المؤلفون: Salomón, Roberto L., Miranda, José Carlos, Rubio-Cuadrado, Álvaro, Sobrino-Plata, Juan, Rodríguez Calcerrada, Jesús, López, Rosana, Gil, Luis, Valbuena-Carabaña, María

المساهمون: Comunidad de Madrid, Ministerio de Ciencia, Innovación y Universidades (España), Agencia Estatal de Investigación (España), Organismo Autónomo Parques Nacionales (España), European Commission, Rubio-Cuadrado, Álvaro

مصطلحات موضوعية: Coppice management, Dendrochronology, Acorn production, Silviculture, Tree decline, Vegetative regeneration

الوصف: © 2024 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0Test/). ; Widespread tree growth decline and absence of acorn production are observed in formerly coppiced Quercus pyrenaica stands. Attempts to convert oak coppices into high forests by thinning have failed to date, possibly due to the massive root system developed by trees after centuries of coppicing. We tested root trenching and stem girdling as silvicultural treatments to mitigate this hypothetical root-to-shoot imbalance and enhance the physiological performance of multi-stemmed clonal trees. We expected that severing the roots within a clone by trenching would reduce root respiratory carbon losses. Alternatively, stem girdling would increase carbon availability above the girdled zone, whilst the communal root system is maintained by non-girdled stems. After clonal structure delineation in a one-hectare experimental plot, root trenching and stem girdling were applied to stems belonging to different clones. Twig hydraulic traits, leaf water potential, non-structural carbohydrates (NSC) concentration in twigs, stems and roots, stem xylem [CO2] as an indicator of root respiration, stem growth, and acorn production were discretely monitored up to 12 years after treatment application for comparison with control stems. Stem girdling led to short-term enhancements in NSC pools above the girdled zone. However, hydraulic dysfunction symptoms and canopy dieback were observed four years after girdling, eventually causing mortality. Root trenching initially increased root respiration and reduced stem growth without an apparent decline in the hydraulic function and NSC pools above-ground. Ten years after trenching, stem [NSC] increased while stem growth limitations diminished. Although not statistically significant, slight enhancements in acorn production were observed 6 and 12 years after trenching. We discourage stem girdling as a silvicultural practice to mitigate ...

وصف الملف: application/pdf

العلاقة: #PLACEHOLDER_PARENT_METADATA_VALUE#; P2009/AMB-1668; info:eu-repo/grantAgreement/AEI/Plan Estatal de Investigación Científica y Técnica y de Innovación 2017-2020/PID2020-117478RA-I00/ES/DECAIMIENTO DE MELOJARES (QUERCUS PYRENAICA WILLD.): ALCANCE, ORIGEN Y ADAPTACION AL CAMBIO CLIMATICO /; info:eu-repo/grantAgreement/AEI//RYC2021-032467-I; Publisher's version; https://doi.org/10.1016/j.foreco.2024.121722Test; Sí; Forest Ecology and Management 555: 121722 (2024); http://hdl.handle.net/10261/354619Test

الإتاحة: https://doi.org/10.1016/j.foreco.2024.121722Test
http://hdl.handle.net/10261/354619Test

المؤلفون: Chengwei Luo, Yuli Yang, Zhiming Xin, Junran Li, Xiaoxiao Jia, Guangpeng Fan, Junying Zhu, Jindui Song, Zhou Wang, Huijie Xiao

المصدر: Remote Sensing, Vol 15, Iss 18, p 4508 (2023)

مصطلحات موضوعية: desert oases, protective functions, tree decline, remote sensing, laser scanning, spectrum, Science

