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本文就我国牧区资源特点,分析了牧区灌溉草业发展的持续能力及障碍因素,提出了我国牧区灌溉草业可持续发展主要举措:建立水、草、畜平衡发展体系;合理利用水资源,发展节水型灌溉;建立永久性人工饲草料基地;强化灌溉草业科研与科技推广力度等基本构想 相似文献
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Soaking can affect respirable dust particles and the concentrations of some nutrients in alfalfa and cool season grass hays. However, the effect of soaking on nitrates in hay has not been reported. The aim of this study was to evaluate the effects of soaking on teff hay, a warm season annual grass, that contained high concentrations of nitrate (>2.0%). Six bales of teff hay were used for the study. Six 0.5 kg samples were taken from each bale and assigned to one of six soaking treatments: no soaking (control), cold water immersion for 10 seconds, warm water immersion for 10 seconds, cold water soaking for 1 hour, warm water soaking for 1 hour, and cold water soaking for 8 hours. After soaking, hay was dried, ground, and submitted to a commercial laboratory for analysis. Data were analyzed by analysis of variance as a block design. When the main effect of treatment was significant (P < .05), means were separated by Tukey's honest significant difference test. Soaking for 1 or 8 hours decreased water-soluble carbohydrate (P < .0001). Phosphorus, potassium, sodium, and zinc concentrations were reduced by soaking for 1 hour or longer (P, K, Na: P < .0001; Zn: P = .003). Nitrate concentrations were reduced (P < 0.05) to safe levels for horses (≤0.5%) by soaking hay for 1 hour or longer but soaking also reduced the concentrations of some nutrients in the hay. Minimal differences were observed between cold and warm soaking temperatures. 相似文献
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青海省海北州是草资源较为丰富的地区,畜牧业经济在全州国民经济中占主导地位。通过调研,基本摸清了海北州草资源使用情况和存在的问题,并提出了相应的意见及建议,以期为海北州畜牧业发展再上新台阶奠定基础。 相似文献
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When a river overtops its flood banks, water running down the landward side of the bank can rapidly erode the soil surface and scour the bank, sometimes leading to breaches and collapse. A covering of living vegetation, particularly grass, can reduce this risk of water erosion. As part of a project to assess the effectiveness of different management regimes on bank vegetation cover, direct measurements were required of the erodibility of the soil surface. A portable erosion measurement device (EMD) was developed by LAB Coastal with the support of the Environment Agency. This could direct water flowing at known velocities across areas of the flood banks, and it was used to test directly the erosion resistance of vegetated grass banks at three sites. The EMD gave a direct measure of the erodibility of a small sample of flood bank. While measurements of soil strength and assessments of vegetation cover were useful, they did not always correctly characterize the stability of the bank surface as measured directly by the EMD. The EMD and its use are described and the results obtained are discussed. The results indicate that flood banks need to be mown at least once a year to make them less vulnerable to erosion. 相似文献
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为研究谷氨酸铜制剂对罗非鱼、草鱼的生长性能、血清生化指标和鱼体组成的影响,选用180尾罗非鱼、135尾草鱼,分别随机分为3个处理组,每组3个重复,每个重复20或15尾。在基础饲料中添加五水硫酸铜作为对照组(10 mg/kg),试验组添加谷氨酸铜(高、低剂量组分别为10、5 mg/kg,按铜离子计),饲养8周。结果表明:与对照组相比,谷氨酸铜高、低剂量组罗非鱼的增重率分别提高3.9%和5.8%,草鱼的增重率分别提高4.0%和5.9%;罗非鱼特定生长率分别提高1.9%和3.3%,草鱼分别提高2.5%和3.5%;罗非鱼和草鱼的平均饵料系数分别降低7.6%和3.7%。两种鱼的血清生化指标及体组成各试验组间均无显著差别(P>0.05)。由此可见,日粮中添加适量谷氨酸铜可提高鱼体的生长性能,且效果优于五水硫酸铜。 相似文献
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