旺得丰有机-无机生物复混肥与比斯美生物有机肥在水稻上的使用效果比较

[目的]探讨旺得丰有机-无机生物复混肥与比斯美生物有机肥在水稻上的应用效果。[方法]进行田间试验,室内考种分析,探讨2种肥料在水稻上的应用效果。[结果]旺得丰有机-无机生物复混肥与比斯美生物有机肥处理的水稻,表现为熟期提早,植株矮壮,后期熟相好。虽有效穗比对照分别有所减少,但穗粒数、结实率、千粒重均有所增加。比斯美生物有机肥处理的水稻与对照平产,旺得丰有机-无机生物复混肥处理的水稻产量比对照增加0.54个百分点。[结论]旺得丰有机-无机生物复混肥具有较好的肥效,比斯美生物有机肥肥效不明显,能够节省化肥的使用。     

不同氮肥对污染土壤玉米生长和重金属Cu、Cd吸收的影响

采用盆栽试验研究污染红壤不同氮肥处理对玉米生长和吸收重金属Cu和Cd的影响。结果表明,尿素和硝酸钙处理玉米生物量高于低硫酸铵用量处理和对照处理。在污染土壤中施入高氮量的尿素较其他处理有利于玉米生长和降低玉米植株体内重金属含量。与对照相比,尿素和硫酸铵的施用降低土壤pH值,从而增加红壤水溶态以及盐提取态Cu、Cd含量;硝酸钙处理升高土壤的pH值,降低盐提取态Cu含量。用1.0 mol/L NH₄NO₃盐提取态或水溶态根区土壤重金属含量能够很好地预测玉米对Cu和Cd的吸收。在Cu和Cd污染的酸性土壤上种植玉米,施加高用量尿素或者低用量硝酸钙来促进玉米生长和降低重金属含量,避免硫酸铵氮肥的施用。     

稻草还田腐熟与化肥配施对晚稻产量及土壤理化性状的影响

稻草还田腐熟可以改善土壤理化性状,对水稻生长的经济性状指标有一定的影响,稻草还田腐熟后提供的氮、磷、钾营养元素可以减施化肥用量。试验中与无稻草还田常规施肥相比,稻草还田腐熟,以氮磷肥用量减少10%,钾肥用量减少10%~20%为宜,可使当季土壤有机质含量增加0.1~0.2 g/kg,提高0.3%~0.6%,而产量、产值和纯收益无明显差异。     

微咸水加肥灌溉下陶瓷灌水器与迷宫流道灌水器的抗堵塞性能

为探求微孔陶瓷灌水器与迷宫流道灌水器在不同水质灌溉条件下抗堵塞性能的差异及堵塞机理,本研究选择了微咸水(A1)、肥水(A2)、微咸水加肥(A3)3种不同水质,分析管间式微孔陶瓷灌水器和6种常用的迷宫流道灌水器在不同水质灌溉条件下的平均相对流量变化规律,并用X射线衍射仪测定堵塞物质组成成分,用场发射扫描电镜观测堵塞物质表面微观形貌及动态生长过程。结果表明：各灌水器的流量随着灌溉运行时间的推移均发生不同程度的下降,其中A1处理下陶瓷灌水器的流量下降最慢,表现出优于迷宫流道灌水器的抗堵塞性能,A2、A3处理下陶瓷灌水器的平均相对流量下降速度先慢后快,试验结束时平均相对流量降幅最大,抗堵塞性能较差;A1处理下堵塞物质的主要成分是CaCO3,A2、A3处理下堵塞物质的主要成分是(NH4)2SO4;A1处理下各灌水器堵塞物表面微观形貌的生长过程为晶体颗粒不断团聚,A2、A3处理下堵塞物的动态生长过程为絮状物不断黏合成板块状或膜状。陶瓷灌水器堵塞发生在内壁上,堵塞物未进入到灌水器内部微孔中,随着堵塞物质增多且变得紧密复杂逐渐覆盖了内壁上的孔隙导致堵塞;迷宫流道灌水器是由于堵塞物质在流道内沉积导致过水断面减小,从而造成堵塞。研究结果可为陶瓷灌水器的应用及改进提供参考。     

