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1.
磷肥和有机肥对不同磷水平土壤磷渗漏影响研究   总被引:1,自引:0,他引:1  
采用土柱培养的模拟试验方法研究了在不同磷水平土壤上大量施用磷肥和有机肥对土壤测试磷、土壤磷渗漏的影响及影响机理。结果表明,不同磷水平土壤施用磷肥或有机肥土壤CaCl2-P、Olsen—P和土壤渗漏液中可溶性磷均显著增加;单位量磷肥或有机肥所增加土壤各形态磷量随土壤磷水平的增加而增大;随着磷肥或有机肥用量的增加,单位量磷肥或有机肥所增加各形态磷量也逐渐增大,差异均达到显著和极显著水平。在施用磷肥的基础上增施有机肥可以提高土壤CaCl2-P、Olsen—P含量和土壤渗漏液中可溶性磷的增长幅度。土壤磷的渗漏量与土壤测试磷呈显著正相关;单位量磷肥或有机肥所增加的土壤渗漏磷量随着磷肥或有机肥用量以及土壤磷水平的增加而增加。Olsen—P含量与土壤磷吸持指数(PSI)呈显著负相关关系,与土壤磷的吸附饱和度(DPS)呈显著正相关关系。  相似文献   

2.
Abstract

Bray 1 phosphorus (B1P) and sequential phosphorus (P) fractions were determined on soils treated with triple superphosphate (TSP), Gafsa (GPR), and Christmas Island phosphate rocks (CIPR), respectively, with and without manure. The fractions extracted in decreasing lability were iron oxide–impregnated paper strip P (Pi‐strip P), inorganic (Pi), and organic (Po) bicarbonate (NaHCO3‐Pi and ‐Po), hydroxide [sodium hydroxide (NaOH)‐Pi and ‐Po], hydrochloric acid (HCl) P, and residual (residue P). The magnitude of B1P was in the order TSP>GPR=CIPR. Average B1P from PRs was two‐fold the amount in TSP, whereas that of the fractions was NaOH‐P>Residue P<sodium bicarbonate (NaHCO3) P<Pi‐strip P <HCl. Bray 1 extracted mainly the most labile fractions (Pi‐strip P and NaHCO3‐Pi), and plant P uptake was correlated mainly to NaOH‐Po and NaHCO3‐Pi. Magnitude of various fractions differed between TSP and PRs. Both B1P and the fractions were equally correlated to P uptake (R2=0.38**). Nevertheless, sequential fractionation appears to be a powerful tool to identify the P status and availability in soil.  相似文献   

3.
土壤有机酸与磷素相互作用的研究   总被引:23,自引:1,他引:23  
胡红青  李妍  贺纪正 《土壤通报》2004,35(2):222-229
土壤有机酸包括低分子量有机酸和腐殖酸,它们构成土壤有机组分中性质较活跃的部分。特别是低分子量有机酸,在土壤形成、养分和污染物的转化过程中起着十分重要的作用,受到土壤、植物营养和环境科学工作者的高度重视。本文着重从它们与磷素相互作用的角度,阐述有关研究进展。主要内容包括:(1)磷营养与植物根系分泌有机酸的特征;(2)有机酸对土壤吸附磷的影响;(3)有机酸与磷的解吸、释放与转化。旨在促进研究工作的深入,并为合理利用磷素,保护生态环境提供科学依据。  相似文献   

4.
施磷对滨海盐土无机磷组分的动态影响   总被引:1,自引:0,他引:1  
采用蒋柏藩、顾益初提出的土壤无机磷组分测定方法,在50d的培养过程中对滨海盐土的各无机磷组分进行了跟踪测定。结果表明:施入盐土中的无机磷在短期内主要增加土壤中的Ca2-P和Ca8-P的含量,而对A1-P、Fe-P和O-P的影响较小;施入盐土的无机磷首先转化成Ca2-P,然后再向Ca8-P、Ca10-P、Al-P、Fe-P和O-P转化;培养过程中,水分和温度的有利条件促进了土壤微生物的活动,加强了微生物对无机磷的固定。  相似文献   

