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Characterizing nitric oxide emissions from two typical alpine ecosystems

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Journal of Environmental Sciences 2019年第3期31卷 312-322页

作者： Fei Lin Chunyan Liu Xiaoxia Hu Yongfeng Fu Xunhua Zheng Rui Wang Wei Zhang Guangmin Cao State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry (LAPC) Institute of Atmospheric Physics Chinese Academy of Sciences College of Earth and Planetary Sciences University of Chinese Academy of Sciences Northwest Institute of Plateau Biology Chinese Academy of Sciences

portion of alpine meadows has been and will continue to be cultivated due to the concurrent increasing demands for animal-and crop-oriented foods and global warming.However, it remains unclear how these long-term changes in land use will affect nitric oxide(NO) emission. At a field site with a calcareous soil on the Qinghai-Tibetan Plateau,the authors measured the year-round NO fluxes and related variables in a typically wintergrazed natural alpine meadow(NAM) and its adjacent forage oat field(FOF). The results showed that long-term plow tillage, fertilization and growing forage oats significantly yielded ca. 2.7 times more(p meadows and/or fields cultivated with forage oats can be predicted by simultaneous observations of these four soil variables.

关键词： Alpine meadow Annual NO fluxes Non-growing season Freeze–thaw period Land use change Global warming

The weak effects of fencing on ecosystem respiration,CH4,and N2O fluxes in a Tibetan alpine meadow during the growing season

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Research in Cold and Arid Regions 2017年第6期9卷 642-655页

作者： YiGang Hu ZhenHua Zhang ShiPing Wang ZhiShan Zhang Yang Zhao ZengRu Wang Shapotou Desert Experiment and Research Station Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of SciencesLanzhouGansu 730000China Key Laboratory of Adaptation and Evolution of Plateau Biota Northwest Institute of Plateau BiologyChinese Academy of SciencesXiningQinghai 810008China Key Laboratory of Alpine Ecology and Biodiversity Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100085China CAS Center for Excellence in Tibetan Plateau Earth Science Beijing 100101China

Fencing is the most common land-management practice to protect grassland degradation from livestock overgrazing on the Tibetan Plateau. However, it is unclear whether fencing reduces CO_2, CH_4, and N_2O emission. Here, we selected four vegetation types of alpine meadow(graminoid, shrub, forb, and sparse vegetation) to determine fencing effects on ecosystem respiration(Re), CH_4, and N_2O fluxes during the growing season. Despite increased average monthly ecosystem respiration(Re) for fenced graminoid vegetation at the end of the growing season, there was no significant difference between grazing and fencing across all vegetation types. Fencing significantly reduced average CH_4 uptake by about 50% in 2008 only for forb vegetation and increased average N_2O release for graminoid vegetation by 38% and 48% in 2008 and 2009,respectively. Temperature, moisture, total organic carbon, C/N, nitrate, ammonia, and/or bulk density of soil, as well as above-and belowground biomass, explained 19%~71% and 6%~33% of variation in daily and average Re and CH_4 fluxes across all vegetation types, while soil-bulk density explained 27% of variation in average N_2O fluxes. Stepwise regression showed that soil temperature and soil moisture controlled average Re, while soil moisture and bulk density controlled average CH_4 fluxes. These results indicate that abiotic factors control Re, CH_4, and N_2O fluxes; and grazing exclusion has little effect on reducing their emission—implying that climatic change rather than grazing may have a more important influence on the budgets of Re and CH_4 for the Tibetan alpine meadow during the growing season.

关键词： fencing ecosystem respiration methane nitrous oxide Tibetan alpine meadow

Yearning for That Piece of Green meadow

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中国翻译 1998年第6期 48-49页

ＩｔｗａｓａＦｅｂｒｕａｒｙｄａｙｉｎｅａｒｌｙｓｐｒｉｎｇｔｈａｔＩｇｏｔｔｏｋｎｏｗｔｈａｔｇｒｅｅｎｍｅａｄｏｗ．Ｅｖｅｒｙｔｈｉｎｇａｒｏｕｎｄｔｈｅｇｒｅｅｎｍｅａｄｏｗｗａｓｔｒａｎｑｕｉｌｗｈｅｎｉｔｄ... 详细信息

ＩｔｗａｓａＦｅｂｒｕａｒｙｄａｙｉｎｅａｒｌｙｓｐｒｉｎｇｔｈａｔＩｇｏｔｔｏｋｎｏｗｔｈａｔｇｒｅｅｎｍｅａｄｏｗ．Ｅｖｅｒｙｔｈｉｎｇａｒｏｕｎｄｔｈｅｇｒｅｅｎｍｅａｄｏｗｗａｓｔｒａｎｑｕｉｌｗｈｅｎｉｔｄｉｓｃｒｅｅｔｌｙ，ｗｉｔｈｙｏｕ...

