施硅对水稻土磷素吸附与解吸特性的影响研究

研究了水稻土中施Si对P吸附与解吸特性的影响。结果表明 ,由于土壤中Si、P存在着竞争性吸附 ,当Si施入土壤时 ,它必然占据一部分Si、P共用的吸附点位 ,降低了土壤中P的吸附量。施Si对P解吸量的影响比较复杂 ,在低P浓度 (10、20、30mg/kg)时 ,施Si增加了P的解吸量 ;在高磷浓度 (40mg/kg)时 ,施Si后P的解吸量变化不大 ,而P浓度为 50mg/kg时 ,P的解吸量随Si的施加呈下降趋势。表明Si减少P吸附量的同时 ,也由于降低了土壤对P的吸附结合能 ,而增加了易解吸P的含量。施Si明显的提高了土壤P的解吸率     

土壤对铜的吸附-解吸特征及对土地利用的响应

用吸附平衡法研究黄河三角洲地区土壤对Cu2+的吸附和解吸特征,对比了农田和未利用地土壤吸附与解吸能力的差异,并分析了差异形成的原因。结果表明,土壤对Cu2+的吸附量随着平衡液Cu2+质量浓度的增加而增加,其吸附作用可用Langmuir,Temkin和Freundlich方程来拟合,以Langmuir方程拟合结果最佳。根据Langmuir方程计算出的两种土壤最大吸附量分别为3 961mg/kg和3 521mg/kg,农田土壤对Cu2+的吸附能力强于未利用地土壤;土壤Cu2+的解吸量远远小于土壤对Cu2+的吸附量,与农田土壤相比,未利用地土壤Cu2+的解吸有滞后现象;农田土壤和未利用地土壤Cu2+的解吸率变化范围分别为0.1%～0.35%和0.15%～1.8%,农田土壤的解吸率明显低于未利用地土壤。综合分析认为,两种土壤吸附—解吸特征的差异与农田土壤具有较高的有机质含量,从而在土壤胶体表面形成较多的吸附位点有关。     

不同水分状况及施磷量对水稻土中速效磷含量的影响

通过室内培养试验研究了不同水分(淹水和60%田间持水量)及施P量对水稻土速效P及水层含P量的影响。结果表明,无论水分状况如何,土壤速效P含量随施P量的增加而呈明显增加趋势。土壤速效P出现富集的转折点因供试土壤而异,第三纪红壤性水稻土大致为P2O560~120mg/kg,而第四纪红壤性水稻土和黄泥土为P2O5120~180mg/kg。P肥施入土壤后,水溶性P主要存在于土壤溶液中,而分布于水层中的P相对较少。但在过量施P(P2O5>180mg/kg)时,施肥后短期内(0~30天),水层中P浓度较高(0.05~0.3mg/kg),如水分管理不当,则会造成P的损失。     

淹水对石灰性土壤无机磷形态转化的影响

  【目的】  磷肥施入土壤后大部分转化为与铁氧化物关系密切的Fe-P和O-P,而淹水后土壤中铁的氧化还原过程可能影响与铁氧化物结合的磷的形态及有效性的变化。研究不同施磷处理下淹水土壤Fe (II) 、无机磷组分等的变化,以期明确淹水后土壤无机磷形态及磷有效性变化及其与铁氧化还原过程的关系。  【方法】  用不施磷土壤 (P0) 和连续6年施用P 180 kg/hm2的土壤 (P180) 进行室内模拟培养试验。将土壤装于西林瓶内,加水模拟淹水条件,西林瓶密封后,分别在避光或者光照条件下,于 (30 ± 1)℃恒温培养40天。测定供试土壤以及淹水培养土壤中的速效磷、无机磷以及不同形态无机磷组分含量,测定培养过程Fe (II) 的动态变化,以探讨磷形态转化与铁氧化还原过程的关系。  【结果】  施用磷肥显著增加土壤中的速效磷含量和无机磷总量,P0处理土壤速效磷含量为 (7.65 ± 1.65) mg/kg,P180处理土壤速效磷含量高达 (33.5 ± 2.01) mg/kg。施入土壤中的磷只有很小部分以Ca₂-P存在,主要以Ca₁₀-P、Ca₈-P、Al-P和Fe-P形态存在。避光淹水培养后,土壤速效磷含量增加,P0和P180处理土壤速效磷含量的增量分别为8.44、2.95 mg/kg。淹水培养降低了土壤Ca₈-P含量,提升了Fe-P、O-P、Al-P含量。光照和避光条件下P180处理土壤中Ca₈-P含量分别降低106.8、156.2 mg/kg,Fe-P含量分别增加23.4、47.0 mg/kg,O-P含量分别增加64.1、92.9 mg/kg,Al-P含量分别增加38.8、34.7 mg/kg,避光时Ca₈-P降幅以及Fe-P和O-P的增量均大于光照条件下。避光条件下,铁还原量和还原最大速率与Ca₈-P变化量之间存在显著负相关关系,与Fe-P、O-P增量之间存在显著正相关关系。  【结论】  淹水条件下,石灰性土壤中的Fe (Ⅲ) 还原形成Fe (Ⅱ) 和Fe (Ⅲ) 混合物,增加了铁氧化物的比表面积和磷吸附点,可促进Ca₈-P向O-P、Fe-P和Al-P转化。光照降低了Fe (Ⅲ) 的还原量,可能是Ca₈-P向O-P、Fe-P和Al-P转化率低的原因之一。     

