羊草和牧冰草旱作条件下的牧草产量分析

对中国产羊草和引自美国的牧冰草共７份材料／品种在内蒙古半干旱地区旱作条件下进行了牧草产量试验,试验结果指出：在建植２～６年期间,所有供试材料的牧草产量年际变幅都比较大,但羊草的变异系数相对低于牧冰草,牧草产量的年际变化受４～７月降水量和牧草生长年限的双重影响,但建植４～５年以后则主要受生长年限的影响。就牧草产量平均值和稳产性而言,羊草ＬＥＣＨ－ＩＭＣ最好,牧冰草Ｗａｌｓｈ最差,牧冰草Ａｒｒｉｂａ,     

羊草和牧冰草旱作条件下的牧草产量分析

对中国产羊草和引自美国的牧冰草共7份材料/品种在内蒙古半干旱地区旱作条件下进行了牧草产量试验.试验结果指出,在建植2～6年期间,所有供试材料的牧草产量年际变幅都比较大,但羊草的变异系数相对低于牧冰草.牧草产量的年际变化受4～7月降水量和牧草生长年限的双重影响,但建植4～5年以后则主要受生长年限的影响.就牧草产量平均值和稳产性而言,羊草LECH-IMC最好,牧冰草Walsh最差;牧冰草Arriba、Barton、Rodan和Rosana对内蒙古半干旱地区的草地补播有利用潜力.     

八种根茎类禾草种子耐盐性研究

对盐胁迫下对8种根茎类禾草种子萌发进行了研究,结果表明:种子相对发芽率、相对发芽指数、相对活力指数和相对电导率在不同浓度间有差异,但因种而异,不同种间有显著差异;在牧草种子阶段进行耐盐性评价时,可以选择以下几个指标:发芽率、活力指数、电导率、耐盐适宜范围和耐盐半致死浓度;盐胁迫对牧草种子萌发速度、幼苗生长势的影响大于对萌发能力的影响;供试牧草耐盐性由强到弱的顺序为:克拉克中间薄冰草>焦斯长穗薄冰草>中间薄冰草>埃克长穗薄冰草>茹莎那牧冰草>羊草>赖草>巴顿牧冰草。     

西方牧冰草和羊草在内蒙古西部草原的建植试验

西方牧冰草５个品种和羊草在内蒙古西部地区旱作条件下的植水平均受播种当年降水条件的影响，干旱年份播种，幼苗存活率低，建植水平差，降水量接近或高于平年年份播种，西方牧冰草和羊草均可获得较好的建植效果，其中西方牧冰草品种Ｒｏｓａｎａ和Ａｒｒｉｂａ显著优于当地羊草。     

中美耐盐禾草建植和产量试验

对选自中国和美国的28份多年生耐盐禾草在内蒙古河套灌溉区盐渍荒地上进行的建植和产量试验结果表明,在表土含盐量为0.54%～0.72%、pH值为8.9～9.4的盐渍土中,引自美国的高薄冰草品种Tyrell、Jose、Largo、Alkar和中国的野大麦生长良好,建植率为57%～80%,干草产量为4700～6900kg/hm2;美国的阿尔泰赖草Prairieland、卡氏赖草Logon's、细披碱草Pryor、San Luis、西方牧冰草Rosana、Barton、Arriba、杂交偃麦草RS-Hoffman、RST-hybrid以及中国的羊草LECH2等品种/材料也可建植成功,并获得较高的牧草产量.     

几各豆科牧草旱作条件下的牧草产量分析

对选自中国和美国的１２份豆科牧草材料／品种在内蒙古干旱和半干旱地区旱作条件下进行了牧草产量试验的和分析。来源于内蒙古当地的豆科牧草产量显著优于引自北美的供试品种。在干旱地区,直立黄芪、扁蓿豆、达乌里胡枝子和牛枝子适应性较好,其中直立黄芪牧草产量最高。在半干旱地区,沙打旺牧草产量最高,但稳产性低于扁蓿豆和达乌里胡枝子,来源于北美的供试材料在内蒙古干旱地区不能收获牧草,在半干旱地区降水丰年播种可收获一     

