留茬高度对人工草地牧草产量及质量的影响

试验对黑麦草／白三叶混播草地在不同留茬高度下的生产特性进行了分析研究,研究结果表明,草地牧草的枯死率与留茬高度呈正比关系,在不同留茬高度下,草地牧草青绿物质的生长速度和产量呈抛物线形式变化;青绿牧草产量占牧草总产量的百分比随留茬高度的上升而下降,而死亡物质的数量占牧草产量的百分比随留茬高度的上升而增加。     

人工草地绵羊系统优化研究Ⅵ夏秋季剩余牧草收贮与人工草地畜牧业可持续发展

夏秋人工草地剩余牧草收贮是云贵高原人工草地合理利用的关键措施之一,青贮是牧草收贮的切实可行的方案.牧草收贮可调节牧草供应季节平衡;促进牧草再生,提高草地产量,改善利用均匀度,控制杂草,防止草地退化;提高牧草利用率,减少牧草枯腐;提高牧草质量和消化率;减少冬春青绿饲料生产及精饲料供给量,降低生产成本;最终提高草地畜牧业的经济效益并实现可持续发展.     

青海省海南州天然草地及牧草多样性分析

通过对海南州天然草地牧草多样性分析,进一步了解其天然草地的生态环境,为合理利用、改良和保护草地提供参考依据。据分析,温性草原类牧草多样性指数在３．２￣４．６之间,多样化程度较低;高寒草原类、高寒草甸类牧草多样性指数在３．３￣６．６之间,多样化程度高于温性草原类。从总体而言,海南州草地牧草多样化程度较低,主要是水、热两大因子分配不均所致。有些草地型虽然牧草种类较多,但由于分布不均匀,导致了牧草多样化     

青海天然草地牧草能值分析

利用测定资料及西德奥斯卡凯尔纳的预测能值公式,对青海天然草地3个主要草地类15个草地型的牧草能值,消化能,代谢能进行了预测分析。结果表明:以高山嵩草为优势种的草地牧草其TDN、DE、ME均较高,山地干草原类,高寒干草原类各草地型牧草DE、ME均较低。     

高寒草甸草地牧草产量及其营养

高寒草甸草地是青海省草地畜牧业生产的主要物质基础。对所测高寒草甸草地实行全年封育，于7月、8月、9月测定草地地上生物量和营养物质。测定结果表明：①牧草产量以8月分最高，小嵩草甸干草产量可达43．7g/m^2，灌丛草甸可达109．9g/m^2；②与环湖地区相同类群牧草相比，牧草粗蛋白含量高，粗脂肪含量高，粗纤维含量低。牧草粗蛋白质含量随生长期的延长而降低，牧草粗纤维含量变化与之相反。牧草中锌含量缺额，硒、铜含量严重缺乏，必须对该区牲畜补饲硒、铜、锌制剂。     

牧草品种资源在云南草地畜牧业发展中的作用

本文介绍了云南野生牧草资源，天然草地资源，国外引进的主要优良牧草品种资源以及人工草地建植概况，阐述牧草品种资源在云南草地畜牧业发展中的作用，旨在阐明牧草品种资源引种研究的重要性。     

高寒地区退化草地改良试验研究

为改善草地植物生存条件,对退化草地进行了改良试验研究,结果表明,３种改良方法都能改善草地生境,增中土壤速效养分。以施肥效果最佳,增加了牧草在草群中比重。禾本科、豆科和莎草科牧草分别比对照区增加９．０２－１０．１７％、１８．４０－２７．７６％和－６．７５％－１．８７％; 柯食牧草增加１倍;围栏封育草地效果次之,禾本科和豆科牧草在草群中所占比重分别比对照区增加２６．８１－３９．８５％和２０．７４－３７     

天然草地牧草青贮技术研究进展

天然草地牧草青贮技术可以长期、安全、高效贮藏优质牧草,有效防除针茅对家畜的伤害,是维护草原生态健康和草地畜牧业稳定发展的适用技术。本文对国内外天然草地牧草青贮技术的研究内容、应用及效果等方面的发展历史与研究现状进行了概述,提出了当前天然草地牧草青贮技术中的主要问题及今后的发展方向,以期为调制优质天然草地牧草青贮饲料及安全利用提供可借鉴的依据与实践参考。     

巴基斯坦的草地现状和草地开发

通过对巴基斯坦的高山草地，亚高昌地，温带草地，山前丘陵草地和干旱草地５种类型草地的利用现状调查的分析。认为引起草地严重退化的主要原因是草地载畜量过大和不合理的利用。通过设立专门的草地管理机构，制定科学的草地管理政策，加强草地管理，采取诸如不同类型草地引入适合的优良牧草品种等，改良草地，增加良种畜的饲养量，以及大幅度减少生产性能差的畜群，对草地进行科学合理的利用，加强对牧民的培训及其它相应的措施，使     