不同质地棉田土壤对磷吸附与解吸研究

研究了不同质地棉田土壤对磷吸附与解吸的影响。结果表明:不同质地磷素等温吸附曲线与Langmuir、Temkin和Freundlich方程拟合度都达极显著水平,尤以Langmuir方程拟合度最高,相关系数均在0.94以上;磷吸持指数(PSI)、土壤最大缓冲容量(MBC)和吸附量均随粘粒含量的增加而增大,即粘土壤土砂壤土,而易解吸磷(RDP)、解吸量、解吸率和标准需磷量(SPR)呈下降趋势,即砂壤土壤土粘土。以Langmuir方程估算棉田土壤的需磷量,砂壤质棉田需磷量为12.87mgkg-1,壤质棉田需磷量为12.66mgkg-1,粘质棉田需磷量为10.00mgkg-1。     

不同pH下黄棕壤镉的吸附-解吸特征

对黄棕壤在pH2 7不同浓度下Cd2 的吸附与解吸进行了测定。结果表明,Cd2 吸附量随平衡液中Cd2 浓度增加而增大,两者关系较好地符合Langmuir吸附方程。根据吸附等温线参数与pH的相关方程,得到镉吸附等温线的pH依存模式,如Langmuir方程为:C/X=69 334e-1 7183pH (5 5793pH-3 0383)·C。式中,X为土壤Cd2 吸附量(mg/kg),C为平衡液中Cd2 之浓度(mg/L)。解吸Cd2 的数量随pH升高和吸附Cd2 的数量增加而增加,但解吸Cd2 占吸附Cd2 的比例随pH升高而降低,在pH3 7下,黄棕壤解吸Cd2 的比例为42%～95%,平均为75%,说明黄棕壤Cd2 以非专性吸附为主,吸附Cd2 的有效性高。     

不同施磷处理下棉田土壤磷素吸持特征研究

为探究不同施磷水平对棉田土壤磷的固定和释放机制,对新疆典型棉田5种施磷水平(P0、P75、P150、P300、P450)及不同层次(0～5、5～10、10～20、20～40、40～60 cm)的灰漠土进行磷素吸附和解吸特性研究,结果表明:土壤磷吸附量随磷肥施用量的增加先增加后减小,以P150处理吸附量最大,P0和P75处理吸附量较小,其中P150处理最大吸附量较P0处理增加了45%;随土层深度的增加,各处理吸附量逐渐增大,处理间吸附量的差异逐渐减小,40～60 cm土层最大吸附量为0～5 cm土层的2.10倍。土壤磷的等温吸附曲线与Langmuir、Freundlich和Temkin方程的拟合度都达显著水平(P0.05),土壤最大吸附量(Xm)与等温吸附曲线一致,以0～5 cm土层P75处理最小,为476.19 mg·kg~(-1),随土层深度增加而增加,吸附常数(K)与Xm呈相反趋势;随施磷量的增加,土壤最大缓冲容量(MBC)呈增加趋势,深层土壤小于表层土壤;土壤磷素吸附饱和度(DPS)以P75处理最大,整体随土层深度的增加而减小。土壤磷解吸量与解吸率随吸附能力的增加而减小;土层越深,解吸量与解吸率越小,其中0～5 cm土层解吸量为40～60 cm土层的2.06倍。增施磷肥能够提高棉田土壤贮存磷的能力,施磷量75 kg·hm~(-2)降低土壤对磷的吸附能力,增加土壤对磷的解吸,深层土壤磷的吸附特性受施肥水平的影响较小,供磷能力小于表层土壤。     

