Steel Slag as an Iron Fertilizer for Corn Growth and Soil Improvement in a Pot Experiment

The feasibility of steel slag used as an iron fertilizer was studied in a pot experiment with corn. Slag alone or acidified slag was added to two Fe-deficient calcareous soils at different rates. Results showed that moderate rates (10 and 20 g kg-1) of slag or acidified slag substantially increased corn dry matter yield and Fe uptake. Application of steel slag increased the residual concentration of ammonium bicarbonate-diethylenetriamine pentaacetic acid (AB-DTPA) extractable Fe in the soils. The increase of extractable Fe was usually proportional to the application rate, and enhanced by the acidification of slag. Steel slag appeared to be a promising and inexpensive source of Fe to alleviate crop Fe chlorosis in Fe-deficient calcareous soils.

Crop yields and soil organic carbon dynamics in a long-term fertilization experiment in an extremely arid region of northern Xinjiang, China

A long-term fertilization experiment was set up in northern Xinjiang, China to evaluate the dynamics of crop production and soil organic carbon （SOC） from 1990 to 2012 with seven fertilization treatments. The seven treatments included an unfertilized control （CK） and six different combinations of phosphorus （P）, potassium （K）, nitrogen （N）, straw （S） and animal manure （M）. The balanced fertilization treatments had significantly （P〈0.05） higher average yields than the unbalanced ones. The treatment with 2/3 N from potassium sulfate （NPK） and 1/3 N from farmyard manure （NPKM） had a higher average yield than the other treatments. The average yields （over the 23 years） in the treatments of NPK, and urea, calcium superphosphate （NP） did not differ significantly （P〉0.05） but were higher than that in the treatment with urea and potassium sulfate （NK; P〈0.05）. The results also show that the highest increases in SOC （P〈0.05） occurred in NPKM with a potential increase of 1.2 t C/（hm2.a）. The increase in SOC was only 0.31, 0.30 and 0.12 t C/（hm2.a） for NPKS （9/10 N from NPK and 1/10 N from straw）, NPK and NP, respectively; and the SOC in the NP, NK and CK treatments were approaching equilibrium and so did not rise or fall significantly over the 23-year experiment. A complete NPK plus manure fertilization program is recommended for this extremely arid region to maximize both yields and carbon sequestration.

Approach for improving precision of regression analysis of single-replication fertilization experiments in rice

The field experiment designs with single replication were frequently used for factorial experiments in which the numbers of field plots were limited, but the experimental error was difficult to be estimated. To study a new statistical method for improving precision of regression analysis of such experiments in rice, 84 fertilizer experiments were conducted in 15 provinces of China, including Zhejiang, Jiangsu, Anhui, Hunan, Sichuan, Heilongjiang, etc. Three factors with 14 treatments (N: 0—225kg/ha, P: 0 —112. 5kg/ha, K: 0—150kg/ha) and two replications were employed using approaching optimun design. There were 2352 (84×14×2=2352) Yield deviations (d) between the individual treatment yields and its arithmetic mean. The results indicated that:

Studies on the Fertilization Effect and Optimal Fertilizing Amount of Brazil Banana Based on "3414" Field Trials

Fertilizer effect model such as ternary quadratic, unary quadratic, straight line and platform model was respectively used to analyze the two-year ＂3414＂ test data collected from banana garden in Fushan Town of Hainan Province. The results showed that the optimal fertilizing amount of ternary quadratic model simulation was0.374 kg/plant of N, 0.289 kg/plant of P2O5 and 0.891 kg/plant of K2 O. According to the yield trend characteristic, the optimal fertilizing amount of unary quadratic model was 0.400kg/plant of N, 0.214 kg/plant of P2O5 and 0.901kg/plant of K2 O. Thus it can be seen that only partial indices of the optimal fertilizing amount of ternary quadratic model simulation were higher than that of unary quadratic model. Considering the results, the optimal fertilizing amount of Brazil banana was 0.374-0.400kg/plant of N, 0.214-0.289 kg/plant of P2O5 and 0.891-0.901 kg/plant of K2 O.

