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排序方式: 共有141条查询结果,搜索用时 15 毫秒
1.
为探究蚯蚓粪与化肥配施对陕西关中地区红小豆产量及品质的影响,以红小豆新品种保红947为研究对象,设置T1(纯化肥)、T2(20%蚯蚓粪+80%化肥)、T3(50%蚯蚓粪+50%化肥)、T4(80%蚯蚓粪+20%化肥)和CK(不施肥)5个处理,研究了不同处理下红小豆成熟期农艺性状、产量性状及品质性状的差异.结果表明:蚯蚓...  相似文献   
2.
Copper(Cu)-based fungicide application to control foliar diseases in grapevine(Vitis vinifera L.) can increase soil Cu availability. Brazilian soils have high natural Cu and manganese(Mn) concentrations, increasing the potential for toxicity to grapevine plants. Application of amendment substances can reduce the concentrations of toxic chemical species of Cu and Mn in soil solution, especially for the soils grown with young plants. We evaluated the chemical speciation of Cu and Mn in soil soluti...  相似文献   
3.
Application of organic fertilizers in sustainable agriculture systems improves yield sustainability of field crop production. The current research has been formed to investigate the effects of various levels of vermicompost (zero, 3, 6 and 9 t ha?1) in combination with foliar spraying of potassium humate (0, 1, 2 and 3 mL L?1) on spring safflower, in Iran during 2012–2013. In addition, inorganic fertilization has been considered as conventional agriculture (CA). In the current experiment, growth indices, seed yield, yield components and flower yield were evaluated. The results showed that the maximum leaf area index, total dry weight and crop growth rate have been determined at 9 t ha?1 vermicompost and 3 mL L?1 K-humate while the maximum netto assimilation rate has existed in CA at the emergence of flower buds. Likewise, the results indicated that vermicompost leads to a significant increase in seed yield, flower yield and yield components except 1000 seed weight. Flower yield, head number per plant and seed number per head were affected by K-humate concentrations and increased significantly from 1 to 3 mL L?1. It should be mentioned that 9 t ha?1 vermicompost and 3 mL L?1 K-humate produced the highest seed and flower yield.  相似文献   
4.
Present investigation evaluates the effect of organic fertilization (OF), integrated nutrient management (INM) practice, and recommended dose of chemical fertilization (CF) on changes in soil organic phosphorus (P) and its fractions under rice (Oryza sativa L.)–wheat (Triticum aestivum L.) cropping system. The 4-year experiment (2009–2013), under split-plot design, showed that OF did not increase the total P or total organic P content of soil under either of the test crops. However, OF maintained the higher level of labile organic P and moderately labile organic P in soil under wheat the moderately stable organic P and highly stable organic P was highest in paddy soil under CF practices (11.34 and 7.77 μg g?1, respectively) followed by wheat. The P concentration in organically grown rice or wheat grain was increased significantly compared with their CF counterparts. The productivity economics for rice and wheat crops showed INM fertilization to be more economical than OF.  相似文献   
5.
Soil organic matter (SOM) plays an important role in the Se dynamics in soil. The potential effects of vermicompost and digestate as important sources of SOM on selenium (Se) mobility were assessed in this study. Three soils differing in their physicochemical parameters, fluvisol, chernozem, and luvisol, were chosen, and three types of vermicomposts based on various bio-waste materials as digestate (vermicompost 1), kitchen waste with woodchips (vermicompost 2), and garden bio-waste (vermicompost 3) were used due to their high organic matter content. Additionally, digestate samples alone were applied. To evaluate the potential effect of vermicompost application on sorption characteristics of soils, batch sorption experiments were performed. The results showed a predominant effect on Se species in the soils, where selenite sorbed more intensively compared to selenate, regardless of the soil and ameliorative material applied. In the control, the soil sorption ability of selenite tended to decrease in the order:fluvisol > luvisol > chernozem. However, these differences were not significant. Moreover, the effects of the ameliorative materials depended on both soil and amendment used. In fluvisol, all the amendment applications resulted in a decrease in distribution coefficient (Kd values) of Se, whereas in chernozem, this effect was observed only for the digestate-based vermicompost 1. Increasing Kd levels were reported in luvisol treated with digestate; the application of garden bio-waste-based vermicompost 3 tended to decrease the Kd values. Further studies are required on long-term effects of these amendments on Se mobility in soils and the role of individual organic matter fractions in this context.  相似文献   
6.
The aim of this work was to study the effects of vermicomposting on selected properties of composts derived from animal and plant wastes. For this, two different worm beds were established and fed with two composts: C1, made from goat (Capra aegagrus hircus) manure and rosemary (Rosmarinus officinalis) pruning wastes, and C2, made from rabbit (Oryctolagus cuniculus) manure and grass clippings, to study the quality of the final vermicomposts. Physical and chemical properties were determined in the end products. Vermicomposting improved several properties of the composts, increasing their total water-holding capacity (in C1, from 333 to 451 mL/L, and in C2, from 371to 419 mL/L), reducing salinity (in C1, from 6.8 to 2.4 dS/m, and in C2, from 10.3 to 4.6 dS/m), and balancing pH in the final composts obtained, especially in C1 (from 8.57 to 8.02). The type of raw material used in the worm beds significantly influenced the final characteristics of the end products obtained and the development of the process, with more favorable results being obtained with the compost derived from rabbit manure and grass clippings (C2).  相似文献   
7.