典型草原打草场主要牧草生产特性、 营养成分及饲用价值评价

以典型草原5种主要牧草羊草(Leymus chinensis)、大针茅(Stipa grandis)、达乌里胡子枝(Lespedeza davurica)、扁穗冰草(Agropyron cristatum)和中华隐子草(Cleistogenes chinensis)为研究对象,通过饲料常规营养成分的检测分析和牧草品质评定预测公式对其生产特性、营养成分及饲用价值进行综合分析比较。结果表明:大针茅的产量最高,为235.06 kg/hm2,牧草营养成分高低排序为:扁穗冰草大针茅中华隐子草羊草达乌里胡枝子,饲用价值高低排序为:扁穗冰草大针茅羊草中华隐子草达乌里胡枝子。结合牧草的实际生产产量,综合评价5种牧草的利用价值及质量品质为:扁穗冰草大针茅中华隐子草羊草达乌里胡枝子。本研究可以为该地区典型草原主要牧草在家畜营养中的应用提供合理的参考依据。     

豆科牧草与禾本科牧草混合青贮饲喂肉羊试验研究

试验通过不同比例豆科与禾本科牧草混合青贮试验,从感官、营养配比等指标确定豆科牧草(苜蓿、红豆草)和禾本科牧草(玉米秸秆、燕麦)的适宜混合青贮比例,并结合育肥肉羊的饲喂对比试验,评价其饲喂效果。结果表明:豆科牧草含量在25%~60%范围内均能成功制作青贮饲料;苜蓿混合青贮饲料粗蛋白和钙含量高于同比例红豆草组合;随豆科牧草比例增加,混合青贮饲料粗蛋白和钙含量增大;豆科牧草与带穗玉米混合青贮饲料无氮浸出物含量高于同比例去穗玉米或燕麦组合;带穗玉米与40%的紫花苜蓿或红豆草混合青贮,可显著提高育肥肉羊日增重,优于同比例去穗玉米混合青贮料。     

几种豆科牧草旱作条件下的牧草产量分析

对选自中国和美国的12份豆科牧草材料/品种在内蒙古干旱和半干旱地区旱作条件下进行了牧草产量试验和分析.来源于内蒙古当地的豆科牧草产量显著优于引自北美的供试品种.在干旱地区,直立黄芪、扁蓿豆、达乌里胡枝子和牛枝子适应性较好,其中直立黄芪牧草产量最高.在半干旱地区,沙打旺牧草产量最高,但稳产性低于扁蓿豆和达乌里胡枝子.来源于北美的供试材料在内蒙古干旱地区不能收获牧草,在半干旱地区降水丰年播种可收获一定产量.生长季降水量和牧草的生长年限对牧草产量的年际变化有重要影响,影响程度因牧草种性及其生境不同而异.     

不同牧草在肉羊瘤胃中的降解特性研究

研究旨在评估不同牧草干物质（DM）和粗蛋白（CP）在反刍动物瘤胃内的降解特性。以3只安装永久性瘤胃瘘管的陶赛特肉羊为试验动物,对常见的6种牧草的瘤胃降解特性进行分析。结果显示：苜蓿的DM和CP瘤胃实时降解率显著高于其他牧草（P<0.05）,羊草的DM和CP瘤胃实时降解率最低。不同牧草的DM有效降解率排序为：苜蓿>沙打旺>燕麦草>狗尾草>象草>羊草,CP有效降解率排序为：苜蓿>沙打旺>象草=燕麦草>狗尾草>羊草。研究表明,豆科牧草苜蓿和沙打旺在瘤胃中的降解率高于禾本科牧草象草、燕麦草、狗尾草和羊草。     

不同放牧强度对荒漠草原牧草微量元素和营养成分的影响

[目的]探明不同放牧强度下荒漠草原牧草和主要优势牧草的微量元素和营养成分含量的变化特征.[方法]在内蒙古自治区鄂尔多斯市鄂托克旗荒漠草原不同放牧强度区域(适度放牧区、禁牧区和重度放牧区)进行连续3年野外调查和室内检测,综合分析不同放牧强度对荒漠草原牧草以及优势牧草微量元素和营养成分含量的影响.[结果]适度放牧区优势牧草...     

CNCPS评定毛乌素沙地荒漠化草原区常见牧草营养价值的研究

为了更好地评估毛乌素沙地荒漠化草原区常见牧草的整体营养水平,采集毛乌素沙地荒漠化草原区春、夏、秋、冬四季的主要牧草品种,并进行常规营养成分分析。夏季牧草品种最全、产草量高、放牧时间长,且牧草营养价值高,因此,对夏季的牧草品种应用康奈尔净碳水化合物—蛋白质体系（CNCPS）对碳水化合物和蛋白质成分进行分类分析,并比较了CNCPS分析方法测得可降解蛋白含量（SCP）和饲料概略养分分析方法测得蛋白含量（CP）间是否存在不一致性。结果表明,毛乌素沙地荒漠化草原区常见牧草品种干物质率从春季到冬季均显著提高（P〈0.05）;四季的蛋白质含量差异较大,且除委陵菜外,从春季到冬季均逐季下降;中性洗涤纤维（NDF）和酸性洗涤纤维（ADF）大部分呈上升趋势,且差异较大。夏季芨芨草、羊草、委陵菜、寸草苔及旋复花间测得的SCP和CP均呈现不一致性。说明CNCPS能够更准确和细致地反映饲草料的特性,为草场的科学利用提供了基础理论数据。     