间作对红壤磷素吸附解吸平衡效应的影响

磷素的吸附和解吸特性对土壤磷素迁移及其环境效应具有重要影响,过量磷肥施入易造成土壤磷素固定和流失,但合理间作可促进磷素吸收利用,减少固定,研究间作和不同施磷量条件下红壤磷素吸附解吸特性的平衡效应对促进红壤磷的高效利用,兼顾环境效应具有重要意义。本研究采取2因素裂区区组试验,主因素为种植模式,分别为与玉米||大豆(IM)、单作玉米(MM);副因素为施磷水平,分别为P0 [0 kg(P_2O_5)·hm~(-2)]、P60 [60 kg(P_2O_5)·hm~(-2)]、P90 [90 kg(P_2O_5)·hm~(-2)]、P120 [120 kg(P_2O_5)·hm~(-2)] 4个施磷水平,通过田间试验,研究间作和施磷量对红壤磷素吸附解吸平衡效应的影响;应用结构方程模型(SEM)和邻接树法(ABT)定量分析间作和施磷水平对磷吸附和解吸的相对贡献,揭示间作影响红壤磷素吸附解吸的关键因子。结果表明:1) Langmuir等温吸附方程最适合红壤对磷的吸附特征拟合,土壤磷吸附量随平衡溶液磷浓度的增加呈先增加再趋于饱和的趋势,土壤磷吸附量随施磷量的增加逐渐降低。2)种植模式和施磷水平以及交互作用极显著(P0.01)影响红壤磷素的吸附量和解吸量。间作处理较单作磷素吸附量和解吸量分别增加22.9%和9.2%(P0.05);不同施磷水平下,间作磷吸附量较单作显著增加13.0%、19.4%、41.5%和23.9%(P0.05);磷解吸量在P0和P60处理间作较单作显著增加90.2%和194.4%(P0.05),而在P90和P120处理间作较单作减少52.1%和34.1%(P0.05)。3)不同种植模式与施磷水平下,土壤磷吸附量与土壤pH、有机质、树脂磷、有效磷、全磷以及磷吸附饱和度呈极显著负相关(P0.01),与游离氧化铁、游离氧化铝和磷吸持指数呈极显著正相关(P0.01),土壤磷解吸量与标准需磷量呈极显著负相关(P0.01)。红壤磷素的吸附和解吸主要受pH、有机质和游离氧化铁的影响,间作通过改变土壤的pH、有机质和游离氧化铁含量影响红壤磷吸附量和解吸量。玉米||大豆间作具有较好的土壤磷缓冲能力,低磷水平下促进磷素大量解吸供植物吸收利用,高磷水平下促进磷素吸附有效减缓磷素的损失。     

未开垦干扰黑土土壤磷的吸附与解吸垂直变化特征

以天然次生林土壤为对象,通过对0~180 cm土层范围内土壤磷的最大吸附量(Qm)、最大吸附缓冲容量(MBC)、解吸量及解吸率等指标的测定、计算和分析,研究了典型黑土区未经开垦干扰黑土磷的吸附与解吸特性在垂直空间上的变化特征。结果表明:不同层次土壤对磷的等温吸附与解吸数据与Langmuir方程的拟合程度均达到极显著水平(p0.01);Qm在垂直空间上的变化范围为442.21~857.23 mg kg-1,且随土层深度的增加表现为先增加后降低又增加的趋势;磷的吸附饱和度(DPS)则表现出相反的趋势,且不同层次之间差异显著(p0.05);不同土层土壤磷的解吸量和解吸率均随平衡液浓度的提高而增加;土壤磷的解吸比率(Dr)和易解吸磷(RDP)含量均以0~20 cm土层较大。可以认为未开垦干扰黑土0~20 cm土层土壤供磷能力较强,随着土壤深度的增加,磷的有效性呈现一定程度的降低。研究结果不仅为黑土区土壤磷的系统研究提供了本底资料,而且可为该区土壤质量评价提供参考。     