الوصف: The deterioration of farmland shelterbelts in the Ulan Buh desert oases could weaken their protective functions. Therefore, an accurate method is essential to assess tree decline degree in order to guide the rejuvenation and transformation of these shelterbelts. This study selected three typical farmland shelterbelts in the Ulan Buh desert oases as the objects. Terrestrial laser scanning (TLS) and airborne hyperspectral imagery (AHI) were used to acquire point cloud data and detailed spectral information of trees. Point cloud and spectral characteristics of trees with varying decline levels were analyzed. Six models were constructed to identify decline degree of shelterbelts, and model accuracy was evaluated. The coefficient of determination between the structural parameters of trees extracted by TLS and field measurements ranged from 0.76 to 0.94. Healthy trees outperformed declining trees in structural parameters, particularly in tridimensional green biomass and crown projection area. Spectral reflectance changes in the 740–950 nm band were evident among the three tree types with different decline levels, decreasing significantly with increased decline level. Among the TLS-derived feature parameters, the canopy relief ratio of tree points and point cloud density strongly correlated with the degree of tree decline. The plant senescence reflectance index and normalized difference vegetation index exhibited the closest correlation with tree decline in AHI data. The average accuracy of the models constructed based on the feature parameters of LiDAR, AHI, and the combination of both of them were 0.77, 0.61, and 0.81, respectively. The light gradient-boosting machine model utilizing TLS–AHI comprehensive feature parameters accurately determined tree decline. This study highlights the efficacy of employing feature parameters derived from TLS alone to accurately identify tree decline. Combining feature parameters from the TLS and AHI enhances the precision of tree decline identification. This approach offers guidance for decisions regarding the renewal and transformation of declining farmland shelterbelts.

وصف الملف: electronic resource

العلاقة: https://www.mdpi.com/2072-4292/15/18/4508Test; https://doaj.org/toc/2072-4292Test

الوصول الحر: https://doaj.org/article/cb3b50d8ad7e42989b1b7cace731dd00Test

المؤلفون: Forough Soheili, Hazandy Abdul-Hamid, Isaac Almasi, Mehdi Heydari, Afsaneh Tongo, Stephen Woodward, Hamid Reza Naji

المصدر: Plants; Volume 12; Issue 2; Pages: 377

مصطلحات موضوعية: drought, tree decline, Quercus brantii, cellular characteristics, calcium oxalate crystals

جغرافية الموضوع: agris

الوصف: Drought has serious effects on forests, especially semi-arid and arid forests, around the world. Zagros Forest in Iran has been severely affected by drought, which has led to the decline of the most common tree species, Persian oak (Quercusbrantii). The objective of this study was to determine the effects of drought on the anatomical structure of Persian oak. Three healthy and three declined trees were sampled from each of two forest sites in Ilam Forest. Discs were cut at breast height, and three sapwood blocks were taken near the bark of each tree for sectioning. The anatomical characteristics measured included fiber length (FL), fiber wall thickness (FWT), number of axial parenchymal cells (NPC), ray number (RN), ray width (RW), and number of calcium oxalate crystals. Differences between healthy and declined trees were observed in the abundance of NPC and in RN, FL, and FWT, while no differences occurred in the number of oxalate crystals. The decline had uncertain effects on the FL of trees from sites A and B, which showed values of 700.5 and 837.3 μm compared with 592.7 and 919.6 μm in healthy trees. However, the decline resulted in an increase in the FWT of trees from sites A and B (9.33 and 11.53 μm) compared with healthy trees (5.23 and 9.56 μm). NPC, RN, and RW also increased in declined individuals from sites A and B (28.40 and 28.40 mm−1; 41.06 and 48.60 mm−1; 18.60 and 23.20 μm, respectively) compared with healthy trees (20.50 and 19.63 mm−2; 31.60 and 28.30 mm−2; 17.93 and 15.30 μm, respectively). Thus, drought caused measurable changes in the anatomical characteristics of declined trees compared with healthy trees.

