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1.
2.
Caroline C. MBA 《Environmental management》1994,18(2):257-261
Four microbial isolates, OP2, OP3, OP6, and OP7, of earthworm casts ofPontoscolex corethrurus were found to be acid tolerant actinomycetes and efficient rock phosphate (RP) solubilizers that could grow fast on NH4Cl-enriched or N-free carboxymethyl cellulose or glucose as sole carbon source.
CMC (carboxymethyl cellulose) induced production of extracellular cellulase enzyme and the production of reducing sugar in
all the isolates. RP solubilizing power was observed to be inversely related to glucose consumption. The most efficient RP
solubilizer was found to consume the least glucose.
Growth was faster on cellulose than on glucose media. N-free CMC induced greater glucose production than NH4Cl-enriched CMC medium. Both CMC and glucose media were acidified by all the isolates, however, RP solubilizing power decreased
with acidification. Solubilization power was greatest with isolate OP7, which also produced the greatest amount of reducing
sugar per gram CMC. Both RP solubilizing power and the cellulolytic efficiency varied among isolates. A minimum of 631 μg
P/0.1 g RP and a maximum of 951.4 μg P/0.1 g RP was recorded. 相似文献
3.
潮土细菌及真菌群落对化肥减量配施有机肥和秸秆的响应 总被引:6,自引:0,他引:6
为了研究化肥减量配施有机肥和秸秆对华北麦玉轮作田潮土细菌和真菌群落的影响,在天津市宁河区试验基地开展田间定位施肥试验,采用Illumina高通量测序技术比较了5种施肥模式(单施化肥处理,F;化肥减施处理,FR;化肥减量与秸秆配施处理,FRS;化肥减量与有机肥配施处理,FRO;化肥减量与有机肥和秸秆配施处理,FROS)下土壤细菌及真菌群落的组成、多样性和结构差异,并结合土壤理化性质分析,探究不同施肥处理下驱动细菌和真菌群落变化的关键土壤环境因子.结果表明,FRO处理显著提高了土壤SOM含量.FROS处理的TP含量显著高于FRS处理,增加了13.33%.FRO和FROS处理AP含量较其它处理显著增加,NH4+-N含量显著高于化肥处理(F和FR).各施肥处理土壤中优势细菌门类均为变形菌门(Proteobacteria)、放线菌门(Actinobacteria)、绿弯菌门(Chloroflexi)和酸杆菌门(Acidobacteria),优势真菌门类均为子囊菌门(Ascomycota).在化肥减量配施有机肥(FRO)的基础上添加秸秆(FROS)显著降低了放线菌门(Actinobacteria)的相对丰度.FRS和FROS处理均显著降低了芽单胞菌门(Gemmatimonadetes)的相对丰度.FROS处理显著提高了浮霉菌门(Planctomycetes)和疣微菌门(Verrucomicrobia)的相对丰度.对于真菌群落而言,有机肥(FRO和FROS)的施入显著提高了子囊菌门(Ascomycota)的相对丰度.与FR处理相比,FROS处理显著降低了被孢菌门(Mortierellomycota)和油壶菌门(Olpidiomycota)的相对丰度,且FRS处理同样显著降低了油壶菌门(Olpidiomycota)的相对丰度.FROS处理的细菌群落Shannon多样性指数显著高于F和FR处理,分别增加了1.26%和1.25%,Chao1指数较F处理显著增加了4.51%,细菌Shannon多样性指数与AP和NH4+-N含量显著正相关(P<0.05).与FR处理相比,FRS、FRO和FROS处理显著降低了真菌群落Shannon多样性指数,分别达到29.85%、24.94%和25.73%,真菌Shannon多样性指数与AP含量显著负相关(P<0.05).细菌群落结构在FROS处理下显著区别于F、FR和FRO处理,土壤SM、TP、pH和AP是导致细菌群落结构变化的主要驱动因子;真菌群落结构在FRO和FROS处理下显著区别于F和FR处理,真菌群落结构变化主要受土壤TN、AP和TP的驱动.综上所述,添加有机肥和秸秆改变了土壤理化性质,进而改变了土壤细菌和真菌群落组成,土壤真菌对有机物料的敏感程度高于细菌,细菌和真菌群落结构均受到土壤P的调控,在潮土农业耕作中应引起充分重视. 相似文献
4.
