In this investigation work, FA （fatty acids） components produced by Oak tree fruits were determined as a fat content in acorn, pericarp and cupules in the three Oak species （Q. aegilops subsp brantii, Q. libani and...In this investigation work, FA （fatty acids） components produced by Oak tree fruits were determined as a fat content in acorn, pericarp and cupules in the three Oak species （Q. aegilops subsp brantii, Q. libani and Q. infectoria）. The plant samples were collected in Khamza Mountain Oak forest of Sulaimani/Kurdistan Region during October 2008. Exposed to air room temperature for drying and ground to fine powder by electric blender then stored in a plastic containers at 4 ℃. In the preliminary step, fat detected from acorn, pericarp and cuplules by ＂Soxhlet＂ method and the various FA （saturated＆unsaturated） were separated and determined by GLC （gas liquid chromatography）. The amount of saturated FA in the acorn of the Q. aegilops subsp brantii, Q. libani and Q. infectoria were more than 25%, 7% and 18% while in the pericarp were more than 9%, 12% and 11%, but in the cuplules were more than 9%, 10% and 10%, respectively. The amount of unsaturated FA in the acorn of the Q. aegilops subsp brantii, Q. libani and Q. infectoria were more than 70%, 91% and 79% while in the pericarp were more than 87%, 84% and 81%, but in the cuplules were more than 87%, 88% and 84%, respectively. The most abundant FA found in the acorn, pericarp and cuplules were Oleic followed by Lenoleic, except the cuplules of Q. infectoria, the most abundant FA was Lenoleic followed by Oleic.展开更多
This study was conducted to determine primary metabolites （protein, fat and total carbohydrate） and energy in various parts of Oak fruit （cotyledon, pericarp and cupules） for each of Quercus aegilops Subsp. branti...This study was conducted to determine primary metabolites （protein, fat and total carbohydrate） and energy in various parts of Oak fruit （cotyledon, pericarp and cupules） for each of Quercus aegilops Subsp. brantii, Quercus infectoria and Quercus libani. Oak fruits were collected during October in 2008 from three different native species of Quercus spp. in Khamza Mountain oak forest in Sulaimani city of Iraqi Kurdistan. The fruit samples were dried for moisture by oven and ash by Muffle Furnace. Samples were also analyzed for protein by Kjeldahl, fat by Soxhlet, total carbohydrate and energy by calculation （Atwater system）. This study revealed significant and high significant differences （P _〈 0.05 and P 〈 0.01） by using Duncan＇ s multiple range as a test of comparisons between means of studied species for various parts of oak fruits in content of energy and food compounds for each part of oak fruit. The energy content for cotyledon was 404.826-410.558 kcal/100g DM; pericarp, 397.618-406.850 kcal/100g DM and cupules, 387.100-391.109 kcal/100g DM; the maximum value for energy content was found in cotyledon of Q. infectoria. Protein content in cotyledon was 3.406-5.426% DM; pericarp, 2.542-2.609% DM and cupules, 1.272-2.066% DM, that cotyledon ofQ. aegilops Subsp. brantii contain highest amount of protein. Fat content in cotyledon was 3.375-3.942% DM; pericarp, 1.754-2.766% DM and cupules, 1.464-2.165% DM, maximum content of fat was found in cotyledon of Q. infectoria. Total Carbohydrate content in cotyledon was 88.491-90.364% DM; pericarp, 92.486-92.947% DM and cupules, 90.594-92.977% DM, the cupules of Q. infectoria contained highest content of total Carbohydrate.展开更多