وصف الملف: application/pdf

العلاقة: Plant Response to Abiotic Stress and Climate Change; https://dx.doi.org/10.3390/plants12020377Test

الإتاحة: https://doi.org/10.3390/plants12020377Test

المؤلفون: Anatoly Zhezhkun, Ihor Porohnyach

المصدر: Наукові праці Лісівничої академії наук України, Iss 21, Pp 126-134 (2020)

مصطلحات موضوعية: tree decline, stem pests, categories of tree health condition, sanitary felling., Forestry, SD1-669.5

الوصف: The features of the spread of pine stands decline in the Eastern Polissya of Ukraine under biotic and abiotic factors impact are generalized and highlighted. The works were carried out according to the generally accepted methods of forest pathological and forestry-taxation research on the forest pathological routes in pine stands with signs of tree decline and in foci of tree mortality, at the permanent and temporary plots in the dieback foci. To determine the species composition, population indices, and population density of stem insects in the dieback foci, periodic decadal assessments were carried out in the exposed pheromone traps and in different parts of the stem of model trees according to entomological research methods. It is determined that the drying of pine trees in previous years was mainly due to damage of trees by the pathogen of the root rot Heterobasidion annosum (Fries) Bref. At the beginning of the growing season in 2015 the reconnaissance surveys revealed the spread of pathological drying of pine stands. After periodic prolonged droughts during the vegetation periods of 2015–2017, in the following years, the intensity of the group formation , curtain dieback foci increased with a tendency to continuous drying of pine stands. Mainly pines of middle-aged and older age, artificial origin, pure composition, simple form, less stand density in all types of forests dried. Dieback foci initially appeared near the forest edge, narrow strips and low-density pine stands, moving to other pines from the south-western to the north-eastern part of Eastern Polissya. Area of pine stands with dieback foci in the study region annually amounted to 12.5–17.1 thousand ha (6–8% of their total area). Based on detailed forest pathological inspection, it was found that tree weakening and the dieback of stands occurred due to the mass propagation of stem insects – Ips acuminatus Gyll. and Ips sexdentatus Boern. It was determined that the population density of the young generation of Ips acuminatus during 2017–2018 exceeded the average population indices by 10 or more times with production up to 100 juvenile beetles per dm2 of populated stem area. The possibility of three generations of Ips acuminatus development per year under favorable conditions has been revealed. Due to unfavorable weather conditions for wintering of stem insects and exceeding the long-term precipitation with a decrease in temperature at the beginning of the growing season in 2019 the density of bark beetle populations decreased significantly (2–3 times) with the formation of only single and group dieback foci. The number of insects decreased due to the restoration of water supply to pine trees, which made it possible to maintain sufficient resin release and flooding of mother and larval galleries with adult beetles. With sufficient moisture, pine trees of the 1st-2nd categories of health condition are able to maintain a stable level of resin productivity for a long time compared to weakened trees. Therefore, it is important to reproduce more resistant pine stands of mixed composition, natural origin, complex shape structure. For the first time, it has been found that very weakened and drying up pine trees are able to rapidly but briefly release more resin than more viable trees. To reduce and overcome the effects of pine forests dieback, a set of forestry and protective measures should be applied: sanitary felling, attraction of birds and other entomophagous animals, application of mineral fertilizers, and stem injections of the most valuable trees.

وصف الملف: electronic resource

العلاقة: http://fasu.nltu.edu.ua/index.php/nplanu/article/view/632Test; https://doaj.org/toc/1991-606XTest; https://doaj.org/toc/2616-5015Test

الوصول الحر: https://doaj.org/article/2d75fbc9f81546d78dfc0558fca07aa4Test

المؤلفون: Dao Ngoc Quang, Pham Quang Thu, Le Van Binh, Duy Long Pham, Tran Viet Thang, Trang A. Tong, Nguyen Hoai Thu, Nguyen Van Thanh, Nguyen Quoc Thong, Bui Quang Tiep, Bernard Dell

المصدر: Horticulturae, Vol 8, Iss 12, p 1219 (2022)

مصطلحات موضوعية: Docynia indica, insect pest, Bacchisa medioviolacea, fruit tree decline, upland horticulture, rural livelihood, Plant culture, SB1-1110

