狼针草光合特性对放牧干扰的响应

doi:10.3724/SP.J.1258.2013.00054

摘要/Abstract

摘要：

以内蒙古呼伦贝尔草甸草原围封草地和放牧草地为实验样地, 通过对两种草地类型中狼针草(Stipa baicalensis)的光合特性、水分关系、植物渗透调节等生理生态学特性测定分析, 比较研究放牧干扰对狼针草的影响。结果表明: 在放牧干扰下, 狼针草通过增强核酮糖二磷酸羧化酶(RUBPCase)活性、叶绿素含量、改变电子流的方向和速率、增强光系统II (PSII)活性(p < 0.05), 促进同化物的累积和植物的补偿生长, 应对放牧干扰的影响。放牧干扰下狼针草的光合速率日变化曲线呈单峰型, 而围封草地中呈“双峰型”, 出现“午休”现象, 正午RuBPCase的羧化能力下降是造成围封草地狼针草光合“午休”的非气孔因素之一, 而磷元素的缺失可能是导致二磷酸核酮糖羧化酶(Rubisco)活性下降的原因。在光合能量分配方面, 两种样地狼针草的PSII最大光化学量子产量(F_v/F_m)均出现光抑制现象。放牧草地中狼针草对光照增强较为敏感, F_v/F_m值下降趋势明显(p < 0.05)。和围封样地相比, 放牧样地的狼针草光化学猝灭(q_P)值升高, 而非光化学猝灭(NPQ)值降低(p < 0.05), 分配更多的能量于光合反应中心, 有利于同化物累积, 提高光合能力来适应放牧的影响。在放牧干扰下, 狼针草叶片水势与叶片含水量降低, 而渗透调节物质可溶性蛋白和可溶性糖含量增加(p < 0.05), 狼针草的蓄水性变弱, 需要通过增加体内渗透调节物质, 主动降低水势, 以保证从土壤中获取足够的水分维持自身生理活性。同时, 放牧干扰促进了狼针草对氮元素的吸收利用。放牧样地中狼针草光合氮、磷利用率均与叶比重呈负相关关系。

关键词: 荧光特性, 放牧干扰, 光合特性, 狼针草, 水分关系

Abstract:

Aims Our objective was to evaluate (a) the impact of livestock grazing disturbance on physiological traits of Stipa baicalensis and (b) the adaptive mechanisms that S. baicalensis employed.
Methods We investigated the diurnal variations of photosynthetic characteristics, water relations, light energy utilization, photosynthetic apparatus activity and osmotic regulation of S. baicalensis growing in both grazing and enclosed grassland of Hulun Buir, Inner Mongolia.
Important findings Both ribulose-1,5-bisphosphate carboxylase (RUBPCase) and chlorophyll content increased and the direction of electronic chain was altered with grazing, which is beneficial for S. baicalensis to cope with the impact of grazing disturbance by accumulating more assimilates. The midday depression of photosynthesis of S. baicalensis in the enclosed grassland resulted from the decline of RUBPCase carboxylation capacity, which is due to the absence of P. The photochemical quenching (q_P) of S. baicalensis in the grazed grassland is higher, which reflects that it tended to use more absorbed solar energy to improve photosynthetic capacity, which was adaptive to the effects of grazing. Lower leaf water content of S. baicalensis in the grazed field led to the increase of osmotic regulating substances for obtaining sufficient water from the soil. In addition, grazing disturbance promoted the absorption and utilization of N by S. baicalensis. Negative correlation of leaf mass per area (LAM) with photosynthetic nitrogen-use efficiency (PNUE) and photosynthetic phosphorus-use efficiency (PPNE) was observed in the S. baicalensis in both grasslands. Our research demonstrated that various ecophysiological mechanisms were employed by S. baicalensis as adaptive to grazing.

Key words: fluorescence characteristics, grazing disturbance, photosynthetic characteristics, Stipa baicalensis, water relation

晏欣,龚吉蕊,张梓瑜,黄永梅,安然,祁瑜,刘敏. 狼针草光合特性对放牧干扰的响应. 植物生态学报, 2013, 37(6): 530-541. DOI: 10.3724/SP.J.1258.2013.00054

YAN Xin,GONG Ji-Rui,ZHANG Zi-Yu,HUANG Yong-Mei,AN Ran,QI Yu,LIU Min. Responses of photosynthetic characteristics of Stipa baicalensis to grazing disturbance. Chinese Journal of Plant Ecology, 2013, 37(6): 530-541. DOI: 10.3724/SP.J.1258.2013.00054

