     

Responses of arid plant species diversity and composition to environmental factorsOA

An oasis is a unique natural landscape in arid and semi-arid areas,significant for regulating regional microclimates and hydrological processes in deserts.However,little is known regarding the response of natural oasis plants communities to various environmental factors.Nineteen sample plots(50 m×50 m) were selected in the Daliyabuyi Oasis in the Taklimakan Desert hinterland based on the location of groundwater monitoring wells and 76 vegetation quadrats(25 m × 25 m) were established.A two-way i...     

Multi-temporal NDVI analysis using UAV images of tree crowns in a northern Mexican pine-oak forestOA

The use of unmanned aerial vehicles(UAV) for forest monitoring has grown significantly in recent years,providing information with high spatial resolution and temporal versatility.UAV with multispectral sensors allow the use of indexes such as the normalized difference vegetation index(NDVI),which determines the vigor,physiological stress and photo synthetic activity of vegetation.This study aimed to analyze the spectral responses and variations of NDVI in tree crowns,as well as their correlation...     

Assessing fire severity in Turkey's forest ecosystems using spectral indices from satellite imagesOA

Fire severity classifications determine fire damage and regeneration potential in post-fire areas for effective implementation of restoration applications.Since fire damage varies according to vegetation and fire characteristics,regional assessment of fire severity is crucial.The objectives of this study were:(1) to test the performance of different satellite imagery and spectral indices,and two field—measured severity indices,CBI(Composite Burn Index) and GeoCBI(Geometrically structured Composi...     

Bark content variations and the production of Populus deltoides as a source of bioenergy under temperate climate conditionsOA

Bark biomass as an energy source has a high economic value. Bark content variations and production helps recognize the potential of this bioenergy source spatially before harvesting. The percentage of fresh and dry bark in Populus deltoides grown under a monoculture system was examined in the temperate region of northern Iran. Diameter at breast height(DBH) and total height data were analyzed based on an initial inventory. Ten sample trees were felled, separated into 2 m-segments, and weighted i...     

Spatially differentiated changes in regional climate and underlying drivers in southwestern ChinaOA

The climate in Southwest China are predominantly under the influences of three contrasting climate systems,namely the East Asian monsoon,the South Asian monsoon,and the westerlies.However,it is unclear if the diversified climate systems,in combination with the complex terrain and varying vegetation types,would result in contrasting patterns of changes in climate across the region.Based on the CRU TS data for the period 1901-2017,we examined the spatiotemporal characteristics of the regional clim...     

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

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 tabl...     

Soil organic carbon storage in forest restoration models and environmental conditionsOA

The scale of forest and landscape restoration is expected to increase during the UN Decade on Ecosystem Restoration and its contribution to the provision of critical ecosystem services to society. Several models of forest restoration may improve ecosystem services, including soil organic carbon(SOC) storage. A review was carried out to access:(1) the variability of SOC storage between worldwide forest restoration models and,(2) the effects of climate, soil class, soil texture, and vegetation typ...     

Spatial pattern analysis of forest trees based on the vectorial markOA

Analysis of spatial patterns to describe the spatial correlation between a tree location and marks(i.e., structural variables), can reveal stand history, population dynamics, competition and symbiosis. However, most studies of spatial patterns have concentrated on tree location and tree sizes rather than on crown asymmetry especially with direct analysis among marks characterizing facilitation and competition among of trees, and thus cannot reveal the cause of the distributions of tree locations...