5.
设施蔬菜种植中存在不合理施肥现象,土壤养分严重失调。为了解设施蔬菜地高氮肥力水平下不同氮素水平对磷素的养分吸收影响,2004—2007年在山东寿光进行不同氮素水平调控和秸秆还田试验,并于2007年冬春季进行裂区淋滤试验。结果表明,不同水平的氮素调控影响磷素含量变化,空白(NN)、有机肥(MN)、有机肥+秸秆(MN+S)供氮水平下土壤全磷含量逐年下降,降幅NNMNMN+S,全磷增幅传统氮素(CN)传统氮素+秸秆(CN+S)氮素优化+秸秆(SN+S)氮素优化(SN)。CN、CN+S供氮水平下土壤速效磷含量达到213.7、225.4 mg·kg-1,增长了17.1%、23.5%,磷素累积明显;其他供氮水平下速效磷含量逐年下降,降幅NNMNMN+SSN+SSNCNCN+S,减少氮素供应有利于减缓磷素累积,促进磷的吸收利用。除NN供氮水平下土壤有机磷含量下降外,其他处理均不同程度增加,CN、CN+S供氮水平下土壤有机磷含量累积明显(308.4、331.4 mg·kg-1),分别增长了28.5%、38.2%。SN+S供氮水平下磷的吸收系数(P2O5,mg·100 g-1)达到了1 571,增长了143.6%;CN、CN+S供氮水平下磷的吸收系数出现了负增长,CN供氮水平下达到了416(P2O5,mg·100 g-1),下降了35.5%。添加小麦秸秆极大地提高了磷的吸收能力,在一定程度上能减缓土壤速效磷的累积。淋溶液中全磷含量SNSN+S,有机磷含量SNSN+S,秸秆还田对阻控有机磷素淋溶有一定的作用,但整个冬春生长季渗滤液中全磷含量在2.6~12.0 mg·L-1,有机磷含量在0.42~4.1 mg·L-1,淋出液水质仍超过了国家安全水质标准。因此,在高肥力水平下进行氮素调控,优化氮素供应量,促进了磷素的吸收利用,对农民在高肥力水平下施肥具有指导意义。建议农民在以后的种植中减少氮肥供应量及添加高碳源秸秆进行还田,以提高肥料的利用率,减少氮磷对土壤及水体的污染。  相似文献   

6.
ABSTRACT

Most of the sugarcane (interspecific hybrids of Saccharum sp.) production in Florida is on organic soils. Supplemental phosphorus (P) fertilizer is often applied for optimum yields, but producers are required to reduce P levels in farm drainage waters. The objectives of this study were to relate optimum leaf P tissue concentration with yield in organic soil, and to determine optimum leaf sampling dates during the summer. Eight genotypes were planted at two locations, eight additional genotypes were planted at a third location, and eight more genotypes were planted at a fourth location. Crops were grown for three years. Measurements of leaf P concentration were repeated during growth seasons and over crop years for a total of six sampling dates at each location. Three fertilizer P treatments (0, 24, and 48 kg ha?1 yr?1) were applied to all genotypes at each location. Leaf samples were partitioned into early-, mid-, and late-summer dates. Early-leaf samples had the widest range in leaf P concentrations compared with mid- and late-season leaf samples. Correlation analyses of yield vs. leaf P concentration across all treatments in early- and mid-summer were statistically significant (P < 0.05), but coefficients were low (r = 0.14 and 0.26, respectively). No consistent relationship across locations described the effect of leaf P tissue concentration on yield. Leaf P concentrations could not provide accurate P fertilization rates that will give maximum sugarcane yields and prevent over-fertilization of P. The highest potential for relating leaf P concentrations with yield appears to be from early leaf samples.  相似文献   

