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971.
Long-term effects of farmyard manure and sewage sludge on some soil biochemical characteristics 总被引:2,自引:0,他引:2
A. Saviozzi A. Biasci R. Riffaldi R. Levi-Minzi 《Biology and Fertility of Soils》1999,30(1-2):100-106
Changes in some soil biochemical properties were investigated following repeated applications of aerobically digested sewage
sludge (SS) under field conditions over 12 years, and compared with those of an adjacent soil cultivated and amended with
5 t ha–1 year–1 (dry weight) farmyard manure (FYM) for at least 40 years, as well as with those of an adjacent uncultivated soil, in order
to ascertain changes in soil quality. A short-term aerobic incubation was used to determine the potential of the samples to
mineralize the organic C supplied. Results indicated that cultivation caused a reduction in total, humified and potentially
mineralizable organic C, total N, light-fraction (LF) C, total and water-soluble carbohydrates, phenolic compounds, cation-exchange
capacity (CEC), microbial biomass C, specific respiration, hydrolytic and urease activities, and an increase in the heavy
metal content. Total and water-soluble carbohydrates and phenolic compounds expressed as a percentage of total organic C (TOC)
were similar in the differently managed plots. Of the two amendments, FYM treatments showed higher amounts of TOC and N, LF-C,
total and water-soluble carbohydrates, phenolic substances, CEC, specific respiration of biomass, hydrolytic and urease activities,
similar amounts and characteristics of humified organic matter and lower concentrations of Cu, Zn and Cr. Both FYM and SS
were inadequate treatments for the restoration of soil organic matter lost as a consequence of cultivation.
Received: 20 October 1998 相似文献
972.
973.
广西有丰富的秸秆资源,发展千秆畜牧业的潜力巨大,千杆畜牧业是一项可持续发展的农业生产事业。秸杆的氨化技术可以有效地提高秸杆的营养价值,发展秸杆养畜,需要有优于牲畜品种,才能提高经济效益,所以,广西发展秸杆畜牧业,需要政府重视,政策跟进,大力推广秸杆氮化技术,加快引进热带型的优良黄牛品种改良广西黄牛品种的步伐。 相似文献
974.
Improvement and retardation of wound healing: effects of pharmacological agents in laboratory animal studies 总被引:1,自引:0,他引:1
Kietzmann 《Veterinary dermatology》1999,10(2):83-88
Impaired wound healing is an important problem; retardation of healing may be induced by endogenous and/or exogenous factors and treatments capable of ameliorating these effects are needed. The effects of solutions containing light ichthyol or povidone iodine, of ointments containing zinc oxide (ZO) and/or cod liver oil (CLO), and of a polyurethane-hydrogel foam wound dressing were examined on healing of full-thickness murine skin wounds impaired by systemic dexamethasone. The effects of the ointments were also studied on murine skin ulceration induced by subcutaneous sodium dodecyl sulphate solution. Light ichthyol at 1% and 2% but not at 5% and 10%, povidone iodine at 1% and the foam accelerated impaired healing. The ointments containing ZO or CLO accelerated healing of impaired full-thickness wounds and of ulcerated skin; ZO and CLO were synergistic. These studies demonstrate the value of murine models in the evaluation of agents employed in veterinary wound dressings. 相似文献
975.
猪肌肉组织中磺胺类药物的MSPD净化和HPLC测定 总被引:16,自引:1,他引:15
本文以基质固相分散(MSPD) 和高效液相色谱为基础,建立了猪肌肉组织中磺胺类药物多残留快速分析法。将05g 肌肉组织与适量C18 填料混合,研磨,制成半固态装柱,磺胺类药物经二氯甲烷洗脱后直接用反相高效液相色谱测定(UV270nm) 。在01 ~05mg/kg 添加浓度范围内7种磺胺类药物的平均回收率为706 % ±203 % 。检测限为001 ~01mg/kg。 相似文献
976.
