High rainfall in subtropical regions can leach cation elements from ecosystems,which may limit plant growth.Plants often develop efficient resorption patterns to recycle elements,but there is relatively little availab...High rainfall in subtropical regions can leach cation elements from ecosystems,which may limit plant growth.Plants often develop efficient resorption patterns to recycle elements,but there is relatively little available information on this topic.In February 2012,a common garden was established in a subtropical forest by planting dominant trees from the area.Green and senescent leaves were sampled from 11 tree species.The concentrations of potassium(K),calcium(Ca),sodium(Na)and magnesium(Mg)were determined,and the resorption efficiencies were calculated.The results showed significant K,Na and Mg resorption in most of the investigated tree species,while Ca mainly displayed accumulation.Evergreen coniferous and evergreen broad-leaved trees(such as Cunninghamia lanceolata,Pinus massoniana,Cinnamomum camphora,and Michelia macclurei)exhibited relatively higher resorption efficiencies of K(39.0%-87.5%)and Na(18.3%-50.2%)than deciduous broad-leaved trees.Higher Mg resorption efficiencies(>50%)were detected in Liriodendron chinense,C.lanceolata and P.massoniana than in other trees.Overall,evergreen coniferous and evergreen broad-leaved trees could show higher cation resorption than deciduous broad-leaved trees.K and Mg resorption efficiencies and Ca accumulation decrease with increasing nutrient concentrations in green leaves.Our results emphasize that nutrient resorption patterns largely depend on elements and plant functions,which provides new insights into the nutrient use strategies of subtropical plants and a reference for the selection of suitable tree species in this region.展开更多
Knowing what native trees can recr uit on degraded areas allows selecting the best species to restore these sites.However,as this information is not often available,experimentation is required before large-scale plant...Knowing what native trees can recr uit on degraded areas allows selecting the best species to restore these sites.However,as this information is not often available,experimentation is required before large-scale planting.This study used ex situ experiments to make these decisions on recruitment.Competition with r-strategist plants,excessive solar radiation and water shortage commonly impair tree recruitment in open habitats.The experiments focused on the interactions among these factors and were conducted with three pioneer species from seasonally dry forests of northwest Argentina,Anadenanthera colubrina,Ceiba chodatii and Jacaranda mimosifolia.Seeds of each species were sown at two light levels(sunlight/shade),two rainfall levels(full/reduced)and two levels of interspecific competition(with/without competitor)in a tree nursery.Seedling emergence and survival were monitored over a year and the results indicate that species differentially respond to varying levels of light and water.Seedlings of A.colubrina tolerated water shortages under elevated solar radiation,which are desirable features for forest restoration.Seedlings of C.chodatii tolerated shade and drought,suggesting that they require shading for establishing in open areas.However,J.mimosifolia seedlings neither tolerated full sunlight nor water shortages,suggesting that this species requires shading and regular watering if used in reforestation.Regardless of the effects of light and water,the survival of all species was reduced by interspecific competition.These results highlight the importance of experimentation for selecting the best species for forest restoration and can enhance the cost/benefit ratios of these actions.展开更多
基金The study was supported by grants from National Natural Science Foundation of China(Grants 31800521,31800373 and 31922052).Datasets for this research are included in this paper。
文摘High rainfall in subtropical regions can leach cation elements from ecosystems,which may limit plant growth.Plants often develop efficient resorption patterns to recycle elements,but there is relatively little available information on this topic.In February 2012,a common garden was established in a subtropical forest by planting dominant trees from the area.Green and senescent leaves were sampled from 11 tree species.The concentrations of potassium(K),calcium(Ca),sodium(Na)and magnesium(Mg)were determined,and the resorption efficiencies were calculated.The results showed significant K,Na and Mg resorption in most of the investigated tree species,while Ca mainly displayed accumulation.Evergreen coniferous and evergreen broad-leaved trees(such as Cunninghamia lanceolata,Pinus massoniana,Cinnamomum camphora,and Michelia macclurei)exhibited relatively higher resorption efficiencies of K(39.0%-87.5%)and Na(18.3%-50.2%)than deciduous broad-leaved trees.Higher Mg resorption efficiencies(>50%)were detected in Liriodendron chinense,C.lanceolata and P.massoniana than in other trees.Overall,evergreen coniferous and evergreen broad-leaved trees could show higher cation resorption than deciduous broad-leaved trees.K and Mg resorption efficiencies and Ca accumulation decrease with increasing nutrient concentrations in green leaves.Our results emphasize that nutrient resorption patterns largely depend on elements and plant functions,which provides new insights into the nutrient use strategies of subtropical plants and a reference for the selection of suitable tree species in this region.
基金founded by The RuffordFires in mountain dry forests:importance of plant-plant interaction in the post-fire regeneration。
文摘Knowing what native trees can recr uit on degraded areas allows selecting the best species to restore these sites.However,as this information is not often available,experimentation is required before large-scale planting.This study used ex situ experiments to make these decisions on recruitment.Competition with r-strategist plants,excessive solar radiation and water shortage commonly impair tree recruitment in open habitats.The experiments focused on the interactions among these factors and were conducted with three pioneer species from seasonally dry forests of northwest Argentina,Anadenanthera colubrina,Ceiba chodatii and Jacaranda mimosifolia.Seeds of each species were sown at two light levels(sunlight/shade),two rainfall levels(full/reduced)and two levels of interspecific competition(with/without competitor)in a tree nursery.Seedling emergence and survival were monitored over a year and the results indicate that species differentially respond to varying levels of light and water.Seedlings of A.colubrina tolerated water shortages under elevated solar radiation,which are desirable features for forest restoration.Seedlings of C.chodatii tolerated shade and drought,suggesting that they require shading for establishing in open areas.However,J.mimosifolia seedlings neither tolerated full sunlight nor water shortages,suggesting that this species requires shading and regular watering if used in reforestation.Regardless of the effects of light and water,the survival of all species was reduced by interspecific competition.These results highlight the importance of experimentation for selecting the best species for forest restoration and can enhance the cost/benefit ratios of these actions.