الوصف: The wood-borer Bacchisa medioviolacea Breuning (Coleoptera: Cerambycidae) is identified as a major new pest of Docynia indica (Rosales: Rosaceae) orchards in the northwest mountainous provinces of Vietnam. The life cycle extends over two years (721.7 days ± 17.6 days), with overwintering as larvae. Adults emerge and disperse in summer. Females lay 6–12 eggs during an oviposition period of 2–3 days, and the incubation period ranges from 27 to 38 days. The larval and pupal periods take 554–701 days and 40–59 days, respectively. Adults survive for 12–23 days. In 2019, the damage incidence (P%) and the damage index (DI) in Yen Bai, Lao Cai, Lai Chau, and Dien Bien provinces ranged from 43.5% to 71.6% and 0.80 to 1.78, respectively. Further research on the distribution and host range of B. medioviolacea is required to help formulate a management strategy for this new orchard pest.

وصف الملف: electronic resource

العلاقة: https://www.mdpi.com/2311-7524/8/12/1219Test; https://doaj.org/toc/2311-7524Test

الوصول الحر: https://doaj.org/article/95a74bbcde214e6d93596012c059c95bTest

المؤلفون: Jing-Ming Yan, Yong-Gang Li, Bagila Maisupova, Xiao-Bing Zhou, Jing Zhang, Hui-Liang Liu, Ben-Feng Yin, Yong-Xin Zang, Ye Tao, Yuan-Ming Zhang

المصدر: Global Ecology and Conservation, Vol 33, Iss , Pp e01998- (2022)

مصطلحات موضوعية: Malus sieversii, Plant trait network, Nutrient stoichiometry, Growth status, Tree decline, Soil factor, Ecology, QH540-549.5

الوصف: Malus sieversii (wild apple trees) is a tertiary relict tree species and a key ancestor of the cultivated apple trees today. In recent years, serious growth decline and individual death have occurred for M. sieversii. Whether growth decline would lead to the change in twig (composed of leaves and one-year stem) functional traits and their associations of wild apple trees remains unclear. Two long-term monitoring plots (1 hm2) for severely declined and relatively healthy wild apple trees, respectively, were set up in Yili Valley, China. Based on two-year investigations, the differences in tree functional traits and interrelations between the two plots and the influencing factors were analyzed. The crown projective cover, dead branch percentage, and fruit yield were markedly different between two sites and two years. Leaf nitrogen and phosphorous concentrations of declined trees were generally less than healthy trees, although the soil of the former was more fertile. The nitrogen was more susceptible to the stressing, especially for declined trees. Concentrations of stem nitrogen, phosphorous, and potassium and leaf potassium were relatively stable in both plots. The plant trait network analysis indicated that leaf nitrogen (per unit area) that promoted plant growth was the hub trait (meaning that it is correlated with most traits) for healthy trees, while leaf potassium (per unit mass) that related to resistance enhancement became the hub trait for declined trees. Meanwhile, the covariant characteristics of twig traits between the two plots differed obviously, and the soil-trait and growth-trait correlations became more negative for declined trees than healthy trees, indicating that intra-trait and environment-trait associations had changed greatly when trees declined. The ordination analysis revealed that total and available soil nitrogen, phosphorous, and total potassium, pH and plant growth parameters significantly influenced twig traits. Our results demonstrated that twig functional traits and their interrelations of wild apple trees can indicate tree decline trend. We strongly recommend that managers should take measures to prevent the decline of healthy wild apple trees as soon as possible to realize the sustainable existence of this precious germplasm resource. The results provide a theoretical support for scientific management of wild apple populations in the Tianshan Mountains in Central Asia.

وصف الملف: electronic resource

العلاقة: http://www.sciencedirect.com/science/article/pii/S2351989421005485Test; https://doaj.org/toc/2351-9894Test

الوصول الحر: https://doaj.org/article/e635018722f34457971773ad68183519Test

المؤلفون: Burgess, Treena, I., Oliva, Jonas, Sapsford, Sarah J., Sakalidis, Monique L., Balocchi, Felipe, Paap, Trudy

مصطلحات موضوعية: Abies alba, Araucaria araucana, Corymbia calophylla, Global change, Pinus strobus, Tree decline, SDG-15: Life on land

