Effect of long-term application of corn stalks and inorganic fertilizers on fluorescence characteristics of water extractable organic matter in a meadow black soil of northeast China

ABSTRACT

Returning crop residues into fields, either alone or in combination with inorganic fertilizer, is considered as a practical way to enhance soil fertility. However, information concerning the effects of crop residues and inorganic fertilizer application on water extractable organic matter (WEOM) in soil is scarce. The aim of this study was to examine the 10-year effect of corn residue (CR) return with or without the application of nitrogen, phosphorus, and potassium (NPK) fertilizer on the quantity and quality of WEOM in a black soil of northeast China by means of ultraviolet absorbance, fluorescence excitation--emission matrix, and derived spectroscopic indices. The application of NPK fertilizers and CR, alone or together, increased the content of total soil organic carbon (SOC), water extractable organic carbon (WEOC), and ratio of WEOC/SOC, with the sequence being NPK + CR > CR > NPK > CK. Compared with control treatment, the individual application of NPK fertilizer decreased the aromaticity of WEOM. In contrast, elevated proportion of tryptophan-like fluorophore and microbially derived fulvic acid-like components with low molecular weight was detected in the WEOM. The amendment with CR alone resulted in increase in aromaticity of WEOM and proportion of plant-derived humic acid-like component with large molecular weight, accompanied by reduced proportion of tyrosine-like compounds. For the soil with CR restoration, the application of NPK fertilizer increased aromaticity of WEOM, and large molecular weight fulvic acid-like and humic acid-like compounds were found. However, the proportions of tyrosine-like and tryptophan-like compounds were diminished. The quantitative and qualitative analysis of WEOM using fluorescence spectroscopy describes responses to be observed in long-term different fertilization strategies.     

餐厨垃圾废水制备液态解磷菌剂研究

本研究探讨了餐厨垃圾废水用作发酵基质生产液态解磷巨大芽孢杆菌菌肥的可行性.结果表明,餐厨垃圾废水培养的巨大芽孢杆菌经过3~4d的调整期即进入对数生长期,第6~7d活菌数达到最大,而经过湿热预处理得到的II类废水较I类废水更适宜用作巨大芽孢杆菌的培养基质,其菌液活菌数是I类废水培养的活菌数的5倍（4.8×10¹⁵CFU/mL）.废水中的盐分对巨大芽孢杆菌的生长代谢影响显著：活菌数随着NaCl含量的增加先升高后快速降低,最利于菌种培养的NaCl浓度为10g/L.pH值和温度极显著影响巨大芽孢杆菌的生长,而摇床转速和接种量对菌株培养影响不显著,正交试验确定的较优培养条件为pH=8、T=35℃、转速80r/min、接种量2%（V/V）.餐厨垃圾废水制备的解磷菌肥可实现土壤中固化磷的有效磷化：施用0.025‰~2.5‰质量比例解磷菌剂的土壤生长的黄豆苗干重可达到按照5‰质量比例施加无机复合肥生长的黄豆苗的70.7%~84.5%,其中微生物菌肥的最佳施用量为0.25‰.     

长期施肥对水稻土酶活性及理化特性的影响

为了明确不同施肥种类对水稻土土壤肥力与酶活性的影响,以30年（1981年至今）长期定位试验地为基础,研究不同施肥处理（CK,N,P,K,NPK,2倍NPK,NPK＋猪粪）水稻田耕层（0-20cm）土壤酶活性与养分的变化趋势及其相关性。结果表明：1）施P（配施或单施）增加土壤全P、速效P含量,平衡施肥配施有机肥（NPK＋猪粪处理）土壤的有机质、全P、速效P、全N、速效N均显著增加,所有施肥处理间pH值差异均不显著;2）除了NPK处理土壤脲酶活性最高外,平衡施肥配施有机肥土壤转化酶、酸性磷酸酶、过氧化氢酶活性均较其他处理显著增加;3）酸性磷酸酶活性与土壤全P量呈负相关,过氧化氢酶、脲酶、转化酶与全N、有机质、速效N、速效P呈显著或极显著正相关;因此,水田土壤长期平衡施肥配施有机肥,能显著提高土壤肥力,增加土壤酶活性,有益于土壤生产力的持续提高。     

氮肥、磷肥、粉煤灰和CaCO3对As(Ⅲ)胁迫下小麦幼苗生物效应及成熟期籽粒As含量的影响

采用盆栽的方法,研究了在As污染土壤中施加氮肥、磷肥、粉煤灰和CaCO₃对小麦籽粒萌发、幼苗生理及成熟期籽粒w(As)的影响,并探讨了4种改良剂对在As污染土壤上种植小麦的有效改良方法. 结果表明:适量的氮肥、磷肥、粉煤灰和CaCO₃对As污染土壤的小麦萌发和幼苗生长具有明显的促进作用,能有效缓解As对小麦的毒害,并降低成熟期籽粒的w(As). 表现为出苗率、幼苗株高、植株鲜重增大,w(叶绿素a)升高,丙二醛(MDA)含量和w(游离脯氨酸)下降,成熟期籽粒的w(As)降低.      

