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1.
This study characterized poultry manure extract (tea) and investigated the effects of integrated use of tea and the sequence of phosphorus (P) application [P added before (PBT), after (TBP), or jointly (PT) with tea] on P-sorption characteristics on acidic, alkaline, and neutral tropical soils. Results indicated that diluted tea contained 400 mg nitrogen, 155.80 mg potassium, and 10.48 mg P L?1 and the nutrients were greatest after 2 weeks. Soil P sorption conformed to the Freundlich model, indicating that soil P affinity was less than the aqueous solution at low solution P concentration. Freundlich index (k) in neutral soil was 78 and 94% greater than in acidic and alkaline soils, respectively. The lowest P sorption efficiency and greatest phosphate requirement were in acidic soil. Poultry manure tea could enhance P availability and reduce P fixation irrespective of the sequence of application of tea and P.  相似文献   

2.
Abstract

Because manure organic phosphorus (P) is environmentally bioactive, a novel in situ enzyme hydrolysis assay was developed to identify water soluble‐ and labile complexed P and mechanisms controlling P solubilization in dairy manure. Water‐extractable P averaged 16% (±14.8%) of total P of 107 manures collected across five northeastern states of the USA. Adding a multidentate ligand solubilized inorganic complexed P (15±8.3%) primarily associated with calcium (Ca) and magnesium (Mg). An additional organic fraction (35.9±15.6%) was hydrolyzable by fungal phytases. The assay was more revealing about on‐farm P management than just knowing total P; the water‐extractable P distribution was skewed to the left, and two thirds were <2500 mg kg?1; bioactive and total P were normally distributed, differing extensively between farms with a range spanning an order of magnitude. The assay's simplicity and robustness over the wide range of manure characteristics may increase routine evaluation of whole‐farm accumulation of environmentally sensitive P forms.  相似文献   

3.
Abstract

Laboratory drying may alter manure phosphorus (P) distribution. The effects of freeze, air (22°C), and oven (65°C) drying on sequentially fractioned poultry manure P were examined. Higher drying temperatures resulted in lower percentage of dry matter. Increased H2O‐ and decreased sodium bicarbonate (NaHCO3)‐extractable P with drying provided evidence that drying increases poultry manure P solubility. Labile fractions were predominantly inorganic P (Pi), whereas sodium hydroxide (NaOH) and hydrochloric acid (HCl) fractions had significant amounts of organic P (Po). Drying altered H2O‐ and NaHCO3‐extractable Pi but had no consistent effect on Po in these fractions. This work suggests that variations due to drying should be taken into consideration when evaluating manures for P availability or when comparing data in which different drying methods have been utilized.  相似文献   

4.
Using solution 31P NMR spectroscopy, we compared three extractants, deionized water, sodium acetate buffer (pH 5.0) with fresh sodium dithionite (NaAc-SD), and 0.25 M NaOH–0.05 M ethylenediaminetetraacetic acid (NaOH-EDTA), for the profile of P compounds in two dairy fecal samples. Phosphorus extracted was 35 percent for water and 80–100 percent for NaAc-SD and NaOH-EDTA. Water extracted a greater proportion of organic P forms, particularly orthophosphate diesters, but a lower proportion of orthophosphate relative to NaOH-EDTA and NaAc-SD. Phosphorus recoveries and spectra were generally similar for NaOH-EDTA and NaAc-SD, but there was increased degradation of polyphosphate to pyrophosphate with NaOH-EDTA, and water, for one sample relative to NaAc-SD. For studies characterizing and quantifying all the P forms in manure and fecal samples, these results suggest that either NaOH-EDTA or NaAc-SD would be a good choice. However, extraction with water may be a better choice for studies monitoring labile manure P and potential environmental impact.  相似文献   