الوصف: PURPOSE OF REVIEW : Human-caused global change is fundamentally altering natural forest ecosystems. More trees are exhibiting a wide range of symptoms indicative of poor vigour, particularly stressed species at the edge of their native ranges and stands growing on marginal sites. This review will focus on complex tree diseases (declines) caused by native pathogens and the key environmental drivers that contribute to this phenomenon. These systems are frequently complex, with multiple drivers at work. RECENT FINDINGS : Using four cases studies on different continents, we explored the direct and indirect environmental drivers underlying these decline syndromes. Although climate and weather events seem to be usually associated with forest decline, we found that environmental disturbance by either forest management or land-use changes is also a global predisposing factor of decline which deserves more attention. Changes in land use have directly benefited pathogens such as root rots in the Pyrenees (Spain) or indirectly by making the environment more conducive for canker and foliar diseases in Australia and the USA. Focus on land-use changes could improve understanding of current decline problems such as those affecting Araucaria in Chile. SUMMARY : The next century will almost certainly see an unprecedented rise in forest pathogen epidemics, requiring a proactive rather than reactive response. Diseases caused by native pathogens with complex aetiologies will become more common, and recognising, characterising and managing these epidemics are difficult because native pathogens are frequently already widespread, and eradication is not feasible. We need to start approaching these issues from a ‘whole ecosystem’ perspective, highlighting the many aspects and entanglements of forest declines and allowing us to respond with management options tailored to each scenario. The approach proposed here provides logical steps based on six questions to untangle the direct and indirect environmental drivers of tree declines. ...

وصف الملف: application/pdf

العلاقة: Burgess, T.I., Oliva, J., Sapsford, S.J. et al. Anthropogenic Disturbances and the Emergence of Native Diseases: a Threat to Forest Health. Current Forestry Reports 8, 111–123 (2022). https://doi.org/10.1007/s40725-022-00163-0Test.; 2198-6436 (online); http://hdl.handle.net/2263/93218Test

الإتاحة: https://doi.org/10.1007/s40725-022-00163-0Test
http://hdl.handle.net/2263/93218Test

المؤلفون: Mantas, Vasco, Fonseca, Luís, Baltazar, Elsa, Canhoto, Jorge, Abrantes, Isabel

مصطلحات موضوعية: machine-learning, pinewood nematode, pine wilt disease, remote sensing, Sentinel-2, tree decline

الوصف: Moderate-resolution satellite imagery is essential to detect conifer tree decline on a regional scale and address the threat caused by pinewood nematode (PWN), (Bursaphelenchus xylophilus. This is a quarantine organism responsible for pine wilt disease (PWD), which has caused substantial ecological and economic losses in the maritime pine (Pinus pinaster) forests of Portugal. This study describes the first instance of a pre-operational algorithm applied to Sentinel-2 imagery to detect PWD-compatible decline in maritime pine. The Random Forest model relied on a pre-wilting and an in-season image, calibrated with data from a 24-month long field campaign enhanced withWorldview- 3 data and the analysis of biological samples (hyperspectral reflectance, pigment quantification in needles, and PWN identification). Independent validation results attested to the good performance of the model with an overall accuracy of 95%, particularly when decline affects more than 30% of the 100 m2 pixel of Sentinel-2. Spectral angle mapper applied to hyperspectral measurements suggested that PWN infection cannot be separated from other drivers of decline in the visible-near infrared domain. Our algorithm can be employed to detect regional decline trends and inform subsequent aerial and field surveys, to further investigate decline hotspots.