基于“3414”试验模型的四川盆地中部水稻氮磷钾肥效应研究

本研究采用“3414”肥料效应田间试验,旨在确定四川盆地中部资中县水稻的最佳施肥量,并构建高产施肥模型。通过设置氮、磷、钾3因素,每个因素4个水平,共14个处理,每个处理重复3次。结果表明:建立的三元二次肥料效应回归方程的相关系数(R^(2))为0.976。纯氮施用量为215.28 kg/hm^(2),五氧化二磷施用量为101.40 kg/hm^(2),氧化钾施用量为104.14 kg/hm^(2),水稻最大产量为7923.56 kg/hm^(2);纯氮最佳施用量为196.83 kg/hm^(2),五氧化二磷施用量为74.81 kg/hm^(2),氧化钾施用量为102.90 kg/hm^(2),水稻最佳产量为7867.96 kg/hm^(2)。建立的肥料效应模型可在四川盆地中部类似水稻产区推广,用于水稻生产上对施肥量的预测。

Effects of “3414” Fertilization Effect Test on the Yield and Economic Benefit of Sagittaria sagittifolia

[Objective] To screen the optimal fertilizer formula, and to lay foundation for the research on special fertilizer for Sagittaria sagittifolia production. [Method] Based on the ＂3414＂ fertilization design, the yield of S. sagittifolia in each treatment was determined, and the effects of N, P and K treatments on the yield and eco- nomic benefit of S. sagittifolia were investigated, obtaining the optimal fertilizer appli- cation ratio. [Result] N, P and K had relatively good effects on the yield of S. sagittifolia. Treatment of N2P2K3 showed the optimal fertilizer application ratio, with the yield of 18 397.80 kg/hm2, yield increasing rate of 104.77%, and net income in- crease of 80 317.35 Yuan/hm2. N fertilizer had the greatest impacts on the yield of S. sagittifolia, followed with K fertilizer; while P fertilizer showed the poorest impacts. [Conclusion] To achieve the highest yield of S. sagittifolia, the fertilizer application was as follows： N of 446.70 kg/hm2, P20 of 568.10 kg/hm2, K2O of 534.90 kg/hm2, when the highest yield was 18 612.75 kg/hm2. Fertilizer application for the optimal economic benefit was N of 420.60 kg/hm2, P2O5 of 70.50 kg/hm2, K2O of 492.15 kg/hm2, when the optimal yield was 18 579.00 kg/hm2.

Effects of Long-Term Combined Application of Organic and Mineral Fertilizers on Microbial Biomass,Soil Enzyme Activities and Soil Fertility

Soil health is important for the sustainable development of terrestrial ecosystem. In this paper, we studied the relationship between soil quality and soil microbial properties such as soil microbial biomass and soil enzyme activities in order to illustrate the function of soil microbial properties as bio-indicators of soil health. In this study, microbial biomass C and N contents （Cmic ＆ Nmic）, soil enzyme activities, and soil fertility with different fertilizer regimes were carried out based on a 15-year long-term fertilizer experiment in Drab Fluvo-aquic soil in Changping County, Beijing, China. At this site, 7 different treatments were established in 1991. They were in a wheat-maize rotation receiving either no fertilizer （CK）, mineral fertilizers （NPK）, mineral fertilizers with wheat straw incorporated （NPKW）, mineral fertilizers with incremental wheat straw incorporated （NPKW＋）, mineral fertilizers plus swine manure （NPKM）, mineral fertilizers plus incremental swine manure （NPKM＋） or mineral fertilizers with maize straw incorporated （NPKS）. In different fertilization treatments Cmic changed from 96.49 to 500.12 mg kg^-1, and Nmic changed from 35.89 to 101.82 mg kg^-1. Compared with CK, the other treatments increased Cmic ＆ Nmic, Cmic/Corg （organic C） ratios, Cmic/Nmic, urease activity, soil organic matter （SOM）, soil total nitrogen （STN）, and soil total phosphorus （STP）. All these properties in treatment with fertilizers input NPKM＋ were the highest. Meantime, long-term combined application of mineral fertilizers with organic manure or crop straw could significantly decrease the soil pH in Fluvo-aquic soil （the pH around 8.00 in this experimental soil）. Some of soil microbial properties （Cmic/Nmic, urease activity） were positively correlated with soil nutrients. Cmic/Nmic was significantly correlated with SOM and STN contents. The correlation between catalase activity and soil nutrients was not significant. In addition, except of catalase activity, the soil pH in this experiment was negatively correlated with soil microbial properties. In conclusion, soil microbial properties reflect changes of soil quality and thus can be used as bio-indicators of soil health.

