September 1997, Volume 39 Issue 9


          Research Articles
Experiment and Modelling on the Responses of Chinese Terrestrial Ecosystems to Global Change
Author: Zhou Guang- sheng, Zhang Xin-shi, Gao Su-hua, Bai Ke-zhi, Yan Xiao-dong and Zheng Yuan-run
Journal of Integrative Plant Biology 1997 39(9)
    It is the important objective of the core project "Global Change and Terrestrial Ecosystems (GCTE)" of International Geosphere-Biosphere Project (IGBP) to predict the feedback of terrestrial ecosystems on atmosphere and climate and the responses of the structure and function of ecosystems, natural and managed, to global change in finer scales. A lot of achievements in scientific research have been made, since Chinese scientists took part in the "Global Change Study" in 1985. The comment on the mechanism of responses of natural and managed ecosystems in China to doubled CO2 concentration and climatic change, modeling responses of Chinese terrestrial ecosystems to global change, possible effects of global clinkatic change on China' s desertification, and the study on Northeast China Transect (NECT) made recently by Chinese scientists will be presented. The interplan study should draw more attention in the future, and some important tasks will also be pmposed.
Abstract (Browse 1856)  |  Full Text PDF       
Effects of Doubled CO2 Concentration on the Content of Photosynthetic Pigments and PS II Functions of Jointing and Grouting in Setaria italica
Author: Lu Cong-ming, Zhang Qi-de, Feng Li-jie, Kuang Ting-yun, Guo Jian-ping and Wang Chun-yi
Journal of Integrative Plant Biology 1997 39(9)
    Effects of doubled CO2 on the contents of chlorophyll and carotenoid per unit fresh weight and per unit area of leaves and PS functions of Setaria italica (L.) Beauv. were studied. The experimental results showed that the contents of chlorophyll and carotenoid, the proportion of opened PS reaction center from the mature leaves at jointing stage and the mature flag leaves at grouting stage were raised with CO2 enrichment. However, qN value and the overall photochemical quantum yield of PS , as well as the Fv/Fo, Fv/Fro and Fd/Fs in the above-mentioned leaves both at the jointing and grouting stage in response to doubled CO2 were different. The final outcome showed that the photosynthetic functions from the leaves at jointing stage improved by doubled CO2 were better than those from the flag leaves at grouting stage.
Abstract (Browse 1804)  |  Full Text PDF       
Effect of Doubled CO2 Concentration on Leaf Chlorophyll-protein Complexes in Several Plants
Author: Wang Ke-bin, Lou Shi-qing, Zhao Fu-hong, Dai Yun-ling and Kuang Ting-yun
Journal of Integrative Plant Biology 1997 39(9)
    The effect of doubled CO2 on the chlorophyll-protein complexes of the leaves of soybean ( Glycine max L., Ca plants), cucumber ( Cucumis sativus L., C3 plant), millet ( Setaria italica (L.) Beauv., not a very typical C4 plant) and corn (Zea mays L. ,C4 plant) was studied. Experi- mental plants were pot-cultured in polyethylene membrane (or glass) open top cultured chambers. After sowing, C02 was kept immediately either at ambient ( (350 10) x 10-6) concentration for the control or at doubled CO2 ((700 10) x 10-6) concentration for the treatment chambers. The chlorophyll-protein complexes of the thylakoid membrane of the plants were resolved by disk SDS- PAGE. The results showed that after doubled CO2 treatment,either in the soybean and cucmnber,or in the millet, the quantity of polymer state of PS light-harvesting chlorophyll a/b-protein complex (LHC ) had increased as the monomer state of LHC decreased. But such response to doubled CO2 was not found in corn, the C4 plant. The change of the state of LHC in soybean etc. might be an adaptive effect of plant photosynthetic mechanism to the long term elevated CO2. Thus it could increase the efficiency of the absorption, transfer and conversion of light energy in plant photosynthesis, and support the high efficiency of photosynthetic carbon assimilation.
