Entity

Time filter

Source Type


Wang S.P.,CAS Institute of Tibetan Plateau Research | Meng F.D.,CAS Institute of Tibetan Plateau Research | Meng F.D.,Chinese Academy of Sciences | Duan J.C.,CAS Northwest Institute of Plateau Biology | And 22 more authors.
Ecology | Year: 2014

Understanding how flowering phenology responds to warming and cooling (i.e., symmetric or asymmetric response) is needed to predict the response of flowering phenology to future climate change that will happen with the occurrence of warm and cold years superimposed upon a long-term trend. A three-year reciprocal translocation experiment was performed along an elevation gradient from 3200 m to 3800 m in the Tibetan Plateau for six alpine plants. Transplanting to lower elevation (warming) advanced the first flowering date (FFD) and transplanting to higher elevation (cooling) had the opposite effect. The FFD of early spring flowering plants (ESF) was four times less sensitive to warming than to cooling (by -2.1 d/°C and 8.4 d/°C, respectively), while midsummer flowering plants (MSF) were about twice as sensitive to warming than to cooling (-8.0 d/°C and 4.9 d/°C, respectively). Compared with pooled warming and cooling data, warming alone significantly underpredicted 3.1 d/°C for ESF and overestimated 1.7 d/°C for MSF. These results suggest that future empirical and experimental studies should consider nonlinear temperature responses that can cause such warming-cooling asymmetries as well as differing life strategies (ESF vs. MSF) among plant species. © 2014 by the Ecological Society of America.


Cao H.,CAS Northwest Institute of Plateau Biology | Cao H.,University of Chinese Academy of Sciences | Zhao X.,CAS Northwest Institute of Plateau Biology | Zhao X.,CAS Chengdu Institute of Biology | And 8 more authors.
Ecology and Evolution | Year: 2015

Understanding the plant-pest interaction under warming with grazing conditions is critical to predict the response of alpine meadow to future climate change. We investigated the effects of experimental warming and grazing on the interaction between plants and the grassland caterpillar Gynaephora menyuanensis in an alpine meadow on the Tibetan Plateau in 2010 and 2011. Our results showed that grazing significantly increased nitrogen concentration in graminoids and sward openness with a lower sward height, sward coverage, and plant litter mass in the community. Grazing significantly increased G. menyuanensis body size and potential fecundity in 2010. The increases in female body size were about twofold greater than in males. In addition, grazing significantly increased G. menyuanensis density and its negative effects on aboveground biomass and graminoid coverage in 2011. We found that G. menyuanensis body size was significantly positively correlated with nitrogen concentration in graminoids but negatively correlated with plant litter mass. Even though warming did not significantly increased G. menyuanensis performance and the negative effects of G. menyuanensis on alpine meadow, the increases in G. menyuanensis growth rate and its negative effect on aboveground biomass under the warming with grazing treatment were significantly higher than those under the no warming with grazing treatment. The positive effects of grazing on G. menyuanensis performance and its damage were exacerbated by the warming treatment. Our results suggest that the fitness of G. menyuanensis would increase under future warming with grazing conditions, thereby posing a greater risk to alpine meadow and livestock production. © 2015 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.


Duan J.,CAS Institute of Tibetan Plateau Research | Duan J.,Binhai Research Institute in Tianjin | Wang S.,CAS Institute of Tibetan Plateau Research | Wang S.,CAS Northwest Institute of Plateau Biology | And 13 more authors.
Soil Biology and Biochemistry | Year: 2013

Few studies of the effects of litter diversity on the temperature sensitivity of mixed litter mass loss (MLML) are available. We tested the hypothesis that high litter diversity would reduce the magnitude of effects of climate and environmental change on MLML with 0.5/1 mm litter bags and sampling once after 1 yr of decomposition, using 51 combinations of litter mixtures from 25 dominant species at 3200 and 3800 m elevations on the Tibetan Plateau. Generally, our study supported our hypothesis. High temperature (i.e. lower elevation) reduced the dependency of MLML and non-additive effects on species richness. Species composition significantly affected MLML and its Q10 (i.e. the ratio of litter mass loss rate at a temperature T1 that is 10 °C lower than a temperature T2) when species richness was less than 8. Shrubs significantly decreased the Q10 of MLML when the species richness of litter mixture was less than 4. These findings suggest that the influence of future warming on MLML may depend on the balance between the magnitude of the impacts of climate change on shrub invasion and loss of species diversity in alpine region. © 2012 Elsevier Ltd.


