Limited aerobic scope(AS)during digestion might be the main constraint on the performance of bodily functions in water-breathing animals.Thus,investigating the postprandial changes in various physiological functions a...Limited aerobic scope(AS)during digestion might be the main constraint on the performance of bodily functions in water-breathing animals.Thus,investigating the postprandial changes in various physiological functions and determining the existence of a shared common pattern because of possible dependence on residual AS during digestion in freshwaterfish species are very important in conservation physiology.All species from slow-flow habitats showed impaired swimming speed while digesting,whereas all species from fast-flow habitats showed strong swimming performance,which was unchanged while digesting.Only two species from slow-flow habitats showed impaired heat tolerance during digestion,suggesting that whether oxygen limitation is involved in the heat tolerance process is species-specific.Three species from slow-or intermediate-flow habitats showed impaired hypoxia tolerance during digestion because feeding metabolism cannot cease completely under hypoxia.Overall,there was no common pattern in postprandial changes in different physiological functions because:(1)the digestion process was suppressed under oxygen-limiting conditions,(2)the residual AS decreased during digestion,and(3)performance was related to residual AS,while digestion was context-dependent and species-specific.However,digestion generally showed a stronger effect on bodily functions in species from slow-flow habitats,whereas it showed no impairment infishes from fast-flow habitats.Nevertheless,the postprandial change in physiological functions varies with habitat,possibly due to divergent selective pressure on such functions.More importantly,the present study suggests that a precise prediction of how freshwaterfish populations will respond to global climate change needs to incorporate data from postprandialfishes.展开更多
The dioecious plant,Hippophae rhamnoides,is a pioneer species in community succession on the Qinghai-Tibet Plateau(QTP),plays great roles in various ecosystem services.However,the males and females of the species diff...The dioecious plant,Hippophae rhamnoides,is a pioneer species in community succession on the Qinghai-Tibet Plateau(QTP),plays great roles in various ecosystem services.However,the males and females of the species differ both in their morphology and physiology,resulting in a change in the ratio of male to female plants depending on the environment.To further explore the functional traits critical to this sex-based distinctive response in the alpine grassland,we have surveyed the sex ratios,measured their photosynthetic parameters,height,leaf area and biomass allocation.The results showed that(i)The males had higher Pn,light saturation point,apparent quantum efficiency,A_(max)and lower water-use efficiency(WUE),which exhibited higher utilization efficiency or tolerance to strong light,while the females indicated higher utilization efficiency for low light and water.And it showed sex-specific biomass allocation patterns.(ii)H.rhamnoides populations across the successional stages all showed a male-biased sexual allocation,which was closely related to sex-specific WUE,Pn,root biomass/total biomass and root-crown ratio.(iii)The leaf traits of H.rhamnoides changed from higher N_(area),P_(area)and leaf mass per area in the early and late to lower in the middle,which meant they moved their growth strategy from resource rapid acquisition to conservation as the succession progressed.(iv)The increasing soil total phosphorus mostly contributed to regulating the sex bias of populations and variations of traits during the succession.The results are vital for the management of grassland degradation and restoration due to shrub encroachment on the QTP.展开更多
基金funded by the National Natural Science Foundation of China(31172096,31670418)the Science and Technology Research Program of Chongqing Municipal Education Commission(KJQN201900534,KJQN202000538).
文摘Limited aerobic scope(AS)during digestion might be the main constraint on the performance of bodily functions in water-breathing animals.Thus,investigating the postprandial changes in various physiological functions and determining the existence of a shared common pattern because of possible dependence on residual AS during digestion in freshwaterfish species are very important in conservation physiology.All species from slow-flow habitats showed impaired swimming speed while digesting,whereas all species from fast-flow habitats showed strong swimming performance,which was unchanged while digesting.Only two species from slow-flow habitats showed impaired heat tolerance during digestion,suggesting that whether oxygen limitation is involved in the heat tolerance process is species-specific.Three species from slow-or intermediate-flow habitats showed impaired hypoxia tolerance during digestion because feeding metabolism cannot cease completely under hypoxia.Overall,there was no common pattern in postprandial changes in different physiological functions because:(1)the digestion process was suppressed under oxygen-limiting conditions,(2)the residual AS decreased during digestion,and(3)performance was related to residual AS,while digestion was context-dependent and species-specific.However,digestion generally showed a stronger effect on bodily functions in species from slow-flow habitats,whereas it showed no impairment infishes from fast-flow habitats.Nevertheless,the postprandial change in physiological functions varies with habitat,possibly due to divergent selective pressure on such functions.More importantly,the present study suggests that a precise prediction of how freshwaterfish populations will respond to global climate change needs to incorporate data from postprandialfishes.
基金supported by National Natural Science Foundation of China(32201525)the Gansu province’s Key Research and Development Plan(21YF5NA069)+2 种基金the Longyuan Talent Youth Innovation and Entrepreneurship Team projectthe Key Laboratory of Eco-functional Polymer Materials of the Ministry of Education(YDZX20216200001007)the Foreign Expert Introduction Special Project of Gansu Province(22JR10KA010).
文摘The dioecious plant,Hippophae rhamnoides,is a pioneer species in community succession on the Qinghai-Tibet Plateau(QTP),plays great roles in various ecosystem services.However,the males and females of the species differ both in their morphology and physiology,resulting in a change in the ratio of male to female plants depending on the environment.To further explore the functional traits critical to this sex-based distinctive response in the alpine grassland,we have surveyed the sex ratios,measured their photosynthetic parameters,height,leaf area and biomass allocation.The results showed that(i)The males had higher Pn,light saturation point,apparent quantum efficiency,A_(max)and lower water-use efficiency(WUE),which exhibited higher utilization efficiency or tolerance to strong light,while the females indicated higher utilization efficiency for low light and water.And it showed sex-specific biomass allocation patterns.(ii)H.rhamnoides populations across the successional stages all showed a male-biased sexual allocation,which was closely related to sex-specific WUE,Pn,root biomass/total biomass and root-crown ratio.(iii)The leaf traits of H.rhamnoides changed from higher N_(area),P_(area)and leaf mass per area in the early and late to lower in the middle,which meant they moved their growth strategy from resource rapid acquisition to conservation as the succession progressed.(iv)The increasing soil total phosphorus mostly contributed to regulating the sex bias of populations and variations of traits during the succession.The results are vital for the management of grassland degradation and restoration due to shrub encroachment on the QTP.
