Pub Date : 2023-12-20DOI: 10.1163/22941932-bja10148
Fernanda Bessa, Vicelina Sousa, T. Quilhó, Helena Pereira
The wood colour variability of 98 tropical species from India (Goa), Mozambique and East Timor was described using CIELab colour parameters and related to wood density and anatomical features. Wood colours were mostly light and yellowish, ranging from 24.0–84.4 for wood lightness, 2.6–20.4 for redness, 1.8–36.6 for yellowness, 2.1–35.9 for chromaticity and 27.5–81.6 for hue angle. Among the colour parameters, the positive correlation between L* and b* was the most significant, followed by a negative correlation between L* and a*, while the positive correlation between a* and b* was non-significant. Positive correlations between L* and both h and C* were also highly significant. CIELab colour parameters were significantly correlated to wood density, the stronger negative correlation was found with L*, followed by the negative correlation with b*. Wood colour was not strongly correlated with the quantitative anatomical features studied showing only weak negative correlations between L* and the fibre wall thickness/fibre width ratio and between b* and fibre length. Wood density was correlated to almost all anatomical features showing the strongest correlations with fibre wall thickness/fibre width ratio and fibre width. The darker-coloured tropical woods showed high wood density, high fibre wall proportion, high vessel frequency and narrow vessels compared to the lighter coloured woods. Overall, wood colour diversity of tropical species could contribute to increase the international timber market by including lesser-known species, which would enhance local development and sustainability of endangered tropical species.
{"title":"Diversity of wood colour in tropical timber species and its relationship with wood density and anatomical features","authors":"Fernanda Bessa, Vicelina Sousa, T. Quilhó, Helena Pereira","doi":"10.1163/22941932-bja10148","DOIUrl":"https://doi.org/10.1163/22941932-bja10148","url":null,"abstract":"\u0000The wood colour variability of 98 tropical species from India (Goa), Mozambique and East Timor was described using CIELab colour parameters and related to wood density and anatomical features. Wood colours were mostly light and yellowish, ranging from 24.0–84.4 for wood lightness, 2.6–20.4 for redness, 1.8–36.6 for yellowness, 2.1–35.9 for chromaticity and 27.5–81.6 for hue angle. Among the colour parameters, the positive correlation between L* and b* was the most significant, followed by a negative correlation between L* and a*, while the positive correlation between a* and b* was non-significant. Positive correlations between L* and both h and C* were also highly significant. CIELab colour parameters were significantly correlated to wood density, the stronger negative correlation was found with L*, followed by the negative correlation with b*. Wood colour was not strongly correlated with the quantitative anatomical features studied showing only weak negative correlations between L* and the fibre wall thickness/fibre width ratio and between b* and fibre length. Wood density was correlated to almost all anatomical features showing the strongest correlations with fibre wall thickness/fibre width ratio and fibre width. The darker-coloured tropical woods showed high wood density, high fibre wall proportion, high vessel frequency and narrow vessels compared to the lighter coloured woods. Overall, wood colour diversity of tropical species could contribute to increase the international timber market by including lesser-known species, which would enhance local development and sustainability of endangered tropical species.","PeriodicalId":55037,"journal":{"name":"IAWA Journal","volume":"81 15","pages":""},"PeriodicalIF":1.9,"publicationDate":"2023-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138956854","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-06DOI: 10.1163/22941932-bja10147
A. Oskolski, F. M. Akinlabi
Fynbos, a shrubland from the Cape Floristic Region in South Africa, is one of five Mediterranean-climate biomes alongside maquis in the Mediterranean Basin, chaparral in California, matorral in Central Chile and kwongan in Southwestern Australia. We compiled the available information on the wood anatomy of 226 species belonging to 65 genera of 14 families that occurred in fynbos and compared this dataset with the published data on wood diversity in Californian chaparral and Israeli maquis. “Carlquist’s Law”, i.e., the association between the ground tissue made of fibre tracheids and low vessel grouping, has been confirmed for the fynbos plants. The lack of ring porosity and very low incidence of semi-ring-porous woods is the most prominent difference of the fynbos from the other two vegetation types. These features are attributed to the paucity of deciduous plants in fynbos which is probably associated with the poor-nutrient soils in this biome. The fynbos differs from chaparral and maquis also in the greatest percentage of the species having no tracheids in their wood as well as with the lowest incidence of helical thickenings on the vessel walls. These differences could be explained by the lower tolerance of fynbos shrubs to seasonal drought due to the relatively mild dry season in this biome. We also found that some differences between fynbos, chaparral, and maquis in the incidences of fibre tracheids and vasicentric/vascular tracheids associated with large vessel groups can be at least partly explained by different systematic compositions of their floras. The higher percentage of distinct growth rings, greater vessel diameter, and lower vessel frequency in maquis compared with fynbos and chaparral can be attributed to a common occurrence of relatively tall trees in this vegetation.
