Understanding the relationship between forest management and water use efficiency(WUE)is important for evaluating forest adaptability to climate change.However,the effects of thinning and understory removal on WUE and...Understanding the relationship between forest management and water use efficiency(WUE)is important for evaluating forest adaptability to climate change.However,the effects of thinning and understory removal on WUE and its key controlling processes are not well understood,which limits our comprehension of the physiological mechanisms of various management practices.In this study,four forest management measures(no thinning:NT;understory removal:UR;light thinning:LT;and heavy thinning:HT)were carried out in Pinus massoniana plantations in a subtropical region of China.Photosynthetic capacity and needle stable carbon isotope composition(δ^(13)C)were measured to assess instantaneous water use efficiency(WUE_(inst))and long-term water use efficiency(WUE_(i)).Multiple regression models and structural equation modelling(SEM)identified the effects of soil properties and physiological performances on WUE_(inst)and WUE_(i).The results show that WUE_(inst)values among the four treatments were insignificant.However,compared with the NT stand(35.8μmol·mol^(-1)),WUE_(i)values significantly increased to 41.7μmol·mol^(-1)in the UR,50.1μmol·mol^(-1)in the LT and 46.6μmol·mol^(-1)in HT treatments,largely explained by photosynthetic capacity and soil water content.Understory removal did not change physiological performance(needle water potential and photosynthetic capacity).Thinning increased the net photosynthetic rate(A_n)but not stomatal conductance(g_s)or predawn needle water potential(ψ_(pd)),implying that the improvement in water use efficiency for thinned stands was largely driven by radiation interception than by soil water availability.In general,thinning may be an appropriate management measure to promote P.massoniana WUE to cope with seasonal droughts under future extreme climates.展开更多
In this study,we investigated the separation of iron and scandium from Sc-bearing red mud.The red mud object of our study contained 31.11 wt%total iron(TFe),0.0045 wt%Sc,hematite(Fe_(2)O_(3))and ferrosilite(FeO·S...In this study,we investigated the separation of iron and scandium from Sc-bearing red mud.The red mud object of our study contained 31.11 wt%total iron(TFe),0.0045 wt%Sc,hematite(Fe_(2)O_(3))and ferrosilite(FeO·SiO_(2))as the main Fe-bearing minerals.The Sc-bearing red mud was treated by a novel deep reduction roasting and magnetic separation process that includes the addition of coke and CaO to extract Fe and enriching Sc from the Sc-bearing red mud.The addition of coke and CaO enhances the transformation of hematite(Fe_(2)O_(3))to metallic iron(Fe~0)and magnetite(Fe_(3)O_(4))as well as the transformation of ferrosilite into metallic iron(Fe~0).The test results show that utilizing the new process a Fe concentrate with a TFe content of 81.22 wt%and Fe recovery of 92.96%was obtained.Furthermore,magnetic separation tailings with Sc content of 0.0062 wt%and Sc recovery of 98.65%were also obtained.The test results were achieved under the following process conditions:roasting temperature of 1373 K,roasting time of 45 min,calcium oxide dosage of 20 wt%,coke dosage of 25 wt%,grinding fineness of90%<0.04 mm,and magnetic field intensity of 0.24 T.The major minerals in the Fe concentrate are metallic iron(Fe~0)and magnetite(Fe_(3)O_(4)).The main minerals in the magnetic separation tailings with a low TFe content of 2.62%are CaO·SiO_(2),Na_(2)O·SiO_(2),FeO·SiO_(2),Ca_(3)Fe_(2)Si_(3)O_(12),CaAl_(2)SiO_6 and CaFe(SiO_(3))_(2).展开更多
Aims West Ordos Desert(WOD)in Inner Mongolia of China is charac-terized by unique geographical and ecological features to avoid the direct invasion of Quaternary Continental Glaciation,so it hosts many endangered reli...Aims West Ordos Desert(WOD)in Inner Mongolia of China is charac-terized by unique geographical and ecological features to avoid the direct invasion of Quaternary Continental Glaciation,so it hosts many endangered relic species such as Tetraena mongol-ica,Ammopiptanthus mongolicus and Potaninia mongolica from Tertiary.However,how these plants utilize available water sources remains unknown.The objective of this study was to investigate the water utilization strategies of selected rare and endangered plant species in WOD by comparing hydrogen isotope ratios between their xylem water and possible water sources following four rainfall events of varying-intensities.Methods We measured the hydrogen isotope ratios of xylem water from T.mongolica,A.mongolicus and P.mongolica and an accom-panying species Sarcozygium xanthoxylum and