Please wait a minute...
Table of Content
    Volume 42 Issue 1
    20 January 2018
    A warming experiment based on open-top chamber in a typical alpine steppe on the Qinghai-Tibetan Plateau, located in Sanjiaocheng Sheep Farm, Gangca County, Qinghai Province, China (Photographed by LI Fei). This special issue focuses on ecological processes in alpine ecosystems under changing environment.
      
    Ecological processes in alpine ecosystems under changing environment
    Yuan-He YANG
    Chin J Plan Ecolo. 2018, 42 (1):  1-5.  doi:10.17521/cjpe.2018.0048
    Abstract ( 849 )   HTML ( 93 )   PDF (1687KB) ( 1350 )   Save
    Figures and Tables | References | Related Articles | Metrics
    Research Articles
    CO2 flux dynamics and its limiting factors in the alpine shrub-meadow and steppe-meadow on the Qinghai-Xizang Plateau
    CHAI Xi, LI Ying-Nian, DUAN Cheng, ZHANG Tao, ZONG Ning, SHI Pei-Li, HE Yong-Tao, ZHANG Xian-Zhou
    Chin J Plant Ecol. 2018, 42 (1):  6-19.  doi:10.17521/cjpe.2017.0266
    Abstract ( 967 )   HTML ( 63 )   PDF (2476KB) ( 608 )   Save
    Figures and Tables | References | Related Articles | Metrics

    Aims Alpine shrub-meadows and steppe-meadows are the two dominant vegetation types on the Qinghai-Xizang Plateau, and plays an important role in regional carbon cycling. However, little is known about the temporal-spatial patterns and drivers of CO2 fluxes in these two ecosystem types.

    Methods Based on five years of consecutive eddy covariance measurements (2004-2008) in an eastern alpine shrub-meadow at Haibei and a hinterland alpine steppe-meadow at Damxung, we investigated the seasonal and annual variation of net ecosystem productivity (NEP) and its components, i.e. gross primary productivity (GPP) and ecosystem respiration (Re).

    Important findings The CO2 fluxes (NEP, GPP and Re) were larger in the shrub-meadow than in the steppe-meadow during the study period. The shrub-meadow functioned as a carbon sink through the five years, with the mean annual NEP of 70 g C·m -2·a -1. However, the steppe-meadow acted as a carbon neutral, with mean annual NEP of -5 g C·m -2·a -1. The CO2 fluxes of steppe-meadow exhibited large variability due to the inter-annual and seasonal variations in precipitation, ranging from a carbon sink (54 g C·m -2·a -1) in 2008 to a carbon source (-88 g C·m -2·a -1) in 2006. The differences in carbon budget between the two alpine ecosystems were firstly attributed to the discrepancy of normalized difference vegetation index (NDVI) because NDVI was the direct factor regulating the seasonal and inter-annual NEP. Secondly, the shrub-meadow had higher carbon use efficiency (CUE), which was substantially determined by annual precipitation (PPT) and NDVI. Our results also indicated that the environmental drivers of CO2 fluxes were also different between these two alpine ecosystems. The structure equation model analyses showed that air temperature (Ta) determined the seasonal variations of CO2 fluxes in the shrub-meadow, with NEP and GPP being positively correlated with Ta. By contrast, the seasonal CO2 fluxes in the steppe-meadow were primarily co-regulated by soil water content (SWC) and Ta, and increased with the increase of SWC and Ta. In addition, the changes of Re during the growing season in two ecosystems were directly affected by GPP and soil temperature at 5 cm depth (Ts), while Re during non-growing season were determined by Ts. These results demonstrate that the synergy of soil water and temperature played crucial roles in determining NEP and GPP of the two alpine meadows on the Qinghai-Xizang Plateau.

    Experimental warming changed plants’ phenological sequences of two dominant species in an alpine meadow, western of Sichuan
    ZHANG Li, WANG Gen-Xu, RAN Fei, PENG A-Hui, XIAO Yao, YANG Yang, YANG Yan
    Chin J Plan Ecolo. 2018, 42 (1):  20-27.  doi:10.17521/cjpe.2017.0133
    Abstract ( 544 )   HTML ( 32 )   PDF (1169KB) ( 571 )   Save
    Figures and Tables | References | Related Articles | Metrics

    Aims We studied phenological sequences of two dominant plants (Polygonum viviparum and Potentilla leuconota) in an alpine meadow of the Hengduan Mt., western of Sichuan to explore the alpine plants responses on climate change.