{"title":"Wood structural diversity in fynbos, chaparral, and maquis: a preliminary estimation","authors":"A. Oskolski, F. M. Akinlabi","doi":"10.1163/22941932-bja10147","DOIUrl":"https://doi.org/10.1163/22941932-bja10147","url":null,"abstract":"\u0000Fynbos, a shrubland from the Cape Floristic Region in South Africa, is one of five Mediterranean-climate biomes alongside maquis in the Mediterranean Basin, chaparral in California, matorral in Central Chile and kwongan in Southwestern Australia. We compiled the available information on the wood anatomy of 226 species belonging to 65 genera of 14 families that occurred in fynbos and compared this dataset with the published data on wood diversity in Californian chaparral and Israeli maquis. “Carlquist’s Law”, i.e., the association between the ground tissue made of fibre tracheids and low vessel grouping, has been confirmed for the fynbos plants. The lack of ring porosity and very low incidence of semi-ring-porous woods is the most prominent difference of the fynbos from the other two vegetation types. These features are attributed to the paucity of deciduous plants in fynbos which is probably associated with the poor-nutrient soils in this biome. The fynbos differs from chaparral and maquis also in the greatest percentage of the species having no tracheids in their wood as well as with the lowest incidence of helical thickenings on the vessel walls. These differences could be explained by the lower tolerance of fynbos shrubs to seasonal drought due to the relatively mild dry season in this biome. We also found that some differences between fynbos, chaparral, and maquis in the incidences of fibre tracheids and vasicentric/vascular tracheids associated with large vessel groups can be at least partly explained by different systematic compositions of their floras. The higher percentage of distinct growth rings, greater vessel diameter, and lower vessel frequency in maquis compared with fynbos and chaparral can be attributed to a common occurrence of relatively tall trees in this vegetation.","PeriodicalId":55037,"journal":{"name":"IAWA Journal","volume":"9 6","pages":""},"PeriodicalIF":1.9,"publicationDate":"2023-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138594388","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Barrier and reaction zones are core parts of compartmentalization in trees. However, little is known about the relationship between them. Here, agarwood and barrier zone formation in Aquilaria sinensis trees were studied for the first time using compartmentalization theory. The main results were as follows: (1) Wounding methods had a very important influence on the occurrence of barrier zones in A. sinensis. (2) The barrier zone development process was divided into three phases based on the morphological features. (3) The agarwood resin mainly accreted during the barrier zone lag and division phases; then, after the barrier zone entered the differentiation phase, the resin no longer accreted and even tended to degrade. (4) In the application of the whole-tree agarwood-inducing technique, the barrier zone generally began to appear 10 months after the technique treatment, and the barrier zones were more severe in the lower part of the stem. (5) Considering the agarwood yield, agarwood resin filling degree and ethanol-soluble extract content, the serious barrier zone indeed reduced the agarwood productivity. This study is important for revealing the agarwood and barrier zone formation mechanism in Aquilaria trees. It also provides a good research model for considering the high economic value of agarwood when studying compartmentalization.