potential water sources(including precipitation and soil water in different soil layers from 0 to 150 cm)over 9 days following each of four varying-intensity rainfall events during the summer of 2012.And then calculated the percentage utilization of potential water sources by each species after each rainfall events using the linear mixing model.We also made the measurements of soil moisture and root biomass in favor of interpretation of plant water use strategies.Important Findings Tetraena mongolica,A.mongolicus and S.xanthoxylum primarily relied on deep soil water,whereas P.mongolica depended predomi-nantly on rainwater.These rare and endangered desert plants had differential utilizations of available water sources,so some com-petition for limited water existed among some species.Tetraena mongolica had a competitive relationship in absorption of soil moisture with the same family species S.xanthoxylum,suggesting that T.mongolica and S.xanthoxylum should be restored separately at different areas in the WOD.Overall,this study provides a better understanding of water use strategies of these four plants and scien-tific evidence for protecting rare and endangered plants,maintain-ing regional species diversity,and developing effective vegetation restoration plans in the WOD.展开更多
Premature ovarian insufficiency(POI) affects seriously physical and mental health of the patients. Studies show that acupuncture may be promising in treating POI. yet evidence is insufficient. International patient ...Premature ovarian insufficiency(POI) affects seriously physical and mental health of the patients. Studies show that acupuncture may be promising in treating POI. yet evidence is insufficient. International patient registry, one form of observational study, is designed for evaluating effectiveness and safety of acupuncture in real-world clinical settings. We will face a series of opportunities and challenges. The opportunities are as follows:(1) Interdisciplinary cooperation can improve the effect of acupuncture for POI.(2) The protocol for acupuncture to treat POI has room for improvement.(3) The patient registry study can make up the shortcomings of randomized controlled trials.(4) The patient registry study can collect real-world data and explore responses of different populations to acupuncture and can be the foundation for the successive studies. International patient registry may face technological, ethical and financial challenges, while the established International Patient Registry Platform of Acupuncture-Moxibustion(www.amreg.org:8082/v3) is actively responding to these challenges. Till now there have been more than 300 patients of POI enrolled on this platform.展开更多
基金supported by the National Key Research and Development Program of China(2016YFD0600201)the National Nonprofit Institute Research Grant of CAF(CAFYBB2017ZB003)+1 种基金the National Natural Science Foundation of China(3187071631670720)。
文摘Understanding the relationship between forest management and water use efficiency(WUE)is important for evaluating forest adaptability to climate change.However,the effects of thinning and understory removal on WUE and its key controlling processes are not well understood,which limits our comprehension of the physiological mechanisms of various management practices.In this study,four forest management measures(no thinning:NT;understory removal:UR;light thinning:LT;and heavy thinning:HT)were carried out in Pinus massoniana plantations in a subtropical region of China.Photosynthetic capacity and needle stable carbon isotope composition(δ^(13)C)were measured to assess instantaneous water use efficiency(WUE_(inst))and long-term water use efficiency(WUE_(i)).Multiple regression models and structural equation modelling(SEM)identified the effects of soil properties and physiological performances on WUE_(inst)and WUE_(i).The results show that WUE_(inst)values among the four treatments were insignificant.However,compared with the NT stand(35.8μmol·mol^(-1)),WUE_(i)values significantly increased to 41.7μmol·mol^(-1)in the UR,50.1μmol·mol^(-1)in the LT and 46.6μmol·mol^(-1)in HT treatments,largely explained by photosynthetic capacity and soil water content.Understory removal did not change physiological performance(needle water potential and photosynthetic capacity).Thinning increased the net photosynthetic rate(A_n)but not stomatal conductance(g_s)or predawn needle water potential(ψ_(pd)),implying that the improvement in water use efficiency for thinned stands was largely driven by radiation interception than by soil water availability.In general,thinning may be an appropriate management measure to promote P.massoniana WUE to cope with seasonal droughts under future extreme climates.
