This study aims to systematically examine the application of Remotely Piloted Aircraft Systems (RPAS) for estimating vegetation height in natural and planted forests, aiming to understand the critical challenges encountered by identifying the methods and technologies employed.
Since 2018, the use of RPAS for vegetation height estimation has grown substantially, spanning diverse applications ranging from direct height measurements to biomass modelling. Researchers widely favour multirotor platforms because of their versatility and affordability. Moreover, LiDAR technology stands out for its high accuracy in estimating vegetation height. Despite their potential, accurate segmentation of individual trees within dense canopies remains a significant challenge, necessitating further research into advanced algorithms and sensor integration. The article further emphasises analytical methodologies– such as segmentation, classification, and machine learning techniques — that enhance tree delineation, species identification, and overall forest structure analysis.
The increasing demand for efficient and cost-effective forest monitoring methods has driven the adoption of RPAS. This systematic review analyses 133 publications (2013–2024) concerning the use of RPAS in estimating vegetation height in natural and planted forests. The findings highlight the prevalence of multirotor platforms, which are valued for their affordability and versatility, and the extensive application of LiDAR sensors, which are renowned for their precision. A growing trend in the combined use of sensors enhances estimation accuracy and broadens potential applications. Despite these advancements, challenges such as segmentation within dense canopies and identifying individual trees persist. Integrating sensors with machine learning algorithms is a promising solution, potentially optimising forest inventories and sustainable management practices. This study also identifies research opportunities in underexplored areas, such as the measurement of seedlings at early growth stages, underscoring the strategic role of RPAS in contemporary forestry.
Tree species mixtures are often more productive than monocultures. One possible reason for this is higher absorption of photosynthetically active radiation (APAR) and improved light use efficiency (LUE) in mixtures. Here, we identified the processes influencing APAR and LUE in forests, examined how APAR and LUE are influenced by mixing species or reducing stand density, how these effects vary along site gradients, and implications for modelling of forest growth.
Eight of 18 cases had 4 to 86% (mean 27%) higher stand APAR in mixtures than the most productive monoculture, four found 13 to 49% (mean 25%) higher APAR compared to the average of the monocultures, and three found lower APAR in mixtures than in the monoculture with lowest-APAR. Following the same sequence of comparisons for LUE in mixtures vs. monocultures, the counts were ten, one and four cases, respectively. Reductions in stand density reduced stand APAR, and either increased or did not influence LUE. While a common set of interactions and structural characteristics influenced APAR and LUE, their importance varied among forest types, sites, and ages, pointing to the value of using models to understand these processes. At nutrient and water rich sites, where leaf areas and competition for light are high, increased APAR in mixtures typically leads to increased productivity.
In mixtures, stand-level APAR and LUE can be greater than in monocultures, but this is not always the case, and the causes vary between forest types and sites. Increases in APAR or LUE do not necessarily increase growth, which is more likely on sites with higher soil resources and favourable climatic conditions. Forest growth models are available that summarise this information in a form that can be used by forest practitioners.
The introduction of cable yarding systems has transformed timber harvesting operations on steep slopes. Subsequent adaptations and modernizations of rigging configurations, carriages, and work practices have led to substantial improvements in safety, productivity, and environmental performance. This review focuses on the base, or carrier, of the cable yarder and identifies recent improvements, thereby offering insight into emerging opportunities for future developments.
Hybridization and electrification of carrier drivetrains, leveraging cable yarding's distinctive suitability for energy recuperation, has been introduced as a measure to enhance fuel economy and reduce CO₂ and noise emissions, thereby improving economic and environmental performance as well as occupational safety. The creation of a more attractive and safer working environment has been achieved through the increased use of excavators as carrier platforms for unguyed yarders, which have been instrumental in extending fully mechanized harvesting to steep slopes. In addition, this type of machine allows economic viability to be maintained in the smaller operations that are expected to be the norm in the future through lower machine costs and faster relocation. New information and communication technologies have made carriers a key source of machine sensor data for production control, monitoring and coordination, predictive maintenance and overall system optimization.
The yarder carrier, though often overlooked, is at the core of the evolution of cable yarding operations. The implementation of Forestry 4.0 technology is underway, and recent developments align with Forestry 5.0 principles to advance sustainable, safe, and economically viable harvesting in challenging terrain.
In this review, we synthesize knowledge generated over many decades on the main defence responses of Eucalyptus to fungal leaf pathogens with the aim of identifying targets for breeding disease tolerant trees. We highlight physiological and molecular traits associated with host defence in relation to pathogen life-style. Overall, the purpose of this review is to identify resistance mechanisms that offer improved resilience of Eucalyptus plantations in the face of increasing threats by foliar fungal pathogens. The broad aim is to promote sustainable forestry through appropriate selection of resistance traits in trees that are widely planted for commercial timber production.
Eucalyptus is among the most important tree genera planted for commercial timber production worldwide. Numerous foliar pathogens have been reported on these trees in the last 30 years with numbers of recent reports increasing exponentially. The majority of these diseases affect the leaves and shoots of the trees. Knowledge on resistance traits in Eucalyptus to fungal foliar pathogens is limited. This is in part due to the high intra- and inter-species variation in molecular and physiological responses of the host and variation in responses to different pathogens, especially those with different trophic modes. A well-founded understanding of such host responses will provide valuable knowledge required to maintain healthy, sustainable Eucalyptus plantations, especially in the face of changing environmental conditions, where new diseases are caused by fungi previously not considered relevant.