{"title":"Barrier zone formation and development in the stems of Aquilaria sinensis (Thymelaeaceae) and the effect on agarwood formation","authors":"Peiwei Liu, Yuxiu Zhang, Yun Yang, Xingning Lin, Songning Lin, Yanqing Deng, Bo Chen, Jianhe Wei","doi":"10.1163/22941932-bja10146","DOIUrl":"https://doi.org/10.1163/22941932-bja10146","url":null,"abstract":"\u0000Barrier and reaction zones are core parts of compartmentalization in trees. However, little is known about the relationship between them. Here, agarwood and barrier zone formation in Aquilaria sinensis trees were studied for the first time using compartmentalization theory. The main results were as follows: (1) Wounding methods had a very important influence on the occurrence of barrier zones in A. sinensis. (2) The barrier zone development process was divided into three phases based on the morphological features. (3) The agarwood resin mainly accreted during the barrier zone lag and division phases; then, after the barrier zone entered the differentiation phase, the resin no longer accreted and even tended to degrade. (4) In the application of the whole-tree agarwood-inducing technique, the barrier zone generally began to appear 10 months after the technique treatment, and the barrier zones were more severe in the lower part of the stem. (5) Considering the agarwood yield, agarwood resin filling degree and ethanol-soluble extract content, the serious barrier zone indeed reduced the agarwood productivity. This study is important for revealing the agarwood and barrier zone formation mechanism in Aquilaria trees. It also provides a good research model for considering the high economic value of agarwood when studying compartmentalization.","PeriodicalId":55037,"journal":{"name":"IAWA Journal","volume":"36 6","pages":""},"PeriodicalIF":1.9,"publicationDate":"2023-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138596850","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-04DOI: 10.1163/22941932-bja10143
Roberto R. Pujana, Juan L. García Massini, S. Noetinger, I. Aramendía
Angiosperm fossil woods of putative Eocene age from Corcovado, Chubut Province are described. They are placed in four taxonomic units: Weinmannioxylon trichospermoides and cf. Caldcluvioxylon of the Cunoniaceae, Myrceugenellites maytenoides of the Myrtaceae, and Nothofagoxylon ruei of the Nothofagaceae. The taxa in the assemblage are in accordance with similar fossil wood assemblages previously described from the Eocene and Oligocene of Patagonia. All the taxa are anatomically similar to trees that live today in Patagonia. Some of the woods show decay patterns by different saproxylic organisms. These include arthropod borings with coprolites and fungal remains in fungi-decayed tissues that are consistent with an active saproxylic community involved in the recycling of wood in the depositional paleoenvironment.
{"title":"Fossil woods from Corcovado (Eocene?), Argentinean Patagonia: angiosperm diversity and biodeterioration","authors":"Roberto R. Pujana, Juan L. García Massini, S. Noetinger, I. Aramendía","doi":"10.1163/22941932-bja10143","DOIUrl":"https://doi.org/10.1163/22941932-bja10143","url":null,"abstract":"\u0000Angiosperm fossil woods of putative Eocene age from Corcovado, Chubut Province are described. They are placed in four taxonomic units: Weinmannioxylon trichospermoides and cf. Caldcluvioxylon of the Cunoniaceae, Myrceugenellites maytenoides of the Myrtaceae, and Nothofagoxylon ruei of the Nothofagaceae. The taxa in the assemblage are in accordance with similar fossil wood assemblages previously described from the Eocene and Oligocene of Patagonia. All the taxa are anatomically similar to trees that live today in Patagonia. Some of the woods show decay patterns by different saproxylic organisms. These include arthropod borings with coprolites and fungal remains in fungi-decayed tissues that are consistent with an active saproxylic community involved in the recycling of wood in the depositional paleoenvironment.","PeriodicalId":55037,"journal":{"name":"IAWA Journal","volume":"51 6","pages":""},"PeriodicalIF":1.9,"publicationDate":"2023-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138602013","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-01DOI: 10.1163/22941932-bja10145
