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21.
低温复合菌剂对牛粪堆肥发酵影响的研究 总被引:10,自引:2,他引:8
为了探明低温复合菌剂对牛粪堆肥发酵的影响,开发出适合东北寒区堆肥发酵的微生物菌剂.本研究在0℃以下以牛粪、秸秆为原料,分别设置接种低温复合菌剂堆肥、接种常温菌剂堆肥和自然堆肥3个处理,测定了堆肥过程中温度、p H、C/N、全磷、铵态氮、硝态氮和种子发芽指数的动态变化.试验结果表明,接种低温复合菌剂组第11 d进入高温期(50℃),比接种常温菌剂组提前了14 d,最高温度达62℃,高温期维持了9 d,而自然堆肥组一直未进入高温期.至堆肥结束时,接种低温复合菌剂组和接种常温菌剂组的最终p H分别为7.17、7.24;C/N均降到20以下,分别为16.10、15.67;全磷的变化无明显差异;种子发芽指数分别为92%和85%.添加菌剂组较自然堆肥组铵态氮含量明显降低,硝态氮含量增高.综上所述,接种低温复合菌剂可以在低温下促进堆肥迅速起温,并保证了堆肥的腐熟质量. 相似文献
22.
畜禽养殖业是"十二五"期间氨氮总量减排的重点,其清洁生产与末端治理技术种类繁多,不同技术在不同应用条件下减排效果差别显著。深入分析了国内外畜禽养殖业发展与污染现状,系统归纳了国内畜禽养殖业氨氮总量减排技术区域特征,综合使用层次-灰色综合评判法、费用-效益法、表单法等对氨氮总量减排技术进行了综合性的评价研究,构建了基于面向服务架构(SOA)的氨氮减排技术评估咨询平台。结果表明,氨氮总量减排技术评估方法与平台可大幅度提高技术评价的效率和精确度,可广泛应用于企业和管理部门氨氮减排的工程技术与环境管理工作。 相似文献
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24.
采用综合污染指数法对锦州市农村两家畜禽养殖场区周边土壤监测数据进行评估,分析了畜禽粪便对畜禽养殖场周边土壤中重金属污染的影响。 相似文献
25.
羊粪生物炭对水体中诺氟沙星的吸附特性 总被引:3,自引:0,他引:3
以羊粪为原料分别在350、450、550、650℃条件下制备生物炭,通过元素分析、BET-N_2、电镜扫描及FTIR表征了不同热解温度下羊粪生物炭的结构特征,并采用序批实验研究了pH、生物炭投加量、热解温度、初始浓度等因素对羊粪生物炭吸附水体中诺氟沙星(NOR)的影响及吸附机制.结果表明,随着热解温度的升高,生物炭的比表面积、总孔容、平均孔径增大,芳香性和稳定性也有所提高.羊粪生物炭吸附NOR的最佳初始pH为6.0,吸附在180 min左右达到平衡,采用准二级动力学模型能更好地拟合动力学数据(R~20.96),吸附速率由表面吸附和颗粒内扩散共同控制.等温吸附拟合发现,Langmuir模型能较好地描述NOR在羊粪生物炭上的吸附行为(R~20.93),吸附过程均为有利吸附,且可能与氢键和π-π键作用密切相关,4种热解温度下生物炭的吸附能力大小为:650℃550℃450℃350℃.吸附过程中ΔGθ0、ΔHθ0、ΔSθ0,表明羊粪生物炭对NOR的吸附是自发、吸热及熵增加的过程.650℃和550℃条件下制备的羊粪生物炭可作为水体中NOR的优势吸附材料. 相似文献
26.