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链接本文: https://www.plant-ecology.com/CN/10.3724/SP.J.1258.2013.00054

https://www.plant-ecology.com/CN/Y2013/V37/I6/530

图/表 10

表1 两种草地主要物种组成

Table 1 Main species composition of two grasslands

围封样地 Enclosed grassland	放牧样地 Grazing grassland
狼针草 Stipa baicalensis 羊草 Leymus chinensis 冷蒿 Artemisia frigida 柄状薹草 Carex pediformis 糙隐子草 Cleistogenes squarrosa 裂叶蒿 Artemisia tanacetifolia 草地早熟禾 Poa pratensis 阿尔泰狗娃花 Heteropappus altaicus	狼针草 Stipa baicalensis 羊草 Leymus chinensis 冷蒿 Artemisia frigida 宽叶薹草 Carex siderosticta 细叶白头翁 Pulsatilla turczaninovii 裂叶蒿 Artemisia tanacetifoli 长柱沙参 Adenophora stenanthina 柄状薹草 Carex pediformis

表2 两种样地植物群落分布(平均值±标准误差, n = 4)

Table 2 Plant community distribution of two grasslands (mean ± SE, n = 4)

样地 Field type	平均高度 Average height (cm)	生物量 Biomass (g)	盖度 Coverage (%)
围封样地 Enclosed grassland	26.92 ± 0.1	237.500 ± 0.09	81.65 ± 0.06
放牧样地 Grazing grassland	10.46 ± 0.1	99.962 ± 0.16	71.24 ± 0.02

图1 围封和放牧样地光合有效辐射(PAR)和大气温度的日变化(平均值±标准误差)。

Fig. 1 Diurnal variations of photosynthetically active radiation (PAR) and air temperature in enclosed and grazing grassland (mean ± SE).

表3 围封和放牧样地的土壤含水量(平均值±标准误差, n = 4)

Table 3 Soil water content of enclosed and grazing grassland (mean ± SE, n = 4)

土壤深度 Soil depth (cm)	围封样地 Enclosed grassland (%)	放牧样地 Grazing grassland (%)
0-10	34.09 ± 0.04	30.66 ± 0.02
10-20	29.10 ± 0.09	26.00 ± 0.12
20-30	23.01 ± 0.07	20.49 ± 0.10
30-40	21.99 ± 0.90	17.93 ± 0.20

图2 两种样地狼针草光合特性的日变化(平均值±标准误差)。

Fig. 2 Diurnal changes of photosynthetic characteristics of Stipa baicalensis in two grasslands (mean ± SE).

图3 两种样地狼针草叶绿素荧光参数的日变化(平均值±标准误差)。

Fig. 3 Diurnal changes of chlorophyll fluorescence parameters of Stipa baicalensis in two grasslands (mean ± SE).

图4 围封和放牧样地狼针草水分关系的日变化(平均值±标准误差)。

Fig. 4 Diurnal change of water relations of Stipa baicalensis in enclosed and grazing grassland (mean ± SE).

图5 两种样地狼针草叶绿素和可溶性糖与可溶性蛋白含量的日变化(平均值±标准误差)。

Fig. 5 Diurnal change of chlorophyll (Chl), soluble sugar and protein content of Stipa baicalensis in two grasslands (mean ± SE).

图6 两种样地狼针草核酮糖二磷酸羧化酶(RUBPCase)活性和电子传递速率(ETR)的日变化(平均值±标准误差)。

Fig. 6 Diurnal changes of ribulose bisphosphate carboxylase (RUBPCase) activity and electronic transport rate (ETR) of Stipa baicalensis in the two grasslands (mean ± SE).

图7 两种样地狼针草叶比重(LMA)、光合氮磷利用率(PNUE、PPUE)和叶片磷含量的日变化(平均值±标准误差)。

Fig. 7 Diurnal variations of leaf mass per area (LMA), photosynthetic nitrogen-use efficiency (PNUE), photosynthetic phosphorus-use efficiency (PPUE) and foliar P content of S. baicalensis in two grasslands (mean ± SE).