Shan Li, Sen Lu, Chuhuan Yuan, Jing Wang, Junkang Guo
The dimensions and distribution pattern of bordered pits are critical to the xylem water transport function of trees. However, studies on the three-dimensional distribution pattern of pits across xylem growth rings are still limited. Here, Micro-Computed Tomography (Micro-CT) was used to acquire xylem images of two-year-old Platycladus orientalis seedlings. We analyzed the tracheid lumen diameter of 665 tracheids, pit volume, and pit diameter of 11 810 inter-tracheid pits from three radial profiles. The volume ratio of inter-tracheid pits was about 0.90–0.96%. The average pit diameter was 6.8 μm and the average pit volume was 58.9 μm3, and more than 80% of the pits had a diameter of 5–8 μm and a volume of 20–90 μm3. Both the pit diameter and the pit volume increased gradually in the radial direction from the second-year growth ring to the current-year growth ring, and the pit diameter and volume were significantly higher in earlywood than in latewood. The distribution pattern of the tracheid diameter was similar to that of the pit diameter, and the wider the tracheids, the larger the pits. The distribution of bordered pits in P. orientalis may be a critical trait explaining the xylem embolism spread pattern in this species.
{"title":"The three-dimensional distribution of bordered pits across growth rings of stem segment in Platycladus orientalis (Cupressaceae) seedlings","authors":"Shan Li, Sen Lu, Chuhuan Yuan, Jing Wang, Junkang Guo","doi":"10.1163/22941932-bja10145","DOIUrl":"https://doi.org/10.1163/22941932-bja10145","url":null,"abstract":"\u0000The dimensions and distribution pattern of bordered pits are critical to the xylem water transport function of trees. However, studies on the three-dimensional distribution pattern of pits across xylem growth rings are still limited. Here, Micro-Computed Tomography (Micro-CT) was used to acquire xylem images of two-year-old Platycladus orientalis seedlings. We analyzed the tracheid lumen diameter of 665 tracheids, pit volume, and pit diameter of 11 810 inter-tracheid pits from three radial profiles. The volume ratio of inter-tracheid pits was about 0.90–0.96%. The average pit diameter was 6.8 μm and the average pit volume was 58.9 μm3, and more than 80% of the pits had a diameter of 5–8 μm and a volume of 20–90 μm3. Both the pit diameter and the pit volume increased gradually in the radial direction from the second-year growth ring to the current-year growth ring, and the pit diameter and volume were significantly higher in earlywood than in latewood. The distribution pattern of the tracheid diameter was similar to that of the pit diameter, and the wider the tracheids, the larger the pits. The distribution of bordered pits in P. orientalis may be a critical trait explaining the xylem embolism spread pattern in this species.","PeriodicalId":55037,"journal":{"name":"IAWA Journal","volume":" 5","pages":""},"PeriodicalIF":1.9,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138615793","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-22DOI: 10.1163/22941932-bja10142
Nermeen A. Ziada
A petrified wood resembling the modern wood of Mammea africana Sabine is described from the Oligocene Gebel Ahmer Formation from Egypt. The fossil wood is attributed to Mammeoxylon lanneoides Lemoigne according to the xylotomical homologies with the species recorded previously from Ethiopia. The wood anatomy observed in the fossil specimen, along with the climatic information available from the Nearest Living Relative comparison, suggests a tropical humid climate at the site of growth. This is the oldest record of Mammeoxylon Lemoigne in Africa, which contributes towards the understanding of the origin and paleo-dispersal pathways of the genus. A list of 46 Egyptian Oligocene wood species attributed to 11 families is also given.
