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81.
Revegetation of copper mine tailings with ryegrass and willow 总被引:12,自引:0,他引:12
To restore vegetation on metal mine tailings is very difficult because they often contain high concentrations of heavy metals, low nutrient content and low water retention capacity. This study involved 3 experiments that evaluated the effects of 4 treatment amendments: montmorillonite, rice straw, organic manure and chemical fertilizer on the growth of ryegrass (Loliurn perenne L.) and willow (Salix virninalis L.) with Cu and Zn mine tailings from two mining areas. The results showed that ryegrass was the most tolerant of 4 crops to Cu toxicity. Also when organic manure, which contained high concentrations of inorganic salts, was added to the mine tailings, it significantly hindered ryegrass growth (P=0.05).Meanwhile, with ryegrass organic manure significantly increased (P=0.05) the extractable Cu concentration in both mine tallings. When montmorillonite was used as a mine tailings amendment with willow, the height and tress number at the 1st cut were significantly greater (P = 0.05) than a control without montmorillonite. However there was no significant difference for height, tress number, dry weight or root dry weight at the 2nd cut. So, amendment applications to reduce metal toxicity and increase nutrients retention in mine tailings were essential during revegetation of mine tailings. 相似文献
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Sulfonamide antibiotics reach soil via manure and adversely affect microbial diversity. Clear effects of these bacteriostatic, growth‐inhibiting antibiotics occur in the presence of a parallel input of microbial activity stimulating manure. Natural hot spots with already increased soil microbial activity are located in the rhizosphere, comprising microorganism such as Pseudomonas with plant growth promoting and pathogenic strains. The hypothesis was therefore that the antibiotic activity of sulfonamides is promoted in the rhizosphere even in the absence of manure, followed by shifts of the natural plant‐specific microbial community structure. This was evaluated by a laboratory experiment with Salix fragilis L. and Zea mays L. After 40 d of incubation, sub‐areas such as non‐rhizosphere soil, rhizosphere soil and plant roots were sampled. Effects on microbial community structure were analyzed using 16S rRNA gene fragment patterns of total bacteria community and Pseudomonas. Selected exoenzymes of N‐, P‐, and C‐cycling were used to test effects on microbial functions. Compared to the factors soil sub‐area and sulfadiazine (SDZ) content, plant species had the largest influence on the bacterial community structure and soil exoenzyme activity pattern. This was also reflected by an up to 1.5‐fold higher acid phosphatase activity in samples from maize‐ compared to willow‐planted soil. We conclude that antibiotic effects on the bacterial community structures are influenced by the antibiotic concentration and root influence. 相似文献
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85.
半干旱风沙区黄柳幼苗生长发育对沙埋的响应 总被引:1,自引:0,他引:1
以科尔沁沙地黄柳(Salix gordejevii)幼苗为研究对象,通过0 cm,10 cm,20 cm和40 cm 4个沙埋处理,研究其生长发育对沙埋的响应。结果表明:随着沙埋深度的增加,黄柳幼苗的死亡率增加,存活率下降。沙埋对黄柳幼苗的株高、相对高度增长率,分配到根、茎、叶的生物量和根冠比有显著影响,对绝对高度增长率和生物量无显著影响。轻度沙埋有利于黄柳幼苗高度增加,随着沙埋深度的增加,株高依然增加,相对高度生长率却下降。轻度沙埋使黄柳幼苗的生物量较多地分配到根,随着沙埋深度的增加,较多的生物量分配给地上部分,根冠比下降。说明黄柳幼苗可通过加快茎的生长或改变生物量的分配等方式维持光合作用能力,增加对沙埋的抵御能力。 相似文献
86.