控释肥配施玉米秸秆对麦季土壤酶活性及养分的影响

为了探究控释尿素掺混肥与玉米秸秆长期互作对麦季土壤酶活性和土壤养分状况的影响,基于华北平原棕壤区小麦—玉米轮作8年定位施肥试验,对比研究了玉米秸秆还田(S)与不还田条件下施用控释尿素掺混肥(CRF)与普通尿素掺混肥(BBF)对麦季土壤酶活性及土壤养分的影响。结果表明:秸秆不还田条件下,CRF处理较BBF处理显著提高土壤中性磷酸酶(返青期和成熟期)、蔗糖酶(返青期和孕穗期)和纤维素酶(返青期和孕穗期)活性及成熟期有机质、硝态氮和有效磷含量,其中,成熟期中性磷酸酶活性显著提高29.6%,硝态氮含量显著提高34.8%。秸秆还田条件下,BBF+S处理成熟期脲酶、纤维素酶,孕穗期中性磷酸酶活性显著高于CRF+S处理,其他时期2种类型掺混肥土壤酶活性无显著差异。CRF+S处理成熟期土壤全氮、有机质、硝态氮和有效磷含量显著高于BBF+S处理。氮肥种类和玉米秸秆还田的交互作用对土壤中性磷酸酶、蔗糖酶和纤维素酶活性及土壤全氮、硝态氮、铵态氮、有效磷和速效钾含量影响显著,秸秆还田较不还田处理显著提高中性磷酸酶、蔗糖酶活性、速效钾和有效磷含量。综上表明,玉米秸秆还田和不还田条件下控释尿素掺混肥较普通尿素掺混肥处理均能显著增加土壤有机质含量,提高小麦后期速效氮磷养分的供应强度和供应容量,其中玉米秸秆还田配施控释尿素掺混肥处理在提高土壤酶活性和土壤养分方面表现最优。研究结果可为秸秆还田下氮肥优化施用提供理论依据。     

Comparison of Antioxidant Activity and Antioxidant Components in Lettuce,Onion and Tomato Obtained with Different Levels and Forms of Nitrogen Fertilization

The effect of N levels and sources on the antioxidant components in vegetable is not completely understood. Therefore, greenhouse experiments were conducted to determine the changes in antioxidant capacity diphenyl-2-picrylhydrazyl （DPPH） and ferric reducing antioxidant power （FRAP）, total phenolics, ascorbic acid, total carotene and lycopene contents in edible portions of lettuce, onion and tomato due to different nitrogen levels and sources. The experiment included three N levels （20, 40 and 60 kg/ha for lettuce trial and 60, 120 and 180 kg/ha for either onion or tomato） and four nitrogen sources （calcium nitrate, ammonium sulphate, ammonium nitrate and urea）. The antioxidant capacity and phenolic contents in lettuce was enhanced under low nitrogen level, while the antioxidant capacities, phenolics, carotenoids and lycopene in tomato fruits were not significantly affected by the nitrogen dose applied. Application of calcium nitrate caused 50% increase in DPPH and 20% in FRAP of lettuce compared to other nitrogen forms. Tomato treated with calcium nitrate or ammonium sulphate had higher phenolic and ascorbic acid contents than treated plants with ammonium nitrate or urea. Antioxidant tested parameters of onion were not significantly affected by the nitrogen treatments. Nitrogen concentration in tomato fruits significantly correlated with FRAP antioxidant capacity, phenolics, ascorbic acid, carotene and lycopene contents.     

Soil CO2 and N2O Emissions in Maize Growing Season Under Different Fertilizer Regimes in an Upland Red Soil Region of South China