Background:Nutrient resorption is critical for plants toward balancing their nutritional requirements and adapting to environmental variabilities,which further impacts litter quality and nutrient cycling.However,the i...Background:Nutrient resorption is critical for plants toward balancing their nutritional requirements and adapting to environmental variabilities,which further impacts litter quality and nutrient cycling.However,the interannual variability of nutrient resorption under climate change remains unclear.Methods:We investigated the five-year nutrient resorption efficiencies(NuRE,%)of 14 elements in three deciduous oak tree species(Quercus aliena var.acuteserrata,Q.glandulifera,and Q.variabilis)in a warm-temperate forest of Central China and assessed their relationships with interannual climate and soil factors.Results:Nutrient resorption did not differ between species but varied significantly between different years.For each year,N,P,S,K,C,Mg,and Zn were preferentially resorbed in all of the oak species in contrast to Ca,Na,Mn,Ba,Al,Fe,Cu,which were to some extent discriminated.Among the 14 elements,the NuRE of C,N,P,S,Ca,and Mg was more sensitive to interannual climate variations in the three oak species.The carbon resorption efficiency was significantly increased during the driest year of the study(2014);N resorption efficiency was reduced with temperature;whereas N and P resorption efficiency initially decreased and then increased with precipitation.Moreover,the elements with higher NuREs typically had lower coefficient of variation(CV)in all three oak species.Conclusions:Different oak species exhibited analogous nutrient conservation strategies in response to annual climate variabilities,and interannual climate variations strongly impacted plant nutrient resorption.Deciduous plants may establish a tradeoff mechanism to rebalance somatic nutrients for regrowth at the end of the growing season.展开更多
Scatter hoarding by corvids （crows, jays, magpies, and nutcrackers） provides seed dispersal for many large-seeded plants, including oaks and pines. When hoarding seeds, corvids often choose nonrandom locations throu...Scatter hoarding by corvids （crows, jays, magpies, and nutcrackers） provides seed dispersal for many large-seeded plants, including oaks and pines. When hoarding seeds, corvids often choose nonrandom locations throughout the landscape, resulting in differential survival of seeds. In the context of habitat restoration, such disproportional storing of seeds in areas suitable for germin- ation and establishment can accelerate expansion and recovery of large-seeded tree populations and their associated ecosystems. Here, we investigate the spatial preferences of island scrub jays Aphelocoma insularis during scatter hoarding of acorns （Quercus spp.） on Santa Cruz Island. We use a large behavioral data set on the birds＇ behavior in combination with seedling surveys and spatial analysis to determine whether 1） island scrub jays disproportionally cache seeds in specific habitat types, and 2） whether the preferred habitat type is suitable for oak regeneration. Our results show that the jays nonrandomly cache acorns across the landscape; they use chaparral and coastal sage scrub disproportionally while avoiding open and grassy areas. The areas used most often for caching were also the areas with the highest oak seedling densities. We discuss the potential role of these findings for the recovery of Santa Cruz Island＇s oak habitat since the 1980s.展开更多
Synchrony between seed growth and oogenesis is suggested to largely shape trophic breadth of seed-feeding insects and ultimately to contribute to their co-existence by means of resource partitioning or in the time whe...Synchrony between seed growth and oogenesis is suggested to largely shape trophic breadth of seed-feeding insects and ultimately to contribute to their co-existence by means of resource partitioning or in the time when infestation occurs.Here we investigated:(i)the role of seed phenology and sexual maturation of females in the host specificity of seed-feeding weevils(Curculio spp.)predating in hazel and oak mixed forests;and(ii)the consequences that trophic breadth and host distribution have in the genetic structure of the weevil populations.DNA analyses were used to establish unequivocally host specificity and to determine the population genetic structure.We identified 4 species with different specificity,namely Curculio nucum females matured earlier and infested a unique host(hazelnuts,Corylus avellana)while 3 species(Curculio venosus,Curculio glandium and Curculio elephas)predated upon the acorns of the 2 oaks(Quercus ilex and Quercus