不同有机肥对煤矿复垦土壤磷吸附解吸特性的影响

【目的】石灰性复垦土壤磷素含量极低且易被其他离子吸附固定,严重影响作物的吸收与利用。研究不同有机肥对石灰性复垦土壤磷吸附解吸特征的影响,为加速培肥煤矿复垦土壤提供技术和理论依据。【方法】在山西省孝义市采煤塌陷区进行了4年的定位培肥试验,共设置了6个处理：不施肥、施鸡粪、施猪粪、施牛粪和氮钾肥、施氮磷钾肥。采集各处理土壤样品进行吸附动力学试验,测定复垦土壤磷最大吸附量、最大缓冲容量、吸附饱和度、解吸率,并分析影响磷吸附解吸的关键因素。【结果】采用Langmuir等温吸附方程可以极好地拟合复垦土壤对磷的吸附(R²=0.924～0.992)。复垦年限和施肥处理以及二者的交互作用均对复垦土壤磷吸附解吸产生显著影响。随复垦年限的增加,土壤磷最大吸附量显著降低,而土壤磷吸附饱和度和解吸率显著增加。与复垦第1年相比,复垦第4年各施肥处理的土壤磷最大吸附量降低了12%～26%,土壤磷吸附饱和度增加了218%～885%,土壤磷解吸率增加了86%～118%。与两个化肥处理相比,3种有机肥处理下土壤磷最大吸附量显著降低了30%,最大缓冲容量降低了31%,土壤磷吸附饱和度增加了34%,磷...     

Correlation of solution and extractable phosphorus with vegetative growth of teff

Abstract

Three soils, Hiwassee loam (clayey, kaolinitic, thermic, Typic Rhodudults), Vaiden clay (very fine, montmorillonitic, thermic, Vertic Hapludalfs) and Marvyn sand (fine, loamy, siliceous, thermic, Typic Hapludults), were used in this study. Phosphorus sorption and desorption isotherms of the soils were determined in the laboratory. Average P sorption maximum (b) was calculated using the Langmuir isotherm equation. Based on the P sorption capacity, each soil was fertilized with different P rates and teff [Eragrostis tef (Zucc)] was grown in the greenhouse. The amount of P sorbed and desorbed increased as the concentration of equilibrating solution P increased. Phosphorus sorption maximum from sorption and desorption isotherms was 278, 251, and 37 mg P/kg for Hiwassee, Vaiden, and Marvyn soils, respectively, and for maximum dry matter yield of teff the soils needed a minimum of 0.029, 0.048, and 0.065 mg/L soil solution P, respectively, which were all below the soil solution P at P adsorption maximum.

Soil P was extracted by the Mehlich I, Mehlich III, modified Mississippi, Bray P‐l and Olsen methods. Plant‐available P extracted by each of the five methods was significantly correlated with teff dry matter yield, and statistically any of the five methods can be used as the basis for predicting teff yield responses.     

Phosphorus Adsorption Saturation of Ferrihydrate as an Index of Phosphorus Availability to Paddy Rice

ABSTRACT

The characteristics of phosphorus (P) sorption/desorption of artificially synthesized ferrihydrate and the relationship between P adsorption saturation of ferrihydrate, rice growth, and P uptake by rice (Oryza sativa L.) were studied. The results obtained from experiments showed that the artificially synthesized ferrihydrate had a very large adsorption potential to P, with 45045 μg P g^?1 of maximum adsorption capacity (Qm). Phosphorus adsorption isotherm of ferrihydrate could be fitted very well with the Langmuir equation. Desorption of P adsorbed by ferrihydrate was controlled mainly by P adsorption saturation of ferrihydrate. Phosphorus adsorbed by ferrihydrate with saturation of less than 30% was hardly desorbed. Phosphorus desorption slowly increased with the increase of P saturation from 30% to 60%, but sharply increased with P saturation of greater than 60%. Thus it could be seen that P adsorption saturation should be a key factor affecting the availability of P adsorbed by iron oxides and be a better index than the quantity of oxalate-extractable P in estimating P phyto-availability in flooded soils. A Bioassay using rice indicated that 50% of P adsorption saturation could be used as a critical index for diagnosing status of P supplied by ferrihydrate-bonded P at the tillering stage of rice.     