5.
湿地沉积物磷的吸附与解吸研究   总被引:1,自引:0,他引:1  
采用恒温培养法研究美国纽约Pelham Bay Park 6种典型淡水湿地沉积物中磷的吸附与解吸行为及其动力学过程。结果表明:湿地沉积物具有强烈吸附溶液中磷的功能,随着溶液中磷浓度的增加,吸附量增大;但是湿地沉积物也有释放磷到溶液中去的功能,释放量为0~41.19 mg/kg,与沉积物吸附磷量的关系不大,沉积物释放磷与沉积物的特性有关。衡量一种淡水湿地沉积物的除磷能力,可根据沉积物最大吸附磷量和吸附解吸附平衡浓度(EPC0)来衡量,6种沉积物中,磷的最大吸附能力强弱依次是:S1>S2>S3>S6>S5>S4;S1沉积物吸附磷的最大量为500 mg/kg。各沉积物的平衡浓度相差很大,S4的吸附与解吸附平衡浓度最高,其值为166.00μg/L,而S2的吸附与解吸附平衡浓度最低,其值为0.36μg/L。低的EPC0值表明,沉积物有很强的吸附磷的能力,故S2湿地生态系统有非常强的除磷能力。  相似文献   

6.
A column leaching experiment using three soils (Inceptisol, Ultisol, and Andisol) and seven livestock manure composts that had different characteristics was conducted for 19 weeks to investigate the interactive effects of composts and soils on the phosphorus (P) leaching potential of compost-amended soils and to identify the principal variables that affect P leaching. Cumulative total P leaching (TPcum) tended to increase with increasing total and available P concentration in the soils. Among various compost properties, total P concentration was positively correlated with TPcum from the compost-amended soils, except for the Andisol, which has a high P-sorption capacity. There was no significant relationship between TPcum and water-extractable P concentration of the composts, suggesting that total P rather than inorganic P concentration of composts may be successfully used in predicting P leaching potential from compost-amended soils except for soils that have a high P-sorption capacity, as in Andisol.  相似文献   

7.
随着畜禽粪便农田施用量的增加,畜禽粪便中磷流失也越来越引起人们的重视。采用取样分析和室内土柱模拟的方法,研究了猪粪和鸡粪中磷在水、0.5mol·L^-1NaHCO3和土体中的释放运移特点。结果表明,猪粪经H2O和NaHCO3连续提取后,H2O提取液中无机磷(P)i占猪粪全磷(TP)的21.58%,NaHCO3提取液中Pi占猪粪TP的28.92%;鸡粪经H2O和NaHCO3连续提取后,H2O提取液中Pi占鸡粪TP的18.09%,NaHCO3提取液中Pi占鸡粪TP的17.88%;施用猪粪和鸡粪处理土柱淋溶液中水溶性总磷(TDP)、水溶性无机磷(DRP)和水溶性有机磷(DOP)浓度均随着淋溶次数的增加呈先上升后降低的趋势,施用猪粪处理磷释放速率比施用鸡粪处理快;大量施用猪粪和鸡粪后,0~30cm土体中土壤全磷(TP)和0~60cm土体中土壤速效磷(Olsen-P)的含量显著增加。  相似文献   

8.
周驰  宋春雷  陈玺  李阳  曹秀云  周易勇 《土壤》2013,45(1):60-66
以巢湖沿岸土壤和沉积物为对象,分析了速效磷、藻类可利用性磷、有机磷含量和碱性磷酸酶活性的空间变化格局,并测定了磷吸附参数.结果表明,土壤有机磷含量差异显著,以草地最高,而速效磷和藻类可利用性磷含量无明显差异;酶活性及速效磷含量与有机磷含量呈显著正相关,土壤对正磷酸根的吸附量与土壤中有机磷含量呈正相关;湖泊沉积物中有机磷含量与周边土壤中有机磷含量显著正相关.因此,土壤有机磷及其酶促水解过程是调节沉积物作为磷源或磷汇功能的关键因素之一.  相似文献   

9.
利用沉积物磷吸附指数(PSI)和磷吸附饱和度(DPS)研究了东平湖表层沉积物的磷吸附容量,并讨论了沉积物中磷的潜在释放风险。结果表明,表层沉积物的磷吸附指数变化范围为30.3~45.2[mg P·(100g)-1]·(μmol·L-1)-1,表现出从湖心、湖东向湖北、湖南逐渐增大的扇形特征;而磷吸附饱和度变化范围为6.5%~24.1%,与磷吸附指数变化趋势恰好相反。磷吸附指数与沉积物中草酸铵提取的铁(FeOX)含量呈极显著正相关,与草酸铵提取的铁铝总量呈显著正相关,磷吸附饱和度与沉积物中草酸铵提取的磷(POX)含量呈显著正相关。此外,磷释放风险指数(ERI)变化范围为14.9%~67.5%,表明东平湖表层沉积物中磷释放诱发富营养化的风险处于高度风险范围。  相似文献   

