The Experts below are selected from a list of 567 Experts worldwide ranked by ideXlab platform
Joseph S. Elkinton - One of the best experts on this subject based on the ideXlab platform.
-
molecular placement of an outbreak causing gall wasp zapatella davisae hymenoptera cynipidae with comments on phylogenetic arrangements in the tribe cynipini
Journal of Entomological Science, 2021Co-Authors: Jeremy C Andersen, Monica J. Davis, Katherine N Schick, Joseph S. ElkintonAbstract:Gall wasps (Hymenoptera: Cynipidae) have fascinated researchers for centuries due to the elaborate diversity of charismatic galls they produce, the presence of unique reproductive systems (e.g., a form of cyclical parthenogenesis), the possible convergent evolution of semiparasitic gall wasp forms (i.e., “inquilines”), and their multitrophic interactions. While many classifications for gall wasps have been proposed, recent DNA sequence efforts combined with taxonomic revisions are beginning to clarify the evolutionary relationships of this group. To date, however, a well resolved phylogeny is lacking, complicating the study of outbreak-causing pest species. Outbreaks by one such species, the black oak gall wasp, Zapatella davisae Buffington & Melika (Hymenoptera: Cynipidae: Cynipini), have led to extensive damage and mortality of black oaks, Quercus Velutina L. (Fagales: Fagaceae), in the northeastern United States. Here we sequenced fragments of the nuclear ribosomal gene 28S, and the nuclear protein coding gene long-wavelength opsin from samples of Z. davisae collected on Cape Cod, MA, and Long Island, NY. Using these sequences and sequences previously published from the mitochondrial locus cytochrome b, we performed Bayesian and maximum likelihood multilocus phylogenetic reconstructions based on a concatenated alignment including species of gall wasps in the tribe Cynipini from which all three loci were present in the GenBank database. Confirming morphological work, we find that Z. davisae is most closely related to species in the genera Callirhytis and Neuroterus, and appears to be a basal member of the “Quercus” section of the tribe Cynipini. We find that recent generic reclassifications within the Cynipini have made great progress towards clarifying the taxonomic relationships of species of gall-inducing wasps in this tribe, and we comment on several classifications that require additional research.
-
rise and fall of an oak gall wasp hymenoptera cynipidae outbreak in massachusetts
Environmental Entomology, 2019Co-Authors: Cameron J Smithfreedman, Katherine N Schick, Jeremy C Andersen, Brian P Griffin, Joseph S. ElkintonAbstract:The recently described oak gall wasp Zapatella davisae Buffington & Melika (Hymenoptera: Cynipidae) has caused extensive damage and mortality to black oak trees, Quercus Velutina L. (Fagales: Fagaceae), in coastal parts of New England, United States. Like many newly described and/or newly introduced species, it is unclear how long populations of Z. davisae have existed in this region. However, as this species forms galls on the woody-tissue of its host, it may be possible to obtain historical information about changes in its population size by examining the presence of galls in relation to annual growth nodes. Here, we explore the utility of this approach to determine population size changes in Z. davisae densities on Nantucket, Martha's Vineyard, and Cape Cod, Massachusetts, through dissection of black oak branches. In addition, we calculated parasitism rates during the years of study and obtained morphological and molecular identifications for the parasitoids associated with Z. davisae. Our results show significant changes in population sizes, with higher levels of parasitism at sites on Martha's Vineyard and Cape Cod compared to sites on Nantucket. In addition, morphological examinations, in combination with DNA sequencing, identified the associated parasitoids as five species in the genus Sycophila Walker (Hymenoptera: Eurytomidae). We comment that considerable morphological variation within several of these recovered species was observed, present the first record of males for a species from which only females have been described, and suggest that future work is required to clarify the species boundaries for this important parasitoid group.