参考文献 47

[1]	Anderson JM (1986). Photo regulation of the composition, function, and structure of thylakoid membranes. Annual Review of Plant Physiology, 37, 93-136. DOI URL
[2]	Anderson TM, Dong Y, McNaughton SJ (2006). Nutrient acquisition and physiological responses of dominant Serengeti grasses to variation in soil texture and grazing. Journal of Ecology, 94, 1164-1175. DOI URL
[3]	Arnon D (1949). Copper enzymes in isolated chloroplasts, polyphenoloxidase in Beta vulgaris. Plant Physiology, 24, 1-25. DOI URL PMID
[4]	Asada K (1994). Production and action of active oxygen species in photosynthetic tissues. In: Foyer CH, Mullineaux PM eds. Causes of Photooxidative Stress and Amelioration of Defense Systems in Plants. CRC Press, Tokyo. 77-104.
[5]	Bieleski RL (1973). Phosphate pools, phosphate transport, and phosphate availability. Annual Review of Plant Physiology, 24, 225-252. DOI URL
[6]	Chen SP, Bai YF, Lin GH, Liang Y, Han XG (2005). Effects of grazing on photosynthetic characteristics of major steppe species in the Xilin River Basin, Inner Mongolia, China. Photosynthetica, 43, 559-565. DOI URL
[7]	Chen ZZ, Wang SP (2000). Typical Grassland Ecosystem of China. Science Press, Beijing. (in Chinese)
	[ 陈佐忠, 汪诗平 (2000). 中国典型草原生态系统. 科学出版社, 北京.]
[8]	Crofts AR, Baroli I, Kramer D, Taoka S (1993). Kinetics of electron transfer between QA and QB in wild type and herbicide-resistant mutants of Chlamydomonas reinhardtii. Z Naturforsch, 48, 259-266.
[9]	Demmig B, Björkman O (1987). Comparison of the effect of excessive light on chlorophyll fluorescence (77K) and photon yield of O₂ evolution in leaves of higher plants. Planta, 171, 171-184. DOI URL PMID
[10]	Demmig-Adams B, Adams WW III, Barker DH, Logan BA, Bowling DR, Verhoeven AS (1996). Using chlorophyll fluorescence to assess the fraction of absorbed light allocated to thermal dissipation of excess excitation. Physiologia Plantarum, 98, 253-264. DOI URL
[11]	Elser JJ, Marzolf ER, Goldman CR (1990). Phosphorus and nitrogen limitation of phytoplankton growth in the freshwaters of North America: a review and critique of experimental enrichments. Canadian Journal of Fisheries and Aquatic Sciences, 47, 146-1477.
[12]	Epron D, Godard D, Cornic G, Genty B (1995). Limitation of net CO₂ assimilation rate by internal resistance to CO₂ transfer in the leaves of two tree species (Fagus sylvation L. and Castanea sativa Mill.). Plant, Cell & Environment, 18, 43-51.
[13]	Evans JR (1983). Nitrogen and photosynthesis in the flagleaf of wheat (Triticum aestivum L.). Plant Physiology, 72, 297-302. DOI URL PMID
[14]	Evans JR, Seemann JR (1984). Differences between wheat genotypes in specific activity of ribulose-1, 5 bisphos- phate carboxylase and the relationship to photosynthesis. Plant Physiology, 74, 759-765. DOI URL PMID
[15]	Farquhar GD, Sharkey TD (1982). Stomach conductance and photosynthesis. Annual Review of Plant Physiology, 33, 317-345. DOI URL
[16]	Farquhar GD, von Caemmerer S, Berry JA (1980). A biochemical model of photosynthetic CO₂ assimilation in leaves of C₃ species. Planta, 149, 78-90. DOI URL PMID
[17]	Filella I, Llusià J, Piñol J, Peñuelas J (1998). Leaf gas exchange and fluorescence of Phillyrea latifolia, Pistacia lentiscus and Quercus ilex saplings in severe drought and high temperature conditions. Environmental and Experimental Botany, 39, 213-220. DOI URL
[18]	Groat RG, Vance CP (1981). Root nodule enzymes of ammonia assimilation in alfalfa (Medicago sativa L). Plant Physiology, 67, 1198-1203. DOI URL
[19]	Hikosaka K (2004). Interspecific difference in the photosynthesis-nitrogen relationship: patterns, physiological causes, and ecological importance. Journal of Plant Research, 117, 481-494. DOI URL
[20]	Kedrowski RA (1983). Extraction and analysis of nitrogen, phosphorus and carbon fractions in plant material. Journal of Plant Nutrition, 6, 989-1011. DOI URL
[21]	Krall JP, Edward GE (1992). Relationship between photosystem II activity and CO₂ fixation in leaves. Physiologia Plantarum, 86, 180-187. DOI URL
[22]	Kramer PJ (1998). Water Relations of Plants. Academic Press, New York.
[23]	Laisk A, Loreto F (1996). Determining photosynthetic parameters from leaf CO₂ exchange and chlorophyll fluorescence. Plant Physiology, 110, 903-912. DOI URL PMID
[24]	Larcher W (1994). Ökophysiologie der Pflanzen. Verlag Eugen Ulmer, Stuttgart. 47-100.
