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1.
采用416-B最优混合设计,以珍珠岩作为保护地基质栽培小白菜.研究NO3^--N、P、K和NH4^ -N对保护地无土栽培小白菜产量和硝酸盐含量的影响。结果表明.氮素是影响小白菜产量和硝酸盐含量的主要因素;磷、钾的单效应作用较氮素小,主要通过对氮的互作效应影响产量和磷酸盐含量;最优的小白菜营养液配方为:NO3^--N、P、K和NH4^ -N的浓度分别为6.98,1.08,6.45和2.76mmol/L。  相似文献   

2.
Leaf litter decomposition is a critical step in nutrient cycling and providing nutrients to plants. Decomposition of dry matter, lignin, ligno-cellulose, cellulose and polyphenols was investigated in relation to nitrogen (N), phosphorus (P) and potassium (K) dynamics in leaf litter of mango, guava and litchi orchards under hot and dry sub-humid climate. Leaf litter of mango and guava decomposed more rapidly than that of litchi with decay constants of 3.22, 1.33 and 0.62 yr-1, respectively. The leaf litter organic substances like polyphenol lost more rapidly followed by cellulose, lignin and ligno-cellulose throughout the period of decomposition. The N was released faster both in mango and guava with decay constant of 4.06 and 2.11 yr-1, respectively. The release of K was faster in mango followed by guava and litchi with decay constant of 4.66, 3.18 and 1.63 yr-1, respectively. The leaf litter decomposition was significantly positively correlated with soil fungal and bacterial biomass, rainfall and air temperature, while the leaf chemistry showed significant negative correlations in all the orchards. The results demonstrated that mango leaf litter was found to be the best followed by guava, and litchi in terms of N, P, and K return in less period of time.  相似文献   

3.
中国作物秸秆养分资源数量估算及其利用状况   总被引:80,自引:16,他引:80  
基于统计数据、农户调研数据以及公开发表的文献资料中的数据,估算了2006年中国作物秸秆及其养分资源数量,并且对其利用状况进行了详细的分析。结果表明,2006年中国作物秸秆资源数量超过7.6亿t,其中,作物秸秆氮、磷(P2O5)、钾(K2O)养分资源数量分别达到776万t、249万t、1 342万t。从作物秸秆去向来看,作物秸秆还田、秸秆饲用、秸秆燃烧以及其他去向所占比例分别为24.3%、29.9%、35.3%和10.5%。从不同利用方式下作物秸秆养分还田情况来看,2006年中国作物秸秆氮、磷(P2O5)、钾(K2O)养分还田量分别达到304.6万t、175.6万t、966.7万t,占秸秆养分资源量的比例分别为39.3%、70.5%和72.0%,这表明秸秆还田比例及其养分还田比例仍然有很大的提升空间。  相似文献   

4.
Several nitrogen (N)‐rate field experiments were carried out in cotton to define dilution curves for critical N concentrations in individual plants (i.e., the minimum N concentration required for maximum growth at any growth stage). Nitrogen application rate had a significant effect on aboveground dry matter, N accumulation, and N concentration. As expected, shoot N concentration in plants decreased during the growing period. These results support the concept of critical N concentration in shoot biomass of single plants as described by Lemaire et al. (2007) and reveal that a dilution curve for critical N concentrations in cotton plants can be described by a power equation. The pattern of critical–N concentration dilution curves was consistent across the two sites. Nitrogen concentration for a given biomass varied greatly with the supply of N. After initial flowering, the N‐nutrition index (NNI) for aboveground biomass of individual plants increased with increasing N rates. Relationships between plant total N uptake and accumulated dry matter in the aboveground biomass can be described by the allometric‐relation equations for each dose of N. Nitrogen‐dilution curves can be used as a tool for diagnosing the status of N in cotton from initial flowering to boll opening. The relationship can also be used in the parameterization and validation of growth models for predicting the N response and/or N requirement of cotton.  相似文献   