[目的]探讨蚯蚓粪与化肥配施对西瓜种植的作用,为土壤培肥制度的建立及西瓜生产提供参考。[方法]以"黑彤K-8"为试材,通过大田试验研究了N100(尿素提供100%的氮)、M10N90(蚯蚓粪和尿素分别提供10%和90%的氮)、M30N70(蚯蚓粪和尿素分别提供30%和70%的氮)和M50N50(蚯蚓粪和尿素各提供50%的氮)等不同处理对土壤活性有机碳、碳库管理指数(CPMI)、酶活性和西瓜产量的影响。[结果]同N100处理相比,配施蚯蚓粪处理的高活性、中活性和活性有机碳含量均明显升高;M30N70处理的活性有机碳含量和CPMI显著高于其他处理,比N100处理分别高出30.10%和37.28%;同时,脲酶和蔗糖酶活性亦明显高于其它处理,其中蔗糖酶活性分别较CK,N100,M10N90和M50N50处理提高84.66%,62.33%,47.26%和22.46%。此外,M30N70处理的西瓜产量和肥料生产率最高,它可使西瓜产量分别比N100,M10N90和M50N50处理高出26.49%,13.34%,6.27%;M30N70处理的肥料生产率分别比N100,M10N90和M50N50处理高出166.50%,54.11%,21.37%。相关分析结果表明,运用土壤活性有机碳和碳库管理指数表征土壤酶活性、西瓜产量及肥料生产率的变化,比土壤总有机碳更具灵敏性。[结论]蚯蚓粪与化肥配施对西瓜生长具有显著的促进生长效果,其中3∶7比例配施的效果优于1∶9和5∶5比例。  相似文献   
8.
针对农田土壤镉(Cd)活性高的问题,以寻求具有良好重金属钝化特性的原位修复材料为目标,该研究以铁粉、磷矿粉和牛粪混合蚯蚓堆肥所制备的矿物基蚯蚓粪为研究对象,利用系列结构表征手段对其进行基本性质表征,并进一步分析矿物基蚯蚓粪施加下土壤对Cd吸附、有效性和赋存形态的影响,最终筛选出具有良好Cd钝化效果的矿物基蚯蚓粪。结果表明,铁粉及磷矿粉的添加使矿物基蚯蚓粪中的pH值、C/N、有机质含量有所降低,但总养分含量显著增加(P<0.05)。比表面积及孔隙度、扫描电镜分析和X射线能谱分析结果表明,矿物质的添加增大了蚯蚓粪比表面积和孔容,改变了蚯蚓粪中矿物元素的占比。傅立叶变换红外光谱分析表明,矿物基蚯蚓粪中醇或羧酸类、芳香类以及多糖类物质增多,脂类和碳水化合物减少。X射线衍射分析表明,添加铁粉及磷矿粉制备出来的矿物基蚯蚓粪增加了磷酸盐、纳米零价铁等矿物组分。土壤培养和吸附解吸试验表明,施加矿物基蚯蚓粪显著提升了土壤对Cd的吸附强度,降低了对Cd的解吸率,其中以牛粪+20%铁粉+20%磷矿粉(VCFe+P)进行蚯蚓堆肥所获得的矿物基蚯蚓粪处理的土壤对Cd的吸附效果最佳,较施加纯蚯蚓粪的土壤吸附...  相似文献   
9.
ABSTRACT

Field experiments were conducted for 2 years in sandy loam soil, to study the direct effect of organic manures i.e. sewage sludge (SS), vermicompost (VC) and sesbania (SB) and chemical fertilizers on rice (Oryza sativa) and their residual effect on wheat (Triticum aestivum) grown in sequence in winter (Rabi) and summer (Kharif) season during 2015–2016 to 2016–2017 at Varanasi, Uttar Pradesh. Residual effect of organic sources of nutrients as SS, VC and SB were monitored up to fourth crop (II wheat) in sequence applied in conjunction with 75% recommended dose of fertilize (RDF). Among the nutrient sources, the maximum grain yield in I rice (4.89 t ha?1), II rice (4.95 t ha?1), was recorded in treatment T3 (100% RDF with S, Zn, B) whereas in I wheat (4.68 t ha?1) and II wheat (4.59 t ha?1), it was recorded in T4 (customized fertilizer). The maximum straw yield during all four crops was recorded in T3 (100% RDF with S, Zn, B) in rice and T4 (customized fertilizer) in wheat crop, which showed 25, 32, 23 and 28% increase over 100% RDF (T2). Application of 100% RDF along with S, Zn, B and customized fertilizer increased the total uptake of N, P, K, S and B and also in net returns and B:C ratio followed by organic treatments.  相似文献   
10.
A 2-year field study was conducted to evaluate the effect of two organics, farmyard manure and vermicompost, each at three rates (0, 5, 10 t ha?1 and 0, 1, 2 t ha?1, respectively), along with two levels of mineral fertilizer (75% and 100% of recommended dose), on crops yields and soil properties under a wheat–fodder maize cropping sequence. Individual addition of organics at a higher level increased yields of wheat and subsequent maize. Soil microbial biomass carbon was enhanced as both a direct and residual effect with the addition of farmyard manure followed by vermicompost and fertilizer treatments, and also by combined addition of manure with either vermicompost or mineral fertilizer. Farmyard manure increased the availability of soil macro- and micronutrients, whereas vermicompost influenced only the availability of micronutrients at wheat harvest. A residual effect of farmyard manure and mineral fertilizers was found for available N. Meanwhile, the residual status of micronutrients in the soil was either maintained or significantly improved due to organic amendments (Mn and Zn with farmyard manure; Fe and Zn with vermicompost). Interaction of farmyard manure and vermicompost at a higher level benefited the next crop by increasing the yield of fodder maize and improving the availability of P and metals in soil.  相似文献   
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