若干禾本科牧草在荒漠草原区的适应性及其生产性能和营养价值评价

于2000-2004年,采用小区试验法研究了来源于中国、美国和加拿大的23个禾本科牧草材料在内蒙古高原锡林郭勒盟苏尼特右旗小针茅荒漠草原的适应性、产草量和营养价值。结果表明:内蒙沙芦草、沙生冰草、沙芦草、蒙古冰草新品系、新麦草P2、新麦草P3和错行新麦草的越冬率大于80%,生产性能好,根量大,水平根幅大,垂直入土深,粗蛋白含量高,可作为荒漠草原地区推广种植的优质牧草。     

Testing for Thresholds in a Semiarid Grassland: The Influence of Prairie Dogs and Plague

State-and-transition models for semiarid grasslands in the North American Great Plains suggest that the presence of herbivorous black-tailed prairie dogs (Cynomys ludovicianus) on a site 1) creates a vegetation state characterized by increased dominance of annual forbs and unpalatable bunchgrasses and increased bare soil exposure and 2) requires long-term (> 40 yr) prairie dog removal to transition back to a vegetation state dominated by palatable perennial grasses. Here, we examine 1) how the recent history of prairie dog occupancy on a site (1–10 yr) influences the magnitude of prairie dog effects on vegetation composition and 2) how occupancy history affects vegetation dynamics following extirpation of prairie dogs. We used a natural experiment in the shortgrass steppe of northeastern Colorado, USA, where prairie dogs were extirpated from multiple sites during an outbreak of epizootic plague. On sites occupied by prairie dogs for 1–4 yr prior to extirpation, plant cover and composition recovered to conditions similar to unoccupied sites within a single growing season. Larger reductions in perennial C₄ grasses occurred on sites occupied for the prior 7–10 yr compared to sites with shorter occupancy histories (< 6 yr). On sites occupied for the prior 7–10 yr, C₄ perennial grasses recovered after 5 yr following prairie dog extirpation; in addition, C₃ perennial graminoids and forbs remained more abundant (compared to sites with no history of prairie dogs) throughout the 5-yr period. Our findings showcase that prior site occupancy (up to 10 yr) by prairie dogs did not induce irreversible shifts in vegetation state in this semiarid grassland. Rather, vegetation changes induced by prairie dogs represent primarily a phase shift in landscapes where prairie dog populations are regulated by epizootic plague.     

河西走廊北部荒漠草地长爪沙鼠防治指标研究

长爪沙鼠是河西走廊北部荒漠草地的优势鼠类,危害严重。古浪县位于河西走廊东部,北部荒漠草地的长爪沙鼠,5月鼠密度在29．1只／hm^2～52．3只／hm^2之间,至9月造成牧草损失586kg／hm^2。通过调查鼠密度和牧草损失量,结果充分显示长爪沙鼠的种群密度与其造成的损失量之间呈明显的正相关关系,其回归方程式为：M=13．96×-8．10。通过防治及综合分析研究后提出在河西走廊的古浪县北部荒漠草地长爪沙鼠的防治指标为5．33只／hm^2,5月份防治。     

甘肃省主要优良牧草种质资源野外调查

对甘肃省境内主要类型草场的主要野生牧草种质资源分布和现状进行了调查。调查范围涉及河西走廊、祁连山区、甘南高原、黄土高原和陇南西秦岭山区等不同地貌类型的温带阔叶林、温带针叶林、温带典型草原、温带草甸草原、高寒草甸、高寒灌丛、盐化草甸、沼泽化草甸、温带灌丛、温带荒漠等植被型。对不同植被的38个样点植物群落的主要成分进行了记载分析,了解了以豆科、禾本科为主的各植物种的分布现状。在调查的过程中共涉及植物157种,分属14科50属,其中草甸种有90余种,草原种有50余种,荒漠种有10余种;禾本科植物59种,豆科植物19种。调查采集了以豆科和禾本科为主的55个可作为牧草利用的植物种的96份种质材料,并采集了106份植物标本。作为种质材料,保存了可作为牧草利用的植物种子146份1 050 g。     