-
development of microsatellite markers for an outbreaking species of oak gall wasp zapatella davisae hymenoptera cynipidae in the northeastern united states
Bulletin of Entomological Research, 2019Co-Authors: Jeremy C Andersen, Monica J. Davis, C P Camp, N P Havill, Joseph S. ElkintonAbstract:Populations of the recently described black oak gall wasp, Zapatella davisae Buffington (Hymenoptera: Cynipidae), have been identified as the cause of extensive tree damage and mortality to black oaks, Quercus Velutina Lamarck (Fagales: Fagaceae), in the northeastern United States. Relatively little is known, however, about the distribution, phylogenetic placement, and lifecycle of this important tree pest. Therefore, we conducted next-generation sequencing using the Ion Torrent™ PGM (ThermoFisher Scientific, Inc.) platform to develop genomic resources for the study of Z. davisae and for other closely related species of oak gall wasps. Individual sequence reads were aligned, assembled into unique contigs, and the contigs were then utilized for the in silico isolation and development of microsatellite markers. In total, we screened 36 candidate microsatellite loci, of which 23 amplified consistently (five polymorphic and 18 monomorphic). We then examined whether the polymorphic loci could be used to infer whether populations of Z. davisae from Cape Cod and Nantucket are sexual or asexual by calculating several metrics of genetic diversity that might indicate the mode of reproduction. These included testing for statistical deviations from Hardy–Weinberg equilibrium (HWE) and for linkage disequilibrium (LD), observations for the presence of the Meselson effect, and by calculating the probability that clonal individuals are more prevalent than would be expected in a randomly mating population. While we found significant deviations from HWE and more clonal individuals than expected, our estimates of the Meselson effect were inconclusive due to limited sampling, and we found no evidence of LD. Therefore, the sexual/asexual status of Z. davisae populations remains uncertain.
-
identification of the parasitoid community associated with an outbreaking gall wasp zapatella davisae and their relative abundances in new england and long island new york
Ecology and Evolution, 2019Co-Authors: Monica J. Davis, Jeremy C Andersen, Joseph S. ElkintonAbstract:Gall wasps (Hymenoptera: Cynipidae) are phytophagous insects that often go unnoticed; however, when they are introduced to a new area or released from their natural enemies, they have the capacity to outbreak and cause extensive foliar damage. One such outbreaking pest, Zapatella davisae (Cynipidae: Cynipini), causes significant damage and mortality to black oak, Quercus Velutina, in the northeastern United States. In this study, we aimed to identify the parasitoid community associated with Z. davisae, compare differences in percent parasitism of Z. davisae in Cape Cod and Long Island, and determine which parasitoid species contribute most to parasitism in each region. From both locations, we reared parasitoids, identified morphological groups, analyzed percent parasitism rates for each group, and used DNA barcoding to provide species-level identifications. On Long Island, there was nearly 100% parasitism in 2015 followed by a near total collapse of the population in 2016. In contrast, parasitism rates were lower and remained consistent on Cape Cod between 2015 and 2016, which may explain the greater canopy damage observed in that region. Species of Sycophila were the dominant parasitoids, with one species Sycophila nr. novascotiae representing ~65% of reared parasitoids from Long Island, and two species of Sycophila (S. nr. novascotiae and S. foliatae) with near equal representations on Cape Cod. In order to manage an insect pest, it is important to understand factors that influence its mortality and survival. An understanding of how these infestations progress overtime can help predict the impact that newer infestations in Nantucket, MA, and coastal Rhode Island will have on black oak populations and will aid in the management of this rapidly spreading gall wasp pest.
-
Efficacy of Two Systemic Insecticides With Stem Gall Wasp, Zapatella davisae (Hymenoptera: Cynipidae) on Black Oak.
Journal of economic entomology, 2018Co-Authors: Monica J. Davis, Joseph S. ElkintonAbstract:Black oak, Quercus Velutina Lamarck, is the dominant deciduous tree on Cape Cod, Nantucket, and Martha’s Vineyard, Massachusetts, and in recent years it has experienced widespread mortality and severe canopy loss due to infestations of a stem gall wasp, Zapatella davisae Buffington and Melika (Hymenoptera: Cynipidae). A single application of systemic insecticides emamectin benzoate and imidacloprid was found to reduce or prevent further accumulation of Z. davisae damage on infested black oak during a 1-yr trial.
Monica J. Davis - One of the best experts on this subject based on the ideXlab platform.