关键词： That Yearning Piece Green meadow

THE IMPROVEMENT OF ALKALINE meadow BY ACCUMULATIVE SAND BY WIND IN THE SONGNEN PLAIN

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Chinese Geographical Science 1993年第2期3卷 65-68页

作者：李崇皓郑萱凤

In the Songnen Plain, there are 330,000 ha of alkaline meadow, many sand sources such as fixed dunes, semi-fixed dunes and sand hills, and rich wind force resources as well. Sand has been stopped naturally and A neurolepidium chinense has grown on alkaline patch of the plain. If we make use of the natural law and set up manmade obstacles in alkaline patches, we can use accumulative sand to cover alkali, improve alkaline meadow, restore A neurolepidium chinense vegetation to develop animal husbandry.

关键词： alkaline meadow accumulative sand improvement of alkaline meadow

Seasonal variations and mechanism for environmental control of NEE of CO_2 concerning the Potentilla fruticosa in alpine shrub meadow of Qinghai-Tibet Plateau

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Science China Earth Sciences 2006年第S2期49卷 174-185页

作者： LI Yingnian, SUN Xiaomin, ZHAO Xinquan, ZHAO Liang, XU Shixiao, GU Song, ZHANG Fawei & YU Guirui Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining 810001, China Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China Graduate University of Chinese Academy of Sciences, Beijing 100049, China

The study by the eddy covariance technique in the alpine shrub meadow of the Qing-hai-Tibet Plateau in 2003 and 2004 showed that the net ecosystem carbon dioxide exchange (NEE) exhibited noticeable diurnal and annual variations, with more distinct daily changes during the warmer seasons. The CO2 emission of the shrub ecosystem culminated in April and September while the CO2 absorption capacity reached a maximum in July and August. The absorbed carbon dioxide during the two consecutive years was 231.4 and 274.8 g CO2·m-2 respectively, yielding an average of 253.1 gCO2·m-2 per year: that accounts for a large proportion of absorbed CO2 in the region. Obviously, the diurnal carbon flux was negatively related to temperature, radiation and other atmospheric factors. Still, minute discrepancies in kurtosis and duration of carbon emission/absorption were detected between 2003 and 2004. It was found that the CO2 flux in the daytime was similarly affected by photosynthetic photon flux density in both years. Temperature appears to be the most important determinant of CO2 flux: specifically, the high temperature during the plant growing season inhibits the carbon absorption capacity. One potential explanation is that soil respiration is enhanced under such condition. Analysis of biomass revealed that the annual net carbon fixed capacity of aboveground and belowground biomass was 544.0 in 2003 and 559.4 g Cm"2 in 2004, which coincided with the NEE absorption capacity (63.1 g C·m-2 in 2003 and 74.9 g C·m-2 in 2004) in the corresponding plant growing season.

关键词： Potentilla frutlcosa shrub meadow yearly meteorological conditions CO2 exchange variations meteorolo

Peculiarities of Heavy Metals Accumulation by the Plants of meadow Phytocenosis

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Open Journal of Soil Science 2012年第3期2卷 275-281页

作者： Тatyana А. Trifonova Ekaterina Y. Alkhutova Faculty of Chemistry and Ecology Vladimir State Univer- sity Vladimir Russia Soil science department Lomonosov State University Moscow Russia

This work is devoted to studying of the accumulation peculiarities of heavy metals (HM) by the meadow phytocenosis plants and also plants phytomeliotating properties at various levels of soil contamination. The system “cespitose-podsol soil – meadow vegetation” has been chosen as a research object. Heavy metals as a kind of industrial waste-galvanic slurry enriched by zinc amounting 79.7% of all HM detected in the slurry-was introduced into the soil. Heavy metals content and redistribution in soil at various amount of galvanic slurry, quantitative and specific content of phytocenosis, heavy metals accumulation in the meadow vegetation crop at various contamination layers have been studied during research. Among the researched phytocenosis the groups of plants with high and low heavy metals accumulation capacity have been defined. Cirsium arvense, Capsella bursapastoris, Artemisia vulgarus and Rumex confertus belonged to the group accumulating several heavy metals in considerable amounts without significant phytomass loss. The majority of these plants possess developed phytomass and their ability to accumulate heavy metals in large amount allows using them as phytomeliorants for soil decontamination at the final stages of reclaiming.

关键词： Heavy Metals meadow Phytocenosis Plants Phytomeliotating Properties

Establishment of apparent quantum yield and maximum ecosystem assimilation on Tibetan Plateau alpine meadow ecosystem

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Science China Earth Sciences 2005年第Z1期48卷 141-147页

作者： XU Lingling, ZHANG Xianzhou, SHI Peili & YU Guirui Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China Graduate School of the Chinese Acedemy of Sciences, Beijing 100039, China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Graduate School of the Chinese Acedemy of Sciences Beijing 100039 China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