Abstract (Browse 1790)  |  Full Text PDF       
Effect of CO2 Concentration Doubling on the Leaf Morphology and Structure of 10 Species in Gramineae
Author: Yang Song-tao, Li Yan-fang, Hu Yu-xi and Lin Jin-xing
Journal of Integrative Plant Biology 1997 39(9)
    The effects of CO2 concentration on leaf thickness, chloroplast manbers in the bundle sheath cell, epidermal cell density, stomatal density, stomatal index, stomatal size were compared in 10 species in Gramineae: Triticum aestivum L., T. aestivum ssp. tibeticum, Hordeum vulgare L., H. brevisubulatum ( Trin. ) Link, Oryza sativa L., O. meyeriana ssp. granulata, Setaria italica (L.) Beauv, S. viridis (L.) Beauv, Sorghum vulgare Pers., Zea mays L. following their exposure to doubled carbon dioxide (700L/L) and ambient carbon dioxide concentration (350L/L). The results indicated that different species of plants might vary in their response to doubled CO2. In general, the leaves became thicker under the elevated CO2 condition. The mean stomatal density of the C3 species was decreased in doubled CO2, whereas the results of C4 species showed an inverse trend. The epidermal cell density and the chloroplast numbers of the bundle sheath cell in the wild plant species were less than those in the control under CO2 enrichment. The stomatal density was positively correlated with the stomatal index. Finally, the general pattern of structural variation under different CO2 concentrations was proposed, and their implication to the research of global change was discussed as well.
Abstract (Browse 1870)  |  Full Text PDF       
Effect of Elevated CO2 Concentration on the Starch Grain Accumulation in Chloroplasts from Soybean Leaves at Different Nodes
Author: Zuo Bao-yu, Jiang Gui-zhen, Zhang Quan, Bai Ke-zhi and Kuang Ting-yun
Journal of Integrative Plant Biology 1997 39(9)
    Soybean ( Glycine max (L.) Merr. ) plants were grown under ambient and elevated CO2 (plus 350 L/L) concentration in cylindrical open-top chamber to examine their effects on the ultra- structure of chloroplasts. The upper, lower and mid-node leaves were harvested after 7 days full expansion under different CO2 concentrations and ultrathin section were prepared for transmission electron microscopy. In general, the average content of starch grains and thylakoid membranes in the chloroplasts under the elevated CO2 concentration were always higher than the control. Under higher CO2 concentration, there were smaller and less starch grains in the chloroplasts from upper-node leaves than those from mid-node leaves. The shape of their starch grains changed from elliptical to oval,and their thylakoid membranes and grana remained normal. At lower-node leaves, one or two oval, or three timer starch grains accumulated in the chloroplasts. In the mid-node leaves,however, some chloroplasts under higher CO2 concentration had rather large tim elliptical starch grains which could consequently cause disruption of grana and stroama thylakoids in the chloroplasts, whereas in other chloroplasts, the thylakoid membranes and grana were not deformed as the starch grains were smaller and elliptical. On the other hand, under higher CO2 concentration, the stacking degree of thylakoid membranes and starch grains accumulation in the mid-node leaves were significantly higher than those in the lower-node leaves,and slightly higher than the upper-node leaves. These results, in agreement with the chlorophyll contents and photosynthetic rate which reported by other authors in the past, indicated that the ultrastmcture response of the chloroplasts from different leaf nodes of soybeen under elevated CO2 coneentration were different. The seed yield of soybean at different nodes was decreased gradually from mid-nodes towards both upper- and lower-nodes. The greatest effect of elevated CO2 eoneentrafion on seed yeild was at the mid-node leaves. The variation of seed yields of soybean at different nodes under elevated CO2 concentration was in eoneert with the change in the ultrastmcture of chloroplasts and in turn the change in their photosynthetic rates of leaves at different nodes.