    Methods Open-top chambers (OTCs) chosen by ITEX were used to monitor the warming in the field. After a four-year experimental warming, in the 5th growing season we recorded the phenological sequences of two dominant species, focusing on plant responses on warming. The sequence was divided into four stages: budding, flowering, withering and ripe seeds. Each stage had three events: first, peak, and last.

    Important findings Our results showed that: 1) For P. viviparum, experimental warming elicited a shortening of the duration of each stage, advanced all of the phenological events but the first of withering and ripe seeds, shortened the period of each stage and reduced the duration of entire reproduction. 2) For P. leuconota, experimental warming extended the duration of every stage. All phenological events before the end of withering occurred earlier on experimental warming but the peak of flowering. The period of each stage had inconsistent responses on warming and warming prolonged the duration of entire reproduction. The present results indicated that not all phenological events were equally responsive to experimental warming and an entire sequence could be a more accurate way to evaluate the responses on environmental variation. Therefore, the plastic responses to warming of different species would have effects on community composition and structure.

    Effects of forest gap size on initial decomposition of twig litter in the subalpine forest of western Sichuan, China
    GUO Cai-Hong, YANG Wan-Qin, WU Fu-Zhong, XU Zhen-Feng, YUE Kai, NI Xiang-Yin, YUAN Ji, YANG Fan, TAN Bo
    Chin J Plan Ecolo. 2018, 42 (1):  28-37.  doi:10.17521/cjpe.2017.0186
    Abstract ( 383 )   HTML ( 24 )   PDF (2811KB) ( 656 )   Save
    Figures and Tables | References | Related Articles | Metrics

    Aims Existence of forest gaps affects soil moisture, temperature, and decomposer community structure in forest ecosystem; however, it remains largely unknown how the size of gaps affect litter decomposition. The objective of this study was to determine the rate of mass loss of twigs associated with the closed canopy and forest gaps of different sizes in a subalpine forest of western Sichuan, China.

    Methods Three forest gaps (FG1: 255-290 m 2, FG2: 153-176 m 2; FG3: 38-46 m 2) and three plots under a closed canopy in an alpine fir (Abies faxoniana) forest of western Sichuan, China were selected to conduct a litter decomposition experiment. The air-dried samples of A. faxoniana twigs were placed in nylon litterbags (size 20 cm × 20 cm, pore size 1.0 mm), and those litterbags were placed on the forest floor of experimental plots. The experiment was carried out for a period of four years from November 2012 to October 2016. Mass loss rates associated with different forest gaps and closed canopy were estimated every six months.

    Important findings Our results showed that there were significant differences in the depth of snow cover, the temperature and the frequency of freezing and thawing cycles on the forest floor associated with the three gaps and a closed canopy. The snow depth and the temperature were highest in the FG1 and lowest under the closed canopy. After four years, the remaining mass percentages of twig were 59.9%, 59.5%, 62.1% and 55.3% for the FG1, FG2, FG3 and the closed canopy, respectively. Correspondingly, the decomposition constant (k) was 0.127, 0.131, 0.120 and 0.135, and the time for 95% decomposition was 23.6, 22.7, 25.0 and 22.2 a for the FG1, FG2, FG3 and the closed canopy, respectively. Compared with the closed canopy, the mass loss rates in the forest gaps increased in the growing season for the first year and the second year, but reduced in the winter for the first year and fourth year. The effects of gap sizes on the mass loss rates varied with the decomposing periods. The mass loss rates increased with the increase of the gap size in the winter during the first year and the third year decomposing, and reduced with the increase of gap size in the growing season in the third year. Also, the percentage of mass loss was the highest in the first year and increased with the gap size. The percentage of mass loss in the winter was higher than that in the growing season. In conclusion, the formation of forest gaps profoundly affects the litter decomposition in the subalpine forest of western Sichuan.

    Effects of nitrogen addition on root dynamics in an alpine meadow, Northwestern Sichuan
    ZI Hong-Biao, CHEN Yan, HU Lei, WANG Chang-Ting
    Chin J Plan Ecolo. 2018, 42 (1):  38-49.  doi:10.17521/cjpe.2017.0255
    Abstract ( 502 )   HTML ( 22 )   PDF (4459KB) ( 1156 )   Save
    Figures and Tables | References | Related Articles | Metrics

    Aims Our aim was to characterize the effects of nitrogen (N) addition on plant root standing crop, production, mortality and turnover in an alpine meadow on the Northwestern plateau of Sichuan Province, China.

