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华北农牧交错带人工草地放牧系统植物补偿性生长研究 总被引：3，自引：3，他引：3
研究华北农牧交错带不同人工草地在不同放牧强度下的总净生长量及净生长量的变化.结果表明,无芒雀麦-杂花苜蓿草地在任何放牧强度下均表现为超补偿性生长,即净生长量增加;新麦草-杂花苜蓿和杂花苜蓿-新麦草-扁穗冰草草地在轻度放牧下,总净生长量增加,在中度和重度放牧条件下分别表现为等补偿性生长和欠补偿性生长;新麦草草地在轻牧下呈超补偿性生长,在中牧下为等补偿性生长,重牧时表现欠补偿性生长;杂花苜蓿净初级生产力变化同新麦草草地一致;无芒雀麦在所设放牧强度下均表现为超补偿性生长,表明其耐牧性极强.因此,草地放牧强度应根据其组成种群来确定,以保证可持续利用. 相似文献
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奶牛放牧对北方农牧交错带人工草地植被的影响 总被引：2，自引：2，他引：0
研究了不同处理奶牛放牧对混播人工草地植被的影响。结果表明,牧草现存量随着放牧强度的增加而降低,轻牧比中牧高7.28%,且轮牧高于连续放牧1.99%,轮牧对紫花苜蓿和无芒雀麦的再生有利。随放牧强度增加,紫花苜蓿和无芒雀麦重要值下降,蓝茎冰草和新麦草增加。放牧对牧草的茎叶比有显著影响,放牧后4种牧草的茎叶比均有下降,连续放牧高于轮牧。根系主要集中在土壤表层0~10 cm,约占0~30 cm总量的70%,且其生物量也以轮牧制较高,随放牧强度的增加而下降。 相似文献
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5种多年生禾草在高寒地区旱作栽培条件下的品种比较试验表明,粉绿披碱草、多叶老芒麦、短芒老芒麦、无芒雀麦、扁穗冰草在高寒地区旱作条件下生长正常,表现良好,其中以披碱草属的3种牧草和冰草属的扁穗冰草相对稳产,表现最好,无论从产量还是经济性能等方面均表现最佳,而无芒雀麦在高寒地区稳产性最差。 相似文献
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5种禾草在高寒地区旱作条件下的牧草产量分析 总被引：1，自引：0，他引：1
5种多年生禾草在高寒地区旱作栽培条件下的品种比较试验表明，粉绿披碱草、多叶老芒麦、短芒老芒麦、无芒雀麦、扁穗冰草在高寒地区旱作条件下生长正常，表现良好，其中以披碱草属的3种牧草和冰草属的扁穗冰草相对稳产，表现最好，无论从产量还是经济性能等方面均表现最佳，而无芒雀麦在高寒地区稳产性最差。 相似文献
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黑龙江省西部半干旱区牧草引种筛选研究初报 总被引：5，自引：0，他引：5
对不同来源的20种牧草进行了两年的引种筛选试验研究，结果表明：豆科的肇东苜蓿、公农1号苜蓿、草原2号苜蓿和禾本科的无芒雀麦、林肯无芒雀麦、扁穗冰草、细茎冰草，在2001年极其干旱年份越冬率、产草量、抗逆性、分枝（分蘖）数、茎叶比都优于其它13个品种；而苜蓿品种国内的优于国外品种。由此认为，这7个牧草品种是黑龙江省寒冷干旱区、半干旱区建立人工草地、改良退化沙化草地的优良草种，可大力推广种植。 相似文献
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放牧强度和草地类型对育肥羔羊生产性能的影响 总被引：7，自引：1，他引：6
在华北农牧交错带坝上地区 ,研究放牧强度和草地类型对肥育羔羊生产性能的影响。结果表明 ,在育肥期间 ,放牧强度对育肥羔羊个体增重的影响主要与季节有关。试验结束时 ,供试羔羊体重间差异不显著 (P>0 .0 5) ,但是单位面积家畜生产性能之间差异极显著 (P<0 .0 1 ) ,其中以重牧区畜产品产量最高 ,达 1 92 .53kg/hm2× 1 0 8d,中牧和轻牧区分别为 1 81 .6和 1 1 0 .9kg/hm2 × 1 0 8d。杂花苜蓿—扁穗冰草—新麦草草地对羔羊育肥增重效果最为显著 (P<0 .0 5)。放牧强度和草地类型互作对羔羊的增重差异极显著 (P<0 .0 1 )。不同草地类型适宜的放牧强度各异。羔羊干物质和蛋白质日采食量均随着放牧强度的增加而降低 相似文献
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14个多年生牧草品种在川西北高寒牧区适应性研究 总被引：2，自引：0，他引：2
采用田间小区方法,以2014~2017年在四川省甘孜州道孚县乾宁种畜场对早熟禾(Poa pratensis)、多年生黑麦草(Lolium perenne)、雀麦(Bromus inermis)、猫尾草(Phleum pratense)、细茎冰草(Agropyron trachycaulum)、扁穗冰草(Agropyron cristatum)和紫花苜蓿(Medicago sativa)共14个品种同期播种,连续4年进行田间观察和产草量测定。结果表明:在川西北地区种植的14个牧草品种细茎冰草因越冬率低,不适应当地环境,在2016年低全部死亡,其余13个草品种都可安全越冬,正常生长,但不同品种产草量差异显著或极显著。从产量总趋势分析,诺言猫尾草、乌苏1号无芒雀麦、热销多年生黑麦草、新速Ⅱ多年生黑麦草、三得利紫花苜蓿等5个品种产量较高,值得在本区生产上应用推广。 相似文献
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《Strength and Conditioning Journal》2007,60(1):71-78
Studies of Anderson and Scherzinger's forage conditioning hypothesis have generated varied results. Our objectives were: 1) to evaluate late summer/early fall forage quality of crested wheatgrass (Agropyron desertorum [Fisch. ex Link] J. A. Schultes), bluebunch wheatgrass (Pseudoroegneria spicata [Pursh] A. Löve), Idaho fescue (Festuca idahoensis Elmer), bottlebrush squirreltail (Elymus elymoides [Raf.] Swezey), Thurber's needlegrass (Achnatherum thurberianum [Piper] Barkworth), and basin wildrye (Leymus cinereus [Scribn. & Merr.] A. Löve) from ungrazed paddocks and paddocks grazed at vegetative, boot, and anthesis; and 2) test hypotheses that postgrazing regrowth yields were correlated with soil moisture content when grazing occurred. Crop–year precipitation for 1997 and 1998 was 134% and 205% of average. Crude protein (CP) and in vitro dry matter digestibility (IVDMD) of ungrazed