10.
Increase in phosphorus (P) availability with fertilizer addition is influenced by soil properties such as P sorption capacity. We investigated P availability changes and response of maize (Zea mays L) to four P fertilizers rates (0, 20, 30 and 40 kg ha?1) in a two-site field experiment, having soils of contrastingly different available P (2.9 and 22.1 mg kg?1) and P sorption capacities (171.9 and 54.2 mg kg?1). Increase in available P was significantly greater in the soil with higher available P but lower P sorption capacity, than in the other; however, yield responses were similar in the two soils. Fertilizer P rates of 30 and 40 kg ha?1 gave significantly greater maize yields than the unfertilized treatment in both soils. Results suggest the need to account for the P sorption capacity when deciding rates of P fertilizers to increase available P in soils.  相似文献   

11.
Abstract

Investigating the relation between concentration or release of phosphorus (P) into soil solution (CaCl2‐P, determined by 0.01 M CaCl2 extraction of soils) and soil test phosphorus (Olsen P, or 0.5 N NaHCO3‐extractable soil phosphorus) for 10 widely ranging and variously managed soils from central Italy, a change point was evident where the slopes of two linear relationships meet. In other words, it was possible to distinguish two sections of the plots of CaCl2‐P against Olsen P, for which increases of CaCl2‐P per unit of soil test P increase were significantly (p<0.05) greater above than below these change points. Values of change point ranged from 14.8 to 253.1 mg kg?1 Olsen P and were very closely correlated (p<0.001) to phosphorus sorption capacity of soils. Similar change points were also previously observed when Olsen P (and also Mehlich 3 P) of surface soils was related to the P concentration of surface runoff and subsurface drainage. Because insufficient data are available relating P in surface soils and amount of P loss by overland, subsurface, or drainage flow, using the CaCl2 extraction of soil can be convenient to determine a change point in soil test P, which may be used in support of agricultural and environmental P management.  相似文献   

12.
Plant-based phosphorus (P) remediation strategies have been suggested to reduce high P accumulation in soil. Eleven fodder soybean genotypes were evaluated to explore their potential for the removal of P from poultry manure-enriched soils. Field experiments were conducted at a site that had a history of heavy poultry manure applications. Green house experiments were conducted using the soils selected for field trials to confirm the results. Harvesting of whole plants, excluding roots of the genotypes, was done at the pod formation stages and plant samples were oven dried at 70°C for three days. The dry samples were ground and analyzed for total P content. Genotype 091734, provided the maximum P removal from amended and unamended soils. Fodder soybean genotypes could play an important role in the extraction of P from poultry manure-enriched soils, which are important from the ecological point of view.  相似文献   

13.
采用平衡吸附法研究了风沙土不同有机组分对磷的吸附特征影响,可为有机组分吸附态磷携载量估算提供依据。结果表明:去除有机质后的风沙土对磷的吸附能力大大降低,其碳标化饱和吸附量(Гmo)c和吸附分配系数(ko)c分别只能达到重组的27.76%和8.45%,说明有机质是影响磷在风沙土上吸附特征的重要因素;磷在轻组有机组分上的吸附以分配作用为主(koc=51.02);风沙土有机组分中的重组有机质对磷的吸附起主导作用(Гmoc=388.35mg.kg-1),重组有机组分中的紧结态腐殖质(胡敏素)对磷的吸附起关键作用(Гmoc=1007.96mg.kg-1),影响机制主要为稳、紧结态腐殖质是形成土壤疏松多孔团聚体结构的重要胶结物质。在其所形成的有机矿质复合体中除分配作用吸附外,还存在着孔隙填充方式的磷吸附;考查土壤对磷的吸附能力不但要考虑有机质的含量,更要考虑有机质的存在形态,它也是影响土壤对磷吸附特征的重要因素。以重组为基准,轻组有机组分以及重组有机组分中稳结态腐殖质和紧结态腐殖质携载的吸附态磷分别可按0.69倍以及1.37、2.75倍估算。  相似文献   