    Methods A N addition experiment was conducted in an alpine meadow on the Northwestern plateau of Sichuan Province since 2012. Urea was applied at four levels: 0, 10, 20 and 30 g·m -2·a -1, referred to as CK, N10, N20 and N30. Root samples in surface (0-10 cm) and subsurface layers (10-20 cm) were observed using Minirhizotron from May 10th to Sept. 27th in 2015. The root standing crop, production, mortality and turnover rate were estimated using WinRHZIO Tron MF software. Repeated-measure ANOVA, one-way ANOVA and Pearson correlation were performed to analyze the effect of N addition on soil and root characteristics.

    Important findings N addition significantly increased soil available N content and decreased soil pH value, but did not alter soil total N and SOM contents under all treatments. N addition did not exhibit any significant effects on the mean root standing crop and cumulative root production in the 0-10 cm, but significantly reduced mean root standing crop and cumulative root production in 10-20 cm soil layer by 195.3 and 142.3 g·m -2 (N10), 235.8 and 212.1 g·m -2 (N20) and 198.0 and 204.4 g·m -2(N30), respectively. The cumulative root mortality was significantly decreased by 206.1 g·m -2in N10 treatment and root turnover rate was significantly increased with 17% for N30 treatment at the 0-10 cm soil depth, but the cumulative root mortality and root turnover rate was not significantly different at 10-20 cm soil depth. In addition, cumulative root production, mortality and turnover rate in 0-10 cm soil layer were significantly correlated with the soil available N content, whereas no significant associations were observed in 10-20 cm soil. Taken together, these results demonstrate that N addition alters the soil N availability and thus induces the root dynamics and changes in root distribution as well as C allocation in alpine meadow.

    Nonlinear responses of productivity and diversity of alpine meadow communities to degradation
    CHEN Ning, ZHANG Yang-Jian, ZHU Jun-Tao, LI Jun-Xiang, LIU Yao-Jie, ZU Jia-Xing, CONG Nan, HUANG Ke, WANG Li
    Chin J Plan Ecolo. 2018, 42 (1):  50-65.  doi:10.17521/cjpe.2017.0252
    Abstract ( 581 )   HTML ( 46 )   PDF (1907KB) ( 1284 )   Save
    Figures and Tables | References | Related Articles | Metrics

    Aims The alpine meadow degradation could have profound effects on the grassland productivity. The aim of our study is to clarify the dynamic response of community productivity and species diversity in the process of alpine meadow degradation.

    Methods In the Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Northern Tibetan Grassland Ecosystem Research Station (Nagqu station), we conducted stages experiments with multiple degradation levels: control, mild degraded meadow, moderate degraded meadow, severe degraded meadow and serious sandy meadow.

    Important findings The response of aboveground biomass to alpine meadow degradation showed a linear or nonlinear increased response patterns, but the belowground biomass and total biomass decreased nonlinearly. As observed in measurement of aboveground biomass, Margalef index, Simpson index, Shannon-Wiener index and Pielou evenness index also exhibit a nonlinear increased response to degradation. The results of structural equation models showed that belowground biomass has a positive relationship with soil carbon content (p < 0.05) and volume water content (p < 0.1). However, soil nutrient and soil physical properties had no significant impact on aboveground biomass (p < 0.1). Compared with soil physical properties, soil nutrition is an important factor influencing the diversity index. In our study, the nonlinear responses of productivity and diversity of alpine meadow were described by using the multiple levels of degradation in space. The results suggested that aboveground productivity cannot interpret the degree of degradation of alpine meadow, and by contrast, alpine meadow degradation should be measured by the change of plant functional groups, such as edible grasses and poisonous forbs.

    Comparison of growth-climate relationship of Sabina przewalskii at different timberlines along a precipitation gradient in the northeast Qinghai-Xizang Plateau, China
    SONG Wen-Qi, ZHU Liang-Jun, ZHANG Xu, WANG Xiao-Chun, ZHANG Yuan-Dong
    Chin J Plan Ecolo. 2018, 42 (1):  66-77.  doi:10.17521/cjpe.2017.0251
    Abstract ( 675 )   HTML ( 18 )   PDF (1528KB) ( 1235 )   Save
    Figures and Tables | References | Related Articles | Metrics

    Aims To test the hypothesis that water is the main limiting factor of tree growth at the arid alpine timberline, and to explore the effects of water on growth-climate relationships of Sabina przewalskii along a precipitation gradient in the northeast Qinghai-Xizang Plateau.