pubescens).The high specificity of C.nucum coupled with a more discontinuous distribution of hazel trees resulted in a significant genetic structure among sites.In addition,the presence of an excess of local rare haplotypes indicated that C.nucum populations went through genetic expansion after recent bottlenecks.Conversely,these effects were not observed in the more generalist Curculio glandium predating upon oaks.Ultimately,co-existence of weevil species in this multi-host-parasite system is influenced by both resource and time partitioning.To what extent the restriction in gene flow among C.nucum populations may have negative consequences for their persistence in a time of increasing disturbances(e.g.drought in Mediterranean areas)deserves further research.展开更多
文摘In this investigation work, FA （fatty acids） components produced by Oak tree fruits were determined as a fat content in acorn, pericarp and cupules in the three Oak species （Q. aegilops subsp brantii, Q. libani and Q. infectoria）. The plant samples were collected in Khamza Mountain Oak forest of Sulaimani/Kurdistan Region during October 2008. Exposed to air room temperature for drying and ground to fine powder by electric blender then stored in a plastic containers at 4 ℃. In the preliminary step, fat detected from acorn, pericarp and cuplules by ＂Soxhlet＂ method and the various FA （saturated＆unsaturated） were separated and determined by GLC （gas liquid chromatography）. The amount of saturated FA in the acorn of the Q. aegilops subsp brantii, Q. libani and Q. infectoria were more than 25%, 7% and 18% while in the pericarp were more than 9%, 12% and 11%, but in the cuplules were more than 9%, 10% and 10%, respectively. The amount of unsaturated FA in the acorn of the Q. aegilops subsp brantii, Q. libani and Q. infectoria were more than 70%, 91% and 79% while in the pericarp were more than 87%, 84% and 81%, but in the cuplules were more than 87%, 88% and 84%, respectively. The most abundant FA found in the acorn, pericarp and cuplules were Oleic followed by Lenoleic, except the cuplules of Q. infectoria, the most abundant FA was Lenoleic followed by Oleic.
文摘This study was conducted to determine primary metabolites （protein, fat and total carbohydrate） and energy in various parts of Oak fruit （cotyledon, pericarp and cupules） for each of Quercus aegilops Subsp. brantii, Quercus infectoria and Quercus libani. Oak fruits were collected during October in 2008 from three different native species of Quercus spp. in Khamza Mountain oak forest in Sulaimani city of Iraqi Kurdistan. The fruit samples were dried for moisture by oven and ash by Muffle Furnace. Samples were also analyzed for protein by Kjeldahl, fat by Soxhlet, total carbohydrate and energy by calculation （Atwater system）. This study revealed significant and high significant differences （P _〈 0.05 and P 〈 0.01） by using Duncan＇ s multiple range as a test of comparisons between means of studied species for various parts of oak fruits in content of energy and food compounds for each part of oak fruit. The energy content for cotyledon was 404.826-410.558 kcal/100g DM; pericarp, 397.618-406.850 kcal/100g DM and cupules, 387.100-391.109 kcal/100g DM; the maximum value for energy content was found in cotyledon of Q. infectoria. Protein content in cotyledon was 3.406-5.426% DM; pericarp, 2.542-2.609% DM and cupules, 1.272-2.066% DM, that cotyledon ofQ. aegilops Subsp. brantii contain highest amount of protein. Fat content in cotyledon was 3.375-3.942% DM; pericarp, 1.754-2.766% DM and cupules, 1.464-2.165% DM, maximum content of fat was found in cotyledon of Q. infectoria. Total Carbohydrate content in cotyledon was 88.491-90.364% DM; pericarp, 92.486-92.947% DM and cupules, 90.594-92.977% DM, the cupules of Q. infectoria contained highest content of total Carbohydrate.
基金supported by the National Key Technology Research and Development Program of China(2017YFC0505501,2016YFD0600206,and 2013BAD11B01)the National Natural Science Foundation of China(NSFC 31270640 and 31770746)the China Postdoctoral Science Foundation(20Z102060010).
