The effect of four different pasture species compositions on nitrate leaching losses under high N loading     

B. J. Malcolm  K. C. Cameron  H. J. Di  G. R. Edwards  J. L. Moir 《Soil Use and Management》2014,30(1):58-68

Nitrate () leaching can cause elevated concentrations of ‐N in water, which can have adverse impacts on water quality and human health. In grazed pasture systems, most of the ‐N leaching occurs beneath animal urine‐N deposits. The objective of this study was to investigate the effect of four different pasture species compositions [perennial ryegrass/white clover (P. ryegrass WC), tall fescue/white clover (T. fescue WC), Italian ryegrass/white clover (It. ryegrass WC) and perennial ryegrass/Italian ryegrass/white clover/red clover/chicory/plantain (Diverse)] on ‐N leaching losses from animal urine patches, and to examine the relative importance of root system architecture and seasonal activity to reduce ‐N leaching losses. The results show that ‐N leaching losses were 24–54% lower beneath It. ryegrass WC than other pasture species. Total dry matter (DM) yield in the season following establishment was 11–58% greater in the It. ryegrass WC pasture, while average winter daily N uptake rate of It. ryegrass WC over the two seasons was on average 58% greater than P. ryegrass WC and T. fescue WC. In the second season, the P. ryegrass WC and T. fescue WC pastures had up to 140 and 82% more roots between 0 and 40 cm depth, respectively, than the other pasture species compositions. These results suggest that in grazed pasture systems, high plant winter activity (plant growth/root metabolic activity) is more important than specific root architecture (e.g. deep roots) to reduce ‐N leaching losses.  相似文献   

放牧强度对南方人工草地和绵羊生产性能的影响(简报)   总被引：1，自引：0，他引：1  

朱兴宏  张英俊  朱晓艳  刘荣堂  夏显著  秦浩  戴兴朝  付丽 《草地学报》2009,17(1):128-130

放牧强度对草地生存环境和家畜生产性能关系密切^[1]。我国对放牧强度的研究集中于北方^[2],南方草地建设比较晚,尤其是南方人工草地相关研究比较少。本试验旨在探讨南方人工草地不同放牧强度与草地植物产量和放牧家畜生产性能之间的关系,为确定合理的载牧量提供参考依据。  相似文献   

水热条件与特定区域天然牧草生物量的关系   总被引：8，自引：1，他引：7  

金磊  张伟  菅晓蕾 《内蒙古农业科技》2008,(3):71-72

天然牧草生物量与气候因素存在着不可分割的联系,但气象因素对植物生长发育或生物量的影响并非是简单地与某个气象因子有关,植物在生长发育的不同阶段,同一气象要素所反映的作用效果具有很大的差异。文章在前人工作的基础上．对天然牧草生长发育各个阶段的气象因子进行分析,讨论了天然牧草生物量的时空分布与水热条件的关系。  相似文献   

Pasture and forage crop systems for non-irrigated dairy farms in southern Australia. 1. Physical production and economic performance     

D.F. Chapman  S.N. Kenny  D. Beca  I.R. Johnson 《Agricultural Systems》2008

The dairy industry in southern Australia relies on perennial ryegrass pasture to supply 60–70% of the diet of lactating cows. Improvements in the amount and quality of home-grown forage used for dairy cow feeding are critical for further productivity gains in the industry. A modeling approach was used to estimate the effects of changing the forage system on farm business profit. Base models (using 100% of farm area in perennial ryegrass pasture) were constructed for above-average (Top 40%) and high performing (Top 10%) farm types typical of two locations: Terang in southwest Victoria and Ellinbank in Gippsland, eastern Victoria. These models were then re-simulated using different forage base options such as: oversowing annual ryegrass, winter crops (annual ryegrass monoculture, winter cereal grown for whole crop silage), summer crops (grazing brassicas, maize), combinations of these (double cropping), or summer shoulder pasture (notionally based on tall fescue) on between 10% and 100% of farm area.  相似文献   

