模拟牦牛和藏羊践踏与降水对矮生嵩草根系营养物质含量的影响
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摘要
在高山草甸进行模拟牦牛和藏羊践踏与降水双因子调控试验,探究矮生嵩草根系营养物质含量对模拟牦牛和藏羊践踏强度与降水的响应。结果发现,随着模拟践踏强度(牦牛和藏羊)的增加,矮生嵩草根系还原糖、可溶性蛋白、可溶性糖、淀粉及粗蛋白质含量均呈先升后降趋势。在相同践踏强度下,随着模拟降水量的下降,矮生嵩草根系可溶性糖、可溶性蛋白、还原糖、淀粉和粗蛋白质含量均呈下降趋势。3个水分处理下,牦牛和藏羊中度践踏下矮生嵩草根系物质含量(可溶性糖、可溶性蛋白、还原糖、淀粉和粗蛋白质)均显著高于对照(P<0.05)。丰水处理下,牦牛和藏羊践踏下矮生嵩草根系营养物质含量均显著高于同等践踏强度下少雨处理(P<0.05)。丰水和缺水处理下,牦牛中度践踏下矮生嵩草根系可溶性糖和可溶性蛋白含量显著高于藏羊中度践踏处理。少雨、平水和丰水处理下,藏羊重度践踏处理下根系还原糖、淀粉和粗蛋白质含量均显著高于牦牛重度践踏处理(P<0.05)。模拟践踏和降水共同作用对矮生嵩草根系可溶性糖、可溶性蛋白、还原糖、淀粉和粗蛋白质的影响均达极显著水平。综合可得,适度的牦牛和藏羊践踏有利于根系营养物质的积累,少雨和重度践踏会抑制根系营养物质的积累。
In order to providing a basis for the reasonable management and utilization of alpine meadow,the effects of trampling of yak and Tibetan sheep and rainfall on nutrients content in Kobresia humilis root were studied with a two factors(simulated trampling and rainfall)controlled experiment in Tianzhu alpine meadow.The results showed that the content of reducing sugar,soluble protein,soluble sugar,starch and crude protein increased firstly then decreased with increasing yak and Tibetan sheep trampling intensity.Each index showed the trend of decline under the same intensity with simulated precipitation decreasing.Under the three rainfall treatment(lower,average and high level of rainfall),the starch content(reducing sugar,soluble protein,soluble sugar,starch and crude protein)of K.humilis under the moderate trampling of yaks and Tibetan sheep was significantly higher than that of CK(P<0.05).Contrary to the treatment of higher rainfall,the content of the root matter under yak and Tibetan sheep same trample intensity was significantly decreased under the lower rainfall(P<0.05).Under the treatment of lower and higher rainfall,the content of soluble sugar and soluble protein in the K.humilis root under yak moderate trampling was significantly higher than that under the Tibetan sheep moderate trampling.Under the three rainfall treatment(lower,average and high level of rainfall),the contents of reducing sugar,starch and crude protein under the Tibetan sheep heavy trampling intensity was significant higher than yak heavy trampling intensity(P<0.05).The interaction between simulated rainfall and simulated trampling had significant effect on reducing sugar,soluble protein,soluble sugar,starch and crude protein of K.humilis.Moderate yak and Tibetan sheep trampling are beneficial to the accumulation of K.humilis root nutritive material,and contrary to the lower rainfall and heavy trampling intensity.