Fluoride distribution in the environment along the gradient of a phosphate-fertilizer production emission (southern Brazil)

Airborne fluoride was determined in the rainwater, surface soil and groundwater along a gradient of emission of a phosphate fertilizer factory in Rio Grande, southern Brazil. Concentrations of fluoride in rainwater and groundwater achieved 3 mg l⁻¹ and 5 mg l⁻¹, respectively, and were dependent on pH. The fluoride deposited from emissions accumulated in a superficial horizon of soil in quantities comparable to those in the manufactured end-products—up to 23,000 mg kg⁻¹. Fluoride distribution in the environment is controlled by physical–chemical parameters of emission, rain intensity and soil properties. The highest fluoride concentrations were registered at a close distance of up to 2 km from the factory. The distribution of fluoride in groundwater resembled the same distribution in rainwater due to the high permeability of the local soils. Fluoride penetration to the groundwater also depended on the type of vegetation cover. The groundwater in woodland areas was less affected by contamination of fluoride than in the grassland areas, most probably because of the influence of eucalyptus throughfall, which increases the pH of wet precipitates.     

生活垃圾转化高效生物有机肥料的肥效研究

利用城市生活垃圾制备高效生物有机肥料,分别应用于小麦、黄瓜、玉米等作物,并观察施肥后对农作物及土壤理化性质的影响,结果表 明生活垃圾转化成高效有机肥料对作物生长有明显的促进作用,可增强作物抗病能力,增加农作物产量,还可以提高土壤肥力,改善土壤结构。      

农药和化肥对无尾两栖类蝌蚪的毒性效应研究进展

以两栖动物研究环境污染物的毒性效应进而监测环境的变化,已成为国内外的研究热点.两栖类的胚胎发育和变态过程对水的依赖性极强,而且鳃和皮肤有很强的渗透性,当其受到污染胁迫时,在细胞、组织及生理生化水平上都会发生显著变化,进而会影响其存活和生长发育.在总结国内外相关研究基础上,综述和分析了农药、化肥(氮肥)对无尾两栖类蝌蚪的行为表现、生长发育、组织结构和生理生化变化等方面的毒性效应,以期为农药、化肥的水环境监测及合理使用提供全面的科学依据.     

粉煤灰微生态复混肥的制备与研究

研究了利用处理啤酒废水的粉煤灰废渣作为固氮菌的载体,与常规的氮肥、钾肥和磷肥复混生产粉煤灰微生态复混肥的依据、原理与工艺.粉煤灰微生态复混肥总养分31%,其中养分比例为N∶P2O5∶K2O∶有机物=1∶2.01∶0.96∶0.79,固氮菌数6.9×107个/g,粉煤灰占质量分数44.03%.通过小白菜等作物的种植试验表明,粉煤灰微生态复混肥具有改良土壤结构,长效缓释,均衡作物营养,增强作物抗逆性和抗病能力,改善作物品质等优点,对作物植株性状的生长优势明显优于常规施肥法.     

Determination of Nitrogen and Sulfur in Plants and Soils Sampled from the Area Near a Fertilizer Plant

The purpose of this study was to investigate NO_x and SO₂-inducednitrogen and sulfur levels accumulated over vegetation and soil in the surrounds of the fertilizer plant in Kütahya, Turkey. Therefore, leaf samples collected from the seven locations adjacent to the plant were morphologically observed (pollution-related injuries and color deformation) and chemically analyzed. Besides, nitrogen and sulfur contents were determined in the soil samples collected from each location. A significant correlation was achieved between locations and different vegetation samples and soil samples. The highest nitrogen level present in the trees was 3.07 ± 0.105% (3rd location, Robinia pseudoacacia), with the highest sulfur level being 5.79 ± 0.085% (3rd location, Salix alba). The highest nitrogen and sulfur levels in soils were 0.31 ± 0.045 and 0.57 ± 0.052% (3rd location), respectively. Furthermore, the highest nitrogen and sulfur levels were 4.69 and 2.20%, respectively,in agricultural plants in the surrounds of the fertilizer plant. A higher level of pollutants was observed in the samples collectedfrom the locations in the direction of the prevailing wind. Also, differences between locations as well as between plant specimens were statistically evaluated.     

保氮增效剂调节氮肥施用量和利用率的研究 Ⅱ.保氮增效剂在小麦生产中的应用效果

利用田间试验研究了氮肥与保氮增效剂共施的效应函数和保氮增效剂促进小麦省肥增产的比较效果。同的供氮水平,保氮增效剂均能改善小麦植株经济性状,促进籽粒增产,提高氮肥报酬和施肥利润。保氮增效剂用量为氮肥实物量的5%作小麦基肥,旱地增产45～52.5kg/亩,稻田增产54.5～74.5kg/亩,氮肥报酬提高41.4～68.6%。