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61.
王文跃 《安徽农业科学》2013,41(1):166+190-166,190
在分析吉林省西部地区生态和气象生长条件对牧草影响的基础上,利用最优二分割技术,根据农业气候相似原理,对吉林省西部地区牧草适宜生长区域进行了划分。结果表明,大安、前郭、松原、长岭、扶余为牧草最适宜生长区,白城、镇赉、洮南、乾安为次适宜生长区,通榆为较适宜生长区。  相似文献   
62.
喷施叶面肥是提高苜蓿产草量和品质的有效措施之一。为探明不同叶面肥成分对紫花苜蓿(Medicago sativa L.)生长、产草量和品质的影响,并筛选紫花苜蓿优质高产的叶面施肥方案,本试验以生长第2年的‘东农1号’紫花苜蓿(Medicago sativa L.‘Dongnong No.1’)为材料,在春季返青期一次性土壤施肥基础上,于刈割前20天分别喷施苜蓿专用叶面肥(自主研制,专利申请号:201810124670.2)、0.3%尿素、0.5%磷酸二氢钾、0.3%尿素+0.5%磷酸二氢钾、0.3%尿素+0.1%硫酸亚铁+0.05%钼酸铵、0.5%磷酸二氢钾+0.1%硫酸亚铁+0.05%钼酸铵,0.3%尿素+0.5%磷酸二氢钾+0.1%硫酸亚铁+0.05%钼酸铵这7种叶面肥(分别简称叶面肥A,B,C,D,E,F,G),以喷施清水为对照,每年刈割3茬,观测不同叶面肥对‘东农1号’紫花苜蓿高度、茎叶比、产草量和营养品质的影响,并进行经济效益比较分析。结果表明:喷施叶面肥均可显著提高紫花苜蓿垂直高度、产草量和粗蛋白含量;其中叶面肥G处理下,全年总干草产量达14 595.81 kg·hm-2,比对照提高17.70%;平均粗蛋白含量为25.43%,比对照提高3.12%。叶面肥A处理纯增经济效益和产投比分别达2 414.57元·hm-2和2.63,是叶面肥G处理的2.65倍和8.77倍。经过综合比较分析,在寒地黑土农区喷施紫花苜蓿专用叶面肥(A处理)相对投入较少,产出较多,综合效益最高。  相似文献   
63.
针对巴基斯坦高温干旱的自然条件及高填方高速公路边坡土壤高盐碱、贫瘠、板结等特点,通过添加有机质(甘蔗渣、河泥)、腐殖酸、脱硫石膏等改善土壤理化性质,并通过实地调查,选择适宜该地栽培的草本种类及种植方式进行边坡植草。结果表明:在土壤中加入甘蔗渣和河泥可以有效的改善土壤板结情况,最佳施用比例为50%原状土+20%甘蔗渣+30%河泥;在土壤中加入腐殖酸和脱硫石膏可有效的降低土壤pH值,降低土壤盐碱度,最佳配比为0.5kg/m^2腐殖酸+8kg/m^2脱硫石膏;在土壤中加入磷酸二铵可有效的增加土壤中氮磷含量,最佳添加量为22.5g/m^2。通过沿线物种调查,优选出高抗性本地品种狗牙根,并通过对比试验得出最佳种植方式为条植。该研究对于巴基斯坦高填方公路边坡绿化防护具有积极的现实意义及广阔的推广前景。  相似文献   
64.
污泥复混肥对早熟禾草坪草生长性状及土壤酶活性的影响   总被引:3,自引:0,他引:3  
为使城市生活污泥得以无害化、资源化综合利用,通过盆栽试验,研究了经无害化处理的生活污泥辅以化肥配制的污泥复混肥对早熟禾草坪草生长以及土壤酶活性的影响.结果表明:在氮、磷、钾施用总量相同的条件下,随复混肥中污泥含量的增加,草坪土壤脲酶、蛋白酶、转化酶活性显著提高,草坪草的颜色明显改善,剪草量、分蘖数显著增加,特别在生长中后期草坪颜色提高两个等级,剪草量鲜重增加10~15g·盆-1,分蘖数增加30~50个·盆-1,细胞膜透性降低40%.但污泥提供氮素养分占总氮量的60%以上时,其肥料效应的增加不再显著,故在配制污泥复混肥时,以污泥提供氮素养分占总氮量的60%左右为宜.  相似文献   
65.