Hu Y.,CAS Institute of Tibetan Plateau Research | Hu Y.,CAS Lanzhou Cold and Arid Regions Environmental and Engineering Research Institute | Jiang L.,CAS Institute of Tibetan Plateau Research | Wang S.,CAS Institute of Tibetan Plateau Research | And 11 more authors.
Agricultural and Forest Meteorology | Year: 2016

Information about the potential effects of climate change, especially cooling, on ecosystem respiration (Re) in alpine meadows is scarce. We determined the effects of warming and cooling on Re on the Tibetan Plateau using a 2-year reciprocal translocation experiment with 4 different vegetation types (3 alpine meadows and 1 alpine shrub differentiated by plant community composition) along an elevation gradient from 3200 to 3800m (with vegetation types E2, E4, E6 and E8 at 3200, 3600, 3800 and 3800m, respectively) during the growing seasons in 2008 and 2009. Mean growing seasonal Re decreased by 13.6, 30.3 and 40.7% per 200m rise in elevation (cooling) for vegetation types E2, E4 and E6, but increased by 1.3, 35.9 and 58.8% per 200m decrease in elevation (warming) for vegetation types E4, E6 and E8, respectively. Soil temperature explained 49.3-64.0% of daily Re variation and aboveground biomass explained 21.5-61.6% of average Re variation of the growing season for all vegetation types, but the effect of soil moisture on Re was small over 2-year. The values of Re temperature sensitivity increased with an increase in elevation for both warming (3.3, 24.3 and 53.5%°C-1 for vegetation types E4, E6 and E8) and cooling (8.0, 19.1 and 24.4%°C-1 for vegetation types E2, E4 and E6), suggesting that alpine meadow at higher elevation was more sensitive to both warming and cooling. Based on the values of Re temperature sensitivity for all pooled vegetation types (25.4, 5.6 and 19.6%°C-1 for warming, cooling and pooled warming and cooling), it could be over-estimated by 23% for warming alone compared with pooled warming and cooling. Therefore, asymmetrical responses of Re to warming and cooling should be taken into account when we evaluate the effect of temperature change on Re using models in the future. © 2015.


Hu Y.,CAS Lanzhou Cold and Arid Regions Environmental and Engineering Research Institute | Hu Y.,Key Laboratory of Stress Physiology and Ecology in Cold and Arid Regions of Gansu Province | Wang Q.,CAS Institute of Tibetan Plateau Research | Wang Q.,University of Chinese Academy of Sciences | And 10 more authors.
Plant and Soil | Year: 2016

Aims: A lacking of understanding about cooling effects on methane (CH4) fluxes and potential asymmetrical responses to warming and cooling causes uncertainty about climate change effects on the atmospheric CH4 concentration. We investigated CH4 fluxes in an alpine meadow on the Tibetan Plateau in response to climate warming and cooling. Methods: A 2-year reciprocal translocation experiment was implemented to simulate climate warming (i.e. downward translocation) and cooling (i.e. upward translocation) along an elevation gradient with four different vegetation types (at 3200, 3400, 3600 and 3800 m elevation) during the growing season (May to October) in 2008 and 2009. Results: Although the effects of warming and cooling varied depending on vegetation type, elevation and timescale (i.e., daily and seasonally), warming increased average seasonal CH4 uptake by 60 %, while cooling reduced it by 19 % across all vegetation types, based on a 1.3–5.1 °C difference in soil temperature at 20 cm depth. Soil temperature over the range of 4–10 °C explained 11–25 % of the variation in average seasonal CH4 fluxes, while there was no relationship with soil moisture over the range of 13–39 % and soil NH4 +-N and NO3 −N content. Methane uptake was more sensitive to warming than to cooling. Conclusions: Because of warming and cooling spells in the alpine region, warming effects on CH4 uptake would be over-estimated by 64 % if cooling effects on it are not considered. Our findings suggest that asymmetrical responses of CH4 fluxes to warming and cooling should be taken into account when evaluating the effects of climate change on CH4 uptake in the alpine meadow on the Tibetan plateau. © 2016 Springer International Publishing Switzerland

Discover hidden collaborations