Abstract (Browse 2013)  |  Full Text PDF       
Responses of Plant Dark Respiration to Doubled CO2 Concentration
Author: Wang Xing-fen, Bai Ke-zhi and Kuang Ting-yun
Journal of Integrative Plant Biology 1997 39(9)
    Ten species of plants were grown at ambient (350mol CO2mol-1 air) and doubled (700 mol CO2mol-1 air) CO2 concentrations at ambient temperature and illumination in order to examine changes of dark respiration of whole seedlings or detached leaves. Effects of CO2 on dark respiration were determined by brief exposure ( 5 min) to corresponding CO2 concentration and temperatures ( 15,20,25,30 and 35 ) with infrared CO2 analyzer. The reductions in dark respiration on a weight base for leaves of East-Liaoning oak (Quercus liaotungensis Koidz. ) at 15,20 and 25 and of soybean ( Glycine max L. ) at 20,25,30 and 35 and for whole seedlings of three- tcoloured amaranth (Amaranthus tricolor L. ) at 15 and 20 and cucumber ( Cucumis sativus L. ) at 15 cE measured at elevated concentration relative to the ambient CO2 concentration were observed. No significant difference in respiration responded was observed to elevated or ambient CO2 concentrations at 15 in maize (Zea mays L. ) seedlings and alfalfa (Medicago sativa L. ) leaves, at 35 in East-Liaoning oak leaves and at 20,25 and 30 in three-coloured amaranth seedlings. However CO2 efflux in leaves of weeping willow (Salix babylonica L. ), simon poplar (Populus simonii Carr. ) and eucommia (Eucommia ulmoides Oliv. ) at 15,20,25,30 and 35 , alfalfa at 20,25,30 and 35 , East-Liaoning oak at 30 , maize at 15 , seedlings of common buckwheat (Fagotrytum esculentum Moench) at 15,20,25,30 and 35 , cucumber and maize at 20,25,30 and 35 and three-coloured amaranth at 35 showed an increase at elevated in contrast to ambient CO2 concentration. In general, at lower temperatures (i. e. 15, 20 ) there was no significant difference between elevated and ambient CO2 concentration for dark respiration, while at higher temperatures (i. e. 30,35 ) elevated CO2 concentration positively stimulate clark respiretion. It has not yet been described that double CO2 concentration could enhance plant dark respiration at 30 and 35 . Impacts of the characteristics in dark respiration on the future changes of vegetation and its mechanism were discussed.
Abstract (Browse 2040)  |  Full Text PDF       
Effects of Doubled CO2 Concentration on Light Energy Absorption and Excitation Energy Distribution Between PS II and PS I in Chloroplasts of Weeping Willow and Eucommia
Author: Zhang Qi-de, Lu Cong-ming, Liu Li-na, Feng Li-jie and Kuang Ting-yun
Journal of Integrative Plant Biology 1997 39(9)
    Under CO2 doubling, the content of chlorophyll and carotenoid per unit fresh weight and er unit area of leaves from weeping willow ( Salix babylonica L. ) as well as chlorophyll of eucommia ( Eucommia ulmoides Oliv. ) were raised, but carotenoid content of eucommia was reduced. The capability of light energy absorption of chloroplasts and regulative capability of excitation energy distribution between PS and PS were also raised by doubled CO2 condition.
Abstract (Browse 1817)  |  Full Text PDF       
Sensitivity of Terrestrial Ecosystem to Global Change in China
Author: Zheng Yuan-run, Zhou Guang-sheng, Zhang Xin-shi, Yang Dian-an and Xia Li
Journal of Integrative Plant Biology 1997 39(9)
    Assessment of the sensitivity of natural and agricultural vegetation in China to global change based on the natural vegetation net primary productivity (NPP) model and the agricultural vegetation NPP model had revealed a decreasing trend from the southeast to the northwest in a ribbon shaped distribution for the terrestrial ecosystem NPP, where the center of low NPP was formed in Xinjiang area under all possible conditions of climate change. In China the productivity of the ter- restrial ecosystem would increase by 1 to 2 t DW hm-2 a-l in moist area where the temperature in- creased by 2 with no change of precipitation. It would increase by 0.5 to 3.0 t DW hm-2 a-l especially in arid and semiarid areas where the temperature increased by 2 and precipitation in- creased by 20%; and would increase by 0.5 to 1.0 t DW hm-2 a-1 in moist area, decreased 0.5 to 2.0 t DW hm-2 a-1 in arid and semiarid areas especially in the arid area where the temperature increased by 2 and precipitation decreased by 20%. The results indicated that water was a key factor to terrestrial ecosystem in China.