针对宁夏半干旱区7龄以上苜蓿(Medicago sativa)草地退化导致的牧草产量低、品质差等问题,本试验采用单因素随机区组设计,研究了多年生黑麦草(Lolium perenne)、披碱草(Elymus nutans)、苇状羊茅(Festuca arundinacea)、无芒雀麦(Bromus inermis)、鸭茅(Dactylis glomerata)补播对退化草地苜蓿主要农艺性状和牧草品质的影响,并利用主成分分析方法(PCA)评价其改良效果。结果表明:补播禾草对苜蓿株高、叶茎比、一级分枝数和干草产量均有显著影响(P<0.05),其中,补播苇状羊茅干草产量最高,其次为多年生黑麦草和无芒雀麦;补播禾草对牧草粗蛋白、粗脂肪、粗灰分、中性洗涤纤维和酸性洗涤纤维含量有显著影响(P<0.05);PCA分析得出,补播鸭茅、苇状羊茅综合性状分别排第一、二位。因此,可根据不同改良目的选择不同禾草种类进行补播,苇状羊茅可显著提高退化苜蓿草地生产性能,补播鸭茅可显著改善退化苜蓿草地牧草品质。  相似文献   
66.
唐芳林  杨智  王卓然  孙暖  韩丰泽  赵金龙 《草地学报》2021,29(11):2381-2390
草原是我国面积最大的陆地生态系统,既是我国重要的生态安全屏障,也是广大农牧民赖以生存的家园。为深入贯彻习近平生态文明思想,落实山水林田湖草沙系统治理的理念,推进草原保护修复和高效利用,本研究结合"十四五"林业和草原保护发展规划纲要,提出了构建草原监测评价体系、草原保护体系、草原生态修复体系、草原执法监管体系、现代草业体系、支撑保障体系等草原治理体系,旨在为推进草原治理体系和治理能力现代化提供参考。  相似文献   
67.
Recently, there has been a renewed interest and an increase in published research on equine grazing and pasture management. The objectives of this paper are to review equine grazing research methodologies with an aim to encourage standardized research procedures. This review highlights standard methods used in equine pasture-related research, including use of climate data and soil type; seed bed preparation and grazing management; determining forage nutritive value; defining forage maturity; tracking horse health parameters; evaluating different grazing systems; and future technologies. This review covers in-depth discussions on determining forage biomass yield, forage populations, ground cover, persistence, forage intake, and grazing behavior. Specifically, mechanical harvesting, hand clipping, rising plate meter, and falling plate meter are all methods used to determine forage biomass yield. Frequency grid, point sampling, visual assessment, Natural Resources Conservation Service pasture condition score, and the double Dominant, Abundant, Frequent, Occasional, Rare (DAFOR) scale can be used to track forage populations, ground cover, and persistence of pasture species. Three primary methods have been used when estimating horse forage intake including the difference between pre- and postgrazing herbage mass, the difference in pre- and postgrazing bodyweight, and use of digestibility and fecal output markers. Equine grazing behavior has been described by investigating preference, pre- and post-sward height, and bite and mastication rate. Awareness of key methodologies should encourage movement toward research protocol standardization that will allow for scientific comparisons and application of pasture-related research results across the horse industry.  相似文献   
68.
徐建 《青海草业》2008,17(1):32-36
本文以青海草业科技人员2006年在《草业学报》、《草地学报》等8种中文期刊中发表的论文为统计源,运用文献计量学方法对文后所附参考文献的引用文献类型、语种、年代及被引期刊论文密度及主要期刊分布等项内容进行统计分析,探讨了本省草业科技人员利用文献的一般规律,提出了加强专业图书馆(室)文献建设的措施、建议。  相似文献   
69.
