呼和浩特地区旱作混播草地群落特征及其生产力维持机制

发布时间：2018-06-04 11:47

  本文选题：混播草地 + 旱作　； 参考：《内蒙古农业大学》2015年博士论文

【摘要】：内蒙古呼和浩特地区奶牛养殖业的快速发展加大了对高产优质饲草饲料的需求量,饲草供求矛盾突出。本研究于2011年在呼和浩特市和林格尔县公喇嘛镇哈拉沁村建植了苜蓿与禾本科牧草的混播草地及各种牧草的单播草地,通过系统观测旱作条件下草地的生长状况和不同刈割频次、留茬高度和刈割时期的群落,分析了草地随着建植年限的群落特征变化、组分变化和种间关系以及在不同刈割处理下的变化规律,揭示各类草地的生产潜力和适宜的刈割利用方法,探究苜蓿混播草地的群落动态和生产力维持机制,结合综合评价分析方法,提出适宜的苜蓿混播草地组合及其刈割管理制度,为呼和浩特地区的饲草产业发展提供支撑。主要研究结果如下:草地建植初期,老芒麦+苜蓿混播草地产草量明显高于单播老芒麦、单播草地雀麦和单播苜蓿草地(P0.05),草地雀麦+苜蓿混播草地在建植第2年的产量较低,到第4年其产量显著高于老芒麦+苜蓿混播草地和三种单播草地(P0.05)。随着草地建植年限的增加,混播草地和单播苜蓿草地产量逐年显著增长(P0.05),而单播老芒麦和单播草地雀麦的产量显著降低(P0.05)。苜蓿、老芒麦和草地雀麦在混播条件下的产量和植株高度均高于各自的单播(P0.05),但老芒麦和草地雀麦的营养价值低于单播草地(P0.05)。随着草地建植年限的增加,混播群落中苜蓿的产量组分比和重要值明显增加(P0.05),在群落中占据主要地位,而老芒麦和草地雀麦的组分比和重要值逐年降低(P0.05)。低留茬(0~3cm)或高频次(3~4次/年)刈割时草地雀麦+苜蓿混播草地的产量与单播苜蓿之间无差异(P0.05),老芒麦+苜蓿混播草地的产量显著低于单播苜蓿草地(P0.05)。一年2次刈割有利于各草地产量的提高,但随着刈割频次的增加草地产量显著降低(P0.05)。齐地(0cm留茬)刈割显著增加苜蓿的再生速率和年总产量(P0.05),但显著降低老芒麦和草地雀麦的再生能力(P0.05);而7~10cm留茬有利于老芒麦和草地雀麦的再生,降低苜蓿的再生草产量。苜蓿盛花期刈割时两种混播草地和单播苜蓿草地的产量高于单播老芒麦和单播草地雀麦(P0.05),混播草地中苜蓿的产量组分比和重要值随着刈割时期的推迟而明显增加(P0.05),老芒麦和草地雀麦的组分比和重要值明显降低(P0.05)。综合评价结果表明,草地雀麦+苜蓿混播草地的综合生产性能最佳,单播苜蓿草地次之,老芒麦+苜蓿混播草地低于单播苜蓿,但优于单播老芒麦和单播草地雀麦。而且,草地雀麦+苜蓿混播群落的各组分相对稳定于老芒麦+苜蓿混播草地。两种混播草地的适宜的刈割时期均为苜蓿盛花期,刈割频次以2次/年最佳,老芒麦+苜蓿混播草地留茬7cm时产量和稳定性最好,草地雀麦+苜蓿草地留茬5cm为宜。
[Abstract]:The rapid development of dairy cattle breeding in Hohhot area of Inner Mongolia increased the demand for high yield and high quality forage feed and the contradiction between supply and demand of forage grass was prominent. In this study, the mixed grassland of alfalfa and gramineous forage and the unicast grassland of all kinds of forage were established in Haraqin Village, Gongla Town, Helinger County, Hohhot City in 2011. Based on the systematic observation of grassland growth status, cutting frequency, stubble height and cutting period community under dry cropping condition, the community characteristics of grassland with planting years were analyzed. The variation of composition and species, as well as the law of variation under different cutting treatments, revealed the productive potential and suitable cutting methods of all kinds of grassland, and explored the community dynamics and productivity maintenance mechanism of alfalfa mixed grassland. Combined with the comprehensive evaluation and analysis method, the suitable combination of alfalfa mixed sowing grassland and its cutting management system were put forward, which provided the support for the development of forage industry in Hohhot area. The main results were as follows: in the early stage of grassland establishment, the grass yield of alfalfa mixed seeding was significantly higher than that of single seeded Laomangmai, and the yield of single seeded and unicast alfalfa was lower in the second year. In the fourth year, the yield was significantly higher than that of the mixed alfalfa and three monoculture grassland (P0.05N). With the increase of grassland planting years, the yield of mixed grassland and monoculture alfalfa field increased significantly year by year, while the yield of single seeded Laomangwheat and single seeded grass bromegrass decreased significantly (P0.05). Under mixed sowing, the yield and plant height of alfalfa, Laowangwheat and grass bromegrass were higher than that of their monoculture (P0.05N), but the nutritional value of Laomangmao and Laomao was lower than that of P0.05in monoculture. With the increase of the planting years of grassland, the yield component ratio and important value of alfalfa in mixed planting community increased obviously, and occupied the main position in the community, while the component ratio and important value of Laomangmao and bromegrass decreased year by year. There was no difference between the yield of mixed alfalfa grassland and monoculture alfalfa, but the yield of Laomangmao alfalfa mixed grassland was significantly lower than that of monocerne field P0.05. when the low stubble was 0 ~ 3 cm) or high frequency ~ 3 ~ 3 ~ (-1) / a), the yield of mixed alfalfa grassland was significantly lower than that of monoculture alfalfa field. Cutting twice a year was beneficial to the increase of grassland yield, but with the increase of cutting frequency, grassland yield decreased significantly (P 0.05). Mowing significantly increased the regeneration rate and annual total yield of alfalfa, but significantly decreased the regeneration ability of Laomangwheat and grass bromegrass, while 7~10cm stubble was beneficial to the regeneration of Laomangwheat and grass bromegrass, and decreased the yield of regenerated alfalfa. The yield of two mixed alfalfa meadows and monoculture alfalfa meadows was higher than that of single seeded Laomao wheat and single seeded bromegrass (P0.05) during cutting in full flowering stage of alfalfa. The yield component ratio and important value of alfalfa in mixed sowing grassland increased obviously with the delay of cutting time. The composition ratio and the important value of P0. 05 and P0. 05% were decreased obviously. The comprehensive evaluation results showed that the comprehensive production performance of mixed alfalfa grassland was the best, followed by single-seeded alfalfa grassland, and Laomangwheat alfalfa mixed grassland was lower than monoculture alfalfa, but superior to single seeded Laomangwheat and unicast grass brome. In addition, the composition of mixed alfalfa community in Laomangmao alfalfa was relatively stable than that in Laowangmao alfalfa. The optimum cutting time of the two mixed grassland was the flowering stage of alfalfa, the best frequency of cutting was 2 times per year, the yield and stability of alfalfa mixed cropping grassland was the best when stubble 7cm was retained, and the best 5cm was suitable in alfalfa field.
【学位授予单位】：内蒙古农业大学
【学位级别】：博士
【学位授予年份】：2015
【分类号】：S812
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本文编号：1977249