权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Studies on Development of High Productive Grazing System and Nitrogen Dynamics on Tropical-Subtropical Pasture

热带亚热带牧场高产放牧制度发展及氮素动态研究

基本信息

批准号：
14560227
负责人：
KAWAMOTO Yasuhiro
金额：
$ 2.05万
依托单位：
University of the Ryukyus
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2002
资助国家：
日本
起止时间：
2002 至 2003
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-14560227/
关键词：
Pasture Grazing system Giant stargrass Nitrogen dynamics パンゴラグラス放牧

项目摘要

The study was conducted firstly to clarify the potential carrying capacity of giant stargrass was evaluated under different stocking rates in intensive rotational grazing system. Secondly, the nitrogen dynamics through fertilization was estimated under different stocking rates with 15N tracer methods. The followings are the major results.1)Grazing trials were conducted to estimate a potential carrying capacity of giant stargrass based on the results which the optimum cutting frequency is 4-6 weeks and the effective nitrogen application level is 0.5 Nkg/a after cutting or grazing in giant stargrass grazing pasture. High pasture availability and good quality forage to bring about the effective animal production were produced by using relatively heavy stocking rates of 6-8 heads/ha.2)Annual ryegrass(Lolium multiflorum Lam.) was overseeded to heighten a nutritive production on the low productive giant stargrass pasture during short winter in this district. Pasture utilization and daily dry matter intake on the pasture overseeded with ryegrass were higher than pure giant stargrass. Average pasture availability and utilization at heavy stocking rate was higher than at light stocking rate even in winter.3)The fate of ^<15>N-labeled fertilizer nitrogen applied was estimated under two stocking. ^<15>N recovered by harvested part(same as intake part) was 10-43% through the year, and which value was higher under heavy stocking rate(6.4 heads/ha). ^<15>N recovered in soil was higher under light stocking rate(3.2 heads/ha).From the research, it can be concluded that the carrying capacity of giant stargrass pasture, managed effectively was doubled with increasing pasture and animal production comparing with the present traditional grazing system.

本研究首次明确了在集约化轮牧条件下，不同载畜率下星星草的潜在载畜量。其次，利用15 N示踪技术研究了不同放牧率下施肥对氮素动态的影响。主要研究结果如下：1）通过放牧试验，研究了大星草放牧草地的潜在承载力，结果表明，大星草放牧草地的最佳刈割频率为4-6周，有效施氮量为0.5Nkg/a。通过6-8头/公顷的相对高放牧率，生产出了高牧草利用率和高质量的牧草，从而实现了有效的畜牧生产。在该地区冬季较短的低生产力大星草草地上进行了补播，以提高其营养生产。覆种黑麦草的草地牧草利用率和日干物质采食量均高于单种巨星草。高放牧率下的草地利用率和草地利用率在冬季也高于低放牧率下。3）<15>估算了两种放牧率下施入的~（13）N-标记肥料氮的去向。全年<15>收获部分（与采食部分相同）的^ N回收率为10-43%，且在高放牧率（6.4头/ha）下的回收率较高。低<15>放牧率（3.2头/hm ~ 2）条件下，土壤氮的回收率较高。研究结果表明，在有效管理下，大星草草地的载畜量比传统放牧制度提高了一倍。