grasses displayed expected declines in quality. Among ungrazed grasses, late summer/early fall CP was 5.7% in 1997 and 3.6% in 1998; IVDMD was 47% and 41%, respectively. Late summer/early fall forage quality was elevated by vegetative, boot stage, or anthesis grazing. The phenologically youngest regrowth always ranked highest in CP and IVDMD. Among grasses, respective 1997 CP and IVDMD means were 9.0% and 55% for regrowth following anthesis grazing. No regrowth followed anthesis grazing in 1998, but CP and IVDMD means from boot stage treatments were 5.5% and 47%, respectively. With CP measures, a species by treatment interaction occurred in 1997, but species reacted similarly in 1998. Vegetative, boot stage, and anthesis grazing in 1997 caused respective late summer/early fall standing crop reductions of 34%, 42%, and 58%; and 34%, 54%, and 100% reductions in 1998. Forage conditioning responses were lower for bluebunch wheatgrass and crested wheatgrass than other grasses. Soil moisture content was a poor predictor of regrowth yields. Managed cattle grazing can successfully enhance late season forage quality. 相似文献
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《Strength and Conditioning Journal》2005,58(2):177-183
Crested wheatgrass (Agropyron cristatum [L.] Gaertn.) and Russian wildrye (Elymus junceus Fisch.) are commonly used for reseeding in the more xeric Mixed Prairie of the Canadian prairies because they are perceived to be more productive than native species. However, they have been implicated in soil deterioration. The objectives of our study were to compare the aboveground net primary production and soil organic carbon (C) among monoculture communities of selected native grass species, crested wheatgrass, and Russian wildrye and to compare the native grass monocultures with their mixtures. In 1995, a 5-year study was initiated on Dark Brown Chernozemic (Typic Haploboroll) soil near Lethbridge, Alberta. Ten treatments consisting of monocultures of introduced and selected native species and mixtures of native species were established in a randomized complete block design with 4 replications. Aboveground net primary production and soil organic C were measured. Monocultures of 2 native species, green needlegrass (Stipa viridula Trin.) and blue grama (Bouteloua gracilis [H.B.K.] Lag. ex Steud.), were more productive than crested wheatgrass or Russian wildrye under both normal moisture and drought conditions. Monocultures of these native species also tended to be more productive than their mixtures. The western wheatgrass (A. smithii Rydb.) monoculture and the western wheatgrass–blue grama mixture experienced the greatest yield reduction as a result of drought. Treatment effects on soil organic C were not detected (P > 0.05) 5 years after seeding. Soils of the June grass (Koeleria macrantha [Ledeb.] J.A. Schultes f.) community had less (P < 0.05) macro-organic C than most other treatments. 相似文献
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混播比例和刈割期对混播草地产量及品质影响的研究 总被引：6，自引：2，他引：4
在新疆石河子进行了不同混播比例和不同刈割期对紫花苜蓿Medicago sativa和无芒雀麦Bromus innermis混播草地产量及品质影响的研究。结果表明：以紫花苜蓿50%（7.5 kg/hm2）+无芒雀麦50%（15 kg/hm2）混播比例的混播草地产草量最高,达到21.3 t/hm2,刈割期处理T2（紫花苜蓿初花期）产草量最高。刈割期对紫花苜蓿品质存在着明显的影响。处理T1（紫花苜蓿现蕾期）的粗蛋白含量最高,中性洗涤纤维和酸性洗涤纤维含量最低（P<0.05）;刈割期对混播草地无芒雀麦和紫花苜蓿品质存在一定的影响,其中混播处理A1（紫花苜蓿与无芒雀麦5∶5）紫花苜蓿和无芒雀麦的品质较好。 相似文献