5.
减氮控磷稳钾施肥对水稻产量及养分积累的影响   总被引:26,自引:8,他引:18  
氮、 磷用量偏大,钾肥用量不足不仅影响水稻的正常生长发育,而且导致养分利用率偏低。本文通过田间试验,研究减量施用氮、 磷肥,稳定钾肥投入对水稻产量、 养分积累量和肥料利用率的影响。试验设14个处理,每个处理重复2次。结果表明,氮钾、 磷钾、 氮磷钾配施处理的水稻秸秆生物量和籽粒产量均显著高于不施肥处理(P0.05); 减氮控磷稳钾处理(N 225 kg/hm2、 P2O5 60 kg/hm2、 K2O 90 kg/hm2)与常规施肥处理相比(N 300 kg/hm2、 P2O5 150 kg/hm2、 K2O 60 kg/hm2)能显著增加水稻秸秆生物量(P0.05),明显提高千粒重和籽粒产量; 试验还得出,减氮控磷稳钾处理分蘖期地上部氮、 钾含量和秸秆氮、 钾含量显著高于常规施肥处理(P0.05); 收获期地上部氮、 钾的积累量和氮、 磷的表观利用率显著大于常规施肥处理(P0.05)。适当减少氮、 磷用量, 增加钾肥用量能改善氮、 钾营养状况,促进地上部干物质的积累,提高籽粒产量和氮、 磷表观利用率。N 196.2 kg/hm2、 P2O5 46.5 kg/hm2、 K2O 90 kg/hm2的配施方案具有实际推广应用价值。  相似文献   

6.
Abstract

Root length and root distribution in the soil profile is important in determining the amount of nutrients and water taken up by the plant. Data about year to year variation of corn (Zea mays L.) root growth and its relation to nutrient uptake are limited. An evaluation of the importance of root system size and distribution on P and K uptake and corn yield was made from samples taken annually from a long‐term fertility experiment on Raub silt loam, fine silty, mixed, mesic Aquic Argiudolls. Root density varied with soil depth among years, whereas P and K fertilizer treatment had no measureable influence on total root length. Ear leaf P concentration was highly correlated with the amount of roots in the 0 to 15 cm layer which contained most of the available P. Since P was not appreciably limiting corn yield, no significant relation was found between yield and P content of the ear leaf. Yields on K deficient plots were positively correlated with root density in the topsoil. Correlations of root densities in the deeper soil layers with both yield and ear leaf nutrient concentration became increasingly smaller with depth in the soil profile. The results indicate that root length plus root distribution in the soil may influence year to year variation in yield particularily on soils having low available nutrient levels. This variation in root growth may be responsible for differences among years in the response of crops to applied P and/or K.  相似文献   

7.
Abstract. Composted domestic waste was applied either as a mulch or was incorporated into the topsoil. Mulching reduced the seasonal midday soil temperature ranges from between 14 °C and 27.5 °C to between 14 °C and 26 °C, averaging a 0.6 °C fall. However, at sub-optimal temperatures for maize production under the temperate conditions of South East England, the difference may be critical. Compost mulch also improved soil-water conservation in an average year, but not in a very dry year. Compost application increased soil-available N, but increased K uptake was considered to be more important for crop yield than either N additions or the effect on retained soil water. Overall, compost applied as a surface mulch, or incorporated into medium-textured soils in the south and east of England increased crop yield.  相似文献   

8.
生物炭具有改良耕层土壤理化性质和保水保肥的功效.针对华北地区农田养分利用效率低的问题,采用田间试验方法,研究了生物炭不同施用量对夏玉米生长关键期0~100 cm土壤有效态氮、磷、钾垂直分布特征及其对作物养分吸收利用的影响.试验设B0F(0 t/hm2生物炭+化肥)、B5F(5 t/hm2生物炭+化肥)、B10F(10 ...  相似文献   

9.
ABSTRACT

Whole crop rice (WCR) is expected to establish a cultivation method using manure produced from animal wastes. Meanwhile, application methods of fertilizer and manure in the WCR cultivation are affected by availability of manure, available time for its application, and field drainage, and low market price of WCR. This raises concerns about soil fertility deterioration and yield reduction in the WCR cultivation. The objectives of this study were to investigate how different application methods of fertilizer and manure affected soil chemical properties and yield in the WCR cultivation. Field surveys were conducted in 2013 and 2014 at 10 fields cultivated by five different farmers in the Itoshima region, Fukuoka Prefecture, Japan. The surveyed fields included two application methods of manure (M) alone and chemical fertilizer (CF) alone. Clay plus silt content was significantly correlated with total nitrogen (TN), total phosphorus (TP), and exchangeable potassium (Exch. K), which indicated that soil texture partly contributed to the variations of these soil chemical properties. Meanwhile, clear gaps of TN, TP, Exch. K, K saturation degree, and available N between CF and M at around 40% of clay plus silt content strongly suggested that manure application contributed to increases in the soil chemical properties. Yearly differences of available N had relatively large negative values in CF fields. This result suggested a possible decrease in mineralizable part of soil TN in the WCR cultivation with CF alone, which needs to be clarified through long-term study. Significant relationships between potential N supply and straw weight (= 0.698, p < 0.05 for 2013; r = 0.873, p < 0.01 for 2014) or yield of whole crop (= 0.852, p < 0.01 for 2014) indicated that N mineralized from soil, which was enhanced by manure application, increased straw weight, resulting in an increase in yield of whole crop. However, excessive amounts of manure applied in surveyed fields can cause groundwater and surface water pollution. Thus, nutrient balances in a paddy field need to be analyzed further to determine an appropriate application amount of manure.  相似文献   