Upland red soils have been identified as major CO2 and N2O sources induced by human activities such as fertilization. To monitor characteristics of soil surface CO2 and N2O fluxes in cropland ecosystems after continuous fertilizer applications over decades and to separate the respective contributions of root and heterotrophic respiration to the total soil CO2 and N2O fluxes, the measurements of soil surface CO2 and N2O fluxes throughout the maize growing season in 2009 were carried out based on a fertilization experiment （from 1990） through of the maize （Zea mays L.） growing season in red soil in southern China. Five fertilization treatments were chosen from the experiment for study： zero-fertilizer application （CK）, nitrogen-phosphorus- potassium （NPK） fertilizer application only, pig manure （M）, NPK plus pig manure （NPKM） and NPK with straw （NPKS）. Six chambers were installed in each plot. Three of them are in the inter-row soil （NR） and the others are in the soil within the row （R）. Each fertilizer treatment received the same amount of N （300 kg ha-1 yr-1）. Results showed that cumulative soil CO2 fluxes in NR or R were both following the order： NPKS〉M, NPKM〉NPK〉CK. The contributions of root respiration to soil CO2 fluxes was 40, 44, 50, 47 and 35% in CK, NPK, NPKM, M and NPKS treatments, respectively, with the mean value of 43%. Cumulative soil N2O fluxes in NR or R were both following the order： NPKS, NPKM〉M〉NPK〉CK, and soil N2O fluxes in R were 18, 20 and 30% higher than that in NR in NPKM, M and NPKS treatments, respectively, but with no difference between NR and R in NPK treatment. Furthermore, combine with soil temperature at -5 cm depth and soil moisWxe （0-20 cm） together could explain 55-70% and 42-59% of soil CO2 and N2O emissions with root interference and 62- 78% and 44-63% of that without root interference, respectively. In addition, soil CO2 and N2O flUXeS per unit yield in NPKM （0.55 and 0.10 kg C t^-1） and M （0.65 and 0.13 g N t^-1） treatments were lower than those in other treatments. Therefore, manure application could be a preferred fertilization strategy in red soils in South China.     

脲醛树脂及三聚氰胺改性脲醛树脂对桉木热解液组分的影响

为了有效利用热解技术处理废弃人造板,采用气质联用技术对比分析桉木、添加质量分数10% 脲醛(UF)树 脂的桉木、添加质量分数10%三聚氰胺改性脲醛(MUF)树脂的桉木、UF 树脂、MUF 树脂的热解液组分。结果表 明:桉木热解液成分复杂,其中2,5-二甲基呋喃的相对含量达到27.56%,3-甲基-2-羟基-2-环戊烯-1-酮和4-(2-氧 代)-2-环己烯-1-酮的相对含量分别为7.04%和7.02%,2,6-二甲氧基苯酚的相对含量为9.48%。添加UF 树脂的 桉木热解液检测到含氮物质的相对含量比桉木热解液增加22.93%,该热解液有望用于肥料生产和土壤改良;添加 MUF 树脂的桉木热解液出现了木糖、丁内酯等桉木热解液中未检测到的产物。      

多酶金缓释尿素对土壤氮素形态和含量及油菜产量的影响

采用盆栽试验和室内分析化验相结合的方法,研究了多酶金缓释尿素对油菜田土壤氮素及油菜植株全氮含量、氮肥利用率和土壤氮素依存率的影响。结果表明,多酶金缓释尿素在石灰性褐土中抑制尿素水解显著有效作用时间在油菜移栽后20 d以内,20 d以后多酶金缓释尿素处理的土壤铵态氮、硝态氮和无机氮分别为5.26,9.08,14.34 mg/kg,显著高于多酶金尿素和普尿;多酶金缓释尿素处理的土壤有机氮、全氮和植株全氮比多酶金尿素和普尿分别提高了13.55%,13.67%,9.85%和21.75%,21.82%,19.60%,且差异显著;多酶金缓释尿素处理的氮肥利用率最高,为45.19%,土壤氮素依存率和氮素损失最低,分别为40.13%和1.21 g/盆,而多酶金尿素处理的油菜产量比多酶金缓释尿素和普尿分别提高了5.38%,8.11%,这可能与肥料释放养分特点和油菜生长特性有关。     

有机无机肥配施对烤烟生长及产质量的影响

以K326为材料,通过田间试验,研究了有机无机肥与化肥配施对烤烟生长发育、产量及质量的影响。结果表明:施用贝斯特有机无机肥(T4处理)和圣农有机无机肥能够促进烟株生长,显著地提高烤烟的产量和产值。T4处理的烤后烟叶外观质量较好,内在化学成分更协调,感官质量评吸结果最佳。