14.
Knowledge of the amount of nutrients in soil is required to achieve sustainable management. The objective of this study was to assess the variability of soil‐available and single‐point buffering index of phosphorus (P) in the farmlands of the Khoy region, Iran. Composite soil samples (0–30 cm) were collected at 114 locations on regular grid of 1000 m. Some soil physico‐chemical characteristics such as soil texture, soil organic matter (OM) content, soil pH, electrical conductivity (EC), calcium carbonate equivalent (CCE), available P (Pava) and single‐point P sorption index (PSI) were measured. Results showed that all variables in this study have spatial distribution in the effective range of 1500–4800 m. Moreover, experimental semivariograms of all studied variables were best‐fit by spherical and exponential models. Most importantly, kriged maps revealed that a major part of the study area contains high Pava, which is seemingly due to the frequent application of phosphate fertilizers along with poultry manure. Some soils in the western part showed low PSI index; they therefore need more P fertilizer application. In addition, due to the lower PSI value in the eastern half of the study region, applying less fertilizer at more frequent intervals seems to be more beneficial than larger single applications. Eventually, to reduce environmental risks and prevent the loss of natural resources, the method of applying P fertilizer needs to be mainly based on the created PSI distribution map.  相似文献   

15.
陈贵  张红梅  沈亚强  程旺大 《土壤》2018,50(1):59-65
采用连续5年田间定位试验,研究了等量单独施用猪粪或牛粪有机肥以及有机肥与化学肥料配施对水稻产量、氮磷钾养分吸收累积及利用效率、土壤养分含量及其与产量等关系的影响。结果表明:猪粪有机肥施用(7.5t/hm~2+常量化肥、15 t/hm~2+1/2常量化肥和30 t/hm~2+无化肥)时水稻产量、干物质累积、氮磷累积及生理利用效率与常量化肥处理相比无显著差异;牛粪有机肥与化肥减量配施和单独施用时,尽管氮、磷和钾生理利用效率有所提高,但水稻产量、地上部氮、磷和钾累积量均有不同程度下降,且以单独施用时尤为明显。等量猪粪有机肥对土壤全氮、碱解氮、有效磷和速效钾含量以及pH的提升程度大于牛粪有机肥,有机质含量无明显差异;与猪粪有机肥相比,牛粪有机肥施用时土壤养分各指标与水稻产量、干物质累积量、氮磷钾累积量以及利用效率间的相关性更为明显,其中与产量、干物质累积量和氮磷钾累积量极显著负相关,与氮磷钾生理利用效率显著正相关。因此,等量猪粪有机肥和牛粪有机肥的肥效存在较大差异,在实际生产中应根据不同源有机肥特性进行调节施用。  相似文献   

16.
不同动物排泄物氮的作物利用及对N2O排放的贡献   总被引:3,自引:1,他引:3  
李晓 《土壤》2008,40(4):548-553
本文用同一种土壤,在不同水分管理模式下,种植两种作物,以不施 N 作为对照研究了人粪、猪粪、奶牛粪和鸡粪作肥料与尿素等 N 量施用,对小米和水稻籽粒产量、N 素利用率的影响以及对N20排放量的贡献.尿素与4种粪肥对小米和水稻产量、N素利用率和N20排放的贡献并不相同.水稻产量以施用尿素最高,施用鸡粪产量效应最低,与不施N处理接近,但旱作小米以施用人粪最高,其次为尿素和鸡粪处理.水稻和小米对N素的回收率均以尿索为最高,其次为人粪、鸡粪和牛粪,猪粪最低.尿素和4种粪肥处理,在小米播种和水稻移栽后的第2天均出现了N20的排放高峰.由于两种作物水分管理不同,N20排放高峰持续时间不同,水稻长于小米.在水稻烤田前后的干湿交替过程中,不同肥料处理均出现了N20的第2次排放高峰,除牛粪和猪粪处理外,N20 峰值的持续时间长达10天左右.N20排放总量在旱作小米生长季以人粪处理最高,尿素,鸡粪和猪粪处理接近,牛粪处理最低.水稻生长季N20排放量以尿素处理为最高,依次为人粪、鸡粪处理和猪粪处理,牛粪处理最低,与不施N处理接近.  相似文献   