Abstract (Browse 1779)  |  Full Text PDF       
An Agricultural Net Primary Productivity Model
Author: Zheng Yuan-run, Zhou Guang-sheng, Zhang Xin-shi, Wang Jian-lin and Tai Hua-jie
Journal of Integrative Plant Biology 1997 39(9)
    A net primary productivity (NPP) model of agricultural vegetation was presented based on the ecophysiological feature of plants and climatic factors: NPP=exp(rRn(r2+Rn2+rRn)/(Rn+r)(Rn2+r2)•(0.0015RDI+0.0013) This model was used to simulate the NPP of agricultural vegetation according to the comparison between the observed agricultural NPP data from 27 provinces and cities and the simulated data, which were in good agreement. The sensitivity study of agricultural vegetation was also done with the new NPP model in China. The results showed that the crop productivity would increase by 0.44 % to 12. 88 % in China when the temperature inereased by 2 and precipitation unchanged or increased by 20%. It would increase by 5.46% to 12.88% in moist area when precipitation change and inereased by 4.15% to 10.92% in arid and semiarid areas when precipitation inereased by 20%; and it would increase by 1.48 % to 14.63 % in moist area, decrease by 0.44 % to 6.01% in arid and semiarid areas especially in arid area when the temperature increased by 2 and precipitation decreased by 20%. This indicated that water was a key factor to agrieuhural vegetation. The new NPP model would help us to understand and forecast agricultural development, to organize agricultural activity effectively, to make good use of agricultural resources, and to increase lands capacity.
Abstract (Browse 1807)  |  Full Text PDF       
Monitoring the Ecological Transect in East Asia Monsoon Region by Meteorological Satellite Remote Sensing
Author: Xiao Qian-guang, Chen Wei-ying, Du Peng and Guo Liang
Journal of Integrative Plant Biology 1997 39(9)
    The results of monitoring the ecological transect in East Asia monsoon region by normalized difference vegetation index (NDVI) indicated the presence of a close relationship between the NDVI of each ecological belt and the advance and retreat of the East Asia monsoon. There is a normal NDVI distribution in the normal monsoon year and an abnormal NDVI distribution in the abnormal monsoon year. Through the study of the regularity of NDVI variation of such main ecological belts in the transect as desert grassland, dry grassland, steppe, cultivated land and forest, the authors found that the NDVI variation could be considered as a measure to evaluate the characteristics of annual monsoon climate change.
Abstract (Browse 2013)  |  Full Text PDF       
A Remote Sensing Model for Determining Chlorophyll Content and Its Distribution Using Landsat Images
Author: Zhang Ren-hua, Sun Xiao-min and Zhu Zhi-lin
Journal of Integrative Plant Biology 1997 39(9)
    The uncertainty in the estimatation of chlorophyll content with the use of normalized difference vegetation index (NDVI) has been described. To determine the chlorophyll content, model 1 for LANDSAT and model 2 for NOAA AVHRR wavebands were presented and have been verified by field experiments. Model 1 was also validated by the distribution of chlorophyll content using LANDSAT images around the Yucheng remote sensing experimental station. Using these models to estimate the chlorophyll content in the vegetation community is benefitiated by the increased precision and decreased uncertainty.
Abstract (Browse 1876)  |  Full Text PDF       
An Ecophysiological Model for Individual Plant Under Global Change
Author: Yu Mei, Gao Qiong and Gao Su-hua
Journal of Integrative Plant Biology 1997 39(9)
    Plant growth is affected by atmospheric CO2 concentration in two ways. On one hand, CO2, as a substrate of assimilation, has a direct effect on plant physiological process, such as photosynthesis, respiration, transpiration and so on. On the other hand, as a green house gas, the variation of CO2 concentration can induce climatic change, which can indirectly influence plant growth. In the last decade, a large body of studies were done on the direct effects of CO2 increasing on plant growth. However, only a few of them considered the combined effects of increased CO2 and climatic change on plant growth. Since it is very difficult to experiment with both the direct and indirect effects of CO2, using a simulation model, if not the only way, is a very important approach in the global change study. The authors presented first a stochastic weather generator in which stochastic simulation was applied to produce the daily or hourly time series of the weather factors, such as temperamm'precipitation'relative humidity,etc. The monthly data of 1951 to 1980 and daily data of 1981 to 1983 from Beijing Meteorological Station were used to parameterize and validate the weather generator. The results showed that the simulated series conformed to the observed ones very well. The second part of this work was the establishment of a plant ecophysiological model at leaf scale. The model consisted of a mechanistic leaf photosynthesis model, a stomatal conductance model, a transpiration model and a model of water use efficiency (WUE). On the basis of results obtained from an experiment in which C3 plant soybean (Glycine max (L.) Merr. ) was grown in an open-top chamber with both ambient (350 mol mol- 1 ) and doubled (700 MMOLmol- 1 ) CO2 concentrations, the key parameters were estimated by fitting the model to the measured data using nonlinear regression. The predicted values of photosynthesis, stomatal conductance, transpiration and WUE by the model were shown to be in close agreement with observations. Parameter analyses showed that the quantum efficiency, a, was significantly increased by CO2 enrichment while the CO2 conductance coefficient, , was slightly decreased by elevated CO2. When temperature and soil water content were not limiting factors for plant growth, the prediction by the model showed that the net photosynthesis rate would increase by about 45 %, stomatal conductance decrease by 30%, transpiration rate reduce by 30%, and water use efficiency increase by 100% ,as CO2 concentration doubled from 350 mol mol-1 to 700 molmo1-1.