Changes of Organic Matter, N, P and K Content of Soils in Red Soil Areas Under Long-Term Experiment

The content of organic matter （OM）, nitrogen （N）, phosphorus （P）, and potassium （K） in the three selected soils, including Calcaric Purpli-Orthic Primosols （purple sand-shale parent material）, Dystric Turbi-Anthric Primosols （quaternary red clay parent material） and Typic Udi-Sandic Primosols （granite parent material） were studied under a long-term experiment by using crop straw and inorganic fertilizers at the Hunan Red Soil Experiment Station of Chinese Academy of Agricultural Sciences. The results showed that the contents of OM, N, P and K in the three selected soils increased after 23 years application of crop straw and inorganic fertilizers, but the contents increased much less when crop straw or inorganic fertilizers was applied alone. The nutrient contents in the three soils developed from granite changed more remarkably than those in the soil derived from quaternary red clay and purple sand-shale. It was also found that the contents of OM, N, and P increased slightly in the treatments without applying fertilizers or returning the crop straw to the root bed. Combined application of inorganic fertilizers and crop straw could remarkably increase the contents of OM, alkalihydrolyzable N and available K, the positive correlation between application of organic fertilizers and increase of OM in soil did not always happened, it provided evidence for the relation between appropriate C/N ratio and accumulation of OM in soil. The increase of nutrient content was influenced by the soil properties. By comparing the contents of nutrient in 0-20 cm depth in the three different soils, it was concluded that the most increases of OM, alkali-hydrolyzable N, and available P were observed in Typic Udi-Sandic Primosols with the average increase by 3.03, 27.38, and 21.73 mg kg^-1, respectively. The available K increased in Dystric Turbi-Anthric Primosols with the average increase by 25.82 mg kg^-1, while it decreased in Calcaric Purpli-Orthic Primosols and Typic Udi-Sandic Primosols. It was concluded that the application of inorganic fertilizer and crop straw was important to improve the soil fertility for all of three selected soils. The straw return to the field had played a significant role for enhancement of the soil quality in the study areas. The application of inorganic fertilizer combined with the straw return to the fields could remarkably improve the soil fertility.

Study on structural characteristics of pillared clay modified phosphate fertilizers and its increase efficiency mechanism

Three types of new high-efficiency phosphate fertilizers were made when pillared clays at certain proportions were added into ground phosphate rock. Chemical analyses showed that their soluble phosphorus content decreased more than that of superphosphate. Pot experiment showed that, under equal weights, the new fertilizers increased their efficiency by a large margin over that of superphosphate. Researches on their structures by means of XRD, IR and EPR spectrum revealed that their crystal structures changed considerably, improving their activity and preventing the fixation of available phosphorus in the soil, and consequently, greatly improved the bioavailability and became the main cause of the increase of biomass.

Preparation and efficacy evaluation of Paenibacillus polymyxa KM2501-1 microbial organic fertilizer against root-knot nematodes

Root-knot nematodes(RKNs) cause huge yield losses to agricultural crops worldwide. Meanwhile, livestock manure is often improperly managed by farmers, which leads to serious environmental pollution. To resolve these two problems, this study developed a procedure for the conversion of chicken manure to organic fertilizer by larvae of Hermetia illucens L. and Bacillus subtilis BSF-CL. Chicken manure organic fertilizer was then mixed thoroughly with Paenibacillus polymyxa KM2501-1 to a final concentration of 1.5×10^(8)CFU g^(-1). The efficacy of KM2501-1 microbial organic fertilizer in controlling root-knot nematodes was evaluated in pot and field experiments. In pot experiments, applying KM2501-1 microbial organic fertilizer either as a base fertilizer or as a fumigant at the dose of 40 g/pot suppressed root-knot disease by 61.76 and 69.05% compared to the corresponding control treatments, respectively. When applied as a fumigant at the dose of 1 kg m;in field experiments, KM2501-1 microbial organic fertilizer enhanced the growth of tomato plants, suppressed root-knot disease by 49.97%, and reduced second stage juveniles of RKN in soil by 88.68%. KM2501-1 microbial organic fertilizer controlled RKNs better than commercial bio-organic fertilizer in both pot and field experiments. These results demonstrate that this co-conversion process efficiently transforms chicken manure into high value-added larvae biomass and KM2501-1 microbial organic fertilizer with potential application as a novel nematode control agent.

