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Qiuyi Wang - One of the best experts on this subject based on the ideXlab platform.
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climatic effects on plant species distribution within the forest Steppe ecotone in northern china
Applied Vegetation Science, 2015Co-Authors: Hongyan Liu, Yi Yin, Qiuyi WangAbstract:Questions As a narrow belt extending from the northern to the southern edges of the temperate forest zone, there is not only a strong temperature gradient and a long geographic distance but also a very sharp precipitation gradient in the temperate forest–Steppe in northern China at a regional scale. Patches of forest are scattered in the Steppe matrix. At the local scale, each forest patch shows a climatic gradient from patch centre to its edge and to the open Steppe. How do these climatic gradients determine plant species distribution for the forest and Steppe within this ecotone? Location The temperate forest–Steppe ecotone in northern China. Methods Species were recorded in paired plots of forest and Steppe at 68 sites. t-tests were conducted to show differences in floristic composition among forest types. Mantel tests were applied to correlate site-level floristic distances with geographic and climatic distances for forest and Steppe separately as well as for their combination. Floristic differences between paired plots of forest and Steppe at each site were correlated to MAT, MAP and geographic factors at that site. Results There was no significant floristic difference in the understorey of forests dominated by Betula platyphylla, B. dahurica or Populus davidiana. Quercus mongolica forests, however, were floristically dissimilar to the other forest types. Floristic distance of both forests and Steppes were significantly correlated with ΔMAT and geographic distance, while there was a significant correlation with ΔMAP for forests only, but not for Steppes. The floristic difference between forest understorey and Steppe plots within each site showed no significant correlations with climatic or geographic factors. Conclusions The plant species distribution of both forest and Steppe was more dependent on temperature than on precipitation gradients. The floristic distance between the forest understorey and Steppe plots within sites seemed to depend on factors other than climate.
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special feature east asian forests climatic effects on plant species distribution within the forest Steppe ecotone in northern china
2014Co-Authors: Hongyan Liu, Yi Yin, Qiuyi WangAbstract:Questions: As a narrow belt extending from the northern to the southern edges of the temperate forest zone, there is not only a strong temperature gradient and a long geographic distance but also a very sharp precipitation gradient in the temperate forest–Steppe in northern China at a regional scale. Patches of forest are scattered in the Steppe matrix. At the local scale, each forest patch shows a climatic gradient from patch centre to its edge and to the open Steppe. How do these climatic gradients determine plant species distribution for the forest and Steppe within this ecotone? Location: The temperate forest–Steppe ecotone in northern China. Methods: Species were recorded in paired plots of forest and Steppe at 68 sites. t-tests were conducted to show differences in floristic composition among forest types. Mantel tests were applied to correlate site-level floristic distances with geographic and climatic distances for forest and Steppe separately as well as for their combination. Floristic differences between paired plots of forest and Steppe at each site were correlated toMAT, MAP and geographic factors at that site. Results: There was no significant floristic difference in the understorey of forests dominated by Betula platyphylla, B. dahurica or Populus davidiana. Quercus mongolica forests, however, were floristically dissimilar to the other forest types. Floristic distance of both forests and Steppes were significantly correlated with DMAT and geographic distance, while there was a significant correlation with DMAP for forests only, but not for Steppes. The floristic difference between forest understorey and Steppe plots within each site showed no significant correlations with climatic or geographic factors. Conclusions: The plant species distribution of both forest and Steppe was more dependent on temperature than on precipitation gradients. The floristic distance between the forest understorey and Steppe plots within sites seemed to depend on factors other than climate.
Weiwei Chen - One of the best experts on this subject based on the ideXlab platform.