基金Project supported by the Sichuan Science and Technology Program(2022YFS0462,2021YJ0057,2021YFG0268)the China Postdoctoral Science Foundation(2014M560734)。
文摘In this study,we investigated the separation of iron and scandium from Sc-bearing red mud.The red mud object of our study contained 31.11 wt%total iron(TFe),0.0045 wt%Sc,hematite(Fe_(2)O_(3))and ferrosilite(FeO·SiO_(2))as the main Fe-bearing minerals.The Sc-bearing red mud was treated by a novel deep reduction roasting and magnetic separation process that includes the addition of coke and CaO to extract Fe and enriching Sc from the Sc-bearing red mud.The addition of coke and CaO enhances the transformation of hematite(Fe_(2)O_(3))to metallic iron(Fe~0)and magnetite(Fe_(3)O_(4))as well as the transformation of ferrosilite into metallic iron(Fe~0).The test results show that utilizing the new process a Fe concentrate with a TFe content of 81.22 wt%and Fe recovery of 92.96%was obtained.Furthermore,magnetic separation tailings with Sc content of 0.0062 wt%and Sc recovery of 98.65%were also obtained.The test results were achieved under the following process conditions:roasting temperature of 1373 K,roasting time of 45 min,calcium oxide dosage of 20 wt%,coke dosage of 25 wt%,grinding fineness of90%<0.04 mm,and magnetic field intensity of 0.24 T.The major minerals in the Fe concentrate are metallic iron(Fe~0)and magnetite(Fe_(3)O_(4)).The main minerals in the magnetic separation tailings with a low TFe content of 2.62%are CaO·SiO_(2),Na_(2)O·SiO_(2),FeO·SiO_(2),Ca_(3)Fe_(2)Si_(3)O_(12),CaAl_(2)SiO_6 and CaFe(SiO_(3))_(2).
基金National Natural Science Foundation of China(31170661,31290223)Special Research Program for Public-Welfare Forestry(201504423)Agriculture Science Technology Achievement Transformation Fund(2013GB24320620).
文摘Aims West Ordos Desert(WOD)in Inner Mongolia of China is charac-terized by unique geographical and ecological features to avoid the direct invasion of Quaternary Continental Glaciation,so it hosts many endangered relic species such as Tetraena mongol-ica,Ammopiptanthus mongolicus and Potaninia mongolica from Tertiary.However,how these plants utilize available water sources remains unknown.The objective of this study was to investigate the water utilization strategies of selected rare and endangered plant species in WOD by comparing hydrogen isotope ratios between their xylem water and possible water sources following four rainfall events of varying-intensities.Methods We measured the hydrogen isotope ratios of xylem water from T.mongolica,A.mongolicus and P.mongolica and an accom-panying species Sarcozygium xanthoxylum and potential water sources(including precipitation and soil water in different soil layers from 0 to 150 cm)over 9 days following each of four varying-intensity rainfall events during the summer of 2012.And then calculated the percentage utilization of potential water sources by each species after each rainfall events using the linear mixing model.We also made the measurements of soil moisture and root biomass in favor of interpretation of plant water use strategies.Important Findings Tetraena mongolica,A.mongolicus and S.xanthoxylum primarily relied on deep soil water,whereas P.mongolica depended predomi-nantly on rainwater.These rare and endangered desert plants had differential utilizations of available water sources,so some com-petition for limited water existed among some species.Tetraena mongolica had a competitive relationship in absorption of soil moisture with the same family species S.xanthoxylum,suggesting that T.mongolica and S.xanthoxylum should be restored separately at different areas in the WOD.Overall,this study provides a better understanding of water use strategies of these four plants and scien-tific evidence for protecting rare and endangered plants,maintain-ing regional species diversity,and developing effective vegetation restoration plans in the WOD.
基金Supported by Ministry of Science and Technology of the People's Republic of China through the Twelfth Five-Year National Science and Technology Pillar Program(2012BAI24B02)~~
文摘Premature ovarian insufficiency(POI) affects seriously physical and mental health of the patients. Studies show that acupuncture may be promising in treating POI. yet evidence is insufficient. International patient registry, one form of observational study, is designed for evaluating effectiveness and safety of acupuncture in real-world clinical settings. We will face a series of opportunities and challenges. The opportunities are as follows:(1) Interdisciplinary cooperation can improve the effect of acupuncture for POI.(2) The protocol for acupuncture to treat POI has room for improvement.(3) The patient registry study can make up the shortcomings of randomized controlled trials.(4) The patient registry study can collect real-world data and explore responses of different populations to acupuncture and can be the foundation for the successive studies. International patient registry may face technological, ethical and financial challenges, while the established International Patient Registry Platform of Acupuncture-Moxibustion(www.amreg.org:8082/v3) is actively responding to these challenges. Till now there have been more than 300 patients of POI enrolled on this platform.