有机土配方与生姜产量品质的关系

采用二次饱和D-最优设计,研究了有机土配方对生姜生长的影响,建立了以基质玉米秸秆和速效氮磷钾含量为变量因子,生姜产量和品质分别为目标函数的二元二次数学模型。模型解析表明,玉米秸秆对生姜产量和品质的影响大于速效氮磷钾。在低水平条件下,生姜产量和品质均随着栽培基质中玉米秸秆及速效氮磷钾含量的增加而增加,当氮磷钾含量分别为2588和1468 mg/kg时,生姜产量和品质达到最高值,分别为75.98 t/hm2和88.17;当玉米秸秆含量为41.5%时,生姜产量最高,为82.50 t/hm2,之后,继续增加玉米秸杆和速效氮磷钾含量,则产量逐渐降低;但生姜品质则以玉米秸秆含量为50.0%时最优,为98.02。通过计算机模拟得出,本试验条件下,生姜优质高产有机土配方为:玉米秸秆含量35.6%~46.0%、速效氮磷钾的含量2238～3180 mg/kg。     

On-Site Assessment of Extractable Soil Nutrients after Long-Term Biosolid Applications to Perennial Forage

The objective of this study was to evaluate soil nutrient loading and depth distributions of extractable nitrogen (N), phosphorus (P), and potassium (K) after long-term, continuous annual surface applications of anaerobically digested class B biosolids at a municipal recycling facility in central Texas. Commercial forage production fields of coastal bermudagrass (Cynodon dactylon L.) were surface applied at 0, 20, 40, or 60 Mg dry biosolids ha^?1 y^?1 for 8 years. Application duration was evaluated in fields treated with 20 Mg dry biosolids ha^?1 y^?1 for 0, 8, or 20 years. Total soil loads of extractable inorganic N and P increased linearly with application rate, but only extractable P increased with duration. Neither total load nor soil distribution of extractable K was affected by biosolid applications. Mineralization of biosolid-derived organic N and P likely contributed to elevated concentrations of nitrate throughout the soil profile (0–110 cm) and orthophosphate in surface soils (0–40 cm).     

Crop Nutrient Status and Nitrogen,Phosphorus, and Potassium Balances Obtained in Field Trials Evaluating Different Fertilizer Recommendation Systems on Various Soils and Crops in Hungary

Based on correlations calculated from the database of long-term fertilization experiments carried out in Hungary between 1960 and 2000, a new, cost-saving, and environmentally friendly fertilizer recommendation system was developed. The aim of the new system is to apply the lowest possible nitrogen (N)–phosphorus (P)–potassium (K) rates required to achieve good yields and maximum income per unit area. The World Phosphorus Institute (IMPHOS) agreed to finance a 3-year program to test various Hungarian fertilizer recommendation systems (the new RISSAC-RIA [Research for Soil Science and Agricultural Chemistry‐Research Institute for Agriculture] system, the Talajer?gazdálkodás integrated soil fertility management system, and the intensive MÉM NAK [Department of Plant Protection and Agricultural Chemistry of the Ministry of Food and Agriculture] system) when applied to three major crops grown on three characteristic Hungarian soils. The first five treatments in the experiment represented a classical deficiency experiment, aimed at checking the correctness of the NPK supply categories determined by the various systems. On all three soils and for all three crops the IMPHOS experiments confirmed the basic principles of the new cost-saving, environmentally friendly fertilizer recommendation system and the correctness of the methods used for calculating fertilizer rates. In this article, diagnostic plant analysis, soil analysis data, and NPK balances obtained in the different recommendations are discussed. In most cases the plant NPK contents of all the recommendations exceeded the lower limits of the good NPK supply category for wheat and barley shoot as well as for corn leaf. Crop NPK contents in Talajer?gazdálkodás and MÉM NAK treatments (with greater recommended NPK doses) were most cases better than in the RISSAC-RIA treatments; however, the better crop NPK status did not result in extra grain yield in the former treatments. Taking into account that similarly high yields were obtained using the RISSAC-RIA system and the Talajer?gazdálkodás integrated system with much smaller NPK doses than those recommended by the intensive MÉM NAK system, it was more advantageous from agronomic, environmental protection, and economic points of view. Differences in PK balances correlated well with the differences in the measured soil ammonium lactate (AL)–PK contents after the third year of the experiment.     

Improving Soil Fertility to Support Grass–Legume Revegetation on Lignite Mine Spoils

The short-term sequential effects of different treatments on soil fertility and revegetation of mine spoils were examined in a lignite mine in northwestern Spain. Experimental plots were established both on old and recent spoils after tillage and treated with compost or nitrogen (N), phosphorus (P), potassium (K), + magnesium limestone before seeding with a grass–legume species mixture. Compost improved plant production and, contrary to NPK, maintained soil N levels and supplied enough P for the establishment and early growth of the vegetation. Severe magnesium (Mg), calcium (Ca), and K limitations in recent spoils were only alleviated by compost + magnesium limestone, allowing the rapid growth and coating of the soil surface. The amendment based on NPK + magnesium limestone improved plant production in the short term but caused proliferation of weeds. Results suggest that revegetation in combination with the appropriate amendments is a key issue for the reclamation of lignite mine spoils.     