蜥蜴对内蒙古典型草原群落多样性和地上生物量的影响

为研究蜥蜴(Phrynocephalus frontalis)活动对内蒙古典型草原群落多样性、地上生物量、群落结构、生活型组成以及优势种生物量的影响,于2012年6月和8月在内蒙古毛登牧场围封草场内布设有蜥蜴样地和对照样地,进行样方调查和生物量取样.结果表明:与对照样地相比,蜥蜴样地6月的Shannon-Wiener指数和均匀度显著降低,8月Shannon-Wiener指数、均匀度和物种丰富度均显著低于对照样地;蜥蜴样地的群落生物量在6月和8月分别比对照样地高68.85和111 g·m^-2;在功能群水平,蜥蜴样地一年生植物和多年生禾草的生物量比例比对照样地增加了19.1%和11.0%,而多年生杂类草生物量比例降低了19.8%;在物种水平,蜥蜴样地羊草(Leymus chinensis)生物量的比例在生长季节初期达到了75.0%.可见在内蒙古典型草原,蜥蜴干扰可使一年生植物和多年生禾草的生物量比例增加,而使多年生杂类草的物种数和生物量比例显著降低;蜥蜴干扰显著促进了羊草的生长;同时会降低群落的物种多样性,提高地上生物量.     

Legumes in Chinese Natural Grasslands: Species,Biomass, and Distribution

The composition and abundance of legumes affect the economic value and ecological sustainability of natural grasslands. We collected data on species richness and aboveground biomass of legumes and their percentages of the total community at 78 field sites in Chinese natural grasslands on the Tibetan Plateau (alpine steppe and alpine meadow) and in Inner Mongolia (meadow steppe, typical steppe, and desert steppe), and analyzed the association between these attributes with community, climate, and soil factors. At least one legume species occurred in 89.7% of the sites studied; the genera Astragalus, Oxytropis, and Medicago were dominant among the 12 legume genera recorded. Generally, within 1 m² of grassland, only one legume species was present with an aboveground biomass of 1.1 g; this accounted for 9.1% of community species richness and 1.7% of total aboveground biomass. In comparison with many other types of grassland around the world, both the legume aboveground biomass and its percentage of the total were low in Chinese grasslands, especially in Inner Mongolia. The low biomass of legumes in grassland might be attributable to the low growing-season temperature on the Tibetan Plateau, while in Inner Mongolia, low precipitation combined with high temperatures during the growing season may be the main reason. Although legumes in Chinese grasslands have substantial potential for nitrogen fixation and contain a variety of forage species, their ecological and economic value has been limited by their low biomass. Suggestions to enhance legume biomass in Chinese grasslands are provided.     

耐盐牧草对南疆地区盐渍土的适应和改良研究

以4种耐盐碱牧草(紫花苜蓿、苏丹草、美国饲用甜高粱和墨西哥玉米)为研究对象,采用生物防治盐碱化方法来分析其对南疆地区盐碱化土壤改良的可行性,以期为改良利用盐渍土壤提供理论基础。结果表明,墨西哥玉米对南疆盐渍土的改良最为显著(P<0.05),其农艺性状和产草量也最佳;其次是紫花苜蓿,其抗逆性强、生产性能较好、营养丰富、经济价值高以及兼有固氮和提高土壤肥力等优点,使其成为改良南疆盐渍土合适的选择。在南疆盐渍区形成以墨西哥玉米和紫花苜蓿为主,美国饲用甜高粱和苏丹草为辅的种植模式,可有效地降低土壤盐分。     

Prescribed Fire,Grazing, and Herbaceous Plant Production in Shortgrass Steppe

We examined the independent and combined effects of prescribed fire and livestock grazing on herbaceous plant production in shortgrass steppe of northeastern Colorado in the North American Great Plains. Burning was implemented in March, before the onset of the growing season. During the first postburn growing season, burning had no influence on soil moisture, nor did it affect soil nitrogen (N) availability in spring (April–May), but it significantly enhanced soil N availability in summer (June–July). Burning had no influence on herbaceous plant production in the first postburn growing season but enhanced in vitro dry matter digestibility of blue grama (Bouteloua gracilis [Willd. ex Kunth] Lag. ex Griffiths) forage sampled in late May. For the second postburn growing season, we found no difference in herbaceous plant production between sites that were burned and grazed in the previous year versus sites that were burned and protected from grazing in the previous year. Our results provide further evidence that prescribed burns conducted in late winter in dormant vegetation can have neutral or positive consequences for livestock production because of a neutral effect on forage quantity and a short-term enhancement of forage quality. In addition, our results indicate that with conservative stocking rates, deferment of grazing during the first postburn growing season may not be necessary to sustain plant productivity.