    Methods Three sides were selected to sample the alpine timberline along a precipitation gradient in the northeast Qinghai-Xizang Plateau: Halihatu National Forest Park in Wulan County (HL, annual precipitation 217 mm), Qushigang in Dulan County (QS, 281 mm) and Hebei Forest Farm in Tongde County (HB, 470 mm). The correlation and response analysis at seasonal and extreme climate year scales were used to examine the spatial variations of the growth-climate relationship of S. przewalskii at different timberlines.

    Important findings Our results do not support the hypothesis that water is the main limiting factor of tree growth at the arid alpine timberline. The effect of precipitation on the radial growth of S. przewalskii were consistent across all three sampling sites, while the effects of temperature were different across sites. At HL site (low precipitation), the winter and summer minimum temperature were the main limiting factor of S. przewalskii radial growth, and this relationship did not significantly change in different extreme climate years. At QS site (middle precipitation), the radial growth of S. przewalskii was mainly limited by the minimum temperature in spring and summer, but its effect was weaker than that at low precipitation site. At HB site (high precipitation), the spring temperature had a significant negative effect on tree growth, and the positive effect of spring precipitation on tree growth was significantly enhanced in comparison with those at low and middle precipitation sites, especially in extreme high temperature and drought years. Summer precipitation did not significantly affect tree growth at high precipitation site. Our results did not support the hypothesis that the radial growth of trees at alpine timberline in arid/humid area is mainly limited by water/temperature. However, precipitation at timberline will affect the relationship between tree growth and temperature at different seasons. With the warming and humidification of the northeastern Qinghai-Xizang Plateau, the climatic limiting factors of tree growth in different timberline areas may be complicated.

    Hierarchical responses of plant stoichiometry to phosphorus addition in an alpine meadow community
    SUN Xiao-Mei, CHEN Jing-Jing, LI Jin-Xia, LI Liang, HAN Guo-Jun, CHEN Nian-Lai
    Chin J Plan Ecolo. 2018, 42 (1):  78-85.  doi:10.17521/cjpe.2017.0253
    Abstract ( 347 )   HTML ( 11 )   PDF (1262KB) ( 908 )   Save
    Figures and Tables | References | Related Articles | Metrics

    Aims Terrestrial carbon (C), nitrogen (N), phosphorus (P) stoichiometry will reflect the effects of adjustment to local growth conditions as well as species’ replacements. However, it remains unclear about the hierarchical responses of plant C:N:P to P addition at levels of species and functional groups in the N-limited alpine meadow.

    Methods A field experiment of P enrichment was conducted in an alpine meadow on the Qinghai-Xizang Plateau during 2009-2013. The stoichiometric patterns of four functional groups (grass, sedge, legume and forb) and five representative species, Elymus nutans (grass), Kobresia humilis (sedge), Oxytropis ochrocephala (legume), Taraxacum lugubre (rosette forb), Geranium pylzowianum (upright forb) were investigated in 2013, and the effects of P addition on species dominance and plant biomass were also analyzed.

    Important finding Both plant nutrition content and C:N:P varied significantly after five years’ P addition, and the responses were consistent at species- and functional group (exemplar species excluded)-levels in the alpine meadow. P addition had neutral effect on C concentrations of grasses, sedges and forbs at both species- and functional group (exemplar species excluded)-levels. P fertilization increased plant P concentrations and thus decreased C:P and N:P of the four functional groups (exemplar species excluded) and the corresponding species. N concentrations significantly decreased and C:N increased in grasses and sedges after P addition, and the species-level responses were consistent with the functional group (exemplar species excluded) level. P addition significantly increased N contents and decreased C:N in Oxytropis ochrocephala, but had neutral effect on N contents and C:N at the functional group (exemplar species excluded) level of the legumes. While N contents and C:N in forbs responded to P addition differently at species and functional group (exemplar species excluded) levels. In the N-limited alpine meadow, species dominance of grasses increased gradually after P addition due to the increased N and P use efficiencies, while the biomass proportion of forbs decreased because of the lowered nutrition use efficiency.

