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51.
52.
基于矿物元素指纹图谱的黑龙江黄豆产地溯源 总被引:1,自引:0,他引:1
该研究探讨了矿物元素指纹分析技术对黑龙江黄豆产地溯源的可行性,筛选出判别黑龙江黄豆产地溯源的有效指标。利用电感耦合等离子体质谱仪(inductively coupled plasma mass spectrometry,ICP-MS)测定来自齐齐哈尔和北安2个地域50份黄豆样品中52种矿物元素的含量,并对数据进行了方差分析、主成分分析和判别分析。研究表明,46种矿物元素含量在地域间存在显著差异,通过逐步判别分析筛选出8项元素指标建立黄豆产地判别模型,所建立的模型对黄豆产地整体交叉检验判别率为95.7%。As、Ru、Gd含量在黄豆与土壤间呈显著正相关(P0.05),Tb含量在黄豆与土壤间呈极显著正相关(P0.01),由4种元素建立的判别模型对产地判别准确。因此,上述元素是黄豆矿物元素产地鉴别较可靠的指纹信息指标。 相似文献
53.
《African Journal of Range and Forage Science》2013,30(4):209-217
ABSTRACTLeaves and twigs from woody plants provide essential nutrients to range animals. We examined variation in the mineral status of 26 woody species, and the influence of harvesting height as well as the interactions of the main effects on minerals levels. Leaves were harvested from five individual plants per species at two height levels: low (<1 m) and upper (>1.5 m). For trees, all mineral levels showed variation (p < 0.05) between species. For shrubs and intermediate growth forms (between shrubs and trees), mineral levels except potassium (K) and zinc (Zn) were influenced (p < 0.05) by height × species interactions. Most browse species had calcium (Ca) contents (8.5–50 g kg-1) above the required levels, with the majority of the species having Ca beyond the maximum tolerable limit. Most browse plants had sufficient K, phosphorus, magnesium, manganese, iron and Zn concentrations to meet the requirements for ruminants. Copper was deficient in many browse leaves, thus supplementation should be considered in winter. We conclude that such knowledge is essential for sustainable use of browses as mineral supplements, especially during critical periods when climatic conditions limit the feed value of grasses. 相似文献
54.
先进的牧草种子收获和加工工艺及装备应用前景探讨 总被引:5,自引:0,他引:5
论述了牧草种子收获和加工特点、先进的加工工艺及先进的装备。在分析国内现状的基础上,提出了我国牧草种子收获和加工未来重点开发和研究的对象。 相似文献
55.
中国牧草品种审定工作的进展 总被引:20,自引:0,他引:20
回顾了全国牧草品种审定委员会自 1987年成立以来全国牧草品种审定工作的进展。到2 0 0 1年底已召开牧草品种审定会议 15次。通过审定登记的牧草、饲料作物、绿肥作物、水土保持植物和草坪草品种共 2 32个。其中育成新品种 93个 ,地方品种 39个 ,引进国外品种 6 2个 ,野生栽培品种 38个 ,包括禾本科牧草 5 2个种 118个品种 ,豆科牧草 34个种 92个品种 ,其他科包括苋科、藜科、菊科、蓼科、葫芦科和大戟科的 14个种 2 2个品种。文章介绍了牧草品种审定登记的标准 ,并对当前牧草品种审定工作中存的问题提出了改进的意见 相似文献
56.
Research on the disease called shimao zheng, which had resulted in widespread fleece-eating and shedding by sheep and goats in the Haizi area of Akesa County of Gansu Province of China, was carried out by both laboratory studies and pathological observations. There was a marked deficiency of sulfur in the wool and tissues of the affected animals. The pathological changes were mainly loss of fleece, exposure of the skin, keratinization of the epidermal cells, narrowing and reduced numbers of the fleece follicles, and fewer sebaceous glands and sweat glands. Histologically, there was atrophy of the striated and cardiac muscles and of the epithelium of the convoluted tubules of the kidney, together with a glomerulonephritis. The disease was considered to be a local nutritional and metabolic disorder, probably mainly caused by sulfur deficiency. 相似文献
57.
Implications of early selection for grain colour on iron and zinc content and productivity of common bean 下载免费PDF全文
Rita de Kássia Siqueira Teixeira Dayane Cristina Lima Ângela de Fátima Barbosa Abreu Magno Antonio Patto Ramalho 《Plant Breeding》2015,134(2):193-196
Brazilian consumers prefer beans of the beige grain colour. Common beans help supply dietary requirements for iron and zinc. The objectives of this study were (i) to determine whether early selection for grain colour affects the iron and zinc content and the grain yield in common beans and (ii) if an association between these characteristics was found, to obtain lines of carioca‐type grains with a high iron and zinc content and good grain yield. We evaluated 96 F3:4, F3:5 and F3:6 progeny at two locations for iron and zinc content and grain yield. We selected 48 progeny for grain colour and chose 48 others at random. We found that early selection for grain colour does not affect the zinc content and grain yield. A positive and high association was found between iron and zinc content, and both iron and zinc content were slightly negatively correlated with grain yield. It is possible to obtain common bean lines combining a high iron and zinc content with good grain yield as long as a selection index is used. 相似文献
58.