7.
A field study was conducted at Beresford, SD, to examine how residual fertilizer phosphorus (P) bands influenced the distribution of Bray-1 extractable P in the soil profile and maize (Zea mays L.) shoot growth and P uptake in a ridge-till system. Liquid ammonium polyphosphate (10-34-0) was injected each fall for three consecutive years in either one or two concentrated subsurface bands in a 5 × 5 cm configuration with respect to the planted seed at rates to provide either 0, 10, 20, or 40 kg P/ha. Soil samples were removed once in the spring before planting with a rectangular block sampler along a 30 cm transect perpendicular to the ridge row to a depth of 15 cm after the third year of the P application. The large sample was separated into eight 7.5 × 7.5 cm × 7.5 cm block sections. Soil was analyzed for Bray-1-extractable orthophosphate-P in each of the sample blocks, composited for increasingly greater soil volumes, and compared with shoot growth and P uptake at the sixth and twelfth leaf and silking stage of growth. Applied-P rate had a strong effect on Bray-1-P levels, increasing them from 7.5 to 195.1 mg P/kg as P rate increased from 0 to 40 kg P/ha. The locations of the previously applied P bands were highly variable in the sampling profile. Coefficients of variation (c.v.) for Bray-1-P levels varied from 1.9 to 141.4 for sampling-block locations and increased as P rate increased. This result indicated that, within treatment replication, there was little consistency with fertilizer P-band placement with respect to the planted seed, and the variability increased with higher P applications. Applied-P rate influenced shoot dry weight, shoot P concentration, and shoot P uptake in the sixth leaf and twelfth leaf growth stages only. The band number had no influence on these parameters. When increasingly larger volumes were considered to improve the accuracy of sampling position with the predictability of the Bray-1 P levels and shoot parameters, the smallest soil volume and sampling position close to the planted seed was as accurate a predictor of shoot parameter responses as the Bray-1 P levels derived from soil composites of larger sampling volumes.  相似文献   

8.
To investigate a proper way to use animal manure as a fertilizer, simulated leaching experiments with soil columns (40 cm) and field experiments were both conducted. Concretely, biological organic fertilizer (BOF), ordinary organic fertilizer (OF), and swine manure (SM) were utilized, with chemical fertilizer (CF) and no phosphorus (NOP) as controls. The mobility of phosphorus and the amount of organic matter (OM) retention in soil were compared. Total phosphorus in the leachate was SM>BOF>OF (simulated) and SM>OF>BOF (field), and the content of Olsen-P in 0 to 20-cm depth of the soil was CF>SM>OF>BOF>NOP (simulated) and CF>BOF>OF>SM = NOP (field), which was caused by the absorption of vegetables in the latter. Moreover, OM retention of BOF treatment was significantly higher than other treatments in 0 to 20-cm depth of soil with vegetable planting. Consequently, it’s not advised to directly apply SM into the soil, while BOF and OF are the better way.  相似文献   

9.
In the Mediterranean region, much emphasis is placed on the role of fertilizers in enhancing crop production to achieve food security. Given the complex nature of phosphorus (P) reactions in soils, considerable research has dealt with fertilizer aspects related to efficient P use, but comparatively less emphasis has been given to plant variation with respect to P efficiency. In this study, selection and adaptation of P‐efficient corn genotypes was seen as one possible approach to enhancing P efficiency. Thus, a greenhouse experiment with 10 corn genotypes (traditional to modern), five P application rates (0–200 mg kg?1), and four field trials with three genotypes for 2 years were carried out on various calcareous soils (Vertic Torrifluvent, Vertic Calciorthid, Entic Chromoxerert, and Typic Xerofluvent). Measurements were made of root characteristics. Treatments in the field trials were five P application rates as main plots (0–68 P ha?1) and three corn genotypes as subplots. Genotypes were selected for the field trials from the greenhouse experiment as “efficient‐responsive,” “efficient‐nonresponsive,” and “inefficient‐responsive.” Dry‐matter (DM) yield and plant P uptake by plants increased with P application rates in the greenhouse experiment. Root length and mass were considerably increased by increasing P levels. Genotypes were classified for P efficiency. The studies indicated that because corn genotypes respond to P‐fertilizer application differently, this trait could be utilized to exploit native and applied P more efficiently, especially at low levels of available P and when P‐ fertilizer use is limited. This differential response derives from morphological, physiological, and genetic variability among the genotypes. Although genotypic efficiency is important for fertilizer management, the contribution of the efficiency is not a substitute for fertilizers, especially if high yields are required. Nevertheless, breeding for P‐use efficiency should be a component of any program to improve crop yield potential.  相似文献   