{"title":"The first record of Mammeoxylon lanneoides Lemoigne (Clusiaceae) from Egypt, with a summary of the Egyptian Oligocene wood flora","authors":"Nermeen A. Ziada","doi":"10.1163/22941932-bja10142","DOIUrl":"https://doi.org/10.1163/22941932-bja10142","url":null,"abstract":"A petrified wood resembling the modern wood of Mammea africana Sabine is described from the Oligocene Gebel Ahmer Formation from Egypt. The fossil wood is attributed to Mammeoxylon lanneoides Lemoigne according to the xylotomical homologies with the species recorded previously from Ethiopia. The wood anatomy observed in the fossil specimen, along with the climatic information available from the Nearest Living Relative comparison, suggests a tropical humid climate at the site of growth. This is the oldest record of Mammeoxylon Lemoigne in Africa, which contributes towards the understanding of the origin and paleo-dispersal pathways of the genus. A list of 46 Egyptian Oligocene wood species attributed to 11 families is also given.","PeriodicalId":55037,"journal":{"name":"IAWA Journal","volume":"13 5","pages":""},"PeriodicalIF":1.9,"publicationDate":"2023-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139246517","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-22DOI: 10.1163/22941932-bja10144
T. Tarelkina, N. Galibina, M. A. Ershova, Sergei A. Moshnikov, K. Nikerova, N. V. Afoshin, L. Semenova
This work is part of a project investigating the heartwood formation process in Scots pine. Despite the economic and ecological importance of pine heartwood (HW), the process of its formation in many respects remains poorly understood. Scientists believe that HW formation in Scots pine begins at 9–20 years, however, systematic studies of HW initiation age in this species have not previously been conducted. Samples were collected from 105 P. sylvestris trees aged 10 to 25 years, growing in the middle and northern taiga subzones, as well as on the border of the northern taiga subzone with the tundra. Samples were taken at the trunk base according to a single technique and processed using two biochemical (peroxidase activity, pinosylvin presence) and two anatomical markers (presence of extractives on the tracheid pit membranes, nuclei disappearance) characterizing different events during HW formation. Biochemical markers showed an overestimation in the number of HW annual rings compared with HW determination based on anatomical criteria by 1–3 years, on average. Attempts to detect peroxidase activity showed a negative result in the inner sapwood annual ring, while detectable pinosylvin accumulation occurred in the transition zone (TZ). We have detected for the first time true HW (without living cells) in Scots pine samples with a cambial age (CA) of 15–17 years. The number of growth rings in TZ and HW in young trees depended on growth conditions. These results are important for understanding the mechanisms of HW formation and developing realistic models of this process, including changing climate conditions.
{"title":"Age of heartwood initiation in trunks of young Pinus sylvestris L. trees in the taiga zone","authors":"T. Tarelkina, N. Galibina, M. A. Ershova, Sergei A. Moshnikov, K. Nikerova, N. V. Afoshin, L. Semenova","doi":"10.1163/22941932-bja10144","DOIUrl":"https://doi.org/10.1163/22941932-bja10144","url":null,"abstract":"This work is part of a project investigating the heartwood formation process in Scots pine. Despite the economic and ecological importance of pine heartwood (HW), the process of its formation in many respects remains poorly understood. Scientists believe that HW formation in Scots pine begins at 9–20 years, however, systematic studies of HW initiation age in this species have not previously been conducted. Samples were collected from 105 P. sylvestris trees aged 10 to 25 years, growing in the middle and northern taiga subzones, as well as on the border of the northern taiga subzone with the tundra. Samples were taken at the trunk base according to a single technique and processed using two biochemical (peroxidase activity, pinosylvin presence) and two anatomical markers (presence of extractives on the tracheid pit membranes, nuclei disappearance) characterizing different events during HW formation. Biochemical markers showed an overestimation in the number of HW annual rings compared with HW determination based on anatomical criteria by 1–3 years, on average. Attempts to detect peroxidase activity showed a negative result in the inner sapwood annual ring, while detectable pinosylvin accumulation occurred in the transition zone (TZ). We have detected for the first time true HW (without living cells) in Scots pine samples with a cambial age (CA) of 15–17 years. The number of growth rings in TZ and HW in young trees depended on growth conditions. These results are important for understanding the mechanisms of HW formation and developing realistic models of this process, including changing climate conditions.","PeriodicalId":55037,"journal":{"name":"IAWA Journal","volume":"3 5","pages":""},"PeriodicalIF":1.9,"publicationDate":"2023-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139246998","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-01DOI: 10.1163/22941932-bja10141