    Responses of soil inorganic nitrogen to increased temperature and plant removal during the growing season in a Sibiraea angustata scrub ecosystem of eastern Qinghai-Xizang Plateau
    MA Zhi-Liang, ZHAO Wen-Qiang, ZHAO Chun-Zhang, LIU Mei, ZHU Pan, LIU Qing
    Chin J Plan Ecolo. 2018, 42 (1):  86-94.  doi:10.17521/cjpe.2017.0086
    Abstract ( 489 )   HTML ( 21 )   PDF (1034KB) ( 494 )   Save
    Figures and Tables | References | Related Articles | Metrics

    Aims Little information has been available on the soil nitrogen transformation process of alpine scrubland under global warming and changing climate. This study aimed at clarifying seasonal dynamics of the soil nitrate and ammonium contents and their responses to increased temperature under different plant treatments.

    Methods We conducted a field experiment including two plant treatments (removal- or unremoval-plant) subjected to two temperature conditions (increased temperature or control) in Sibiraea angustata scrub ecosystem on the eastern Qinghai-Xizang Plateau. The contents of soil nitrate and ammonium were measured at the early, middle and late growing seasons.

    Important findings The results showed that soil nitrate and ammonium contents exhibited obvious seasonal dynamics. Throughout the entire growing season, the soil nitrate contents increased firstly and then decreased, while the soil ammonium contents increased continually. Particularly, in the early and middle growing season, the soil nitrate contents were significantly higher than those of ammonium, regardless of increased temperature and plant treatments; however, in the late growing season, the soil nitrate contents were significantly lower than those of ammonium. These results implied that soil nitrification was the major process of soil nitrogen transformation in the early and middle growing season; soil ammonification contributed mostly to soil nitrogen transformation in the late growing season. Furthermore, different responses of soil nitrate and ammonium contents to increased temperature and plant removal treatments were observed at the different stages in the growing season. The effects of increased temperature on soil nitrate contents mainly occurred in the middle and late growing season, but the effects varied with plant treatments. Increased temperature only significantly increased soil ammonium contents in the unremoval-plant plots during the middle growing season. The effects of plant treatments on soil nitrate contents only occurred in the control plots (controlled temperature). Plant removal only increased soil nitrate contents in the early and middle growing season, but significantly decreased soil nitrate contents in the late growing season. Plant removal significantly decreased soil ammonium contents in the increased temperature plots during the middle growing season. Probably, in the early and middle growing season, scrub vegetation mainly absorbed soil nitrate and the absorption process was not affected by increased temperature. These results would increase our understanding of the soil nitrogen cycling process in these alpine scrub ecosystems under global warming and changing climate.

    Responses of exchangeable base cations to continuously increasing nitrogen addition in alpine steppe: A case study of Stipa purpurea steppe
    QIN Shu-Qi, FANG Kai, WANG Guan-Qin, PENG Yun-Feng, ZHANG Dian-Ye, LI Fei, ZHOU Guo-Ying, YANG Yuan-He
    Chin J Plan Ecolo. 2018, 42 (1):  95-104.  doi:10.17521/cjpe.2017.0100
    Abstract ( 338 )   HTML ( 11 )   PDF (1266KB) ( 612 )   Save
    Figures and Tables | References | Related Articles | Metrics

    Aims Soil exchangeable base cations (BCs) play important roles in keeping soil nutrient and buffering soil acidification, which may be disturbed by anthropogenic nitrogen (N) input. Considering relatively limited evidence from alkaline soils, this study was designed to explore the effects of N addition on soil exchangeable BCs in a typical alpine steppe on the Qinghai-Xizang Plateau.

    Methods From May 2013, eight levels of N addition (0, 1, 2, 4, 8, 16, 24, 32 g·m -2·a -1) in the form of NH4NO3 were added in the alpine steppe, where soil is alkaline. During the following three years (2014-2016), we collected soil samples in mid-August in each year. By measuring the concentrations of exchangeable BCs, we examined their changes along the N addition gradient. We also explored the relationships between BCs and other plant and soil properties.

    Important findings Continuous N addition resulted in significant loss of exchangeable BCs, especially Mg 2+ in all three years and Na +in two years. The concentrations of BCs were found to be negatively related to above-ground biomass and the concentration of soil inorganic N (p < 0.05). These results indicated that increase in N availability stimulated plant growth, which in turn led to more uptake of BCs by plants. Moreover, enhanced NO3 - leaching resulted in the loss of BCs due to the charge balance in soil solution. In addition, increased NH4 + displaced BCs binding to soil surface and made them easy to be leached out of soils. Different from acid soils, soil acidification caused by N deposition in alkaline soils is mainly buffered by calcium carbonate, having less effect on BCs. Our results suggest that N addition results in the loss of exchangeable BCs in alkaline soils, leading to poor buffering capacity and decreased plant productivity over long time period, which needs to be considered during grassland management in the future.