[25]	Li HS (1999). Plant Physiological Biochemical Experiment Principles and Techniques. Higher Education Press, Beijing. 131-261. (in Chinese)
	[ 李合生 (1999). 植物生理生化实验原理和技术. 高等教育出版社, 北京. 131-261.]
[26]	Liang EY, Wang YF, Xu Y, Liu B, Shao XM (2010). Growth variation in Abies georgei var. smithii along altitudinal gradients in the Sygera Mountains, southeastern Tibetan. Plateau Trees, 24, 363-373.
[27]	Lin ZF, Peng CL (2000). The allocation of photosynthetic electron transport and absorbed light energy in leaves of four woody plants acclimated to different light intensities. Acta Phytophysiologica Sinica, 26, 387-392. (in Chinese with English abstract)
	[ 林植芳, 彭长连 (2000). 4种木本植物叶片的光合电子传递和吸收光能分配特性对光强的适应. 植物生理学报, 26, 387-392.]
[28]	Makhnev AK, Makhneva NE (2010). Landscape-ecological and population aspects of the strategy of restoration of disturbed lands. Contemporary Problems of Ecology, 3, 318-322. DOI URL
[29]	Marschner H (1995). Mineral Nutrition of Higher Plants. 2nd edn. Academic Press, London, UK.
[30]	Melis A, Harvey GW (1981). Regulation of photosystem stoichiometry, chlorophyll a and chlorophyll b content and relation to chloroplast ultrastructure. Biochimica et Biophysica Acta-Bioenergetics, 63, 138-145.
[31]	Meyer GA (1998). Mechanisms promoting recovery from defoliation in goldenrod (Solidago altissima). Canadian Journal of Botany, 76, 450-459. DOI URL
[32]	Onoda HK, Hirose T, Hirose T (2004). Allocation of nitrogen to cell walls decreases photosynthetic nitrogen-use efficiency. Functional Ecology, 18, 419-425. DOI URL
[33]	Parkhurst DF (1994). Diffusion of CO₂ and other gases inside leaves. New Phytologist, 126, 449-479. DOI URL
[34]	Peng Y, Jiang GM, Liu XH, Niu SL, Liu MZ, Biswas DK (2007). Photosynthesis, transpiration and water use efficiency of four plant species with grazing intensities in Hunshandak Sandland, China. Journal of Arid Environments, 70, 304-315. DOI URL
[35]	Poorter H, Evans JR (1998). Photosynthetic nitrogen-use efficiency of species that differ inherently in specific leaf area. Oecologia, 116, 126-137.
[36]	Racker E (1962). Ribulose diphosphate carboxylase from spinach leaves. In: Colowick SP, Kaplan NO eds. Methods in Enzymology. Academic Press, New York. 266-278.
[37]	Richards JH (1993). Physiology of plants recovering from defoliation. In: Proceedings of the XVII International Grasslands Conference. Polmerston North, New Zealand. 47-55.
[38]	Sukenik A, Bennett J, Falkowski P (1987). Light-saturated photosynthesis-limitation by electron transport or carbon fixation. Biochimica et Biophysica Acta-Bioenergetics, 2, 205-215.
[39]	Sun W, Resco V, Williams DG (2010). Nocturnal and seasonal patterns of carbon isotope composition of leaf dark- respired carbon dioxide differ among dominant species in a semiarid savanna. Oecologia, 164, 297-310. URL PMID
[40]	Takashhna T, Kkosaka K, Hirose T (2004). Photosynthesis or persistence: nitrogen allocation in leaves of evergreen and deciduous Quercus species. Plant, Cell & Environment, 27, 1047-1054.
[41]	Vu JC, Allon LH, Gowes G (1987). Drought stress and elevated CO₂ effects on soybean ridulose bisphosphate carboxylase activity and canopy photosynthetic rates. Plant Physiology, 83, 573-578. DOI URL PMID
[42]	Xue S, Wang PH (1992). Effects of water stress of CO₂ assimilation of two winter wheat cultivars with different drought resistance. Acta Phytophysiol Sinica, 18, 1-7. (in Chinese with English abstract)
[43]	Ye JY, Mi HL (1999). Experimental Guide of Modern Plant Physiology. Science Press, Beijing. 108-109. (in Chinese)
	[ 叶济宇, 米华玲 (1999). 现代植物生理学实验指南. 科学出版社, 北京. 108-109.]
[44]	Zhao P, Sun GC, Peng SL (1998). Ecophysiological research on nitrogen nutrition of plant. Ecologic Science, 17, 37-42. (in Chinese with English abstract)
	[ 赵平, 孙谷畴, 彭少麟 (1998). 植物氮素营养的生理生态学研究. 生态科学, 17, 37-42.]
[45]	Zhao W, Chen SP, Han XG, Lin GH (2009). Effects of long-term grazing on the morphological and functional traits of Leymus chinensis in the semiarid grassland of Inner Mongolia, China. Ecological Research, 24, 99-108. DOI URL
[46]	Zhou G, Wang Y, Wang S (2002). Responses of grassland ecosystems to precipitation and land use along the Northeast China Transect. Journal of Vegetation Science, 13, 361-368. DOI URL
[47]	Zou Q (2000). The Experiment Guide of Plant Physiology. China Agricultural Press, Beijing. 80-82, 137-138, 119-120. (in Chinese)
	[ 邹琦 (2000). 植物生理学实验指导. 中国农业科技出版社, 北京. 80-82, 137-138, 119-120.]