-
molecular placement of an outbreak causing gall wasp zapatella davisae hymenoptera cynipidae with comments on phylogenetic arrangements in the tribe cynipini
Journal of Entomological Science, 2021Co-Authors: Jeremy C Andersen, Monica J. Davis, Katherine N Schick, Joseph S. ElkintonAbstract:Gall wasps (Hymenoptera: Cynipidae) have fascinated researchers for centuries due to the elaborate diversity of charismatic galls they produce, the presence of unique reproductive systems (e.g., a form of cyclical parthenogenesis), the possible convergent evolution of semiparasitic gall wasp forms (i.e., “inquilines”), and their multitrophic interactions. While many classifications for gall wasps have been proposed, recent DNA sequence efforts combined with taxonomic revisions are beginning to clarify the evolutionary relationships of this group. To date, however, a well resolved phylogeny is lacking, complicating the study of outbreak-causing pest species. Outbreaks by one such species, the black oak gall wasp, Zapatella davisae Buffington & Melika (Hymenoptera: Cynipidae: Cynipini), have led to extensive damage and mortality of black oaks, Quercus Velutina L. (Fagales: Fagaceae), in the northeastern United States. Here we sequenced fragments of the nuclear ribosomal gene 28S, and the nuclear protein coding gene long-wavelength opsin from samples of Z. davisae collected on Cape Cod, MA, and Long Island, NY. Using these sequences and sequences previously published from the mitochondrial locus cytochrome b, we performed Bayesian and maximum likelihood multilocus phylogenetic reconstructions based on a concatenated alignment including species of gall wasps in the tribe Cynipini from which all three loci were present in the GenBank database. Confirming morphological work, we find that Z. davisae is most closely related to species in the genera Callirhytis and Neuroterus, and appears to be a basal member of the “Quercus” section of the tribe Cynipini. We find that recent generic reclassifications within the Cynipini have made great progress towards clarifying the taxonomic relationships of species of gall-inducing wasps in this tribe, and we comment on several classifications that require additional research.
-
development of microsatellite markers for an outbreaking species of oak gall wasp zapatella davisae hymenoptera cynipidae in the northeastern united states
Bulletin of Entomological Research, 2019Co-Authors: Jeremy C Andersen, Monica J. Davis, C P Camp, N P Havill, Joseph S. ElkintonAbstract:Populations of the recently described black oak gall wasp, Zapatella davisae Buffington (Hymenoptera: Cynipidae), have been identified as the cause of extensive tree damage and mortality to black oaks, Quercus Velutina Lamarck (Fagales: Fagaceae), in the northeastern United States. Relatively little is known, however, about the distribution, phylogenetic placement, and lifecycle of this important tree pest. Therefore, we conducted next-generation sequencing using the Ion Torrent™ PGM (ThermoFisher Scientific, Inc.) platform to develop genomic resources for the study of Z. davisae and for other closely related species of oak gall wasps. Individual sequence reads were aligned, assembled into unique contigs, and the contigs were then utilized for the in silico isolation and development of microsatellite markers. In total, we screened 36 candidate microsatellite loci, of which 23 amplified consistently (five polymorphic and 18 monomorphic). We then examined whether the polymorphic loci could be used to infer whether populations of Z. davisae from Cape Cod and Nantucket are sexual or asexual by calculating several metrics of genetic diversity that might indicate the mode of reproduction. These included testing for statistical deviations from Hardy–Weinberg equilibrium (HWE) and for linkage disequilibrium (LD), observations for the presence of the Meselson effect, and by calculating the probability that clonal individuals are more prevalent than would be expected in a randomly mating population. While we found significant deviations from HWE and more clonal individuals than expected, our estimates of the Meselson effect were inconclusive due to limited sampling, and we found no evidence of LD. Therefore, the sexual/asexual status of Z. davisae populations remains uncertain.