基于3414试验设计的云南雪茄烟叶生产施肥技术研究

为明确云南省瑞丽雪茄烟区土壤合理施肥方案,采用“3414”肥料试验设计,通过熵权法和回归分析,计算了各处理对应的烟株农艺性状综合得分,探究了N、P、K对雪茄烟株长势和烟叶产量的影响,筛选出最佳施肥方案。结果表明:(1)株高对雪茄烟株农艺性状的得分所占权重最大,处理6(N_(2)P_(2)K_(2))对应的得分最高。(2)在一定范围内增加N、P、K的施用量,对雪茄烟的产量有积极作用,然而随着施肥量的增加产量又有所下降。(3)构建了N、P、K施用量对雪茄烟产量的二元二次和三元二次回归模型,最佳施肥方案为N施用量在118.7~126.9 kg/hm^(2)之间,P_(2)O_(5)施用量在75.7~81.4 kg/hm^(2)之间,K_(2)O施用量在342.1~366.5 kg/hm^(2)之间,目标产量在1816.3~1812.5 kg/hm^(2)之间。

基于“3414”试验的切花芍药氮磷钾推荐施肥量研究

针对切花芍药生长过程中盲目施肥的现状,以二年生芍药‘向天歌’为研究对象,采用“3414”试验施肥方案,结合隶属函数法,研究氮、磷、钾肥不同用量对切花芍药生长的影响,探讨切花芍药生产适宜的肥料用量。结果表明:不同施肥处理对芍药株高、茎粗、蕾径、分株数和切花数影响显著(P<0.05);氮、磷缺素区的综合隶属函数值小于无肥区,缺钾区大于无肥区,对芍药生长的影响为氮>磷>钾;N2P2K1处理的综合隶属函数值最大,为0.61,芍药植株生长最好;对各处理的综合隶属函数值和施肥量进行肥料效应函数拟合分析,一元二次、二元二次肥料效应函数方程拟合相关性均达显著水平,三元二次肥料效应方程为非典型模型,采用频率分析法计算肥料推荐量。综合分析各肥料效应函数方程的推荐用量及相应的综合隶属函数值,本试验切花芍药推荐施肥量为N 212.7 kg/hm^(2)、P_(2)O_(5)46.2 kg/hm^(2)、K_(2)O 49.9 kg/hm^(2),施肥配比为1∶0.21∶0.23,可用于本试验区切花芍药生产的施肥参考。

Effects of Different N, P and K Fertilizer Levels on Growing Characters and Yield of Corn

[Objective] To provide scientific guidance for corn production in Suijiang County of Yunnan Province, explore the best recommended fertilization of corn, and provide a scientific basis for formulating the formula fertilization of corn in Suijiang County. [Method] Through carrying out ＂3414＂ corn field fertilizer efficiency experiment in Suijiang County, with the help of ＂3414＂ field experiment design and data analysis management system＂ software, the ternary quadratic and one-variable quadratic fertilizer efficiency equations on corn yield were analyzed. [Result] The optimum fertilization scheme for corn in the region was as follows： when pure N, pure P2O5 and K2O were respectively 244.38, 58.75 and 107.38 kg/hm^2, the the obtained best yield of corn was 6 975.60 kg/hm^2, and the maximum benefit was 16 888.58RMB/hm^2. [Conclusion] The reasonable formula of N, P and K fertilizers can not only improve the yield of corn, but also increase economic benefit, having certain reference significance to the development of formula fertilization of corn in Suijiang County.

甘南高寒阴湿区宽幅匀播青稞“3414”肥效试验

为了将宽幅匀播技术与“3414”肥效试验相结合,应用于甘南高寒阴湿区青稞种植与示范推广中,推动该地区青稞种植产业发展。采用“3414”最优回归设计,以青稞甘青9号为指示品种,在宽幅匀播条件下研究了“3414”肥效试验对青稞生长及产量的影响,并建立了青稞产量与氮、磷、钾施量之间的肥效回归方程,以提高肥效,促进甘南高寒阴湿区青稞生产优质高产。结果表明,宽幅匀播条件下,甘青9号最佳产量为6640.32kg/hm^(2)时,施肥量为N36.34kg/hm^(2)、P_(2)O_(5)55.86kg/hm^(2)、K_(2)O7.09kg/hm^(2);最大产量为6834.09kg/hm^(2)时,施肥量为N80.66 kg/hm^(2)P_(2)O_(5)62.31kg/hm^(2)、K_(2)O16.58kg/hm。肥效回归方程中施肥量与青稞产量拟合度显著,可应用于大田生产。

Preparation and Effectiveness of Slow-release Polymeric Fertilizer Containing Multiple Nutrients Special for Maize

Slow-release polymeric fertilizer containing multiple nutrients was synthesized through condensation polymerization from raw materials of homemade low-molecular urea-formaldehyde and the compounds of potassium dihydrogen phosphate and phosphoric acid. Adjustment of the proportion of raw materials makes the ingredients of the fertilizer are N:P_2O_5:K_2O =1:0.75:0.13, which satisfy the nutritional requirement for maize growth. Field-experiment results prove that the yield of maize increases by 16.56% when using the polymeric fertilizer special for maize alone, by 56.51% when applying the polymeric fertilizer special for maize plus farmyard manure, and by 49.11% when applying the SV fertilizer special for maize plus manure.