17.
Abstract

Soil chemical and physical reactions involving phosphorus (P) must be understood to predict the risk of P being transported from agricultural land to streams and lakes. The kinetics of P sorption by an Ultisols from West Virginia, USA, receiving P from fertilizers were compared to soils amended with turkey litter. Addition of 6.6 and 13.2 Mg turkey litter ha?1 increased Bray 1P levels to about the same level as adding 53 and 115 kg P ha?1, respectively. Phosphorus binding capacity decreased to a greater extent when P was added as fertilizer as compared to turkey litter. For example, P binding maximum was 360 mg P kg?1 dry soil when soil was amended with 6.6 Mg turkey litter ha?1 as compared to 260 mg P kg?1 dry soil when amended with 53 kg P ha?1. This study demonstrates that the decrease in P‐binding capacity with increasing soil P is less when P is added as turkey litter.  相似文献   

18.
More than 40% of soils in the Transkei region, South Africa, have high phosphorous (P) fixation capacities that necessitate application of high P fertilizer rates. This incubation study compared the effectiveness of goat manure (GM) and lime to minimize P sorption in two such soils. Manure application reduced P sorption in both soils, which was partly attributed to the liming effect of GM that resulted in marked reductions of exchangeable aluminum (Al). The liming effect of GM rates followed the order 20 t GM ha?1 > 10 t GM ha?1 > 5 t GM ha?1. Therefore, GM can be cost‐effectively used to lime acid soils in the region and reduce their Al toxicity potential and P fertilizer requirements. Liming reduced P sorption on the Chevy Chase soil soon after application, but P sorption was reduced after 2 months on the Flagstaff soil, suggesting that the timing of liming for improved P availability could be critical for some soils.  相似文献   

19.
The term biochar refers to materials with diverse chemical, physical and physicochemical characteristics that have potential as a soil amendment. The purpose of this study was to investigate the P sorption/desorption properties of various slow biochars and one fast pyrolysis biochar and to determine how a fast pyrolysis biochar influences these properties in a degraded tropical soil. The fast pyrolysis biochar was a mixture of three separate biochars: sawdust, elephant grass and sugar cane leaves. Three other biochars were made by slow pyrolysis from three Amazonian tree species (Lacre, Ingá and Embaúba) at three temperatures of formation (400 °C, 500 °C, 600 °C). Inorganic P was added to develop sorption curves and then desorbed to develop desorption curves for all biochar situations. For the slow pyrolysis, the 600 ºC biochar had a reduced capacity to sorb P (4–10 times less) relative to those biochars formed at 400 °C and 500 °C. Conversely, biochar from Ingá desorbed the most P. The fast pyrolysis biochar, when mixed with degraded tropical mineral soil, decreased the soil's P sorption capacity by 55% presumably because of the high soluble, inorganic P prevalent in this biochar (909 mg P/kg of biochar). Phosphorus desorption from the fast pyrolysis biochar/soil mixture not only exhibited a common desorption curve but also buffered the soil solution at a value of ca. 0.2 mg/L. This study shows the diversity in P chemistry that can be expected when biochar is a soil amendment and suggests the potential to develop biochars with properties to meet specific objectives.  相似文献   

20.
Phosphorus sorption and desorption processes in selected soils were investigated to evaluate the usefulness of phosphorus sorption isotherms in the estimation of the phosphorus supplying capacity of soils. There was a distinct hysteresis in the phosphorus sorption and desorption isotherms, resulting in an overestimation of the replenishing ability of soils to supply phosphorus to the soil solution, when phosphorus sorption isotherms were used for the estimations.

To attain a value of 0.2 ppm P in the soil solution, 115 µmol P/g soil are required in the Kuromatsunai Ando soil (Ochric Andosols) based on the estimation by the P desorption isotherms; this value is 29% higher than that indicated by the P sorption isotherm. Also 42 µmol P/g soil are required in the Mikatagahara Yellow soil (Helvic Acrisols)—which corresponds to a value 23% higher than that indicated by the P sorption isotherm.

Two types of hysteresis subloops were observed: A reversible type and an irreversible type. The former was found typically in the highly weathered Mikatahagara Yellow soil while the latter was observed in the Kuromatsunai Ando soil.  相似文献   

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