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Effects of increasing precipitation and nitrogen deposition on CH4 and N2O fluxes and ecosystem respiration in a degraded Steppe in Inner Mongolia, China
Geoderma, 2013Co-Authors: Weiwei Chen, Xunhua Zheng, Qing Chen, Benjamin Wolf, Klaus Butterbach-bahl, Nicolas Brüggemann, Shan LinAbstract:Abstract Most rangelands in temperate semiarid Steppes have degraded due to over-grazing. However, the exchanges of greenhouse gases (GHG) between the degraded Steppes have been poorly studied. In this study we investigated the fluxes of methane (CH4), nitrous oxide (N2O) and carbon dioxide (CO2) as ecosystem respiration during the growing season and their responses to simulated increases in water availability and nitrogen supply at a degraded Steppe in Inner Mongolia, China. Temporal variation of ecosystem respiration (i.e., CO2 flux) was dominated by the interaction of soil temperature and moisture, whereas N2O emissions were mainly dependent on soil moisture. The ambient degraded Steppe (i.e., not receiving additional water and nitrogen supplies) was a sink of CH4 (− 1.41 ± 0.04 kg C ha− 1) and a source of N2O (0.17 ± 0.09 kg N ha− 1) during the growing season, respectively. Increases in water and nitrogen supplies significantly stimulated N2O emissions by 65–94% (p
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annual methane uptake by temperate semiarid Steppes as regulated by stocking rates aboveground plant biomass and topsoil air permeability
Global Change Biology, 2011Co-Authors: Xunhua Zheng, Weiwei Chen, Benjamin Wolf, Nicolas Brüggemann, Zhisheng Yao, Klaus Butterbachbahl, Chunyan Liu, Shenghui HanAbstract:Overgrazing-induced degradation of temperate semiarid Steppes may affect the soil sink for atmospheric methane (CH4). However, previous studies have primarily focused on the growing season and on single grazing patterns. Thus, the response of annual CH4 uptake by Steppes compared with various grazing practices is uncertain. In this study, we investigated the effects of grazing on the annual CH4 uptake by two typical Eurasian semiarid Steppes (the Stipa grandis Steppe and the Leymus chinensis Steppe) located in Inner Mongolia, China. The CH4 fluxes were measured yearround using static chambers and gas chromatography at 12 field sites that differed primarily in grazing intensities. Our results indicated that Steppe soils were CH4 sinks throughout the year. The annual CH4 uptake correlated with stocking rates, whereas the seasonality of CH4 uptake was primarily dominated by temperature. The annual CH4 uptake at all sites averaged 3.7 � 0.7 kg C ha � 1 yr � 1 (range: 2.3–4.5), where approximately 35% (range: 23–40%) occurred during the nongrowing season. Light-to-moderate grazing (stocking rate � 1 sheep ha � 1 yr � 1 ) did not significantly change the annual CH4 uptake compared with ungrazed Steppes, but heavy grazing reduced annual CH4 uptake significantly (by 24–31%, Po0.05). These findings imply that easing the pressure of heavily grazed Steppes (e.g. moving to light or moderate stocking rates) would help restore Steppe soil sinks for atmospheric CH4. The empirical equations based on the significant relationships between annual CH4 uptake and stocking rates, aboveground plant biomass and topsoil air permeability (Po0.01) could provide simple approaches for the estimation of regional CH4 uptake by temperate semiarid Steppes.
Georg Guggenberger - One of the best experts on this subject based on the ideXlab platform.
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limited protection of macro aggregate occluded organic carbon in siberian Steppe soils
Biogeosciences, 2017Co-Authors: Norbert Bischoff, Alexander Puzanov, Marina Silanteva, Anna Grebennikova, Olga Shibistova, Robert Mikutta, Georg GuggenbergerAbstract:Abstract. Macro-aggregates especially in agricultural Steppe soils are supposed to play a vital role for soil organic carbon (OC) stabilization at a decadal timescale. While most research on soil OC stabilization in Steppes focused on North American prairie soils of the Great Plains with information mainly provided by short-term incubation experiments, little is known about the agricultural Steppes in southwestern Siberia, though they belong to the greatest conversion areas in the world and occupy an area larger than that in the Great Plains. To quantify the proportion of macro-aggregate-protected OC under different land use as function of land use intensity and time since land use change (LUC) from pasture to arable land in Siberian Steppe soils, we determined OC mineralization rates of intact (250–2000 µm) and crushed (
Hongyan Liu - One of the best experts on this subject based on the ideXlab platform.
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climatic effects on plant species distribution within the forest Steppe ecotone in northern china
Applied Vegetation Science, 2015Co-Authors: Hongyan Liu, Yi Yin, Qiuyi WangAbstract:Questions As a narrow belt extending from the northern to the southern edges of the temperate forest zone, there is not only a strong temperature gradient and a long geographic distance but also a very sharp precipitation gradient in the temperate forest–Steppe in northern China at a regional scale. Patches of forest are scattered in the Steppe matrix. At the local scale, each forest patch shows a climatic gradient from patch centre to its edge and to the open Steppe. How do these climatic gradients determine plant species distribution for the forest and Steppe within this ecotone? Location The temperate forest–Steppe ecotone in northern China. Methods Species were recorded in paired plots of forest and Steppe at 68 sites. t-tests were conducted to show differences in floristic composition among forest types. Mantel tests were applied to correlate site-level floristic distances with geographic and climatic distances for forest and Steppe separately as well as for their combination. Floristic differences between paired plots of forest and Steppe at each site were correlated to MAT, MAP and geographic factors at that site. Results There was no significant floristic difference in the understorey of forests dominated by Betula platyphylla, B. dahurica or Populus davidiana. Quercus mongolica forests, however, were floristically dissimilar to the other forest types. Floristic distance of both forests and Steppes were significantly correlated with ΔMAT and geographic distance, while there was a significant correlation with ΔMAP for forests only, but not for Steppes. The floristic difference between forest understorey and Steppe plots within each site showed no significant correlations with climatic or geographic factors. Conclusions The plant species distribution of both forest and Steppe was more dependent on temperature than on precipitation gradients. The floristic distance between the forest understorey and Steppe plots within sites seemed to depend on factors other than climate.