基于“3414”肥效试验建立BP神经网络寻优的新模型初探

针对上海市崇明滧东地区传统施肥方式不能满足水稻需肥规律的问题,以水稻“3414”肥效试验结果为数据来源,以N、P_(2)O_(5)、K_(2)O施用量为优化目标,建立3-7-1拓扑结构BP神经网络模型,通过遗传算法得到最优产量下的最优施肥配比。预测结果表明:当地较优的施肥配比是N、P_(2)O_(5)、K_(2)O的施用量分别为24.94、0.87、4.27 kg/亩(1亩=667 m^(2)),预计最高产量为531.5 kg/亩。通过验证试验,在较优的施肥配比条件下,水稻的实际产量为548.7 kg/亩,验证了BP神经网络模型预测结果的准确性。

贞丰县下等肥力地小麦“3414”肥料效应试验

[目的]探索贞丰县下等肥力地小麦氮、磷、钾肥最佳施肥配比。[方法]通过小麦“3414”肥料效应田间试验,对不同施肥处理的小麦产量进行分析比较,以确定最佳施肥配比。[结果]施用不同配比的氮、磷、钾肥对小麦的农艺性状和产量有不同的影响,当施肥量为N 390 kg/hm^(2),P_(2)O_(5)750 kg/hm^(2),K_(2)O 124.5 kg/hm^(2)时,小麦的产量最高,为4 971.0 kg/hm^(2),较未施肥区增产2 131.5 kg/hm^(2)。[结论]在与该试验相同肥力条件的下等肥力地种植小麦,推荐最佳施肥量为:N 390 kg/hm^(2),P_(2)O_(5)750 kg/hm^(2),K_(2)O 124.5 kg/hm^(2)。

3414"肥料试验模型拟合的探讨

以UNDP95-98年在河北唐山进行的27个"3414"冬小麦试验为例,研究了三元二次施肥模型与一元施肥模型对"3414"肥料试验结果的拟合情况。结果表明,三元二次施肥模型进行拟合试验成功率仅为56%,而采用一元施肥模型可以对全部试验进行数据处理。在同一试验中,与一元施肥模型相比,采用三元二次施肥模型计算的推荐施肥量偏高;根据一元施肥模型拟合计算分别有15%、44%、67%的点不需要施用N、P、K肥,而采用三元二次施肥模型则无法获得这一信息。因此,在"3414"试验中,一元施肥模型是三元二次施肥模型拟合的一种很好补充和优化手段。

应用“3414”肥料试验模型求解春玉米施肥参数的研究

利用现代肥料二次回归"3414"设计,对春玉米施肥参数进行了研究。结果表明:通过三元二次肥料效应函数获得的最高产量在各类型函数中最低,投入的肥料价值也最低,获得的产投比较高;通过一元二次肥料效应函数获得的最高产量最高,其中K处理一元二次肥料效应方程获得的最高产量和产投比最高。各类型函数所获得的最佳经济产量表现为:一元函数>二元函数>三元函数,但三元二次肥料效应函数所获得的产投比远远高于其他函数,可用于推荐施肥。通过三元二次肥料效应函数获得的春玉米推荐施肥指标为:N162.8kg/hm2,P2O5112.7kg/hm2,K2O149.7kg/hm2,需要投入的肥料成本为1776元/hm2,可获得最佳经济产量13241kg/hm2,产投比高达7.45。

免耕水稻在“3414”试验方案中氮磷钾配施的肥料效应研究

在免耕抛秧种植模式下进行"3414"肥料效应试验,通过建立氮、磷、钾施肥量与产量的回归模型,探索当地水稻的最佳施肥量。结果表明,氮磷钾施用量均为中等水平时,产量和经济效益达到最佳;各类型函数所获得的最佳经济产量表现为一元函数>二元函数>三元函数。结合一元、二元、三元肥料效应函数及实际生产而获得的推荐施肥指标:最高产量施肥量为每公顷施N 197.70 kg,P2O573.05 kg,K2O 180.00 kg;最佳产量施肥量为每公顷施N 194.10 kg,P2O5 65.55 kg,K2O 170.10 kg。