It has been shown that the cis 9, trans 11 isomer of conjugated linoleic acid (CLA) can be increased in milk by supplementation with fish oil and vegetable oils. Feeding a high level of oil, however, can impact negatively on gross milk composition. The principal aim of this study was to determine if relatively low levels of fish oil or sunflower oil, either alone or in combination, offered to dairy cows on pasture would increase the C18:2 cis 9, trans 11 CLA concentration in milk. Forty autumn-calved cows on a diet of grazed grass were assigned to 4 supplementation treatments: (i) No supplement (P), (ii) 255 g/day of sunflower oil (SO), (iii) 255 g/day of sunflower oil + 52.5 g/day of fish oil (SOFO), and (iv) 105 g/day of fish oil (FO). The fish oil was supplied in a proprietary product called Omega-3 Supplement which is a mixture of marine oils and an extracted oilseed meal and contains 500 g/kg of oil. The oils were fed in a concentrate mixture, which was offered at a rate of 3.0 kg/cow per day. The production of the cows was measured for 54 days and the milk fatty acid composition was determined on day 0 (immediately before the supplements were introduced) and on days 14, 28 and 42 after the treatments were imposed. Supplementation increased the yield of milk (P < 0.01), protein (P < 0.05) and lactose (P < 0.001), decreased milk fat (P < 0.05) and protein (P < 0.01) concentrations and increased (P < 0.01) lactose concentration. Type of oil did not significantly affect any production variable. The concentration of C18:1 trans 9 + C18:1 trans 11 (mainly C18:1 trans 11) (P < 0.001) and C18:2 cis 9, trans 11 CLA (P < 0.01) were greater on supplemented treatments than on P and the concentration of both were greater (P < 0.05) on FO than on SO. The results confirm that the concentration of C18:2 cis 9, trans 11 CLA can be increased further, from an already relatively high concentration in milk from pasture, by offering supplements containing a low level of fish oil either alone or in combination with sunflower oil.  相似文献   
70.
The objective of this study was to investigate the effect of daily herbage allowance and concentrate supplementation level offered at approximately 40 and 80 days in milk (DIM) and the carryover effects at 120 DIM on the production performance of spring calving dairy cows. Sixty-six (30 primiparous and 36 multiparous) Holstein–Friesian dairy cows (mean calving date — 7 Feb ± 9.9 days) were randomly assigned to a 6 treatment (n = 11) grazing study. The experiment was a randomised block design with a 3 × 2 factorial arrangement of treatments (3 daily herbage allowances (DHA's; approximately 13, 16 and 19 kg DM/cow/day; > 4 cm) and 2 concentrate allowances (0 and 4 kg DM/day). Treatments were imposed from 21 February to 8 May. Following this period (subsequent 4-weeks) animals were offered a daily herbage allowance of 20 kg DM/cow/day and no concentrate. Milk production, total dry matter intake (TDMI), energy balance (EB) and blood metabolites were measured on three occasions — at approximately 40, 80 and 120 days in milk, R1, R2 and the carryover period, respectively. Cows offered a low DHA had a lower post-grazing sward height but increased sward utilisation (> 4 cm) during R1 and R2, there was no difference during the carryover period. Concentrate supplementation increased post-grazing sward height by 11% during R2 but had no effect during R1 and the carryover period. Daily herbage allowance had no effect on milk yield or composition during R1 however a low DHA tended to reduce milk yield in R2. Concentrate supplementation increased milk and solids corrected milk (SCM) yield by 4.1 and 2.8 kg/cow/day, respectively during R1 and also increased R2 milk production performance, this effect extended into the carryover period. Offering a low DHA restricted grass dry matter intake (DMI) during R1 and R2 yet concentrate supplementation significantly increased total DMI (2.3 (R1) and 3.0 (R2) kg DM/cow). Animals offered a low DHA had a significantly lower bodyweight (BW) than those offered a medium or high DHA during P1 and P2. Concentrate supplementation increased BW during P1 and P2 (+ 9 and + 14 kg/cow, respectively). There was no effect of treatment on BW during P3. There was no effect of DHA on EB in R1; during R2 animals offered a low DHA had the lowest EB. Concentrate significantly increased EB in R1 and R2 and increased plasma glucose concentration while it decreased plasma NEFA and BHB concentrations. The results of this study indicate that animals should be offered a low DHA up to 80 DIM after which DHA should be increased however animals should also be supplemented with concentrate during the early post-partum period.  相似文献   
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