-
identification of the parasitoid community associated with an outbreaking gall wasp zapatella davisae and their relative abundances in new england and long island new york
Ecology and Evolution, 2019Co-Authors: Monica J. Davis, Jeremy C Andersen, Joseph S. ElkintonAbstract:Gall wasps (Hymenoptera: Cynipidae) are phytophagous insects that often go unnoticed; however, when they are introduced to a new area or released from their natural enemies, they have the capacity to outbreak and cause extensive foliar damage. One such outbreaking pest, Zapatella davisae (Cynipidae: Cynipini), causes significant damage and mortality to black oak, Quercus Velutina, in the northeastern United States. In this study, we aimed to identify the parasitoid community associated with Z. davisae, compare differences in percent parasitism of Z. davisae in Cape Cod and Long Island, and determine which parasitoid species contribute most to parasitism in each region. From both locations, we reared parasitoids, identified morphological groups, analyzed percent parasitism rates for each group, and used DNA barcoding to provide species-level identifications. On Long Island, there was nearly 100% parasitism in 2015 followed by a near total collapse of the population in 2016. In contrast, parasitism rates were lower and remained consistent on Cape Cod between 2015 and 2016, which may explain the greater canopy damage observed in that region. Species of Sycophila were the dominant parasitoids, with one species Sycophila nr. novascotiae representing ~65% of reared parasitoids from Long Island, and two species of Sycophila (S. nr. novascotiae and S. foliatae) with near equal representations on Cape Cod. In order to manage an insect pest, it is important to understand factors that influence its mortality and survival. An understanding of how these infestations progress overtime can help predict the impact that newer infestations in Nantucket, MA, and coastal Rhode Island will have on black oak populations and will aid in the management of this rapidly spreading gall wasp pest.
-
Efficacy of Two Systemic Insecticides With Stem Gall Wasp, Zapatella davisae (Hymenoptera: Cynipidae) on Black Oak.
Journal of economic entomology, 2018Co-Authors: Monica J. Davis, Joseph S. ElkintonAbstract:Black oak, Quercus Velutina Lamarck, is the dominant deciduous tree on Cape Cod, Nantucket, and Martha’s Vineyard, Massachusetts, and in recent years it has experienced widespread mortality and severe canopy loss due to infestations of a stem gall wasp, Zapatella davisae Buffington and Melika (Hymenoptera: Cynipidae). A single application of systemic insecticides emamectin benzoate and imidacloprid was found to reduce or prevent further accumulation of Z. davisae damage on infested black oak during a 1-yr trial.
-
the description of zapatella davisae new species hymenoptera cynipidae a pest gallwasp of black oak Quercus Velutina in new england usa
Proceedings of the Entomological Society of Washington, 2016Co-Authors: Matthew L Buffington, Monica J. Davis, George Melika, Joseph S. ElkintonAbstract:Abstract. Many species of gall wasp (Cynipidae) essentially co-exist with their host oak tree species. Occasionally, the association becomes destructive to the tree, as is the case with Zapatella davisae, new species. This species is a twig galler, and as such, in the cases of heavy infestation, cause flagging, leaf clumping, and dieback of branches and twigs. Historical records of other species of Zapatella suggest that members of this genus have a checkered record with respect to damaging their host plants in North America, and these data are summarized here.
Jeremy C Andersen - One of the best experts on this subject based on the ideXlab platform.
-
molecular placement of an outbreak causing gall wasp zapatella davisae hymenoptera cynipidae with comments on phylogenetic arrangements in the tribe cynipini
Journal of Entomological Science, 2021Co-Authors: Jeremy C Andersen, Monica J. Davis, Katherine N Schick, Joseph S. ElkintonAbstract:Gall wasps (Hymenoptera: Cynipidae) have fascinated researchers for centuries due to the elaborate diversity of charismatic galls they produce, the presence of unique reproductive systems (e.g., a form of cyclical parthenogenesis), the possible convergent evolution of semiparasitic gall wasp forms (i.e., “inquilines”), and their multitrophic interactions. While many classifications for gall wasps have been proposed, recent DNA sequence efforts combined with taxonomic revisions are beginning to clarify the evolutionary relationships of this group. To date, however, a well resolved phylogeny is lacking, complicating the study of outbreak-causing pest species. Outbreaks by one such species, the black oak gall wasp, Zapatella davisae Buffington & Melika (Hymenoptera: Cynipidae: Cynipini), have led to extensive damage and mortality of black oaks, Quercus Velutina L. (Fagales: Fagaceae), in the northeastern United States. Here we sequenced fragments of the nuclear ribosomal gene 28S, and the nuclear protein coding gene long-wavelength opsin from samples of Z. davisae collected on Cape Cod, MA, and Long Island, NY. Using these sequences and sequences previously published from the mitochondrial locus cytochrome b, we performed Bayesian and maximum likelihood multilocus phylogenetic reconstructions based on a concatenated alignment including species of gall wasps in the tribe Cynipini from which all three loci were present in the GenBank database. Confirming morphological work, we find that Z. davisae is most closely related to species in the genera Callirhytis and Neuroterus, and appears to be a basal member of the “Quercus” section of the tribe Cynipini. We find that recent generic reclassifications within the Cynipini have made great progress towards clarifying the taxonomic relationships of species of gall-inducing wasps in this tribe, and we comment on several classifications that require additional research.