风化煤腐殖酸对氮、磷、钾的吸附和解吸特性

研究了风化煤腐殖酸在不同pH值条件下对氮、磷、钾的吸附和解吸特性。结果表明,1)在pH.4～8条件下,随着氮、磷、钾初始处理浓度的增加,腐殖酸对其吸附量和解吸量均呈上升趋势,但解吸率均呈下降趋势;2)在不同pH值的介质溶液中,腐殖酸对氮、磷、钾的吸附和解吸特性不尽相同,其中,在碱性条件下,腐殖酸对氮的吸附和解吸作用较强,在酸性条件下,腐殖酸对磷的吸附和解吸作用较强,而腐殖酸对钾的的吸附和解吸作用在中性条件下更易发生;3)腐殖酸对氮、磷、钾的等温吸附可用Linear、Langmuir和Freundlich三个吸附方程来拟合,相关性达显著或极显著水平,但以Freundlich方程为最优。     

磷的吸附和表面电荷特征及其与华南地区某些土壤矿物的关系

The phosphate adsorption and surface charge characteristics of the tropical and subtropical soils derived from different parent materials in China were determined, and their relations to soil mineralogy were analysed. The results showed that all soil phosphate adsorption curves were well fitted by Freundlich equation and Langmuir equation. The maximum buffering capacity of P ranged from 66 to 9 880 mg kg^-1, with an increasing order of purple soil, skeletal soil, red soil, lateritic red soil, yellow soil and latosol; and the highest value was 149 times the lowest value, which indicated great differences among these soils in phosphate adsorption and supplying characteristics. The pH₀ (zero point of charge) values obtained by salt titration-potential titration varied from 3.03 to 5.49, and the highest value was found in the latosol derived from basalt whereas the lowest value was found in the purple soil. The correlation analysis indicated that the main minerals responsible for phosphate adsorption in the soils were gibbsite, amorphous iron oxide and kaolinite; and the pH₀ was mainly controlled by kaolinite, gibbsite and oxides.     

冻融作用对棕壤磷素吸附-解吸特性的影响

以棕壤为研究对象,采用室内模拟冻融环境的方法,研究土壤磷素吸附-解吸行为,采用Langumuir、Freundlich和Temkin方程对吸附过程进行拟合分析,定量研究冻融作用对土壤磷素吸附机制的影响,同时建立土壤磷素解吸量与吸附量关系方程,进一步探讨冻融土壤磷吸附-解吸特性。结果表明,冻融条件下棕壤对磷的吸附规律一致,吸附量均随着平衡溶液中磷浓度增加而逐渐增大,与未冻融土壤相比,冻融后土壤磷等温吸附曲线变得平缓。冻融条件下磷等温吸附曲线用Langmuir方程拟合相关性最好。土壤磷素解吸量与相应最大吸附量符合线性相关。冻融后土壤磷固定吸附量低于未冻融土壤,即冻融过程促进土壤磷素释放,增加了土壤磷流失风险。多次冻融循环对土壤磷吸附-解吸行为影响更为强烈。     

磷的吸附对老成土和淋溶土中Cu、Zn离子吸附-解吸及其有效性的影响

Surface charge,secondary adsorption-desorption and form distribution of Cu^2 and Zn^2 in Ultisols and Alfisols having adsorbed phosphate were studied by potentiometric titration,adsorption equilibrium and sequential extraction method,respectively,The soil surface negative charges increased whereas the amount sequential extraction method,respectively.The soil surface ngative charges increased whereas the amount of positive charges decreased with increase of P adsorbed,The soil secondary adsorption capacity for Cu^2 and Zn^2 was positively significantly correlated with the amount of P adsorbed by the soils,which could be described by the Langmuir equation.The amounts of Cu^2 and Zn^2 desorption from soils were decreased after P adsorption by the soils and the relationship between them was linear,After the soils adsorbed P,form distribution of Cu^2 and Zn^2 in soils changed remarkably.     