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special feature east asian forests climatic effects on plant species distribution within the forest Steppe ecotone in northern china
2014Co-Authors: Hongyan Liu, Yi Yin, Qiuyi WangAbstract:Questions: As a narrow belt extending from the northern to the southern edges of the temperate forest zone, there is not only a strong temperature gradient and a long geographic distance but also a very sharp precipitation gradient in the temperate forest–Steppe in northern China at a regional scale. Patches of forest are scattered in the Steppe matrix. At the local scale, each forest patch shows a climatic gradient from patch centre to its edge and to the open Steppe. How do these climatic gradients determine plant species distribution for the forest and Steppe within this ecotone? Location: The temperate forest–Steppe ecotone in northern China. Methods: Species were recorded in paired plots of forest and Steppe at 68 sites. t-tests were conducted to show differences in floristic composition among forest types. Mantel tests were applied to correlate site-level floristic distances with geographic and climatic distances for forest and Steppe separately as well as for their combination. Floristic differences between paired plots of forest and Steppe at each site were correlated toMAT, MAP and geographic factors at that site. Results: There was no significant floristic difference in the understorey of forests dominated by Betula platyphylla, B. dahurica or Populus davidiana. Quercus mongolica forests, however, were floristically dissimilar to the other forest types. Floristic distance of both forests and Steppes were significantly correlated with DMAT and geographic distance, while there was a significant correlation with DMAP for forests only, but not for Steppes. The floristic difference between forest understorey and Steppe plots within each site showed no significant correlations with climatic or geographic factors. Conclusions: The plant species distribution of both forest and Steppe was more dependent on temperature than on precipitation gradients. The floristic distance between the forest understorey and Steppe plots within sites seemed to depend on factors other than climate.
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China Forest-Steppe Ecotone Database
Biodiversity & Ecology, 2012Co-Authors: Fengjun Zhao, Hongyan LiuAbstract:The China Forest Steppe Ecotone Database (GIVD ID AS-CN-001) contains releves of the forest-Steppe ecotone, typical Steppe and desert Steppe in central part of Inner Mongolia, China as well as of the Zamin Ude region in Mongolia. Releves of the forest-Steppe ecotone were recorded during the 1990s. The communities in the forest-Steppe ecotone are classified in a phytocoenological way. 12 major types of forest, shrubland, meadow, fen, open woodland and Steppe are differentiated and described according to 133 releves. Due to limited releves, the plant communities are named by their dominant species: 1. Quercus mongolicawoodland; 2. Betula platyphylla-woodland; 3. Betula dahurica-woodland; 4. Populus davidiana-woodland; 5. Picea meyeri-woodland; 6. Pinus tabulaeformis-woodland; 7. Ostryopsis davidiana-shrubland; 8. Polygonum viviparum-meadow; 9. Ranunculus japonica-fen; 10. Stipa baicalensis-Steppe; 11. Leymus chinensis-Steppe; 12. Ulmus pumila-open woodland. Other plant community types with less than 5 releves are Larix principis-ruprechtii-woodland, Pinus Betula fruticosa-scrub, Stipa krylovii-Steppe, Filifolium sibiricumSteppe and Thymus serphyllum-Steppe. During the 2000s, we extended our survey further to the dryer region, including typical Steppes and desert Steppes in central Inner Mongolia of China, including the huge sandy sheets, Otindag and Mu Us. Besides releve records, we systematically collected 344 soil profiles, with C, N content measured for most of the profiles, as well as grain sizes for all the profiles.
Larisa Frolova - One of the best experts on this subject based on the ideXlab platform.
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Mid-late Holocene environmental history of Kulunda, southern West Siberia: vegetation, climate and humans
Quaternary Science Reviews, 2012Co-Authors: Natalia Rudaya, Danis Nourgaliev, Olga Palagushkina, Dmitry V. Papin, Larisa Nazarova, Larisa FrolovaAbstract:An environmental reconstruction of mid-late Holocene vegetation, climate and lake dynamics was inferred from pollen and diatom records of Lake Big Yarovoe in Kulunda, southern West Siberia. The reconstruction suggests a general prevalence of Steppe during the last 4.4 ka. Under a relatively warm and dry climate, open semi-desert and dry Steppes with patchy birch forest spread between 4.4 and 3.75 ka BP. The largest development of conifer forest started in Kulunda after 3.75 ka BP. The onset of the Late Holocene is characterised by the dominance of Steppe with birch and pine forests in the lowlands and river valleys. After AD 1860, open Steppe and semi-desert vegetation with fragmentary birch forest have been dominant in Kulunda, along with a sharp reduction of conifers. These results are in agreement with the general pattern of the Holocene environmental history of the surrounding areas, including the Baraba forest-Steppe, Kazakh Upland and Altai Mountains. The penetration of coniferous forest into the Kulunda Steppe after 3.75 ka BP was related to its geographical location northwest of the Altai Mountains. The economic activities of the ancient population of Kulunda depended on the environmental changes during the Holocene.