Qiuyi Ji Huan He Zhanqi Gao Xiaohan Wang Shaogui Yang Cheng Sun Shiyin Li Yong Wang Limin Zhang 《环境科学学报(英文版)》2020,32(12):55-61
Tri(2-chloroethyl) phosphate (TCEP) with the initial concentration of 5 mg/L was degraded by UV/H2O2 oxidation process. The removal rate of TCEP in the UV/H2O2 system was 89.1% with the production of Cl? and PO43? of 0.23 and 0.64 mg/L. The removal rate of total organic carbon of the reaction was 48.8% and the pH reached 3.3 after the reaction. The oxidative degradation process of TCEP in the UV/H2O2 system obeyed the first order kinetic reaction with the apparent rate constant of 0.0025 min?1 (R2=0.9788). The intermediate products were isolated and identified by gas chromatography-mass spectrometer. The addition reaction of HO? and H2O and the oxidation reaction with H2O2 were found during the degradation pathway of 5 mg/L TCEP in the UV/H2O2 system. For the first time, environment risk was estimated via the “ecological structure activity relationships” program and acute and chronic toxicity changes of intermediate products were pointed out. The luminescence inhibition rate of photobacterium was used to evaluate the acute toxicity of intermediate products. The results showed that the toxicity of the intermediate products increased with the increase of reaction time, which may be due to the production of chlorine compounds. Some measures should be introduced to the UV/H2O2 system to remove the highly toxic Cl-containing compounds, such as a nanofiltration or reverse osmosis unit. 相似文献
5.
为了阐明餐厨垃圾生物有机肥改良贫瘠土壤的作用机制,以贫瘠黄褐土为研究对象,通过不施肥、长期(>5 a)施用化肥、中长期(5 a)施用少量餐厨垃圾生物有机肥和短期(1 a)施用大量餐厨垃圾生物有机肥4种施肥方式,分别记为CK组、CF组、LOF-5组和MOF-1组,对比分析不同施肥方式对土壤OM(有机质)、活性有机碳、营养元素和团聚体等的影响.结果表明:①施用餐厨垃圾生物有机肥可显著提高土壤OM、活性有机碳含量,其中,MOF-1组提高效果最显著,与CK组相比,w(OM)可提高173.29%,w(ROC)(ROC为易氧化有机碳)增加了39.17%,w(POC)(POC为颗粒有机碳)和w(DOC)(DOC为可溶性有机碳)分别是CK组的13.85和10.32倍.②中长期(5 a)施用少量餐厨垃圾生物有机肥可增加土壤中较大粒径团聚体的占比,且更有利于提高土壤团粒结构的稳定性,LOF-5组>2 mm粒级的团聚体占比是CK组的4.68倍;与CK组相比,LOF-5组MWD(平均重量直径)增加了100.00%,GMD(几何平均直径)增加了82.98%,>0.25 mm水稳定性团聚体质量占比(DR0.25)增加了27.20%.③中长期(5 a)施用少量餐厨垃圾生物有机肥可增加土壤中w(TN)(TN为全氮)和w(AN)(AN为速效氮),与CK组相比,LOF-5组w(TN)和w(AN)分别增加了77.42%和20.82%.施用餐厨垃圾有机肥也可同时增加土壤中w(AP)(AP为速效磷)和w(AK)(AK为速效钾),MOF-1组增加效果较佳,w(AP)和w(AK)分别是CK组的9.43和3.39倍.研究显示,中长期(5 a)施用少量餐厨垃圾生物有机肥可提升土壤固碳能力,提高土壤养分利用的有效性,从而提升耕地土壤质量,减少化肥施用量,是我国贫瘠黄褐土改良的有效施肥模式. 相似文献
6.
选取湖南省浏阳市某Cd污染稻田进行田间试验,研究组配改良剂石灰石+海泡石(LS)、基施硅肥及叶面喷施硅肥对Cd污染稻田修复效果,结果表明:(1)基施硅肥90kg/hm2和叶面喷施硅肥(0.2,0.4g/L)对土壤pH值无明显影响,添加LS(2250,4500kg/hm2)的各处理均显著提高土壤pH值(P < 0.05).(2)基施硅肥90kg/hm2分别降低土壤交换态、毒性特征浸出(TCLP)提取态Cd含量20.0%和18.5%,叶面喷施硅肥对土壤Cd两种提取态含量无明显影响,添加LS的各处理(2250,4500kg/hm2)分别使土壤交换态、TCLP提取态Cd含量降低25.8%~49.9%、26.4%~44.5%.(3)3种单一技术措施均能明显降低水稻各部位Cd含量,但降低糙米中Cd含量的效果低于3种技术措施的组合处理;“组配改良剂LS+基施硅肥+叶面喷施硅肥”各处理(JL1F1、JL1F2、JL2F1、JL2F2)使水稻糙米中Cd含量降低25.6%~70.5%.(4)“组配改良剂LS+基施硅肥+叶面喷施硅肥”的组合技术处理能显著降低土壤中Cd的有效性,显著降低水稻各部位中Cd含量,其中JL2F2处理效果最佳,能使对照糙米Cd含量从0.66mg/kg降低到0.19mg/kg,实现中重度Cd污染稻田的水稻安全生产. 相似文献
7.