高山草甸草地牧草产量及其营养变化规律

高山草甸草地是青海省主要冬春放牧地，占冬春草地总面积的４７．９６％。对所测高山草甸草地实行全年封育，每月测定草地地上生物量和营养物质。测定结果表明：①牧草产量以８月份最高，９６．８２ｇ／ｍ＾２，翌年５月最低，２２．２５ｇ／ｍ＾２，全年呈单峰型，牧草营养物质总产量亦是如此规律，牧草粗蛋白质含量和粗纤维含量随牧草生长期的推移呈负相关（ｒ＝－０．８９５）；②冬春季节牧草经长时间的日晒、风吹，自然损失严重     

放牧生态系统中的组织物质循环及其在牧场管理中的应用

综述了组织物质循环的理论及其在牧场管理中的应用。放牧过程中牧地草丛内的物流和能流循环是维持放牧生态系统平衡的重要基础,进行牧地草丛中植物组织循环,特别是其生长和萎蔫死亡的动态分析,为草地的有效利用提供了理论依据。文中对于牧地草丛内及刈牧过程中的组织物质循环,连续放牧及间断放牧条件下的组织物质循环进行了重点分析论述。建议在中国各类型草地上应用组织物质循环理论开展放牧管理研究,以推动草地管理理论和实践的发展。     

刈割对羊茅黑麦草和无芒雀麦蘖转化的影响

根据种群生命统计分析原理，进行了刈割对羊茅轩麦草和无芒雀麦蘖转化的影响的研究。结果表明，羊茅黑草经元芒雀麦有较低的蘖死亡率和较高的蘖出现率，在营养期对刈 茅黑麦草优于繁殖期，应避免频繁强度利用元芒雀麦，羊茅黑草则适合频敏地强度与轻度结合刈牧。     

不同生长阶段群体数量特征对产草量作用的分析

在相同的光，温，水，肥条件下，同时对营养生长期的高羊茅和生殖生长期的多年生黑麦草人工草地产草量和群体数量特征的定量关系进行研究。在营养生长期，参数的变异程度小于生殖生长期。营养生长期各因子对产草量直接作用的程度排序这：叶面积指数〉草丛高度〉分蘖密度，生殖生长期为；草丛高度〉叶面积指数〉分蘖密度。     

Plant and sward response to patch grazing in the Highland Sourveld

Abstract

Selective grazing by livestock inevitably results in patch grazing. This study was initiated to determine the effects of patch grazing on (1) the vigour of a single grass species, Themeda triandra, and of the sward, and (2) sward species composition. The generally held idea that a full season's rest followed by an early spring burn would prevent preferential grazing of patch grazed areas which had developed in the seasons before the rest was also tested. The vigour of 71 triandra was estimated from etiolated growth of marked tufts while sward vigour was indexed by above‐ground herbage production (AGHP). Etiolated growth of T. triandra and AGHP of the sward within patches were negatively affected by three seasons of grazing, but a full season's rest appeared sufficient to restore both the etiolated growth of T. triandra and the AGHP of the sward to a level similar to that in the non‐patches. A full season's rest followed by spring burning did not, however, prevent preferential grazing of grazed patches which had developed in the seasons prior to the rest. Species composition within patches (characterised by Increaser II species) differed significantly from the species composition of non‐patches (characterised by Increaser I species). Patch grazing may therefore initiate the rangeland degradation process in Highland Sourveld and patch grazing may be the focus from which rangeland degradation proceeds.     

Direct measurement of dispersal of Dictyocaulus viviparus in sporangia of Pilobolus species

Dispersal of Dictyocaulus viviparus larvae by Pilobolus sporangia was studied on 29 faecal pats deposited between the end of June and late October 1988. Faecal pats were covered daily from day 3 to 4 after deposition with a large petri dish to measure the numbers of sporangia released and the numbers of larvae carried. The yield of both was variable. Dispersal of lungworm larvae was lowest on over-grazed pasture or when Pilobolus growth was very poor. When faecal pats were sheltered by a long sward, 17 per cent or more of larvae present at deposition were transported in this manner. In July and August, peak dispersal of lungworm larvae was on day 5, in September on day 6 and in October on day 7, the increasing time intervals being probably associated with decreasing temperature.     