Abstract (Browse 1739)  |  Full Text PDF       
Dynamic Modelling of Northeast China Transect Responses to Global Change-A Regional Vegetation Model Driven by Remote Sensing Information
Author: Gao Qiong, Yu Mei, Zhang Xin-shi and Guan Feng
Journal of Integrative Plant Biology 1997 39(9)
    A remote sensing driven dynamic simulation model was developed for terrestrial ecosystems. The model was encoded in C language under the environment of SPAMOD, a spatial simulation tool developed under MS Windows. The model was applied to Northeast China Transect to simulate the dynamics of green and non-green biomass of 12 vegetation categories as well as soil water of 3 layers. The green biomass was converted to normalized difference vegetation index (NDVI) of AVHRR remote sensing, and compared with the observed NDVI from 1986 to 1990. The model was also compared with ground measurements of biomass and productivity along the transect. Ambient CO2 concentration, monthly mean air temperature and monthly precipitation were regarded as the three basic driving variables for global change study. The model also included the effects of temperature and precipitation on sunshine fracti6n, relative humidity, radiation, soil water and eventually plant growth. For each CO2 and climatic scenario, the model was run for an equilibrium solution. The results indicated that the natural vegetation of the transect was very sensitive to variation of temperature and CO2 concentration. With CO2 remained unchanged and temperature increased by 4 CE, the induced increase in evapotranspiration could reduce the average biomass and net primary productivity (NPP) over the whole transect by 32.1% and 41.9 % respectively. In contrast, a 20 % increase in precipitation alone could lead to an increase of the average biomass and NPP by 8.1% and 13.4% respectively. Under the present climatic conditions, CO2 doubling could increase the average biomass and NPP by 12.2% and 17.1% respectively. Because of compensation between the positive effects of CO2 and precipitation increase and the negative effect of temperature increase, a comprehensive interaction among CO2 doubling, a 20% increase of precipitation and a 4 increase of temperature altogether can lead to approximately a 2% reduction in the biomass and NPP of the natural vegetation over the whole transect.
Abstract (Browse 1868)  |  Full Text PDF       
A Gradient Analysis and Prediction on the Northeast China Transect (NECT) for Global Change Study
Author: Zhang Xin-shi, Gao Qiong, Yang Dian-an, Zhou Guang-sheng, Ni Jian and Wang Quan
Journal of Integrative Plant Biology 1997 39(9)
    The terrestrial transect has already become an important approach and hot spot for International Geosphere-Biosphere Progran (IGBP) in the global change study. Northeast China Transect (NECT) is listed as one of the first set of IGBP transect. It is placed along the latitude 43˚30' N, between longtitudes 112˚ and 130˚30' E, and approximately 1 600 km in length. NECT is basically a gradient driven by precipitation/moisture factors located in the mid-latitude of the temperate zone. The vegetation zones or biomes along the NECT consist of temperate mixed evergreen coniferous and broadleaf deciduous forest and temperate steppe, including three subzones, viz. meadow steppe, typical steppe, and desert steppe, along an east-westward continuous transitional spatial seties, respectively. There are four ecological experimental stations with support from a great number of permanent samples and long-tenn experimental data on the transect. The initial gradient analysis and simulation for the predicted scenario under increasing temperature given for the transect included the geographical location, significance of setup, topography, geomorphology, Climate, soil, vegetation and pattern of land use. One remote sensing driven model and one NPP model have been tested and operated for the whole transect. The study on NECT will be enhanced by research project, concerning biogeochemical cycles (water, C, N, P, etc, and CO2, CH4 greenhousegas emisson), structure, function and dynamics of ecosystems, land use and land coverage, biodiversity, dynamic globalvegetation modeling (DGVM), and high resolution remote sensing data. It will become a frontier for the studies of Global Change and Terrestrial Ecosystems (GCTE) and other IGBP core projects in China.