Foliar diseases are among the most important challenges for Eucalyptus plantations globally. The effects of climate change and new or more serious outbreaks present an important threat to the sustainability of Eucalyptus plantations worldwide. Due to restrictions on the use of chemicals, more feasible solutions for disease management lie in selecting planting material with resistance traits. To achieve that goal, it is essential to understand the most important physiological and molecular responses of Eucalyptus to infection by pathogens that infect their foliar tissues. In this review we summarise the available knowledge of the main physiological defence barriers and genetic traits that play key roles in the broad defence against foliar fungal pathogens. Furthermore, we consider defence pathways that are specifically related to the lifestyle and trophic mode of the pathogens. In order to ensure the future sustainability of Eucalyptus plantations, it will be necessary to understand how disease resistance is affected by climate change, as well as the adaptability of the hosts and pathogens to newly emerging environmental conditions.
Quantifying the store and flux of carbon across space and time from trees to forest stands, and ultimately at a global scale, has become paramount for a broad range of applications, including individual tree based allometry, landscape scale forest carbon accounting as well as derivation of globally required climate change related variables. Despite this significant information need, the measurement of forest carbon using field methods remains laborious, expensive and logistically complex.
Laser scanning technologies mounted on terrestrial, unmanned aerial vehicles or drones, aircraft or satellites have revolutionised the estimation of forest carbon at a variety of spatial and temporal scales with each providing detailed and often unique information about the distribution of biomass and carbon within a stand. In this review, we examined the use of laser scanning technologies for this purpose.
To do so we focus on the recently published (within 10 years) peer reviewed literature and consider studies across four information needs, individual tree, stand, regional / national, and global scales. We consider the type of laser scanning data that is typically acquired, data processing pipelines and the products that are produced. After reviewing these studies, we conclude with a discussion of remaining issues associated with the mapping of forest carbon using laser scanning technologies. We also highlight a number of future research directions to further expand the use of this technology for forest carbon mapping globally.
This literature review focused on studies on alternative powertrains and fuels of non-road mobile machinery (NRMM) during the last 15 years and investigated their future potential and expectations. The goal was to evaluate different alternative powertrains based on previous research and highlight the possibilities and challenges of each technology. Additionally, the aim was to conduct a comprehensive overview about the technology development phase of alternative powertrains.
This review covered a total of 115 studies consisting of hybrid, full-electric, biofuels, biogas, and hydrogen solutions. The results highlighted that hybrid and full-electric technologies have the greatest potential to replace conventional diesel engines in the future. The main challenges identified were battery reliability and high technology costs. Regarding biofuel, biogas, and hydrogen, the benefits were mainly lower emissions while the challenges were high costs and low production. Full-electric and hydrogen powertrains were found to reach zero local emissions during operations, while compared to diesel, repair and maintenance caused less emissions of 36–46% during the life cycle with full-electric and hydrogen solutions. With hybrid, biofuels, and biogas powertrains, the emission reduction potential ranged from 37 to 81% during operations and 36–66% during the entire life cycle. The highest Technology Readiness Levels (TRLs) were identified for hybrid and full-electric technologies in industrial machinery (6.9–7.4). The lowest measurable TRL (2.5) was with biogas powered construction machinery. The TRLs of biogas and hydrogen of forest machinery were excluded from this review due to the lack of research.
Alternative powertrains can eventually replace diesel engines, if the challenges with implementation, production, and reliability are solved. Furthermore, the benefits of electric and renewable technologies/fuels are unambiguous from the emission reduction and energy efficiency perspectives. Consequently, we recommend that future research focus especially on the implementation of alternative technologies as well as the improvement of the manufacturing infrastructure.
This review aims to address the specific challenges of forest decline in Mediterranean Fagaceae ecosystems driven by the alien invasive Phytophthora cinnamomi and global changes. In a scenario of climate change and anthropic pressure, this review seeks to offer a comprehensive overview of the current state of P.cinnamomi invasion, focusing on its biology, ecology and epidemiology in different Mediterranean forest ecosystems, and providing an update on diagnosis, impact and current management measures.
Recent studies have significantly advanced our understanding of the decline of Mediterranean Fagaceae forests driven by Phytophthora spp. The introduction of the plant holobiont concept and microbial invasion biology and ecology has reshaped the study of plant–microbe interactions. This perspective, which considers the tree as an ecosystem composed of the tree itself together with its associated microbiome has been pivotal in developing holistic management strategies to mitigate pathogen impacts. The network of interactions between components of the microbial community of healthy and diseased trees, has been the object of several recent studies that highlighted the complex dynamics of host–pathogen interaction and offered the option for biotechnological applications including the use of helper microorganisms and antagonists.
The collaboration among research institutions from Italy, Spain and Portugal has resulted in a detailed review that emphasizes the importance of tailored management protocols for different ecosystems. Engaging stakeholders and citizens in integrated pest management (IPM) strategies has proven crucial for effective forest management. The findings underscore the need for continuous monitoring, innovative treatment methods, and public awareness to mitigate the impacts of Alien Invasive Forest Phytophthoras (AIFPs) and ensure the sustainability of Mediterranean Fagaceae forests.
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：