In order to providing a basis for the reasonable management and utilization of alpine meadow,the effects of trampling of yak and Tibetan sheep and rainfall on nutrients content in Kobresia humilis root were studied with a two factors(simulated trampling and rainfall)controlled experiment in Tianzhu alpine meadow.The results showed that the content of reducing sugar,soluble protein,soluble sugar,starch and crude protein increased firstly then decreased with increasing yak and Tibetan sheep trampling intensity.Each index showed the trend of decline under the same intensity with simulated precipitation decreasing.Under the three rainfall treatment(lower,average and high level of rainfall),the starch content(reducing sugar,soluble protein,soluble sugar,starch and crude protein)of K.humilis under the moderate trampling of yaks and Tibetan sheep was significantly higher than that of CK(P<0.05).Contrary to the treatment of higher rainfall,the content of the root matter under yak and Tibetan sheep same trample intensity was significantly decreased under the lower rainfall(P<0.05).Under the treatment of lower and higher rainfall,the content of soluble sugar and soluble protein in the K.humilis root under yak moderate trampling was significantly higher than that under the Tibetan sheep moderate trampling.Under the three rainfall treatment(lower,average and high level of rainfall),the contents of reducing sugar,starch and crude protein under the Tibetan sheep heavy trampling intensity was significant higher than yak heavy trampling intensity(P<0.05).The interaction between simulated rainfall and simulated trampling had significant effect on reducing sugar,soluble protein,soluble sugar,starch and crude protein of K.humilis.Moderate yak and Tibetan sheep trampling are beneficial to the accumulation of K.humilis root nutritive material,and contrary to the lower rainfall and heavy trampling intensity.
引文
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[2] Sang T K Vo,Johnson E A.Alpine plant life:functional plant ecology of high mountain ecosystems[J].Mountain Research and Development,2001,21(2):202.
[3]柴锦隆,徐长林,杨海磊,等.模拟践踏和降水对高寒草甸土壤物理特性和微生物数量的影响[J].草业学报,2017,26(2):30-42.Chai Jinlong,Xu Changlin,Yang Hailei,et al.Effects of simulated and rainfall on soil physical properties and microorganism abundance in a alpine meadow[J].Acta Prataculturae Sinica,2017,26(2):30-42.
[4]刘玉,常小峰,田福平,等.放牧对草地群落与土壤特征的影响[J].西北植物学报,2016,36(12):2524-2532.Liu Yu,Chang Xiaofeng,Tian Fuping,et al.Effects of grazing on community and soil characteristics in the semi-arid grassland[J].Acta Bot.Boreal.-Occident.Sin.,2016,36(12):2524-2532.
[5] Schleuss P M,Heitkamp F,Sun Y,et al.Nitrogen uptake in an alpine Kobresia pasture on the Tibetan plateau:localization by 15 N labeling and implications for a vulnerable ecosystem[J].Ecosystems,2015,18(6):946-957.
[6]侯扶江,任继周.甘肃马鹿冬季放牧践踏作用及其对土壤理化性质影响的评价[J].生态学报,2003,23(3):486-495.Hou Fujiang,Ren Jizhou.Evaluation on trampling of grazed Gansu wapiti(Cervus elaphus kansuensis Pocock)and its effects on soil property in winter grazing land[J].Acta Ecologica Sinica,2003,23(3):486-495.
[7] Adler P B,Hall S A.The development of forage production and utilization gradients around livestock watering points[J].Landscape Ecology,2005,20(3):319-333.
[8]李小娟,李以康.青藏高原高寒草甸退化对矮嵩草有关生理特性的影响[J].西北植物学报,2017,37(8):1577-1585.Li Xiaojuan,Li Yikang.Effests of Tibetan plateau meadow degradation on the physiological characteristics of Kobresia humilis[J].Acta Bot.Boreal.-Occident.Sin.,2017,37(8):1577-1585.
[9]杨苹,程智敏,陈叙生,等.土壤水分调控对烤烟根系、植株形态及生理特性的影响[J].贵州农业科学,2017,45(9):21-23.Yang Ping,Cheng Zhimin,Chen Xusheng,et al.Effects of soil moisture regulation on flue-cured tobacco root system plant morphology and physiological characteristics[J].Guizhou Agricultural Sciences,2017,45(9):21-23.
[10]杨柳青,刘浩然,孙国伟,等.干旱胁迫对不同抗旱大豆品种生理特性及生长参数的影响[J].中国农业科技导报,2016,18(2):115-120.Yang Liuqing,Liu Haoran,Sun Guowei,et al.Effects of drought stress on physiological property and growth parameter of different drought resistance soybean cultivars[J].Journal of Agricultural Science and Technology,2016,18(2):115-120.