Abstract (Browse 1961)  |  Full Text PDF       
Monitoring Inter-annual Variation of Evapotranspiration with Meteorological Satellite Remote Sensing Method in China Monsoon Transect
Author: Guo Liang, Du Peng, Xiao Qian-guang and Chen Wei-ying
Journal of Integrative Plant Biology 1997 39(9)
    The balance and exchange of water and energy in the ecosystem of China is noticeably affected by the monsoon climate especially associated with the occurrence of flood and drought in summer time. The determination of evapotranspiration (Ep), an important parameter of water balance, thus, is a linchpin for the investigation of monsoon-its mechanism and practical impacts. A new method to obtain actual Ep value has leen developed, which could monitor the actual Ep value in macro scale by using NOAA/AVHRR satallite data. The principle of the method is based on the experiment carried out by NASA in the eighth decade. In the IGBP( International Geosphere-Bio- sphere Program) studies, 13 special areas were selected for accessing their bio-diversity and the sensitiveness of climate change. NECT (Northeast China Transect) is one of the three mid-scale study areas. The location is 43.5˚ 1.5˚ N and 112˚ to 130.5˚ E. There are several biological systems including desert, dry grassland, steppe, forest and cultivated land. The vegetation index, as one of the significant indices of great importance in remote sensing, provides abundant and objective information for regional and global eco-environmental monitoring. NDVI (normalized difference vegetation index) is the most widely used vegetation index due to its efficiency, and is defined as: NDVI = ( CH2- CH1 )/( CH2 + CH1 ), where, CHI, CH2 are the albedo of channel 1 and channel 2 respectively. Some studies showed that NDVI is closely related to water supply conditions and Ep is one of the signs of water supply conditions as known, so some of our experiments was carried out to find the relation between Ep and NDVI in NECT. The experimental model of Ep is shown as following: E = ae bNDVI, where, a and b are the empirical coefficients. NDVI data of NECT specified in the years of 1990, 1991 and 1992 were selected in this study. The results are highlighted as follows: 1. The climate condition was normal in 1990; precipitation was abnormally high in 1991 as floods occurred in many places of China and droughts occurred in 1992 due to poor precipitation. The climate features of those years could be seen in the Ep map. For example, the area with Ep values from 0 to 250 mm was the smallest in 1991 and biggest in 1992, indicating that Ep reflects climate changes directly. 2. The Ep of China exhibited ribbon-like distribution, with much more prominent variation from west to east than from north to south. By analyzing the Ep in three lines (42N, 44N, 45N) of the transect, it was found that there was quite a similar trend of change in the lines from 200 mm to 800 nun or more. The distribution of the biological systems from the west to the east was as in the order of desert, dry grassland, steppe, dry grassland, cultivated land and forest. The patterns of Ep distribution were in agreement with the distribution of vegetation species in this area especially in the west of the transect. 3. Analysis of the inter-annual variation of Ep among the years of 1990, 1991 and 1992 revealed that one could deduct from the maximum variation (the absolute value) that, under a specific condition of climate change, the most significant response appeared to be at the boundaries between the dry grassland and the steppe where the vegetation population was very frangible and very sensitive to the slightest climate change. The result may be helpful in selecting a target area for further research on the effect and mechanism of monsoon climate.
Abstract (Browse 1759)  |  Full Text PDF       
Editorial Office, Journal of Integrative Plant Biology, Institute of Botany, CAS
No. 20 Nanxincun, Xiangshan, Beijing 100093, China
Tel: +86 10 6283 6133 Fax: +86 10 8259 2636 E-mail:

Copyright © 2018 by the Institute of Botany, the Chinese Academy of Sciences
Online ISSN: 1744-7909 Print ISSN: 1672-9072 CN: 11-5067/Q