氨基酸法现场快速测定废水中的磷酸盐 总被引:3,自引:0,他引:3
通过磷酸盐与钼酸盐、氨基酸反应使样品呈淡蓝色,讨论了在事故现场快速测定水中磷的方法。试验表明方法灵敏,操作简单快速。检测范围0~15mg/L。 相似文献
8.
以成年产卵来航母鸡为试验动物,研究了三甲基苯基磷酸酯(Tri-o-CresylPhos-phate,TOCP)诱导的迟发性神经毒性.试验发现,母鸡口服TOCP(750mg/kg)后,经过大约8-10d的潜伏期开始出现中毒症状,其表现为以步态失调为主要特征的运动障碍呈进行性加重,至第21d开始便发展为瘫痪,对鸡脑神经病损靶标酯酶(NeuropathyTargetEnzyme,NTE)活性的测定表明,有机械诱导的迟发性神经毒性(Organophosphate-InducedDelayedPolyneuropathy,OPIDP)与NTE活性抑制之间的关系不平行,其毒性症状的轻重与NTE活性被抑制的强弱也不呈正相关,很可能,在给药后24h,体内OPIDP已被触发,此外,实验观察到给予TOCP后被试鸡的体重明显下降。 相似文献
9.
Controlled-release fertilizer(CRF):A green fertilizer for controlling non-point contamination in agriculture 总被引:9,自引:0,他引:9
Fertilizers contribute greatly to high yields but also result in environmental non-point contamination, including the emission of greenhouse gas(N2O) and eutrophication of water bodies. How to solve this problem has become a serious challenge, especially for China as its high ecological pressure. Controlled-release fertilizer(CRF) has been developed to minimize the contamination while keeping high yield and has become a green fertilizer for agriculture. Several CRFs made with special coating technology were used for testing the fertilizer effects in yield and environment through pot experiment and field trial. The result indicated that the CRFs had higher N use efficiency, thus reducing N loss through leaching and volatilization while keeping higher yields. Comparing with imported standard CRFs,the test on CRFs showed similar fertilizer effect but with much lower cost. CRFs application is becoming a new approach for minimizing non-point contamination in agriculture. 相似文献
10.
WU Shao-fu WU Liang-huan SHI Qi-wei WANG Zhong-qiang CHEN Xian-you LI Yong-shan 《环境科学学报(英文版)》2007,19(7)
In this study, soil column was used to study the new nitrification inhibitor 3,4-dimethylpyrazole phosphate (DMPP) on nitrate (NO3--N) and potassium (K) leaching in the sandy loam soil and clay loam soil. The results showed that DMPP with ammonium sulphate nitrate (ASN) ((NH4)2SO4 and NH4NO3) or urea could reduce NO3--N leaching significantly, whereas ammonium (NH4 -N) leaching increased slightly. In case of total N (NO3--N NH4 -N), losses by leaching during the experimental period (40 d) were 37.93 mg (urea), 31.61 mg (urea DMPP), 108.10 mg (ASN), 60.70 mg (ASN DMPP) in the sandy loam soil, and 30.54 mg (urea), 21.05 mg (urea DMPP), 37.86 mg (ASN), 31. 09 mg (ASN DMPP) in the clay loam soil, respectively. DMPP-amended soil led to the maintenance of relatively high levels of NH4 -N and low levels of NO3--N in soil, and nitrification was slower. DMPP supplementation also resulted in potassium leached less, but the difference was not significant except the treatment ASN and ASN DMPP in the sandy loam soil. Above results indicate that DMPP is a good nitrification inhibitor, the efficiency of DMPP seems better in the sandy loam soil than in the clay loam soil and lasts longer. 相似文献