10.
设施栽培黄瓜临界氮浓度和氮营养指数模拟   总被引:4,自引:1,他引:3       下载免费PDF全文
以黄瓜津春5号为试验材料,采用随机区组设计,2016和2017年分别设置了5个氮浓度梯度,构建了黄瓜地上部生物量的临界氮浓度稀释模型,在此基础上建立了氮素吸收模型和氮营养指数模型。结果表明,黄瓜地上部临界氮浓度与地上部最大生物量之间符合幂指数关系,%Nc=4. 539 7x-0. 06,相关系数为R2=0. 749 6。基于临界氮浓度建立的设施栽培黄瓜氮素吸收(Nupt)模型、氮素营养指数(NNI)模型,可作为设施栽培黄瓜氮素营养状况的判别指标,本试验条件下295. 7~305. 5 kg/hm~2为黄瓜最佳施氮量。  相似文献   

11.
土壤中氮磷钾肥转化中的交互作用: Ⅰ.土壤pH的动态变化   总被引:10,自引:0,他引:10  
Dynamic changes of soil pH as influenced by ammonium sulfate (AS), monocalcium phosphate (MCP),potassium chloride (KCl) and their interaction in soils were evaluated in incubation experiments. Applyingthese fertilizers significantly reduced soil pH values in all cases and followed sequences of AS > MCP >KCl, MCP > KCl > AS and KCl > AS > MCP for the paddy, calcareous and red soils, respectively. TheAS-induced reduction of pH in the three soils followed the sequence of red soil > paddy soil > calcareous soil,while in MCP and KCl systems the reduction of pH followed the sequences of calcareous soil > paddy soil >red soil and red soil > calcareous soil > paddy soil, respectively. The interactions of the NPK fertilizers on pHwere significant. MCP plus KCl or MCP plus AS reduced pH values more than the fertilizers applied solelyin the paddy soil, but AS partly counteracted the effect of MCP on pH in the 1 d sample of the calcareoussoil. The effect of MCP on pH was trivial when MCP was applied in combination with KCl or AS in the redsoil. When applied in combination with AS, KCl did not affect soil pH initially, but suppressed the reductionof pH at the later incubation stage, which was related to inhibition of nitrification by KCl in the soils.  相似文献   

12.
Winter wheat (Triticum aestivum L.) is an important source of forage for cattle in the southern Plains. While high in quality, wheat pasture is prone to cause thousands of cattle deaths annually from nitrate poisoning, bloat, and wheat pasture poisoning, a syndrome of unknown cause. A large portion of the stocker cattle deaths on nitrogen fertilized pastures occur from unknown causes that appear to be related to forage composition. The objectives of this study were to determine seasonal trends in nutrient composition and to determine the effect of nitrapyrin, a nitrification inhibitor, on the change in nutrient composition of wheat forage over winter. The wheat was planted the last week of August on a Pullman clay loam soil (fine, mixed, thermic Torrertic Paleustol). Clip samples were collected periodically and analyzed for nutrient composition. Nitrogen, phosphorus, and potassium concentrations of the wheat forage varied during the season. Levels tended to be highest with the onset of growth and to decline as growth was decreased by cold weather. Nitrapyrin did not affect the concentration of any of the nutrients examined in the wheat forage. Concentration of nutrients, other than potassium, tended to be highly correlated with each other in both years of the study.  相似文献   

13.
Determining genotypic responses to soil fertility may assist selection of cultivars that can be adapted to varied soil fertility regimes, and such selection under field conditions is still limited. A two-year field experiment was conducted in long-term field trials to investigate wheat genotype effects on early growth, yield and nutrient accumulation as affected by varied long-term soil fertility managements and nitrogen (N) fertilization. Results show that the early growth, grain yield and nutrient accumulation of spring wheat plants were strongly affected by soil fertility managements and genotypes. Early shoot and root biomass of singly grown plants and leaf canopy growth under standard growth density was associated with subsequent grain yield of plants under standard growth density across the gradient in soil fertility levels. Taifun and Thasos had stable higher yield and N and phosphorus (P) uptake across varied soil fertility regimes compared with other genotypes. Økilde, however, increased yield by 8–34% and N and P accumulation by 1–22% only when grown in the high organic manure treatment compared with other genotypes, indicating that it is more adapted to high organic fertility regimes. Therefore, the different responses and adaptations of genotypes to soil fertility regimes should be included during selection of cultivars.  相似文献   