-
rise and fall of an oak gall wasp hymenoptera cynipidae outbreak in massachusetts
Environmental Entomology, 2019Co-Authors: Cameron J Smithfreedman, Katherine N Schick, Jeremy C Andersen, Brian P Griffin, Joseph S. ElkintonAbstract:The recently described oak gall wasp Zapatella davisae Buffington & Melika (Hymenoptera: Cynipidae) has caused extensive damage and mortality to black oak trees, Quercus Velutina L. (Fagales: Fagaceae), in coastal parts of New England, United States. Like many newly described and/or newly introduced species, it is unclear how long populations of Z. davisae have existed in this region. However, as this species forms galls on the woody-tissue of its host, it may be possible to obtain historical information about changes in its population size by examining the presence of galls in relation to annual growth nodes. Here, we explore the utility of this approach to determine population size changes in Z. davisae densities on Nantucket, Martha's Vineyard, and Cape Cod, Massachusetts, through dissection of black oak branches. In addition, we calculated parasitism rates during the years of study and obtained morphological and molecular identifications for the parasitoids associated with Z. davisae. Our results show significant changes in population sizes, with higher levels of parasitism at sites on Martha's Vineyard and Cape Cod compared to sites on Nantucket. In addition, morphological examinations, in combination with DNA sequencing, identified the associated parasitoids as five species in the genus Sycophila Walker (Hymenoptera: Eurytomidae). We comment that considerable morphological variation within several of these recovered species was observed, present the first record of males for a species from which only females have been described, and suggest that future work is required to clarify the species boundaries for this important parasitoid group.
-
development of microsatellite markers for an outbreaking species of oak gall wasp zapatella davisae hymenoptera cynipidae in the northeastern united states
Bulletin of Entomological Research, 2019Co-Authors: Jeremy C Andersen, Monica J. Davis, C P Camp, N P Havill, Joseph S. ElkintonAbstract:Populations of the recently described black oak gall wasp, Zapatella davisae Buffington (Hymenoptera: Cynipidae), have been identified as the cause of extensive tree damage and mortality to black oaks, Quercus Velutina Lamarck (Fagales: Fagaceae), in the northeastern United States. Relatively little is known, however, about the distribution, phylogenetic placement, and lifecycle of this important tree pest. Therefore, we conducted next-generation sequencing using the Ion Torrent™ PGM (ThermoFisher Scientific, Inc.) platform to develop genomic resources for the study of Z. davisae and for other closely related species of oak gall wasps. Individual sequence reads were aligned, assembled into unique contigs, and the contigs were then utilized for the in silico isolation and development of microsatellite markers. In total, we screened 36 candidate microsatellite loci, of which 23 amplified consistently (five polymorphic and 18 monomorphic). We then examined whether the polymorphic loci could be used to infer whether populations of Z. davisae from Cape Cod and Nantucket are sexual or asexual by calculating several metrics of genetic diversity that might indicate the mode of reproduction. These included testing for statistical deviations from Hardy–Weinberg equilibrium (HWE) and for linkage disequilibrium (LD), observations for the presence of the Meselson effect, and by calculating the probability that clonal individuals are more prevalent than would be expected in a randomly mating population. While we found significant deviations from HWE and more clonal individuals than expected, our estimates of the Meselson effect were inconclusive due to limited sampling, and we found no evidence of LD. Therefore, the sexual/asexual status of Z. davisae populations remains uncertain.