    Responses of soil N2O emissions to experimental warming regulated by soil moisture in an alpine steppe
    WANG Guan-Qin, LI Fei, PENG Yun-Feng, CHEN Yong-Liang, HAN Tian-Feng, YANG Gui-Biao, LIU Li, ZHOU Guo-Ying, YANG Yuan-He
    Chin J Plan Ecolo. 2018, 42 (1):  105-115.  doi:10.17521/cjpe.2017.0164
    Abstract ( 380 )   HTML ( 17 )   PDF (1876KB) ( 493 )   Save
    Figures and Tables | References | Related Articles | Metrics

    Aims Nitrous oxide (N2O) is one of the most important greenhouse gases, which contributes a lot to global warming. However, considerable variations are observed in the responses of soil N2O emissions to experimental warming, and the underlying microbial processes remain unknown.

    Methods A warming experiment based on open-top chambers (OTCs) was set up in a typical alpine steppe on the Qinghai-Xizang Plateau. The static chamber combined gas chromatography method was applied to investigate soil N2O flux under control and warming treatments during the growing seasons in 2014 and 2015. Gene abundances of ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) were quantified using quantitative real-time PCR.

    Important findings Our results showed that the warming treatments increased soil temperature by 1.7 and 1.6 °C and decreased volumetric water content by 2.5% and 3.3% respectively during the growing season (May to October) in 2014 and 2015. However, there were no significant differences in other soil properties. Our results also revealed that, the magnitude of soil N2O emissions exhibited substantial variations between the two experimental years, which were 3.23 and 1.47 μg·m -2·h -1in 2014 and 2015, respectively, but no significant difference in N2O fluxes was observed between control and warming treatments. AOA and AOB abundances are 15.2 × 10 7and 10.0 × 10 5copies·g -1 in 2014, and 5.0 × 10 7and 4.7 × 10 5copies·g -1in 2015, with no significant differences between control and warming treatments during the experimental period. Furthermore, warming-induced changes in N2O emissions had no significant relationship with the changes in soil temperature, but showed a significant positive correlation with the changes in soil moisture at seasonal scale. Overall, these results demonstrate that soil moisture regulates the responses of N2O emissions to experimental warming, highlighting the necessity to consider the warming-induced drying effect when estimating the magnitude of N2O emissions under future climate warming.

    Effects of short-term experimental warming on soil microbes in a typical alpine steppe
    WANG Jun, WANG Guan-Qin, LI Fei, PENG Yun-Feng, YANG Gui-Biao, YU Jian-Chun, ZHOU Guo-Ying, YANG Yuan-He
    Chin J Plan Ecolo. 2018, 42 (1):  116-125.  doi:10.17521/cjpe.2017.0297
    Abstract ( 380 )   HTML ( 15 )   PDF (1207KB) ( 1056 )   Save
    Figures and Tables | References | Related Articles | Metrics

    Aims Soil microbe plays key role in mediating terrestrial carbon cycles. It has been suggested that climate warming may affect the microbial community, which may accelerate carbon release and induce a positive feedback to soil climate warming. However, there is still controversy on how microbial community responds to experimental warming, especially in cold and drought environment.

    Methods We conducted an open top chambers (OTCs) experiment to explore the effects of warming on soil microbial community in an alpine steppe on Qinghai-Xizang Plateau. During the maximum of the growing seasons (August) of 2015 and 2016, we monitored the biomass and structure of soil microbial community in warming and control plots using phospholipid fatty acids (PLFA) as biomarkers.