The alpine meadow is widely distributed on the Tibetan Plateau with an area of about 1.2×106kn2. Damxung County, located in the hinterland of the Tibetan Plateau, is the place covered with this typical vegetation. An open-path eddy covariance system was set up in Damxung rangeland station to measure the carbon flux of alpine meadow from July to October,2003. The continuous carbon flux data were used to analyze the relationship between net ecosystem carbon dioxide exchange (NEE) and photosynthetically active radiation (PAR), as well as the seasonal patterns of apparent quantum yield (α) and maximum ecosystem assimilation (Pmax).Results showed that the daytime NEE fitted fairly well with the PAR in a rectangular hyperbola function, with α declining in the order of peak growth period (0.0244 μmolCO2 · μmol-1pAR) ＞early growth period ＞ seed maturing period ＞ withering period (0.0098 μmolCO2 · μmol-1pAR).The Pmax did not change greatly during the first three periods, with an average of 0.433mgCO2· m-2· s-1, i.e. 9.829 μmolCO2· m-2· s-1. However, during the withering period, Pmax was only 0.35 mgCO2 · m-2 · s-1, i.e. 7.945 μmolCO2 · m-2 · s-1. Compared with other grassland ecosystems, the α of the Tibetan Plateau alpine meadow ecosystem was much lower.

关键词： Tibetan Plateau, alpine meadow ecosystem, eddy covariance, apparent quantum yield, maximum ecosystem assimilation.

Grassland ecology in China: perspectives and challenges

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Frontiers of Agricultural Science and Engineering 2018年第1期5卷 24-43页

作者： Deli WANG Ling WANG Jushan LIU Hui ZHU Zhiwei ZHONG Key Laboratory of Vegetation Ecology/Key Laboratory of Wetland Conservation and Restoration School of Environment/Institute of Grassland Science Northeast Normal University

During the last few decades, there have been an increasing number of studies on grassland ecology in China, involving the classic ecology concepts or theories and the applicable ecological principles of grassland conservation or management. This paper reviews the main progress in the following aspects.(1) Research on grassland species adaptation and resistance, population dynamics and foraging behavior, and biodiversity and community stability.(2) Research on managed grassland ecosystems(grassland grazing ecology) including grazing effects on grassland ecosystem function and foraging behavior by large herbivores.(3) Global climate change and grassland processes and functioning.(4) Applied research on grassland restoration and ecosystem health assessments such as vegetation restoration, restoration of ecosystem functioning, and assessment methods. There have been significant advances in grassland ecology,including the functions of ecosystem biodiversity, the ecological stoichiometry mechanisms affecting grassland community stability, grazing regulation of plant diversity and nutrient cycling. Grassland ecologists have succeeded in making these advances through observational, experimental and theoretical studies. Nevertheless, there are still significant challenges for the grassland ecology research,including understanding of grassland spatial processes,grassland grazing and multi-functionality, integrated effects of global climate change across grassland areas,as well as the ecological methodology and experimental techniques in grassland ecology.

关键词： biodiversity climate change China grazing meadow restoration steppe

Soil organic carbon storage and soil CO_2 flux in the alpine meadow ecosystem

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Science China Earth Sciences 2007年第7期50卷 1103-1114页

作者： TAO Zhen1,2,SHEN ChengDe2,GAO QuanZhou1,SUN YanMin2,YI WeiXi2 & LI YingNian3 1 School of Geography and Planning,Sun Yat-sen University,Guangzhou 510275,China 2 Guangzhou Institute of Geochemistry,Chinese Academy of Sciences,Guangzhou 510640,China 3 Northwest Plateau Institute of Biology,Chinese Academy of Sciences,Xining 810001,China School of Geography and Planning Sun Yat-sen University Guangzhou 510275 China Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China School of Geography and Planning Sun Yat-sen University Guangzhou 510275 China Northwest Plateau Institute of Biology Chinese Academy of Sciences Xining 810001 China

High-resolution sampling,measurements of organic carbon contents and 14C signatures of selected four soil profiles in the Haibei Station situated on the northeast Tibetan Plateau,and application of 14C tracing technology were conducted in an attempt to investigate the turnover times of soil organic car-bon and the soil-CO2 flux in the alpine meadow ecosystem. The results show that the organic carbon stored in the soils varies from 22.12×104 kg C hm-2 to 30.75×104 kg C hm-2 in the alpine meadow eco-systems,with an average of 26.86×104 kg C hm-2. Turnover times of organic carbon pools increase with depth from 45 a to 73 a in the surface soil horizon to hundreds of years or millennia or even longer at the deep soil horizons in the alpine meadow ecosystems. The soil-CO2 flux ranges from 103.24 g C m-2 a-1 to 254.93 gC m-2 a-1,with an average of 191.23 g C m-2 a-1. The CO2 efflux produced from microbial decomposition of organic matter varies from 73.3 g C m-2 a-1 to 181 g C m-2 a-1. More than 30% of total soil organic carbon resides in the active carbon pool and 72.8%―81.23% of total CO2 emitted from or-ganic matter decomposition results from the topsoil horizon (from 0 cm to 10 cm) for the Kobresia meadow. Responding to global warming,the storage,volume of flow and fate of the soil organic carbon in the alpine meadow ecosystem of the Tibetan Plateau will be changed,which needs further research.

关键词： Tibetan Plateau alpine meadow soil organic carbon CO2 flux 14C signature