-
identification of the parasitoid community associated with an outbreaking gall wasp zapatella davisae and their relative abundances in new england and long island new york
Ecology and Evolution, 2019Co-Authors: Monica J. Davis, Jeremy C Andersen, Joseph S. ElkintonAbstract:Gall wasps (Hymenoptera: Cynipidae) are phytophagous insects that often go unnoticed; however, when they are introduced to a new area or released from their natural enemies, they have the capacity to outbreak and cause extensive foliar damage. One such outbreaking pest, Zapatella davisae (Cynipidae: Cynipini), causes significant damage and mortality to black oak, Quercus Velutina, in the northeastern United States. In this study, we aimed to identify the parasitoid community associated with Z. davisae, compare differences in percent parasitism of Z. davisae in Cape Cod and Long Island, and determine which parasitoid species contribute most to parasitism in each region. From both locations, we reared parasitoids, identified morphological groups, analyzed percent parasitism rates for each group, and used DNA barcoding to provide species-level identifications. On Long Island, there was nearly 100% parasitism in 2015 followed by a near total collapse of the population in 2016. In contrast, parasitism rates were lower and remained consistent on Cape Cod between 2015 and 2016, which may explain the greater canopy damage observed in that region. Species of Sycophila were the dominant parasitoids, with one species Sycophila nr. novascotiae representing ~65% of reared parasitoids from Long Island, and two species of Sycophila (S. nr. novascotiae and S. foliatae) with near equal representations on Cape Cod. In order to manage an insect pest, it is important to understand factors that influence its mortality and survival. An understanding of how these infestations progress overtime can help predict the impact that newer infestations in Nantucket, MA, and coastal Rhode Island will have on black oak populations and will aid in the management of this rapidly spreading gall wasp pest.
Karina V R Schafer - One of the best experts on this subject based on the ideXlab platform.
-
Comparison of Tissue Heat Balance- and Thermal Dissipation-Derived Sap Flow Measurements in Ring-Porous Oaks and a Pine
Frontiers in Plant Science, 2012Co-Authors: Heidi J Renninger, Karina V R SchaferAbstract:Sap flow measurements have become integral in many physiological and ecological investigations. A number of methods are used to estimate sap flow rates in trees, but probably the most popular is the thermal dissipation (TD) method because of its affordability, relatively low power consumption, and ease of use. However, there have been questions about the use of this method in ring-porous species and whether individual species and site calibrations are needed. We made concurrent measurements of sap flow rates using TD sensors and the tissue heat balance (THB) method in two oak species (Quercus prinus Willd. and Quercus Velutina Lam.) and one pine (Pinus echinata Mill.). We also made concurrent measurements of sap flow rates using both 1 and 2-cm long TD sensors in both oak species. We found that both the TD and THB systems tended to match well in the pine individual, but sap flow rates were underestimated by 2-cm long TD sensors in five individuals of the two ring-porous oak species. Underestimations of 20-35% occurred in Q. prinus even when a "Clearwater" correction was applied to account for the shallowness of the sapwood depth relative to the sensor length and flow rates were underestimated by up to 50% in Q. Velutina. Two centimeter long TD sensors also underestimated flow rates compared with 1-cm long sensors in Q. prinus, but only at large flow rates. When 2-cm long sensor data in Q. prinus were scaled using the regression with 1-cm long data, daily flow rates matched well with the rates measured by the THB system. Daily plot level transpiration estimated using TD sap flow rates and scaled 1 cm sensor data averaged about 15% lower than those estimated by the THB method. Therefore, these results suggest that 1-cm long sensors are appropriate in species with shallow sapwood, however more corrections may be necessary in ring-porous species.
-
Comparison of heat balance- (Čermák) and heat dissipation- (Granier) derived sap flow measurements in ring-porous oaks and a pine species
Frontiers Media S.A., 2012Co-Authors: Heidi J Renninger, Karina V R SchaferAbstract:Sap flow measurements have become integral in many physiological and ecological investigations. A number of methods are used to estimate sap flow rates in trees, but probably the most popular is the heat dissipation method (Granier) because of its affordability, relatively low power consumption and ease of use. However, there have been questions about the use of this method in ring-porous species and whether individual species and site calibrations are needed. We made concurrent measurements of sap flow rates using heat dissipation sensors and the heat balance method (Čermák) in two oak species (Quercus prinus Willd. and Quercus Velutina Lam.) and one pine species (Pinus echinata Mill.). We also made concurrent measurements of sap flow rates using both 1-cm long and 2-cm long Granier-style heat dissipation sensors in both oak species. We found that both the heat dissipation and heat balance systems tended to match well in the pine individual, but sap flow rates were underestimated by 2-cm long heat dissipation sensors in five individuals of the two ring-porous oak species. Underestimations of 20-35% occurred in Q. prinus even when a Clearwater correction was applied to account for the shallowness of the sapwood depth relative to the sensor length and flow rates were underestimated by up to 50% in Q. Velutina. Two-cm long heat dissipation sensors also underestimated flow rates compared with 1-cm long sensors in Q. prinus, but only at large flow rates. When 2-cm long sensor data in Q. prinus were scaled using the regression with 1-cm long data, daily flow rates matched well with the rates measured by the heat balance system. Daily plot-level transpiration estimated using heat dissipation sap flow rates was about 15% lower than those estimated by the heat balance method at the highest flow rates. Therefore, these results suggest that 1-cm long sensors are appropriate in species with shallow sapwood, however more corrections may be necessary in ring-porous species
Heidi J Renninger - One of the best experts on this subject based on the ideXlab platform.