    Important findings Short-term warming treatment significantly increased the soil temperature by 1.6 and 1.6 oC and decreased soil moisture by 3.4% and 2.4% (volume fraction) respectively, but did not alter either soil properties or normalized difference vegetation index (NDVI) during the growing season (from May to October) in 2015 and 2016. During the maximum of growing seasons (August) of 2015 and 2016, the magnitude of microbial biomass carbon (MBC) were 749.0 and 844.3 mg·kg-1, microbial biomass nitrogen (MBN) were 43.1 and 102.1 mg·kg-1, and the microbial biomass C:N ranged between 17.9 and 8.4. Moreover, all three showed no significant differences between warming and control treatments. The abundance of bacteria was the most in microbial community, while arbuscular mycorrhizal fungi was the least, and warming treatment did not alter the abundance of different microbial group and the microbial community structure. Nonetheless, our result revealed that warming-induced changes in MBC had significant positive correlation with changes in soil temperature and soil moisture. These patterns indicate that, microbial community in this alpine steppe may not respond substantially to future climate warming due to the limitation of soil drought. Therefore, estimation of microbial community response to climate change calls for consideration on the combined effect of warming and drought.

    Effects of the spreading of Ligularia virgaurea on soil physicochemical property and microbial functional diversity
    SHI Guo-Xi, WANG Wen-Ying, JIANG Sheng-Jing, CHENG Gang, YAO Bu-Qing, FENG Hu-Yuan, ZHOU Hua-Kun
    Chin J Plan Ecolo. 2018, 42 (1):  126-132.  doi:10.17521/cjpe.2017.0111
    Abstract ( 571 )   HTML ( 9 )   PDF (1064KB) ( 1941 )   Save
    Figures and Tables | References | Related Articles | Metrics

    Aims Ligularia virgaurea is an indicator species of alpine meadow degradation. Recently, the vast spreading of L. virgaurea has brought the serious economic loss of grassland ecosystem, but it remains unclear whether soil microbes involve in the spreading of L. virgaurea.

    Methods We chose four patches with different density of L. virgaurea to measure the influence of spreading of L. virgaurea on the functional diversity of soil microbial community in the Qinghai-Xizang Plateau.

    Important findings The spreading of L. virgaurea increased soil microbial activity, but reduced soil available nitrogen concentration. The Shannon index, utilization number of carbon resource and evenness index of soil microbial community displayed no significant differences among patches, but the utilization structure of carbon resource in high density patch was significantly different from control patch. Our findings indicate that the limitation of soil nitrogen caused by the changing functional diversity of soil microbial community in the distributed sites is one of the mechanisms for the vast spreading of L. virgaurea in alpine meadow ecosystem.

    Characteristics of nutrients in two dominant plant species and rhizospheric soils in alpine desert of the Qinghai-Xizang Plateau under contrasting climates
    GOU Xiao-Lin, ZHOU Qing-Ping, CHEN You-Jun, WEI Xiao-Xing, TU Wei-Guo
    Chin J Plan Ecolo. 2018, 42 (1):  133-142.  doi:10.17521/cjpe.2017.0120
    Abstract ( 618 )   HTML ( 11 )   PDF (1182KB) ( 818 )   Save
    Figures and Tables | References | Related Articles | Metrics

    Aims This study was conducted to determine the responses of nutrients in plants and rhizospheric soils to climate in alpine-cold desert on the Qinghai-Xizang Plateau.

    Methods Tissue samples for two dominant plant species, Hippophae rhamnoides subsp. sinensis and Artemisia desertorum, and associated rhizospheric soil samples were collected from sites representing semi-arid and sub-humid climates in the alpine-cold desert on the Qinghai-Xizang Plateau. Measurements were made on the contents of carbon, nitrogen and phosphorus in roots and shoots, as well as on organic carbon, total nitrogen, total phosphate, ammonium nitrogen, nitrate nitrogen and available phosphate in rhizospheric soils in the 0-10 cm and 10-20 cm layer. The relationship between nutrients in plant tissues and rhizospheric soils and the influencing factors were analyzed.

    Important findings There were significant differences between the semi-arid and the sub-humid sites in tissue nutrients and rhizospheric soil nutrients for the two specie. Specifically, the contents of carbon, nitrogen, phosphorus in plant tissues differed significantly between the semi-arid and the sub-humid sites. Soil organic carbon, total nitrogen, ammonium nitrogen, nitrate nitrogen and available phosphate for the rhizosphere of A. desertorum were significantly higher on site under sub-humid climate than that under semi-arid climate; whereas the trend was reversed for the rhizosphere of H. rhamnoides subsp. sinensis. We found significant relationships between the tissue nutrients and soil nutrients, and significantly different plant nutrient ratios between the two species. There were negative correlations between tissues and rhizosheric soils in N:P ratio for A. desertorum and C:N ratio for H. rhamnoides subsp. sinensis under different climates.


  • WeChat Service: zwstxbfw

  • WeChat Public:zwstxb