Key challenges and approaches to addressing barriers in forest carbon offset projectsOA

Forest carbon offset(FCO) projects play an increasingly important role in mitigating climate change through market mechanisms in both compliance and voluntary markets. However, there are challenges and barriers to developing an FCO project, such as carbon leakage and cost-eff ectiveness. There have been few attempts to summarize and synthesize all types and aspects of existing challenges and possible solutions for FCO projects. This paper systematically reviews and discusses the current challeng...     

Soil respiration in a natural forest and a plantation during a dry period in the PhilippinesOA

Climate change is forecast to increase the frequency of extreme hot temperatures and dryer days and is anticipated to have profound impacts on the global carbon budget.Droughts are expected to alter soil respiration(R_s) rates,but the scarcity of data preclude a reliable estimate of this response and its future trajectory.A field experiment using an automated soil respiration machinery(LI-8100A) was conducted in a natural forest and a plantation during a dry period in the Philippines,w...     

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...     

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...     

An attention-based prototypical network for forest fire smoke few-shot detectionOA

Existing almost deep learning methods rely on a large amount of annotated data,so they are inappropriate for forest fire smoke detection with limited data.In this paper,a novel hybrid attention-based few-shot learning method,named Attention-Based Prototypical Network,is proposed for forest fire smoke detection.Specifically,feature extraction network,which consists of convolutional block attention module,could extract high-level and discriminative features and further decrease the false alarm rat...     

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...     

Aspects of forest restoration and hydrology:the hydrological function of litterOA

Although forests play important roles in the hydrological cycle,there is little information that relates the water retention capacity of litter in areas under passive restoration,especially in Cerrado savannas.This study relates litter levels to water holding capacity and effective water retention among forest fragments under different passive restoration stages:46,11,and 8 years to better understand litter hydrological functions in the Cerrado.Water retention c apacity and effective water reten...     

Using mixed integer programming and airborne laser scanning to generate forest management unitsOA

Airborne laser scanning(ALS) has been widely applied to estimate tree and forest attributes, but it can also drive the segmentation of forest areas. Clustering algorithms are the dominant technique in segmentation but spatial optimization using exact methods remains untested. This study presents a novel approach to segmentation based on mixed integer programming to create forest management units(FMUs). This investigation focuses on using raster information derived from ALS surveys. Two mainstrea...     

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...     

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...     

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...     

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...     

Within-and between-population variations in seed and seedling traits of Juglans mandshuricaOA

In order to quantify within-and between-population variation in seed and seedling traits of Juglans mandshurica and reveal the relationship among genetic and environmental variations and select elite families, samples of 50 J. mandshurica families from five natural populations in Liaoning Province, northeast China, were taken to measure seed and seedling traits. The results show that all seed traits varied significantly among families within the population, but only kernel weight and kernel rate...     

Soil phosphorus fractions and their availability over natural succession from clear-cut of a mixed broadleaved and Korean pine forest in northeast ChinaOA

To assess phosphorus(P) status of forest soil under naturally restored vegetation, P fractions in the 10-cm soil layer were quantified at different successional stages on the clear-cut site of mixed broadleaved and Korean pine forest. Four communities of shrub, softwood broad-leaved forest, softwood and hardwood broad-leaved forest, and hardwood broad-leaved forest represented different successional stages. A soil sample from a primary broad-leaved and Korean pine stand was the control. A sequen...     

Throughfall and stemflow chemical dynamics of Satoyama,a traditional secondary forest system under threat in JapanOA

The term ’Satoyama’ refers to traditional and unique secondary forests in Japan that occupy intermediate zones between villages(’sato’) and hills or mountains(’yama’).Satoyama landscapes help sustain ecosystem services and the diversity of secondary natural environments.As Japan relies more heavily on foreign timber imports,the traditional role of Satoyama in providing forest products has diminished,and this has led to their abandonment and poor management.The chemical behavior of cations,anions...     

Carbon stock estimation by dual-polarized synthetic aperture radar(SAR) and forest inventory data in a Mediterranean forest landscapeOA

Forest ecosystems play a crucial role in mitigating global climate change by forming massive carbon sinks.Their carbon stocks and stock changes need to be quantified for carbon budget balancing and international reporting schemes.However,direct sampling and biomass weighing may not always be possible for quantification studies conducted in large forests.In these cases,indirect methods that use forest inventory information combined with remote sensing data can be beneficial.Synthetic aperture rad...     

Experimental approaches to select tree species for forest restoration: effects of light,water availability and interspecific competition in degraded areasOA

Knowing what native trees can recr uit on degraded areas allows selecting the best species to restore these sites. However, as this information is not often available, experimentation is required before large-scale planting. This study used ex situ experiments to make these decisions on recruitment. Competition with r-strategist plants, excessive solar radiation and water shortage commonly impair tree recruitment in open habitats. The experiments focused on the interactions among these factors a...     

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 ...     

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 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...