J. Julio Camarero, Xavier Serra-Maluquer, Michele Colangelo, Antonio Gazol, Manuel Pizarro
Summary The climatic significance and ecosystem implications of latewood intra-annual density fluctuations (IADFs) are still not fully understood in Mediterranean ring-porous oak species. To solve this issue, we investigated: (i) the climate drivers of radial growth and latewood IADFs in the Mediterranean oak Quercus faginea , and (ii) whether they were correlated to increased canopy cover and greenness as recorded by the Normalized Difference Vegetation Index (NDVI). IADFs were formed in the mid to late latewood and they were characterized by rows of parenchyma cells. Such IADFs were uncommon and only present in 30–50% of sampled trees during 1999 and 2014, both years characterized by high precipitation in late July and early August. This relationship between IADFs formation and summer wet conditions differed from the conditions that enhance Q. faginea annual growth, wet winter-spring conditions, and low summer temperatures. Furthermore, IADFs formation showed a positive relationship with August NDVI values, indicating a correspondence of canopy greenness with secondary growth reactivation. We conclude that latewood IADFs in Q. faginea are a robust proxy of rare late-summer wet conditions and enhanced canopy activity as reflected by increased August NDVI values. Further monitoring of xylogenesis in other Mediterranean hardwoods along climatic gradients is suggested to mechanistically explain IADF production in seasonally dry biomes.
{"title":"Latewood intra-annual density fluctuations indicate wet summer conditions and enhanced canopy activity in a Mediterranean ring-porous oak","authors":"J. Julio Camarero, Xavier Serra-Maluquer, Michele Colangelo, Antonio Gazol, Manuel Pizarro","doi":"10.1163/22941932-bja10141","DOIUrl":"https://doi.org/10.1163/22941932-bja10141","url":null,"abstract":"Summary The climatic significance and ecosystem implications of latewood intra-annual density fluctuations (IADFs) are still not fully understood in Mediterranean ring-porous oak species. To solve this issue, we investigated: (i) the climate drivers of radial growth and latewood IADFs in the Mediterranean oak Quercus faginea , and (ii) whether they were correlated to increased canopy cover and greenness as recorded by the Normalized Difference Vegetation Index (NDVI). IADFs were formed in the mid to late latewood and they were characterized by rows of parenchyma cells. Such IADFs were uncommon and only present in 30–50% of sampled trees during 1999 and 2014, both years characterized by high precipitation in late July and early August. This relationship between IADFs formation and summer wet conditions differed from the conditions that enhance Q. faginea annual growth, wet winter-spring conditions, and low summer temperatures. Furthermore, IADFs formation showed a positive relationship with August NDVI values, indicating a correspondence of canopy greenness with secondary growth reactivation. We conclude that latewood IADFs in Q. faginea are a robust proxy of rare late-summer wet conditions and enhanced canopy activity as reflected by increased August NDVI values. Further monitoring of xylogenesis in other Mediterranean hardwoods along climatic gradients is suggested to mechanistically explain IADF production in seasonally dry biomes.","PeriodicalId":55037,"journal":{"name":"IAWA Journal","volume":"90 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135372397","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-20DOI: 10.1163/22941932-bja10137
Frederic Lens, Sean M. Gleason, Giovanni Bortolami, Craig Brodersen, Sylvain Delzon, Steven Jansen
Summary Results from comparative and ecological wood anatomy combined with a number of experimental studies on plant hydraulics have led to a pervasive and longstanding assumption that wider-diameter vessels are more vulnerable to drought-induced embolism than narrower vessels. Although we agree that wider vessels tend to be more vulnerable than narrower vessels within stems and within roots across most species, our current understanding of the diameter-vulnerability link does not offer a mechanistic explanation for why increased vessel diameter should consistently lead to greater vulnerability or vice versa. Causes of drought-induced embolism formation and spread likely operate at the nano-level, especially at gas-liquid-surfactant interfaces inside intervessel pit membranes. We evaluate here new perspectives on drought-induced embolism and its key anatomical and physico-chemical drivers, of which vessel diameter is one of the parameters involved, although its linkage to embolism vulnerability is likely indirect. As such, the diameter-vulnerability link does not imply that species with on average wider vessels are consistently more susceptible to drought-induced embolism compared to species with narrower vessels. Scientific priorities for future progress should focus on more accurate predictions of how water transport in plants is affected by drought, which requires a better mechanistic understanding of xylem network topology and biophysical processes at the nano-scale level in individual vessels that determine embolism formation and spread.