蔬菜氮磷钾三元肥效模型的MonteCarlo建模法

应用"3414"设计的田间肥料试验结果,探讨蔬菜氮磷钾三元肥效模型的Monte Carlo建模法。莴苣试验结果表明,采用最小二乘法回归建模,NP、NK二元肥效模型属于非典型式,PK二元和NPK三元肥效模型属于典型式;而改用MonteCarlo建模法,NP、NK和PK二元肥效模型以及NPK三元肥效模型均属于典型式。采用最小二乘法回归建模,不同蔬菜作物建立的34个三元肥效模型的典型式出现机率为41.2%,而Monte Carlo建模法的典型式出现机率为91.2%,提高了2.2倍。Monte Carlo建模法是适当放弃数学上偏差平方和最小的最优性,使待估参数达到专业上最优而数学上较优,从而提高典型肥效模型的出现机率。对莴苣氮钾非典型肥效模型的推荐施肥表明,Monte Carlo法的结果明显优于产量频率分析法。因此,Monte Carlo建模法为建立蔬菜多元肥效模型和推荐施肥提供了一种有效方法。     

不同栽培技术对水稻产量及径流NPK流失的影响

在大田试验条件下,以水稻品种苏101为供试材料,设置超高产生产技术、常规生产技术和减肥生产技术3个处理,研究不同栽培技术对水稻产量及农田径流NPK流失的影响。结果表明:超高产生产技术水稻产量比常规生产技术增加了11.1%,减肥生产技术与常规生产技术产量差异不大;试验年度稻季农田总径流深为3.9×10² mm;稻田地表径流水体总N、总P和K流失量从高到低均依次为超高产生产技术、常规生产技术和减肥生产技术,处理间的差异多达到显著水平;减肥生产技术与常规生产技术稻田地表径流NPK流失率差异不大,但均显著大于超高产生产技术;不同栽培技术条件下水稻N肥的偏生产力从大到小依次为减肥生产技术> 常规生产技术> 超高产生产技术;超高产生产技术在显著提高水稻产量的同时,也增加了稻田地表径流NPK流失量,虽然采取秸秆还田和耕翻措施可使其NPK流失率显著降低,但其N肥偏生产力显著降低,而采取秸秆还田的减肥生产技术,水稻产量与常规生产技术大致相当,且稻田地表径流NPK流失量显著降低,N肥的偏生产力显著增加,因而是一种更为环保型的栽培技术措施。     

油菜叶片衰老与NPK含量变化

定期测定油菜生长后期叶片N，P，K含量结果表明：（1）随着叶片衰老N，K含量下降较快，约有80％以上的N素和90％以上的K素在衰老过程中输向其它器官；（2）P素含量在叶片衰老过程中下降幅度较小，向外输送量约30％，（3）适量施用N肥能延缓叶片N，K养分输出。     

不同氮磷钾配比追肥对幼龄骏枣生长及其产量和品质的影响

采用田间试验方法,连续两年对1~3年树龄的幼龄骏枣开展研究,探讨氮磷钾肥对不同树龄骏枣幼树的生长和结果的影响。结果表明:(1)适量的氮磷钾施肥水平可以促进幼龄骏枣的生长,提高枣果产量和品质,但施用过量将会产生肥害;(2)与本试验土壤肥力相似的土壤中,氮磷钾的适宜配比为3.7∶3.6∶1,即1年生幼龄骏枣的适宜施肥量为N 55 g/株、P2O554 g/株、K2O 15 g/株;2年树龄骏枣N 110 g/株、P2O5108 g/株、K2O 30g/株;3年树龄骏枣N 220 g/株、P2O5216 g/株、K2O 60 g/株。     

Mixed Fertilizer can Improve Fruit Yield and Quality of Field-Grown Tomatoes Irrigated with Saline Water

Growing tomatoes using saline water and in soils with poor nutrient contents is challenging. The objectives of this work were to: (i) examine the yield and quality of tomatoes (Lycopersicon esculentum L.) irrigated with different saline water [electrical conductivity (ECi) = 3, 6 and 9 dS m^?1]; and (ii) study the effect of fertilizer: inorganic, organic, and a mixed of both on tomatoes grown under saline conditions. Fruit weight and quality attributes including size, color, soluble solids, acidity, EC, and pH were measured. Growing tomatoes under 3 and 6 dS m^?1 produced the highest yield, whereas irrigating with 9 dS m^?1 reduced yield. The mixed fertilizer slightly ameliorated the yield reduction caused by salinity. Using organic fertilizer alone produced the lowest fruit yield. Fruit quality was more affected by salinity than fertilizer. The best growing conditions for tomatoes were in plots irrigated with 6 dS m^?1 water under mixed fertilizer treatment.