短花针茅草原放牧系统植物补偿性生长的研究：Ⅰ.植物净生长量

试验于１９９６￣１９９７年在内蒙古农牧学院哈雅教学牧场，研究２岁杂种羯羊在短花针茅荒漠草原不同载畜率下植物的净重复一。结果表明，１９９６年５个载畜率处理地上净生长量与对照区差异不显著（Ｐ〉０．０５），植物表现等补偿性生长。在１９９７年干旱年份，当载畜率小于２．０只羊／半年／ｈｍ＾２时，放牧区地上净生长量与对照间差异不显著（Ｐ〉０．０５），植物表现等补偿性生长。当载畜率大于２．０只羊／半年／ｈｍ＾２     

Stocking Rate and Riparian Vegetation Effects on Physical Characteristics of Riparian Zones of Midwestern Pastures

Grazing at high stocking rates may increase sediment and nutrient loading of pasture streams through transport in precipitation runoff and bank erosion. A 3-yr (2007–2009) grazing study was conducted on 13 cool-season grass pastures to quantify effects of stocking rate and botanical composition on forage sward height, proportions of bare and manure-covered ground, and bank erosion adjacent to streams. Pastures ranged from 2 ha to 107 ha with stream reaches of 306 m to 1 778 m that drained watersheds of 253 ha to 5 660 ha. Bare and manure-covered ground were measured at a 15.2-m distance perpendicular to the stream at 30.5-m intervals at up to 30 locations on each side of the stream by the line transect method in May, July, September, and November of each year. At the midpoint of the 15.2-m line, forage sward height was measured with a falling plate meter (4.8 kg · m^-2) and plant species identified. In November 2006, fiberglass pins (1.6 × 76.2 cm) were driven 73.7 cm into the stream bank at 1-m intervals from the streambed to the top of the bank along 10 equidistant transect locations on each side of the stream to measure bank erosion during spring, summer, and fall of each year. Increasing pasture stocking rates increased manure-covered ground and decreased sward height, but did not affect proportions of bare ground. The greatest, intermediate, and least net soil erosion rates occurred during the winter/early spring, late spring/early summer, and late summer/fall seasons. Stocking rates between measurements, expressed as cow-days · m^-1 stream, were not related to bank erosion. Increasing stocking rates per unit of stream length will increase manure cover and decrease forage sward height, but not affect proportions of bare ground or bank erosion rates adjacent to pasture streams. Therefore, managing stocking rates may reduce nutrient loading of pasture streams.     

优良冬季青绿禾草扁穗雀麦在人工草地中的建植及利用研究

本试验研究了在贵州中南部的黄棕壤土中建植扁穗雀麦人工草地时 ,不同的播种时期、播种量、播种方法、利用期及不同刈割方式对扁穗雀麦生长发育的影响。其结果表明 :在无灌溉条件下种植扁穗雀麦 ,播期是成败的关键 ,秋旱后播种最好 ;条播稍好于撒播 ,覆土远胜于不覆土 ;播量以 3 0kg/6 6 7m2 为宜 ,其鲜草产量达 6 349 7kg/6 6 7m2 。扁穗雀麦草地生长第一年产量比第二年低 19 4 % ;其越夏率可达到94 7% ,但利用不当则大幅度下降。因此 ,建议在生长第一年留种 ,第二年以始牧高 30cm ,留茬高 6 0cm时开始刈割或放牧利用 ,并在高温伏旱来临之前重施肥料 ,给它一“休养生息”条件 ,既可达高产 ,又有利于越夏     

补播和划破草皮对退化亚高山草甸植被恢复的影响

在甘肃省甘南州临潭县研究围栏内补播和划破草皮对退化亚高山草甸植被的高度、总盖度、地上生物量和功能群物种多样性总指数的影响。结果表明,在各划破草皮处理中,牧草总盖度、地上生物量和功能群物种多样性总指数随着补播量的增加而增加,植被高度随着补播量的增加呈先增加后降低的趋势。补播和划破草皮有显著互作效果,补播量3[垂穗披碱草(Elymus nutans)播量为49.1 kg·hm-2,老芒麦(Elymus sibiricus) 播量为67.5 kg·hm-2,紫花苜蓿甘农1号(Medicago sativa cv.Gannong No.1)播量为23.3 kg·hm-2]和划破草皮组合的牧草地上生物量(201.5 g·m-2)、总盖度(88.2%)和功能群物种多样性总指数(1.203)达到最大值,补播量1（垂穗披碱草播量为26.7 kg·hm-2,老芒麦播量为37.5 kg·hm-2,紫花苜蓿甘农1号为0）和划破草皮组合的植被高度(11.7 cm)达到最大值。就各补播水平平均值而言,划破草皮植被高度、总盖度、地上生物量和功能群物种多样性总指数显著高于未划破草皮。综合考虑高度、总盖度、地上生物量和功能群物种多样性总指数,经关联度分析可知,补播量2（垂穗披碱草播量为37.5 kg·hm-2,老芒麦播量为52.5 kg·hm-2,紫花苜蓿甘农1号18.3 kg·hm-2）和划破草皮为最优组合。