{"title":"Comparative anatomy vs mechanistic understanding: how to interpret the diameter-vulnerability link","authors":"Frederic Lens, Sean M. Gleason, Giovanni Bortolami, Craig Brodersen, Sylvain Delzon, Steven Jansen","doi":"10.1163/22941932-bja10137","DOIUrl":"https://doi.org/10.1163/22941932-bja10137","url":null,"abstract":"Summary Results from comparative and ecological wood anatomy combined with a number of experimental studies on plant hydraulics have led to a pervasive and longstanding assumption that wider-diameter vessels are more vulnerable to drought-induced embolism than narrower vessels. Although we agree that wider vessels tend to be more vulnerable than narrower vessels within stems and within roots across most species, our current understanding of the diameter-vulnerability link does not offer a mechanistic explanation for why increased vessel diameter should consistently lead to greater vulnerability or vice versa. Causes of drought-induced embolism formation and spread likely operate at the nano-level, especially at gas-liquid-surfactant interfaces inside intervessel pit membranes. We evaluate here new perspectives on drought-induced embolism and its key anatomical and physico-chemical drivers, of which vessel diameter is one of the parameters involved, although its linkage to embolism vulnerability is likely indirect. As such, the diameter-vulnerability link does not imply that species with on average wider vessels are consistently more susceptible to drought-induced embolism compared to species with narrower vessels. Scientific priorities for future progress should focus on more accurate predictions of how water transport in plants is affected by drought, which requires a better mechanistic understanding of xylem network topology and biophysical processes at the nano-scale level in individual vessels that determine embolism formation and spread.","PeriodicalId":55037,"journal":{"name":"IAWA Journal","volume":"168 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135618835","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-20DOI: 10.1163/22941932-bja10139
Harshita Bhatia, Gaurav Srivastava, R.C. Mehrotra
Summary The order Boraginales of the Lamiids clade encompasses a diverse group of plants that currently has a global distribution. Its fossil record is scanty. Herein we report a fossil wood of Cordia L. of the family Cordiaceae from the Tipam Sandstone (late Miocene) sediments of Assam, northeast India. This finding not only throws light on the phytogeography and diversification of the Cordiaceae, but also provides valuable insights into the Neogene vegetation of the region.
{"title":"Cordiaceae wood from the Miocene sediments of northeast India and its phytogeographical significance","authors":"Harshita Bhatia, Gaurav Srivastava, R.C. Mehrotra","doi":"10.1163/22941932-bja10139","DOIUrl":"https://doi.org/10.1163/22941932-bja10139","url":null,"abstract":"Summary The order Boraginales of the Lamiids clade encompasses a diverse group of plants that currently has a global distribution. Its fossil record is scanty. Herein we report a fossil wood of Cordia L. of the family Cordiaceae from the Tipam Sandstone (late Miocene) sediments of Assam, northeast India. This finding not only throws light on the phytogeography and diversification of the Cordiaceae, but also provides valuable insights into the Neogene vegetation of the region.","PeriodicalId":55037,"journal":{"name":"IAWA Journal","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135617778","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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