العلاقة: Horizon 2020 Grant Agreement 776026; ‘Monitorizar para Decidir e Valorizar’, funded by Programa PROMOVE of BPI/Fundação La Caixa; POINTERS (PTDC/ASP-SIL/31999/2017); ReNATURE (Centro-01-0145-FEDER-000007).; UIDB/04004/2020; http://hdl.handle.net/10316/100506Test

الإتاحة: https://doi.org/10.3390/rs14092028Test
http://hdl.handle.net/10316/100506Test

المؤلفون: Vasco Mantas, Luís Fonseca, Elsa Baltazar, Jorge Canhoto, Isabel Abrantes

المصدر: Remote Sensing; Volume 14; Issue 9; Pages: 2028

مصطلحات موضوعية: machine-learning, pinewood nematode, pine wilt disease, remote sensing, Sentinel-2, tree decline

جغرافية الموضوع: agris

الوصف: Moderate-resolution satellite imagery is essential to detect conifer tree decline on a regional scale and address the threat caused by pinewood nematode (PWN), (Bursaphelenchus xylophilus. This is a quarantine organism responsible for pine wilt disease (PWD), which has caused substantial ecological and economic losses in the maritime pine (Pinus pinaster) forests of Portugal. This study describes the first instance of a pre-operational algorithm applied to Sentinel-2 imagery to detect PWD-compatible decline in maritime pine. The Random Forest model relied on a pre-wilting and an in-season image, calibrated with data from a 24-month long field campaign enhanced with Worldview-3 data and the analysis of biological samples (hyperspectral reflectance, pigment quantification in needles, and PWN identification). Independent validation results attested to the good performance of the model with an overall accuracy of 95%, particularly when decline affects more than 30% of the 100 m2 pixel of Sentinel-2. Spectral angle mapper applied to hyperspectral measurements suggested that PWN infection cannot be separated from other drivers of decline in the visible-near infrared domain. Our algorithm can be employed to detect regional decline trends and inform subsequent aerial and field surveys, to further investigate decline hotspots.

وصف الملف: application/pdf

العلاقة: Forest Remote Sensing; https://dx.doi.org/10.3390/rs14092028Test

الإتاحة: https://doi.org/10.3390/rs14092028Test

المؤلفون: Marziye Ghasemi, Hooman Latifi, Elham Shafeian, Hamed Naghavi, Mehdi Pourhashemi

مصطلحات موضوعية: Biotechnology, Inorganic Chemistry, Plant Biology, Environmental Sciences not elsewhere classified, Biological Sciences not elsewhere classified, Mathematical Sciences not elsewhere classified, Information Systems not elsewhere classified, Tree decline, data fusion, linear spectral unmixing, UAV-RGB, Sentinel-2, Semi-arid vegetation

الوصف: Remote sensing-assisted monitoring of forest health entails methods that can provide up-to-date and accurate information on decline and mortality of individual trees, while maintaining time and cost efficiency. However, the trade-off of applying consumer-grade UAV-RGB data as the most affordable and accessible data source at the catchment level is constrained by its poor spectral information content. We developed a method based on the fusion of UAV-RGB data with space-borne Sentinel-2 Multispectral Instrument (MSI) at the level of tree crowns, with the specific target of supporting studies on semi-arid tree decline. We applied linear spectral unmixing (Spectral Unmixing-Based data Fusion method, LSUBF) by considering a limited number of endmembers and calculating the abundances (fractional covers) from the UAV data, and evaluated the results by high-resolution MSI space-borne data including SPOT-6 (1.5 m spatial resolution) and PlanetScope (3 m spatial resolution). This method suggested an increase in the coefficient of determination of the applied generalized additive model for decline severity estimation at tree crown level from 0.61 to 0.69, while it was improved from 0.70 to 0.91 when fitting a non-parametric random forest model. The results of sensitivity analysis demonstrated that the additional spectral information obtained from the proposed method results in higher accuracy in estimating decline severity. We suggest this method as a cost-effective alternative to monitor periodical tree decline, in particular across semi-arid ecosystems.

العلاقة: https://figshare.com/articles/dataset/A_novel_linear_spectral_unmixing-based_method_for_tree_decline_monitoring_by_fusing_UAV-RGB_and_optical_space-borne_data/25163665Test

الإتاحة: https://doi.org/10.6084/m9.figshare.25163665.v1Test
https://figshare.com/articles/dataset/A_novel_linear_spectral_unmixing-based_method_for_tree_decline_monitoring_by_fusing_UAV-RGB_and_optical_space-borne_data/25163665Test