Phosphorus requirement of corn and sunflower grown on calcareous soils of Pakistan

Abstract

Determining phosphorus (P) fertilizer requirement through sorption isotherms is considered more accurate than conventional soil testing. Phosphorus sorption isotherms were constructed by using the Missa (Typic Ustochrept), Gujranwala (Udic Haplustalf), Abbotabad (Aquic Entrochrept), and Rasulpur (Ustochreptic Camborthid) soil series which varied in their calcium carbonate (CaCO₃) and clay contents. Quantities of fertilizer‐P (mg P/kg soil) required to adjust the standard soil solution P concentration (0.2 mg P/L) were: Missa, 83; Gujranwala, 51; Abbotabad, 50; and Rasulpur, 8. Langmuir model conformed better with the adsorption data than Freundlich model and indicated that the order of maximum adsorption capacity (b) was: Missa > Abbotabad = Gujranwala > Rasulpur. The P sorption curves were used to develop the soil solution P concentration in the Gujranwala and Missa soils varying from native to 0.5 mg P/L. Soil solution P requirement of corn and sunflower for near‐maximum (95%) biomass production was approximately the same, 0.32 mg P/L. Internal P requirement in whole shoots (≤30 cm tall) were 0. 29% for corn and 0.39% for sunflower.     

冻融作用对东北黑土磷素吸附-解吸过程的影响

冻融作用对土壤理化性质具有重要影响,从而影响土壤中磷素的吸附—解吸特性。以东北黑土为研究对象,采用室内模拟冻融环境的方法,研究了冻融条件下黑土磷素吸附—解吸行为。结果表明,冻融条件下黑土对磷的吸附规律均随着外源磷浓度增加而逐渐增大,当外源磷浓度为120mg/L时吸附曲线出现明显拐点;与未冻融土壤相比,冻融过程中土壤吸附更多的磷,具有更高的磷素吸附率;外源磷浓度低时,冻融作用对土壤磷吸附影响较大,外源磷浓度高时冻融作用对土壤磷吸附影响降低;冻融条件下磷等温吸附曲线采用Langmuir方程拟合的相关性最优,在连续的冻融循环条件下,土壤磷最大吸附量Pmax值逐渐增大,土壤与磷之间结合能力和磷吸附最大缓冲容量也有同样的趋势。     

Effect of phosphorus competition on arsenic bioavailability in dry and flooded soils: comparative study using diffusive gradients in thin films and chemical extraction methods

Purpose

Phosphorus influence on arsenic bioavailability in soils and its toxicity to plants is widely recognized. This work compares competitive influence of P on As bioavailability in dry and flooded soils.

Materials and methods

Pot experiments were carried out in dry and flooded soils, respectively. Bioavailable As in soils was measured using diffusive gradients in thin films (DGT), soil solution concentration, and three single chemical extraction methods.

Results and discussion

P concentration at 50 mg/kg promoted wheat growth in dry soil. At concentrations above 50 mg/kg, P competition inhibited wheat growth and enhanced As toxicity. In flooded soil, the rice height and biomass decreased with the increase of P addition. P concentrations above 800 mg/kg were lethal to the rice. The content of As absorbed by wheat and rice roots as well as shoots increased with the increase of P concentration. The bioavailability of As in wheat- and rice-grown soils, determined by all methods, also increased with the increase of P concentration. The correlation analysis between the bioavailable As measured by the all three methods and the content of As in plants showed a significant positive correlation. The Pearson correlation coefficient for the DGT method was higher comparing to all other methods. DGT-induced fluxes in soils (DIFS) modeling further showed sharp decreases of T_c (the characteristic time to reach equilibrium between available solid As pool and soil solution As from DGT perturbation) and increases of desorption and adsorption rate constants (k₁ and k_?1) of As in P-amended soils, reflecting that the kinetic release of As from available solid As pools became much easy from P competition.

Conclusions

P competition in both dry and flooded soils could significantly increase bioavailability of As and further increase its toxicity. Competition effect was more pronounced in flooded soil. DGT is a more accurate method for As bioavailability evaluation in both dry and flooded soils.

     

模拟酸雨对荔枝果园土壤磷素等温吸附与解吸特性的影响

采用等温吸附试验方法研究了模拟酸雨对荔枝果园土壤磷的吸附与解吸特性的影响。试验结果表明,不同处理间土壤对磷的最大吸附量(Xm)为pH2.5>pH4.5>CK=pH6.5,其中pH2.5的酸雨淋溶处理对磷的最大吸附量(Xm)与其它处理间差异显著;土壤吸附磷的解吸量(Xd)分别与相应的吸附量(X)和原平衡溶液浓度(C)呈显著的指数相关和线性相关,随着土壤对吸附量的增加,土壤磷的解吸量呈指数增长。