10.
山东省三大土类的有机磷含量平均为61.59mg kg-1,约占全磷含量的12.37%,其中潮土的有机磷含量极显著高于褐土和棕壤。三大土类土壤不同活性有机磷中,以中稳性活性有机磷(MLOP)为主,平均占有机磷总量的76.37%,3大土类间MLOP、HROP差异极显著,MROP、LOP差异显著;4种不同活性有机磷以活性有机磷(LOP)的有效性最高,是反映土壤磷素有效性的主要指标之一,与土壤肥力密切相关。通过3大土类两个产量水平的有机磷与解磷微生物的数量、强度和各种酶的活性的相关性分析,探讨了土壤有机磷通过土壤微生物和磷酸化酶的生物活性进行转化的机制,为3大土类和两个产量水平的土壤培肥提供了理论依据。  相似文献   

11.
ABSTRACT

The efficient use of phosphorus (P) fertilizers is very important in South Florida so that the environmental impact is minimal while meeting crop demand. To ensure that this is accomplished, an updated soil test P calibration is needed for sugarcane (Saccharum spp.) grown on Florida mineral soils, which accounts for almost 30% of the total sugarcane planted in the state. An outdoor pot experiment was conducted with the objective of evaluating four soil extractants for potential use in soil test P calibrations. Sugarcane cultivar CL 88–4730 was grown in 26L pots in a randomized complete block design with four replications of four P fertilizer rates (0, 38, 76, and 152 mg P L?1 soil) and four soil series (2 Spodosols, 1 Entisol, and 1 Alfisol). Sugarcane biomass was significantly increased with P fertilizer application and extractable soil P significantly increased with increasing P fertilizer rate. Strongest relationships of extractable soil P with relative fresh weight yield were determined with the water, acetic acid, and ammonium acetate extractants. All extractants tested, including Mehlich 3, had significant relationships with relative yield and leaf P concentration and so all these extractants should be considered in further field calibration studies with sugarcane on Florida mineral soils.

Abbreviations: EAA: Everglades Agricultural Area; EREC: Everglades Research and Education Center; OM: organic matter; TSP: Triple superphosphate  相似文献   

12.
Abstract

Nitrate leaching frequently is attributed to the excessive application of mineral nitrogen fertilizers and also to the organic matter incorporated in the soil. A lysimeter experiment was conducted in a greenhouse to evaluate nitrate leaching and pepper productivity in an organically fertilized substrate (prepared by application of 4 kg · m?2 horse manure and subsequent solarization) to which three different doses of mineral fertilizers were added at 0 (T1), 157 (T2), and 313 (T3) kg N · ha?1. The results confirmed the high contribution of organic matter to nitrate leaching, although nitrate losses in T2 and T3 were around 33% and 100% greater than in T1. Furthermore the application of mineral fertilizers (T2 and T3) combined with organic manure led to a decrease in pepper fruit productivity. The use of porous ceramic water samplers for measuring fertilizer leaching is questioned. The results also point to the need for a revaluation of irrigation and N fertilization procedures when organic manure is used in order to improve pepper yield and reduce the contamination of ground water by nitrates.  相似文献   

13.
不同磷肥用量对绿芦笋产量及营养品质的影响   总被引:1,自引:0,他引:1  
2008年3~7月在西辽河平原的内蒙古民族大学实验农场,以4年生芦笋阿波罗(Asparagus officinalis L.cv.Apollo)为试材,研究了不同磷肥用量对绿芦笋产量及营养品质的影响。结果表明,施磷量在0~90 kg hm-2的范围内,绿芦笋产量随施磷量的增加呈先升高后略有降低的变化趋势,单支重和支数均有不同程度的增加。随着磷肥用量的增加,叶绿素a、叶绿素b的含量增加,而类胡萝卜素的含量变化不大;采笋后期叶绿素a、叶绿素b、类胡萝卜素含量均明显地高于采笋前期和中期。可溶性糖、粗蛋白和可溶性蛋白含量总体上随着施磷量的增加而增加;矿质元素含量在一定施磷水平下较高,高量施磷和不施磷处理含量均较低。在试验条件下,施磷量在72 kghm-2下,具有较高的产量和较好的营养品质。  相似文献   