-
Comparison of Tissue Heat Balance- and Thermal Dissipation-Derived Sap Flow Measurements in Ring-Porous Oaks and a Pine
Frontiers in Plant Science, 2012Co-Authors: Heidi J Renninger, Karina V R SchaferAbstract:Sap flow measurements have become integral in many physiological and ecological investigations. A number of methods are used to estimate sap flow rates in trees, but probably the most popular is the thermal dissipation (TD) method because of its affordability, relatively low power consumption, and ease of use. However, there have been questions about the use of this method in ring-porous species and whether individual species and site calibrations are needed. We made concurrent measurements of sap flow rates using TD sensors and the tissue heat balance (THB) method in two oak species (Quercus prinus Willd. and Quercus Velutina Lam.) and one pine (Pinus echinata Mill.). We also made concurrent measurements of sap flow rates using both 1 and 2-cm long TD sensors in both oak species. We found that both the TD and THB systems tended to match well in the pine individual, but sap flow rates were underestimated by 2-cm long TD sensors in five individuals of the two ring-porous oak species. Underestimations of 20-35% occurred in Q. prinus even when a "Clearwater" correction was applied to account for the shallowness of the sapwood depth relative to the sensor length and flow rates were underestimated by up to 50% in Q. Velutina. Two centimeter long TD sensors also underestimated flow rates compared with 1-cm long sensors in Q. prinus, but only at large flow rates. When 2-cm long sensor data in Q. prinus were scaled using the regression with 1-cm long data, daily flow rates matched well with the rates measured by the THB system. Daily plot level transpiration estimated using TD sap flow rates and scaled 1 cm sensor data averaged about 15% lower than those estimated by the THB method. Therefore, these results suggest that 1-cm long sensors are appropriate in species with shallow sapwood, however more corrections may be necessary in ring-porous species.
-
Comparison of heat balance- (Čermák) and heat dissipation- (Granier) derived sap flow measurements in ring-porous oaks and a pine species
Frontiers Media S.A., 2012Co-Authors: Heidi J Renninger, Karina V R SchaferAbstract:Sap flow measurements have become integral in many physiological and ecological investigations. A number of methods are used to estimate sap flow rates in trees, but probably the most popular is the heat dissipation method (Granier) because of its affordability, relatively low power consumption and ease of use. However, there have been questions about the use of this method in ring-porous species and whether individual species and site calibrations are needed. We made concurrent measurements of sap flow rates using heat dissipation sensors and the heat balance method (Čermák) in two oak species (Quercus prinus Willd. and Quercus Velutina Lam.) and one pine species (Pinus echinata Mill.). We also made concurrent measurements of sap flow rates using both 1-cm long and 2-cm long Granier-style heat dissipation sensors in both oak species. We found that both the heat dissipation and heat balance systems tended to match well in the pine individual, but sap flow rates were underestimated by 2-cm long heat dissipation sensors in five individuals of the two ring-porous oak species. Underestimations of 20-35% occurred in Q. prinus even when a Clearwater correction was applied to account for the shallowness of the sapwood depth relative to the sensor length and flow rates were underestimated by up to 50% in Q. Velutina. Two-cm long heat dissipation sensors also underestimated flow rates compared with 1-cm long sensors in Q. prinus, but only at large flow rates. When 2-cm long sensor data in Q. prinus were scaled using the regression with 1-cm long data, daily flow rates matched well with the rates measured by the heat balance system. Daily plot-level transpiration estimated using heat dissipation sap flow rates was about 15% lower than those estimated by the heat balance method at the highest flow rates. Therefore, these results suggest that 1-cm long sensors are appropriate in species with shallow sapwood, however more corrections may be necessary in ring-porous species