高丹草新品种在河北平原农区的引进筛选   总被引：3，自引：1，他引：2  

刘贵波  乔仁甫 《中国农学通报》2005,21(6):383-383

在河北平原农区,通过对国内外11个高丹草新品种的产草量、粗蛋白产量、物候期、分蘖力、再生性、株高等性状的研究分析,结果表明：以青饲、青贮饲喂牛为目的,表现最好的品种为健宝,不仅产草量高、粗蛋白产量、分蘖能力、再生性、长势均较好。其次为晋草1号、瑞奥3号。高丹草在河北平原农区春播、夏播均可,春播可刈割三次,夏播可刈割二次。  相似文献   

苜蓿对盐碱的适应性   总被引：5，自引：3，他引：2  

柴琦  张建全  陈宝书  刘国荣  王永宁 《草地学报》2007,15(3):293-295

我国约有盐渍化土地1亿公顷,其中盐土地和盐土荒地2667×10⁴hm^2[1],约占全国耕地的21%^[2]。甘肃省河西走廊地区次生盐渍化十分严重,致使大面积农田变为盐碱地,成为低产田或弃耕地,使得土地的利用率受到限制。  相似文献   

河南省黄河滩区绿色草业工程建设的现状与展望   总被引：3，自引：0，他引：3  

李明  郭孝 《中国农学通报》2006,22(11):44-44

笔者根据河南省黄河滩区自然条件的特点和畜牧业发展中存在的问题,依据生态学原理探讨了在滩区建设绿色草业工程的必要性和可行性。文章的重点在于提出建立以发展“三元”农业生产结构、发展绿色草业工程、发展绿色畜禽产品小区以及加强生物多样性保护为核心的绿色综合建设措施,其目的是为了改善黄河滩地的生态环境,保护滩地的生物多样性,促进滩区湿地以及周边地区农田和草地的科学化利用,促进滩区农牧业经济的良性循环和可持续发展。  相似文献   

牧草遗传连锁图谱构建研究概述   总被引：1，自引：0，他引：1  

方程  韩建国 《草地学报》2006,14(3):287-291

高密度分子连锁遗传图谱对分析植物遗传变异、标记目标性状、数量性状定位和分子辅助选择改良性状均具重要价值。由于大多数牧草的多倍性和高度异质特点,牧草遗传连锁图谱的构建相对复杂。目前,一定数量牧草的遗传连锁图谱已经产生。本文简要综述了牧草遗传图谱研究现状和常用策略,提出了构建高质量牧草遗传图谱的建议。  相似文献   

雀稗草产草量、营养价值及饲喂效果的研究   总被引：4，自引：1，他引：3  

谢国强  何余勇  程树芳  刘经荣  石庆华  谢永中  季梦成 《草地学报》2004,12(1):31-35

连续二年测定雀稗草鲜草、干草、干物质、粗蛋白质和可消化干物质产量,分析各生长阶段常规营养成分;进行饲养肉牛效果试验,同时测定干物质消化率。结果表明,雀稗草具有产草量较高、幼嫩时期营养成分含量丰富、干物质消化率高等优点,但后期老化快,抽穗开花后营养价值急剧下降;相关分析结果表明,粗纤维含量与生长天数呈显著正相关(P<0.05),而粗蛋白质含量则呈显著负相关(P<0.05);刈割高度60cm优于50cm;用雀稗草饲喂肉牛有必要补充一定量的精料(5g/kgLW/d)或较多量的豆科牧草。  相似文献   

草鱼口服出血病疫苗的免疫途径及效果   总被引：4，自引：1，他引：3  

陈宇  戚少燕  程起群  王永杰  卢文轩  江河  李燕和  管远亮 《安徽农业科学》2000,28(2):247-248,251

用草鱼出血病病毒疫苗处理鱼苗开口饵料 ,以口服法接种草鱼苗 ,分别于第 76、119d后测定了不同浓度下免疫草鱼的血清抗体滴度。采用方法简单、成本低廉的琼脂扩散法 ,即可测出有效免疫浓度下的血清抗体滴度为 1:8～ 1:16,相应浓度下的免疫保护力为 80 %～ 10 0 %  相似文献