George F. Antonious Eric T. Turley Regina R. Hill John C. Snyder 《Journal of environmental science and health. Part. B》2013,48(4):299-304
Organic matter and nutrients in municipal sewage sludge (SS) and chicken manure (CM) could be recycled and used for land farming to enhance fertility and physical properties of soils. Three soil management practices were used at Kentucky State University Research Farm, Franklin County, to study the impact of soil amendments on kale (Brassica oleracea cv. Winterbar) and collard (Brassica oleracea cv. Top Bunch) yields and quality. The three soil management practices were: (i) SS mixed with native soil at 15 t acre?1, (ii) CM mixed with native soil at 15 t acre?1, and (iii) no-mulch (NM) native soil for comparison purposes. At harvest, collard and kale green plants were graded according to USDA standards. Plants grown in CM and SS amended soil produced the greatest number of U.S. No. 1 grade of collard and kale greens compared to NM native soil. Across all treatments, concentrations of ascorbic acid and phenols were generally greater in kale than in collards. Overall, CM and SS enhanced total phenols and ascorbic acid contents of kale and collard compared to NM native soil. We investigated the chemical and physical properties of each of the three soil treatments that might explain variability among treatments and the impact of soil amendments on yield, phenols, and ascorbic acid contents of kale and collard green grown under this practice. 相似文献
27.
Pamela J. Edwards James N. Kochenderfer Donald W. Seegrist 《Journal of the American Water Resources Association》1991,27(2):265-274
ABSTRACT: Stream water chemistry was monitored on two watersheds on the Fernow Experimental Forest in north-central West Virginia to determine the effects of forest fertilization on annual nutrient exports. Ammonium nitrate and triple superphosphate were applied simultaneously at rates of 336 kg ha?1 N and 224 kg ha?1 P2O5, respectively, which are similar to rates used in commercial forest operations. The treatment significantly increased outputs of several ions. Annual outputs of nitrate N increased as much as 18 times over pretreatment levels, and calcium and magnesium increased as much as three times over pretreatment levels the first year after fertilization. Outputs for these nutrients were elevated for all three post-treatment years. Although nitrate N increased significantly, only about 20 percent of the applied fertilizer was accounted for in stream water exports. Outputs of phosphate P declined following fertilization, probably because the watersheds are phosphorus deficient, but by the third year, they slightly exceeded predicted values. Estimated nutrient losses to deep seepage were substantial, especially on the leakier south-facing catchmeat, on which some nutrient losses were equal to or greater than those in stream water. When the nutrient exports associated with both stream discharge and ground water recharge were combined, the percentages of applied N that were lost were similar on the two watersheds, averaging 27.5 percent. Less than 1 percent of the applied P was lost from either watershed in the combination of streamflow and deep seepage. 相似文献
28.
Some studies have been done dealing with cattle manure treatment, but literature scarcely reports the use of immobilized microalgae as final treatment of this waste. Recently, a complete technology for cattle manure treatment was established, including immobilized microalgae. The influence of the recirculation in the efficiency of the immobilized microalgae process was evaluated. 相似文献
29.
高温堆肥法处理污泥的探讨 总被引:2,自引:0,他引:2
对于污水处理后所产生的污泥,较好的方法是采用无害化、资源化农用技术,利用污泥为原料,制成有机复合肥,不仅解决了污水污泥的处理问题,还可推动环保产业的发展,促进农业生产,具有明显的经济、社会和环境效益。 相似文献
30.
Sustainable Agriculture: New Paradigms and Old Practices? Increased Production with Management of Organic Inputs in Senegal 总被引:2,自引:0,他引:2
Amadou Makhtar Diop 《Environment, Development and Sustainability》1999,1(3-4):285-296
Farmers in Sahelian countries are confronted with a variety of soil fertility and management problems. During the last two decades, NGOs have worked with farmers and research institutions to develop and test practices that will increase food production, while at the same time enhance the natural resource base.Since 1987, The Rodale Institute (RI) has worked closely with farmers' associations and government institutions to promote regenerative agriculture-farming systems that prioritize the use of local resources while improving them as they are used to grow food, using agro-ecological methods. The Senegalese Agricultural Research Institute has collaborated in this program as a partner of RI. The Senegal Regenerative Agriculture Resource Center model has been applied as a new and viable approach that builds on traditional knowledge and farmer-to-farmer exchange.Research results on soil conservation and improvement have shown that fields spread with amended animal manure or compost yield greater harvests than fields farmed with traditional methods. 相似文献