文摘Background:Nutrient resorption is critical for plants toward balancing their nutritional requirements and adapting to environmental variabilities,which further impacts litter quality and nutrient cycling.However,the interannual variability of nutrient resorption under climate change remains unclear.Methods:We investigated the five-year nutrient resorption efficiencies(NuRE,%)of 14 elements in three deciduous oak tree species(Quercus aliena var.acuteserrata,Q.glandulifera,and Q.variabilis)in a warm-temperate forest of Central China and assessed their relationships with interannual climate and soil factors.Results:Nutrient resorption did not differ between species but varied significantly between different years.For each year,N,P,S,K,C,Mg,and Zn were preferentially resorbed in all of the oak species in contrast to Ca,Na,Mn,Ba,Al,Fe,Cu,which were to some extent discriminated.Among the 14 elements,the NuRE of C,N,P,S,Ca,and Mg was more sensitive to interannual climate variations in the three oak species.The carbon resorption efficiency was significantly increased during the driest year of the study(2014);N resorption efficiency was reduced with temperature;whereas N and P resorption efficiency initially decreased and then increased with precipitation.Moreover,the elements with higher NuREs typically had lower coefficient of variation(CV)in all three oak species.Conclusions:Different oak species exhibited analogous nutrient conservation strategies in response to annual climate variabilities,and interannual climate variations strongly impacted plant nutrient resorption.Deciduous plants may establish a tradeoff mechanism to rebalance somatic nutrients for regrowth at the end of the growing season.
文摘Scatter hoarding by corvids （crows, jays, magpies, and nutcrackers） provides seed dispersal for many large-seeded plants, including oaks and pines. When hoarding seeds, corvids often choose nonrandom locations throughout the landscape, resulting in differential survival of seeds. In the context of habitat restoration, such disproportional storing of seeds in areas suitable for germin- ation and establishment can accelerate expansion and recovery of large-seeded tree populations and their associated ecosystems. Here, we investigate the spatial preferences of island scrub jays Aphelocoma insularis during scatter hoarding of acorns （Quercus spp.） on Santa Cruz Island. We use a large behavioral data set on the birds＇ behavior in combination with seedling surveys and spatial analysis to determine whether 1） island scrub jays disproportionally cache seeds in specific habitat types, and 2） whether the preferred habitat type is suitable for oak regeneration. Our results show that the jays nonrandomly cache acorns across the landscape; they use chaparral and coastal sage scrub disproportionally while avoiding open and grassy areas. The areas used most often for caching were also the areas with the highest oak seedling densities. We discuss the potential role of these findings for the recovery of Santa Cruz Island＇s oak habitat since the 1980s.
基金This research was supported by the projects FORASSEMBLY(CGL2015-70558-P)and PLAGANADO(AGL2014-54739-R)of the Spanish Ministry of Economythe projects BEEMED(SGR913)(Generalitat de Catalunya)and PII1C09-0256-9052(Regional Government of Castilla-La Mancha and the European Social Fund)R.B.was funded by a contract of the Program Atracción de Talento Investigador(Gobierno de Extremadura).
文摘Synchrony between seed growth and oogenesis is suggested to largely shape trophic breadth of seed-feeding insects and ultimately to contribute to their co-existence by means of resource partitioning or in the time when infestation occurs.Here we investigated:(i)the role of seed phenology and sexual maturation of females in the host specificity of seed-feeding weevils(Curculio spp.)predating in hazel and oak mixed forests;and(ii)the consequences that trophic breadth and host distribution have in the genetic structure of the weevil populations.DNA analyses were used to establish unequivocally host specificity and to determine the population genetic structure.We identified 4 species with different specificity,namely Curculio nucum females matured earlier and infested a unique host(hazelnuts,Corylus avellana)while 3 species(Curculio venosus,Curculio glandium and Curculio elephas)predated upon the acorns of the 2 oaks(Quercus ilex and Quercus pubescens).The high specificity of C.nucum coupled with a more discontinuous distribution of hazel trees resulted in a significant genetic structure among sites.In addition,the presence of an excess of local rare haplotypes indicated that C.nucum populations went through genetic expansion after recent bottlenecks.Conversely,these effects were not observed in the more generalist Curculio glandium predating upon oaks.Ultimately,co-existence of weevil species in this multi-host-parasite system is influenced by both resource and time partitioning.To what extent the restriction in gene flow among C.nucum populations may have negative consequences for their persistence in a time of increasing disturbances(e.g.drought in Mediterranean areas)deserves further research.
