Highland barley is an important staple food in the Tibet,and the Tibetan Plateau is experiencing obvious climatic warming.However,few studies have examined the warming effects on highland barley growth and biomass all...Highland barley is an important staple food in the Tibet,and the Tibetan Plateau is experiencing obvious climatic warming.However,few studies have examined the warming effects on highland barley growth and biomass allocation under conditions of controlled experimental warming.This limits our ability to predict how highland barley will change as the climate changes in the future.An experiment of field warming at two magnitudes was performed in a highland barley system of the Tibet beginning in late May,2014.Infrared heaters were used to increase soil temperature.At the end of the warming experiment（September 14,2014）,plant growth parameters（plant height,basal diameter,shoot length and leaf number）,biomass accumulation parameters（total biomass,root biomass,stem biomass,leaf biomass and spike biomass）,and carbon and nitrogen concentration parameters（carbon concentration,nitrogen concentration,the ratio of carbon to nitrogen concentration in root,stem,leaf and spike）were sampled.The low-and high-level experimental warming significantly increased soil perimental warming did not significantly change.The low-and high-level experimental warming did not significantly affect plant growth parameters,biomass accumulation parameters,and carbon and nitrogen concentration parameters.There were also no significant differences of plant growth parameters,biomass accumulation parameters,and carbon and nitrogen concentration parameters between the low-and high-level experimental warming.Our findings suggest that the response of highland barley growth,total and component biomass accumulation,and carbon and nitrogen concentration to warming did not linearly change with warming magnitude in the Tibet.展开更多
In order to understand whether or not the response of vegetation indices and biomass production to warming varies with warming magnitude,an experiment of field warming at two magnitudes was conducted in an alpine mead...In order to understand whether or not the response of vegetation indices and biomass production to warming varies with warming magnitude,an experiment of field warming at two magnitudes was conducted in an alpine meadow on the northern Tibetan Plateau beginning in late June,2013.The normalized difference vegetation index（NDVI）,green normalized difference vegetation index（GNDVI） and soil adjusted vegetation index（SAVI） data were obtained using a Tetracam Agricultural Digital Camera in 2013–2014.The gross primary production（GPP） and aboveground plant biomass（AGB） were modeled using the surface measured NDVI and climatic data during the growing seasons（i.e.June–September） in 2013–2014.Both low and high warming significantly increased air temperature by 1.54 and 4.00°C,respectively,and significantly increased vapor pressure deficit by 0.13 and 0.31 kP a,respectively,in 2013-2014.There were no significant differences of GNDVI,AGB and ANPP among the three warming treatments.The high warming significantly reduced average NDVI by 23.3%（-0.06）,while the low warming did not affect average NDVI.The low and high warming significantly decreased average SAVI by 19.0%（-0.04） and 27.4%（-0.05）,respectively,and average GPP by 24.2%（i.e.0.21 g C m^（-2） d^（-1）） and 44.0%（i.e.0.39 g C m^（–2） d^（-1））,respectively.However,the differences of the average NDVI,SAVI,and GPP between low and high warming were negligible.Our findings suggest that a greater drying may dampen the effect of a higher warming on vegetation indices and biomass production in alpine meadow on the northern Tibetan Plateau.展开更多
No studies have examined the effect of experimental warming on the microbial biomass and community composition of soil in agricultural ecosystem on the Qinghai-Tibet Plateau. Thus it is unclear whether the influences ...No studies have examined the effect of experimental warming on the microbial biomass and community composition of soil in agricultural ecosystem on the Qinghai-Tibet Plateau. Thus it is unclear whether the influences of experimental warming on microbial communities in soil are related to warming magnitude in croplands on this Plateau. This study performed warming experiment(control, low-and high-level) in a highland barley system of the Lhasa River in May 2014 to examine the correlation between the response of microbial communities in soil to warming and warming magnitude. Topsoil samples(0–10 and 10–20 cm) were collected on September 14, 2014. Experimental warming at both low and high levels significantly increased soil temperature by 1.02 ℃ and 1.59 ℃, respectively at the depth of 15 cm. Phospho lipid fatty acid(PLFA) method was used to determine the microbial community in soil. The low-level experimental warming did not significantly affect the soil’s total PLFA, fungi, bacteria, arbuscular mycorrhizal fungi(AMF), actinomycetes, gram-positive bacteria(G+), gram-negative bacteria(G–), protozoa, the ratio of fungi to bacteria(F/B ratio), and ratio of G+ to G–(G+/G– ratio) at the 0–10 and 10–20 cm depth. The low-level experimental warming also did not significantly alter the composition of microbial community in soil at the 0–10 and 10–20 cm depth. The high-level experimental warming significantly increased total PLFA by 74.4%, fungi by 78.0%, bacteria by 74.0%, AMF by 66.9%, actinomycetes by 81.4%, G+ by 67.0% and G– by 74.4% at the 0–10 cm depth rather than at 10–20 cm depth. The high-level experimental warming significantly altered microbial community composition in soil at the 0–10 cm depth rather than at 10-20 cm depth. Our findings suggest that the response of microbial communities in soil to warming varied with warming magnitudes in the highland barley system of the Lhasa River.展开更多
基金The National Natural Science Foundation of China(31370458,41171084)the Youth Innovation Research Team Project of Key Laboratory of Ecosystem Network Observation and Modeling(LENOM2016Q0002)+3 种基金the Science and Technology Service Network Plan of Chinese Academy of Science(KFJ-EW-STS-070)the Science and Technology Plan Projects of Tibet Autonomous Region(Forage Grass Industry)the National Key Research and Development Plan of China(2016YFC05020052016YFC0502006)
文摘Highland barley is an important staple food in the Tibet,and the Tibetan Plateau is experiencing obvious climatic warming.However,few studies have examined the warming effects on highland barley growth and biomass allocation under conditions of controlled experimental warming.This limits our ability to predict how highland barley will change as the climate changes in the future.An experiment of field warming at two magnitudes was performed in a highland barley system of the Tibet beginning in late May,2014.Infrared heaters were used to increase soil temperature.At the end of the warming experiment（September 14,2014）,plant growth parameters（plant height,basal diameter,shoot length and leaf number）,biomass accumulation parameters（total biomass,root biomass,stem biomass,leaf biomass and spike biomass）,and carbon and nitrogen concentration parameters（carbon concentration,nitrogen concentration,the ratio of carbon to nitrogen concentration in root,stem,leaf and spike）were sampled.The low-and high-level experimental warming significantly increased soil perimental warming did not significantly change.The low-and high-level experimental warming did not significantly affect plant growth parameters,biomass accumulation parameters,and carbon and nitrogen concentration parameters.There were also no significant differences of plant growth parameters,biomass accumulation parameters,and carbon and nitrogen concentration parameters between the low-and high-level experimental warming.Our findings suggest that the response of highland barley growth,total and component biomass accumulation,and carbon and nitrogen concentration to warming did not linearly change with warming magnitude in the Tibet.