14.
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   

15.
Abstract

Accurate measurement and characterization of phosphate rock dissolution are important for a better understanding of phosphorus (P) availability in soils. An incubation study was carried out on two New Zealand topsoils (0–15 cm; high P buffering capacity Craigieburn and low P buffering capacity Templeton) amended with North Carolina phosphate rock (NCPR) and water‐soluble phosphate (WSP) at 218 mg P kg?1 (equivalent to 60 kg P ha?1). Isotopic exchange kinetics was carried out after 12 h and 28 days of incubation to characterize P availability. This study showed that sensitivity of capacity factors (r1/R, n) to explain changes in E1min values was affected by the P buffering capacity of the soils. The recovery of applied P in the E pool (RecinE%) with extended incubation time was similar from the NCPR and WSP treatments (3.1–3.3%) in the Craigieburn soil compared with the Templeton soil in which RecinE% values were greater in WSP (9%) than NCPR (1.3%) treatment. The higher values of P derived from the applied P fertilizers in the E pool (PdffinE%>80%) suggested that the NCPR application in both soils would be efficient for increasing P availability to plants.  相似文献   

16.
Prediction of accumulation of available phosphorus (P) in paddy soils is crucial for the best management of P fertilizers. Based on the long-term double-rice rotation systems, a predictive model for accumulation rates of Olsen P in paddy soils with chemical fertilization was developed. In paddy soils with more than 40 kg applied P ha?1, the accumulation of Olsen P in the soils could occur. With the target rice yield of 10 tons ha?1 per year, the increases in Olsen P in paddy soils were estimated by the model as 0.7, 2.2, and 3.8 mg kg?1 when P application rates are 40, 60, and 80 kg P ha?1, respectively. The accumulation rate of Olsen P was relatively high in paddy soils. The predictive model can be used to predict accurately the concentrations of Olsen P in paddy soils based on initial Olsen P, P application rate, and crop yield and to optimize P fertilization for rice crop production and environmental protection.  相似文献   

17.
不同硫酸铝用量对苏打盐碱土磷素形态及吸附特性的影响   总被引:2,自引:1,他引:2  
通过室内模拟盆栽改良试验,研究了硫酸铝的改良效果及施用后对土壤中磷素营养状况的影响。硫酸铝配施磷肥和氮肥对小麦的出苗和生长起着明显促进作用。无机磷分级及相关分析结果表明,施加不同用量的硫酸铝后,各级无机磷平均含量的大小顺序为Ca2-P>Ca8-P>Al-P>O-P>Fe-P>Ca10-P,其中,Ca8-P和O-P是Ca2-P的有效补充。磷的吸附实验表明,各处理土壤磷的等温吸附曲线与Langmuir方程的吻合程度最好,其相关程度达极显著水平。根据简单Langmuir方程,将C/x/m对C作图,得到的是具有一个折点的直线,表明随着磷平衡浓度的不同,土壤对磷的吸附存在着两个不同能量水平的吸附点位。磷的解吸结果表明,在磷平衡浓度较低的条件下,土壤与磷的结合能力较强,大多以固定态磷的形式被吸附,并且,解吸也较困难;随着磷平衡浓度的增加,可交换磷所占的比例增加,有较多的磷可被解吸下来。  相似文献   