14.
为解决化肥径流淋洗及养分挥发损失量大、养分释放难与作物吸收同步等问题,该研究对天然缓释材料凹凸棒土进行了300℃热改性处理,同时与生物炭相结合,制备了热改性凹凸棒土-生物炭复合材料,以期提升该材料对氮磷钾养分的缓释性能,并以小白菜进行生物效应验证。试验共设7个处理:以不施肥(CK)和普通化肥(F)做对照,设置化肥+凹凸棒土(AF)、化肥+热改性凹凸棒土(TAF)、化肥+生物炭(BF)、化肥+凹凸棒土+生物炭(ABF)、化肥+热改性凹凸棒土+生物炭(TABF)缓释。结果表明:1)天然凹凸棒土经300℃热改性后,呈现破碎及圆形塌陷结构并出现大量的间隙和裂缝,为养分离子与复合材料相互作用提供更多位点,从而对氮磷钾元素呈现出较优的吸附性能。2)相比生物炭,热改性凹凸棒土+生物炭复合材料由片层转变为疏松多孔结构,具有更多孔道和较深的孔径;同时SiO2、MgFe4(SO4)6(OH)2(H2O)20和CaMg(CO3)2含氧基团增加,提高了复合缓释材料吸附效果。3)与普通化肥(F)氮、磷养分释放高峰在第5天和第9天相比,TABF则出现在第52天和第42天,缓释效果突出。4)TABF代替化肥后,可与小白菜整个生育期对养分需求同步缓释,在表型指标、品质、产量等方面均优于CK和F处理;与普通化肥相比,5种缓释材料均能显著增加氮磷钾利用率和农学效率,其中以TABF最优。综上所述:300℃热改性显著增加了凹凸棒土的吸附位点,特别是凹凸棒土-生物炭复合材料更能有效提高肥料的缓释性能,与小白菜全生育期的养分需求同步性好,有效提高了氮磷钾利用率。  相似文献   

15.
关中地区玉米临界氮浓度稀释曲线的建立和验证   总被引:5,自引:4,他引:5  
基于临界氮浓度稀释曲线推导的氮素营养指数既可以诊断出氮素供应不足也可以诊断出氮肥供应过量。该文在整理分析关中平原8 a氮肥大田试验的基础上,分别构建了关中灌区夏玉米和渭北旱塬春玉米的地上部生物量的临界氮浓度稀释曲线模型。结果表明,关中玉米地上部临界氮浓度与生物量符合幂函数关系。利用独立试验资料对建立的临界氮稀释曲线模型进行检验,结果表明:该模型能准确诊断该区玉米植株的氮营养状况,施肥量和施肥时期对玉米植株的氮素营养状况影响较大,一般随着施氮量的增加氮素营养指数值会增大,只基施氮肥或前期施氮过多都会使玉米在生长过程中营养失衡。该研究建立的关中地区玉米的临界氮稀释模型为该区玉米氮素营养诊断和优化管理提供了较好的技术途径和理论参考。  相似文献   

16.
Abstract

Food waste, waste paper and different topsoils were composted in different experiments. The composts were characterised by high contents of N, P, S, Na and K in the food waste, of Mg in the soil, and of Ca in paper and soils. The nitrogen catching was between 50 and 70% of the input. The lowest amounts were caught in the composts with sandy soils, the highest in a clay soil with high ignition loss.  相似文献   