基金National Natural Science Foundation of China(31600432)National Key Research Projects of China(2016YFC0502005+3 种基金2016YFC0502006)Chinese Academy of Science Western Light Talents Program(Response of livestock carrying capability to climatic change and grazing in the alpine meadow of Northern Tibetan Plateau)the Science and Technology Plan Projects of Tibet Autonomous Region(Forage Grass Industry)the National Science and Technology Plan Project of China(2013BAC04B01,2011BAC09B03,2007BAC06B01)
文摘In order to understand whether or not the response of vegetation indices and biomass production to warming varies with warming magnitude,an experiment of field warming at two magnitudes was conducted in an alpine meadow on the northern Tibetan Plateau beginning in late June,2013.The normalized difference vegetation index（NDVI）,green normalized difference vegetation index（GNDVI） and soil adjusted vegetation index（SAVI） data were obtained using a Tetracam Agricultural Digital Camera in 2013–2014.The gross primary production（GPP） and aboveground plant biomass（AGB） were modeled using the surface measured NDVI and climatic data during the growing seasons（i.e.June–September） in 2013–2014.Both low and high warming significantly increased air temperature by 1.54 and 4.00°C,respectively,and significantly increased vapor pressure deficit by 0.13 and 0.31 kP a,respectively,in 2013-2014.There were no significant differences of GNDVI,AGB and ANPP among the three warming treatments.The high warming significantly reduced average NDVI by 23.3%（-0.06）,while the low warming did not affect average NDVI.The low and high warming significantly decreased average SAVI by 19.0%（-0.04） and 27.4%（-0.05）,respectively,and average GPP by 24.2%（i.e.0.21 g C m^（-2） d^（-1）） and 44.0%（i.e.0.39 g C m^（–2） d^（-1））,respectively.However,the differences of the average NDVI,SAVI,and GPP between low and high warming were negligible.Our findings suggest that a greater drying may dampen the effect of a higher warming on vegetation indices and biomass production in alpine meadow on the northern Tibetan Plateau.
基金National Natural Science Foundation of China(31370458,31600432,41807331)Bingwei Outstanding Young Talents Program of Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences(2018RC202)+2 种基金National Key Research Projects of China(2016YFC0502005,2016YFC0502006,2017YFA0604801)Youth Innovation Research Team Project of Key Laboratory of Ecosystem Network Observation and Modeling(LENOM2016Q0002)Tibet Science and Technology Major Projects of Pratacultural Industry(XZ201801NA02)
文摘No studies have examined the effect of experimental warming on the microbial biomass and community composition of soil in agricultural ecosystem on the Qinghai-Tibet Plateau. Thus it is unclear whether the influences of experimental warming on microbial communities in soil are related to warming magnitude in croplands on this Plateau. This study performed warming experiment(control, low-and high-level) in a highland barley system of the Lhasa River in May 2014 to examine the correlation between the response of microbial communities in soil to warming and warming magnitude. Topsoil samples(0–10 and 10–20 cm) were collected on September 14, 2014. Experimental warming at both low and high levels significantly increased soil temperature by 1.02 ℃ and 1.59 ℃, respectively at the depth of 15 cm. Phospho lipid fatty acid(PLFA) method was used to determine the microbial community in soil. The low-level experimental warming did not significantly affect the soil’s total PLFA, fungi, bacteria, arbuscular mycorrhizal fungi(AMF), actinomycetes, gram-positive bacteria(G+), gram-negative bacteria(G–), protozoa, the ratio of fungi to bacteria(F/B ratio), and ratio of G+ to G–(G+/G– ratio) at the 0–10 and 10–20 cm depth. The low-level experimental warming also did not significantly alter the composition of microbial community in soil at the 0–10 and 10–20 cm depth. The high-level experimental warming significantly increased total PLFA by 74.4%, fungi by 78.0%, bacteria by 74.0%, AMF by 66.9%, actinomycetes by 81.4%, G+ by 67.0% and G– by 74.4% at the 0–10 cm depth rather than at 10–20 cm depth. The high-level experimental warming significantly altered microbial community composition in soil at the 0–10 cm depth rather than at 10-20 cm depth. Our findings suggest that the response of microbial communities in soil to warming varied with warming magnitudes in the highland barley system of the Lhasa River.