对柔毛野豌豆进行了根瘤菌接种,使柔毛野豌豆的产草量提高了60%-69%,土壤多固氮30kg/hm^2,改良了土壤,增加了绿肥效果,为促进生态农业和生态畜牧业的有机结合开辟了新途径。 相似文献
977.
978.
为了减少舍外粪便污染,研究日粮中纳豆芽孢杆菌对体外猪粪发酵液中氨气、硫化氢、粪臭素及菌群的影响。试验组生猪饲喂纳豆芽孢杆菌日粮,对照组无纳豆芽孢杆菌。结果表明,试验组氨气、硫化氢、色氨酸、吲哚-3-乙酸、粪臭素浓度极显著低于对照组(P0.01),吲哚显著低于对照组(P0.05)。对照组猪粪发酵液优势菌以芽孢杆菌(CWBI B1434)为主,含量为26%;试验组以非解乳糖链球菌(AF201899)为主,含量为36%,其次为噬淀粉乳酸杆菌,含量为16%。结果表明纳豆芽孢杆菌通过调整猪粪菌群降低臭味物质浓度。为了减少舍外粪便污染,建议猪日粮中添加纳豆芽孢杆菌。 相似文献
979.
Adam D. Langworthy Ross Corkrey Richard P. Rawnsley Pieter J. M. Raedts James L. Hills 《Grass and Forage Science》2023,78(1):184-193
If the production of forage for dairy cattle is to become less reliant on synthetic nitrogen (N) fertilizers, there is need to better understand and account for the N contributed by on-farm and imported organic amendments. A 254-day aerobic soil incubation study (typical length of a growing season in many temperate dairying regions) quantified the inorganic (mineral) N supply from a commercial compost and dried bovine dung (i.e., on-farm effluent solids). Amendments were incubated in soils with contrasting synthetic N fertilization histories (i.e., 70–100 vs. 350–400 kg N/ha per year) to evaluate if higher synthetic N fertilization histories would reduce the lag time that often exists between organic amendment application and significant release of inorganic N for plant uptake. This proposition was based on previous research, which showed greater soil inorganic N availability accelerating organic amendment decomposition. Our experiment did find that the release of inorganic N from evaluated organic amendments was greater in soils with higher synthetic N fertilization histories, but that this effect was not apparent until after the first 6-months of this 9-month experiment. Despite this finding, soils with contrasting synthetic N fertilization histories were not found to differ in their initial inorganic N content, nor microbial activity or other physiochemical properties known to affect N mineralization. Our study highlighted the long-term vision needed when transitioning from synthetic N fertilizers to organic amendments, with most of the N present in the compost and dried dung remaining unavailable for forage production (i.e., remained bound in organic carbon-based molecules). 相似文献
980.
选取9个春油菜绿肥品种进行田间试验,连续翻压两年后,测定土壤和玉米子粒中的微量元素含量,研究比较不同春油菜绿肥品种翻压对土壤微量元素含量及玉米吸收情况的影响。结果表明,中油肥1804翻压后土壤全量铁、锰和锌含量较春闲田CK处理分别提高了9.31%、5.71%、9.97%,土壤有效态铁、锰、锌含量较春闲田CK处理分别提高37.31%、62.35%、73.99%;中油肥1907翻压后土壤全铜含量较春闲田CK处理显著提高了84.29%;中油肥1901翻压后较春闲田CK处理显著提高了玉米子粒铁、锰、锌的吸收量及玉米产量和品质。不同春油菜绿肥品种翻压后土壤有效态铜含量、玉米子粒铜及锰含量与春闲田CK处理之间差异不显著;土壤有效态微量元素含量与春油菜中微量元素和土壤全量微量元素含量之间存在线性关系,且微量元素与玉米叶片叶绿素、含氮量、产量、可溶性糖、蛋白质呈显著或极显著正相关。华北地区种植并翻压中油肥1804、中油肥1901、中油肥1907能较好地提高土壤微量元素含量、生物有效性及玉米产量和品质。 相似文献