[11]杨树晶,郑群英,干友民,等.不同放牧强度下草地植物生理变化的研究[J].草业与畜牧,2016(3):1-4.Yang Shujing,Zheng Qunying,Gan Youmin,et al.The study on grassland vegetation physiological responed to different grazing intensities[J].Prataculture&Animal Husbandry,2016(3):1-4.
[12]塔娜,王海,赵山志.放牧绵羊对恢复阶段退化草场营养物质含量的影响[J].中国草地学报,2011,33(2):44-50.Ta Na,Wang Hai,Zhao Shanzhi.Effects of grazing sheep on forage nutrition contents in recovering degraded grassland[J].Chinese Journal of Grassland,2011,33(2):44-50.
[13]运向军,卫智军,吕世杰,等.荒漠草原不同利用条件下短花针茅贮藏性碳水化合物的对比[J].中国草地学报,2012,34(6):89-94.Yun Xiangjun,Wei Zhijun,LüShijie,et al.Comparative study of the storage carbohydretes in Stipa breviflora on desert steppe under different utilization[J].Chinese Journal of Grassland,2012,34(6):89-94.
[14]徐长林.高寒牧区不同燕麦品种生长特性比较研究[J].草业学报,2012,21(2):280-285.Xu Changlin.A study on growth characteristics of different cultivars of oat(Avena sativa)in alpine region[J].Acta Praculturae Sinica,2012,21(2):280-285.
[15]苗福泓.青藏高原东北缘草地植物群落对放牧利用强度和降水变异的响应[D].兰州:兰州大学,2015.Miao Fuhong.Response of plant community to stocking rate and precipitation variation in the grassland of northeast edge of Qinghai-Tibetan plateau[D].Lanzhou:Lanzhou University,2015.
[16]齐高先,钱莉,汪作成.天祝县近60年气候变化分析[J].安徽农业科学,2014,42(16):5255-5257.Qi Gaoxian,Qian Li,Wang Zuocheng.Analysis of climate change in recent 60years in Tianzhu county[J].Journal of Anhui Agricultural Sciences,2014,42(16):5255-5257.
[17]杨海磊.天祝高寒草甸牦牛和藏羊蹄压与践踏强度的研究[D].兰州:甘肃农业大学,2016.Yang Hailei.Study on the hoof pressure and trampling intensity of yaks and Tibet sheep in Tianzhu alpine meadow[D].Lanzhou:Gansu Agricultural University,2016.
[18]邹琦.植物生理学实验指导[M].第2版.北京:中国农业出版社,2000:110-129.Zou Qi.Plant physiology experiment guide[M].Second edition.Beijing:China Agriculture Press,2000:110-129.
[19]石文宏,宛涛,蔡萍,等.乌丹蒿幼苗对干旱胁迫的生理响应[J].中国草地学报,2018,40(1):115-120.Shi Wenhong,Wan Tao,Cai Ping,et al.Physiological responses of Artemisis wudanica seedlings to drought stress[J].Chinese Journal of Grassland,2018,40(1):115-120.
[20]王彦萍,刘王锁.不同放牧强度对荒漠草原植物根系生理变化的影响[J].江西畜牧兽医杂志,2016,34(2):25-30.Wang Yanping,Liu Wangsuo.Effects of different grazing intensities on the physiological changes of plant roots in desert steppe[J].Jiangxi Animal Husbandry and Veterinary Magazine,2016,34(2):25-30.
[21]马红彬.不同放牧强度对荒漠草原几种牧草一些生理指标的影响[J].干旱地区农业研究,2008,26(2):79-84.Ma Hongbin.Influence of different grazing intensities in desert steppe on some physiological indexes of several pastures[J].Agricultural Research in the Arid Areas,2008,26(2):79-84.
[22] Oran C H.Changes in the carbohydrate reserves of ladino white clover following defloliation[J].Plant Physio.,1952,28:467-474.
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