BACKGROUND: The tyrosine to cysteine amino acid substitution at location 139 of the vkorc1 protein (i.e. tyrosine139cysteine or Y139C) is the most widespread anticoagulant resistance mutation in Norway rats (Rattus norvegicus Berk.) in Europe. Field trials were conducted to determine the incidence of the Y139C mutation at two rat‐infested farms in Westphalia, Germany, and to estimate the practical efficacy against them of applications, using a pulsed baiting treatment regime, of a proprietary bait (Klerat?) containing 0.005% brodifacoum. RESULTS: DNA analysis for the Y139C mutation showed that resistant rats were prevalent at the two farms, with an incidence of 80.0 and 78.6% respectively. Applications of brodifacoum bait achieved results of 99.2 and 100.0% control at the two farms, when measured by census baiting, although the treatment was somewhat prolonged at one site, possibly owing to the abundance of attractive alternative food. CONCLUSION: The study showed that 0.005% brodifacoum bait is fully effective against Norway rats possessing the Y139C mutation at the Münsterland focus and is likely to be so elsewhere in Europe where this mutation is found. The pulsed baiting regime reduced to relatively low levels the quantity of bait required to control these two substantial resistant Norway rat infestations. Previous studies had shown much larger quantities of bromadiolone and difenacoum baits used in largely ineffective treatments against Y139C resistant rats in the Münsterland. These results should be considered when making decisions about the use of anticoagulants against resistant Norway rats and their potential environmental impacts. Copyright © 2012 Society of Chemical Industry 相似文献
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88.
宝兴鼠尾草的有效成分提取及含量测定 总被引:1,自引:0,他引:1
采用超声提取法、回流提取法及索氏提取法对宝兴鼠尾草有效成分的提取效果进行比较,并采用高效液相色谱法(HPLC)对所提取成分含量进行测定,并与栽培丹参的相应成分进行比较.结果表明:对于样品中的脂溶性成分,超声提取法以低温、高效的特点明显优于其他2种方法;而对于水溶性成分,索氏提取4h的效果更佳;对其含量分析表明,宝兴鼠尾草的脂溶性成分含量较高,其中丹参酮IIA的含量达到枟中国药典枠规定,但水溶性成分含量偏低.说明宝兴鼠尾草具有一定的药用价值,但能否作为丹参代用品有待进一步研究. 相似文献
89.
[目的]建立湖北麦冬叶片的快繁体系。[方法]以湖北麦冬幼嫩叶片为外殖体,以MS为基本培养基,向其中添加不同浓度的6-BA、NAA、GA后进行培养,探讨外源激素对其愈伤形成、不定芽分化、增殖与不定根形成的影响。[结果]采用MS+0.1~2.0 mg/L 6-BA+0.01~0.5 mg/L NAA培养基,愈伤诱导率在20%以上;采用MS+0.1~1.0 mg/L 6-BA+0.01~0.5 mg/LNAA+0.1~1.0 mg/L GA培养基,对芽的生长及增殖效果好,说明GA具有提高成苗率的作用;采用1/2MS+0.1~0.5 mg/L NAA或0.1 mg/L IBA或0.1~0.5mg/L IAA,20 d内生根率可达97%以上。在腐叶土∶珍珠岩=5∶3的基质中驯苗,成活率可达90%以上。[结论]优选出了湖北麦冬叶片的最佳快繁体系,为麦冬的开发利用提供了理论依据。 相似文献
90.
本试验旨在探讨注射地塞米松(DEX)模拟应激状态下,应激和饲粮能量水平对肉仔鸡能量采食的影响。选取体重相近的180只23日龄的雄性爱拔益加(AA)肉鸡随机分成6组,每组3个重复,每个重复10只鸡。试验采用2×3析因设计,因素为DEX[处理(注射DEX2 mg/kg)、未处理(注射等剂量生理盐水)]和饲粮能量水平[高能(HE)、低能(LE)以及高能、低能自由采食(H-LE)]。预试期5 d,正试期7 d。结果表明:1)DEX处理极显著降低了肉仔鸡的采食量和体增重(P<0.01),极显著提高了耗料增重比、耗能增重比、腹脂率以及血浆葡萄糖、甘油三酯和尿酸的浓度(P<0.01),显著提高了肠道指数(P<0.05)。2)采用LE饲粮体增重(P<0.05)、腹脂率(P<0.01)显著低于其他2种饲粮,耗料增重比显著低于HE饲粮(P<0.05);采用HE饲粮耗能增重比极显著高于其他2种饲粮(P<0.01);采用H-LE饲粮神经肽Y(NPY)基因表达量显著高于LE饲粮(P<0.05)。3)DEX、饲粮能量水平对耗料增重比(P<0.05)和耗能增重比(P<0.01)的影响存在显著的互作效应。结果提示,DEX应激可使肉仔鸡血浆中葡萄糖、尿酸和甘油三酯的浓度升高;DEX应激和HE饲粮均能增加脂肪在腹部沉积,提高耗料增重比和耗能增重比;H-LE饲粮能上调肉仔鸡下丘脑NPY基因表达。 相似文献