18.
Crop species and their varieties vary in phosphorus (P) requirements for optimum production and response to P application. As crop recovery of added P often ranges from 10 to 40%, the rest accumulates in soil and may create potential for P leaching, depending upon the soil characteristics, duration of P applications, and cropping systems. Accumulation and distribution of Olsen P (plant-available labile P), total inorganic P, and total organic P were investigated in soil profiles of three field experiments differing in rate (9–44 kg P ha–1), frequency (applied once or twice annually), and duration (4–34 years) of fertilizer P applications, crop rotations, soil characteristics, and irrigation pattern (upland irrigated and flooded-rice crop) in a subtropical region. Profile samples were collected from soil depths of 0–15, 15–30, 30–60, 60–90, 90–120, and 120–150 cm of different treatments in these experiments and analyzed for different forms of P and soil characteristics. The results revealed that (i) annual applications of fertilizer P either to one crop (alternative-applied P) or to both crops (cumulative) led to the accumulation of residual fertilizer P in the form of Olsen P, varying from 44 to 148 kg P ha–1, and the magnitude of accumulation was proportional to applied fertilizer P rate, frequency, and duration; (ii) majority of residual fertilizer P accumulated as inorganic P (74–89%) followed by organic P (11–26%) and Olsen P (9–19%), illustrating that the inorganic P pool is a major sink for fertilizer P; (iii) application of fertilizer nitrogen (N) and potassium (K) alone or in combination with fertilizer P did not affect residual fertilizer P accumulation in soil profile; (iv) incorporation of farmyard manure enhanced the P enrichment of soil profile; (v) irrigation pattern, soil pH (7.1–7.7), and calcium carbonate (CaCO3) (trace–0.33%) did not influence P movement to deeper soil layers; silt, clay, and soil organic C (SOC) showed strong relationships with Olsen P (r = 0.827, 0.938, and 0.464, P < 0.01) and enhanced the retention of labile P in the plow layer; and (vi) only 6–29% total residual P moved beyond 30 cm deep in fine-textured soils under 22-year rice (Oryza sativa L.)–wheat (Triticum aestivum L.) and 34-year maize (Zea maize L.)–wheat rotations, whereas 41, 27, 20, 9, and 3% were located in soil layers 0–30, 30–60, 60–90, 90–120, and 120–150 cm deep, respectively, in coarse-textured soil profile under 4-year peanut (Arachis hypogaea L.)–sunflower (Helianthus annuus L.) field. These findings confirmed that interplay between the fertilizer P management (alternative vis-à-vis cumulative P application and optimal vis-à-vis excessive rates of fertilizer P in different crop rotations), amount of labile P accumulated in soil profile, and soil characteristics (silt, clay, and SOC) largely controlled the downward movement and resultant potential for P leaching in subtropical irrigated soils.  相似文献   

19.
This study evaluated the effects of phosphorus (P) fertilizer levels on inorganic P fractions. Wheat cultivars (Azadi and Marvdasht) were grown in the soils amended with the four rates of P fertilizer levels (no fertilizer, 10, 15, and 25 mg available P kg?1 soil). Soils were sampled from rhizosphere and non-rhizosphere areas after 6 weeks. The mean of all P fractions was significantly different in various P fertilizer levels. The smallest and the largest amounts of all P fractions were observed in the soil with no P and in 25 mg kg?1 soil P level, respectively. The Azadi cultivar, as P-efficient, showed the smallest increase in soil P fractions with increasing soil P levels. The means of all P fractions except Al-phosphates (Al-P) were significantly higher in non-rhizosphere soil. There were differences between these cultivars associated with the more inaccessible fractions at the 15 mg P kg?1 soil level.  相似文献   

20.
Liming or adding organic matter may improve productivity of soils receiving phosphorus (P) fertilizers. This study assessed the effectiveness of amendment of acidic soil with limestone and organic matter on growth of tomato (Lycopersicon esculentum Mill.), corn (Zea mays L.), and cucumber (Cucumis sativus L.) with different P fertilizers. These crops were grown in a greenhouse to evaluate superphosphate, bone meal, and rock phosphate as fertilizers and calcitic limestone and peat moss as amendments. Superphosphate was the superior P source to sustain crop growth, limit deficiency symptoms, and enhance P accumulation. Bone meal was less effective than superphosphate but exceeded rock phosphate in these capacities. Rock phosphate was better than adding no P fertilizer. The amendments of limestone or organic matter singly or together had little effect on growth, appearance, or P accumulation. The availability of P in the fertilizers governed the growth responses of the plants.  相似文献   

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