Soils that are forming on volcanic parent materials have unique physical and chemical properties and in most cases, on wet and humid climates, are classified as Andisols. The main purpose of this study is to examine if the soils that are forming on volcanic materials under a dry Mediterranean climate, in Nisyros Island (Greece), meet the requirements to be classified as Andisols. Soils from seven sites were sampled and examined for their main physico-chemical properties and selective dissolution analysis. Dithionite–citrate–bicarbonate (DCB) extractable Al and Fe (Áld, Fed), acid ammonium oxalate extractable Al, Fe, and Si (Álo, Feo and Sio), and sodium pyrophosphate extractable Al and Fe (Alp, Fep) were measured. In addition, Al and Si were determined after reaction with hot 0.5 M NaOH, (AlNaOH and SiNaOH) and with Tiron-(C6H4Na2O8S2), (AlT and SiT). P-retention was also measured. The soils are characterised by coarse texture, low organic matter content, low values of cation exchange capacity (CEC), and high pH values. Values of Sio, Alo and Feo are less than 0.022%, 0.09% and 0.35% respectively, highlighting the lack of noncrystalline components. The ratio (Fed–Feo)100/Fed is quite high expressing the degree of crystallisation of free iron oxides. For all samples tested, values of the Alo + 1/2Feo index are extremely low (< 0.24%). High SiNaOH and SiT (arising 2.76% and 2.18% respectively) indicate the presence of silica in amorphous forms. P-retention values are very low (< 12.6%). The results indicated the absence of noncrystalline minerals except for amorphous silica, and do not exhibit andic or vitric soil characteristics to be classified as Andisols. 相似文献
59.
Over-exploitation and rural growth have severely damaged native vegetations of Aravalli hills in Rajasthan, India. This study was conducted to evaluate the effects of different restoration practices (i.e., rainwater harvesting (RWH) and planting of tree seedlings) on improve- ment in soil water and nutrients and growth and biomass of herbaceous vegetation. Contour trench (CT), Gradonie (G), Box trench (BT), V-ditch (VD) and a control were imposed on 75 plots (each of 700 m 2 ) in natural slope gradient defined as <10%, 10% 20% and >20% slopes in 2005. Each plot had three micro-sites of 1-m 2 at up (USP), middle (MSP) and lower (LSP) part of the plot for observation in 2008. The existed gradient (due to soil texture and topographic features) of soil pH, EC, SOC, NH 4 - N, NO 3 -N and PO 4 -P in June 2005 between >20% to <10% slopes were decreased in 2008 after applying RWH techniques. Such improvement in soil status promoted vegetation growth and biomass in higher slope gra- dients. Soil water, species diversity and herbage biomass increased from USP to LSP, and RWH techniques had positive role in improving SOC, nutrients, vegetation population, evenness and growth at MSP. Despite of lowest SWC, regular rain and greater soil water usage enhanced green and dry herbage biomasses in 10% 20% and >20% slopes, compared with <10% slope. The highest diversity in CT treatment was related to herbage biomass, which was enhanced further by highest concentrations of SOC and PO 4 -P. Further, CT treatment was found to be the best treat- ment in minimizing biomass variance in different slopes. Conclusively, soil texture and topographic features controlled soil water and nutrients availability. Rainwater harvesting techniques increased soil water storage and nutrient retention and also enhanced vegetation status and biomass by minimizing the effects of hillslopes. Thus depending upon the site conditions, suitable RWH technique could be adopted to increase herb- age biomass while rehabilitating the degraded hills. 相似文献
60.
有机酸对高岭石, 针铁矿和水铝英石吸附镉的影响 总被引:12,自引:0,他引:12
Effects of organic acids (oxalic, acetic, and citric) on adsorption characteristics of Cadmium (Cd) on soil clay minerals (kaolinite, goethite, and bayerite) were studied under different concentrations and different pH values. Although the types of organic acids and minerals were different, the effects of the organic acids on the adsorption of Cd on the minerals were similar, i.e., the amount of adsorbed Cd with an initial solution pH of 5.0 and initial Cd concentration of 35 mg L^-1 increased with increasing concentration of the organic acid in solution at lower concentrations, and decreased at higher concentrations. The percentage of Cd adsorbed on the minerals in the presence of the organic acids increased considerably with increasing pH of the solution. Meanwhile, different Cd adsorption in the presence of the organic acids, due to different properties on both organic acids and clay minerals, on kaolinite, goethite, or bayerite for different pHs or organic acid concentrations was found. 相似文献