17.
氮磷钾配施对砂田西瓜产量和品质的影响   总被引:7,自引:2,他引:5  
【目的】施肥不平衡是影响砂田西瓜产量和品质的主要因子。研究氮、 磷、 钾不同施肥量和配施比例对砂田西瓜产量和品质的影响,探明旱砂田西瓜高产、 优质的适宜氮、 磷、 钾施用量和配比,对提高砂田西瓜的生产效率具有重要的现实意义。【方法】本研究以中晚熟西瓜品种陇抗九号为试材,在砂田西瓜全膜覆盖栽培条件下,采用氮、 磷、 钾三因素的“311-B”D饱和最优设计,进行田间微区试验。对西瓜产量和品质结果进行二次回归拟合,建立养分回归数学模型。【结果】因素效应分析结果表明,不同因素对西瓜产量的影响以磷肥最大,氮肥次之,钾肥较小; 对西瓜品质的影响以磷肥最大,钾肥次之,氮肥较小,表明在砂田碱性土壤中,磷是影响西瓜产量、 品质的首要因素,当氮、 磷、 钾肥用量分别达231.61、 204.34、 191.78 kg/hm2时,边际产量效应值降至0。氮磷、 氮钾、 磷钾的交互作用对西瓜的产量也有显著影响,某一单一肥料施用量偏高或偏低均不利于西瓜产量的形成,而由于肥料间的交互作用,两者配施则对产量的提高有较强的促进作用。对氮而言,磷的交互效应大于钾; 对磷而言,氮的交互效应大于钾; 对钾而言,磷的交互效应大于氮,其交互作用最显著的区域为N 115.0~341.8 kg/hm2、 P2O5 86.5~298.2 kg/hm2、 K2O 101.6~298.4 kg/hm2。利用模型进行决策表明,砂田西瓜产量超过50 t/hm2的施肥方案为N 193.19~238.18 kg/hm2、 P2O5 162.41~206.72 kg/hm2、 K2O 164.85~214.53 kg/hm2; 西瓜品质综合评分在85分以上的施肥方案为N 195.96~239.44 kg/hm2、 P2O5 167.86~207.52 kg/hm2、 K2O 212.87~267.62 kg/hm2。【结论】砂田西瓜产量达50 t/hm2、 品质综合评分达85分以上的施肥方案为N 195.96~238.18 kg/hm2、 P2O5167.86~206.72 kg/hm2、 K2O 212.87~214.53 kg/hm2,适宜的N、 P2O5、 K2O施用比例约为1∶0.86∶0.98。  相似文献   

18.
The effects of bark mulch and NPK fertilizers on yield and leaf and soil nutrient status of ‘Korona’ strawberry plants (Fragaria×ananassa Duch.), were studied over a period of three years. A significant effect of mulching was found in the first harvest year, but additional fertilizer did not affect total yield. Bark mulch slightly decreased the level of leaf nitrogen, but increased the level of leaf phosphorus and potassium in all years. Bark had a significant, negative effect on soil nitrate and ammonium content in the two first seasons. Mulching increased the soil moisture content in all years.  相似文献   

19.
A field experiment entitled “nitrogen and vermicompost interaction on soil and leaf nutrient status of kinnow mandarin in vertisols of Jhalawar district” was conducted at the Fruit Research Farm, Department of Fruit Science, College of Horticulture and Forestry, Jhalawar (Rajasthan) during 2012–13 to study the effect of different levels of nitrogen and vermicompost on physico-chemical properties of soil and leaf micro and macro nutrient contents of Kinnow mandarin. The result indicated that application of T15 treatment i.e. nitrogen at 350 g/plant + vermicompost 20 kg/plant was found best with regard to improvement in soil physico-chemical properties like organic carbon content (0.44%), available nitrogen (N) (379.36 kgha?1), available phosphorus (P) (25.56 kgha?1), available potassium (393.29 kgha?1) and reduces electrical conductivity (0.34 dSm?1), soil pH (7.42) and calcium carbonate (CaCO3) content percentage (15.20) of soil.  相似文献   

20.
娄土区作物和土壤淋溶磷临界值研究及推荐施磷建议   总被引:2,自引:0,他引:2  
确定临界土壤磷最佳水平及合理的施肥量可为实现作物高产和减少磷素损失提供理论依据。本研究以“国家黄土肥力与肥料效益监测基地”24年长期肥料定位试验为基础,利用长期试验积累数据并结合相关土壤分析,通过米切里西指数模型和两段式线性模型确定了土区冬小麦和夏玉米高产土壤有效磷临界值以及土磷素淋溶阈值并提出了施磷建议。结果表明,该地区冬小麦高产时土壤有效磷临界值为26.2 mg/kg,夏玉米为13.9 mg/kg。土壤有效磷随全磷的增加存在明显的临界点,当全磷含量为1.15 g/kg时,有效磷含量为34.8 mg/kg,高于此值后有效磷随全磷快速增加。土壤有效磷含量大于39.3 mg/kg时,磷素淋溶风险增大。无轮作情况下,当土壤有效磷含量分别为<25、25~40和>40 mg/kg时,冬小麦施磷量分别为P2O5 80~95、60~80和10~15 kg/hm2;当土壤有效磷<15、15~40和>40 mg/kg时,夏玉米施磷量分别为P2O5 70~85、55~70和10~15 kg/hm2。冬小麦-夏玉米轮作体系下,当土壤有效磷含量分别为<15、15~25、25~40和>40 mg/kg时,冬小麦施磷量分别为P2O5 100~120、90~100、80~90和15~20 kg/hm2,夏玉米施磷量分别为P2O5 50~60、45~50、25~40和5~10 kg/hm2。  相似文献   

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