我国北方水田区稻-萍-蟹共生模式效益的研究     

王新  梁仁禄  李培军 《农业环境科学学报》2002,21(1):41-44

在辽宁省盘山县太平农场开展了稻-萍-蟹无公害农业模式的研究。结果表明,与对照相比,稻-萍-蟹2、3处理水稻分别增产5.79%、1.69%,而稻-萍-蟹1处理与对照相比减产2.03%,稻-萍-蟹系统增收河蟹103.95—170.85kg·hm-2;稻-萍-蟹系统与对照相比土壤全氮含量增加了12%—20%、全磷增加了15.7%—30.3%、全钾增加了40.9%—49.7%,有机质增加了20.4%—36.2%;稻-萍-蟹1、2、3处理杂草量比对照分别下降了25%、50%、15%;稻-萍-蟹共生模式是北方水田区无公害农业最佳生态模式。  相似文献   

茶(Camellia sinensis)蜂花粉及其蜂粮的营养成分研究   总被引：4，自引：0，他引：4  

苏松坤  陈盛禄 《上海交通大学学报(农业科学版)》2002,20(2):95-99

测定中国茶（Camellia sinensis)的新鲜蜂花粉，5d,10d,15d茶蜂粮中水解氨基酸的含量，茶蜂粮中平均含量为23．36％，比新鲜茶蜂花粉高0．26％，新鲜茶蜂花粉和混合（5－10d)茶蜂粮样品中游离氨基酸含量分别为1037．46mg/100g和801．75mg/100g，混合（5-10d)茶蜂粮和新鲜茶蜂花粉样品中维生素A，B1，B2，C，D，E的含量（mg/100g)分别是0．19，15，1．15，0．31，0．0156，10．2和0．79，0．09，2．74，1．20，0.0158,6.6，新鲜茶蜂花粉和混合茶蜂粮样品中软脂酸，硬脂酸，亚油酸，亚麻酸的含量分别为1．3％，0．2％，0．16％，2．5％和1．1％，1．0％，0．3％，1．0％，1d茶蜂粮中的过氧化氢酶，淀粉酶的活力比新鲜茶蜂花粉高，而过氧化物歧化酶的活力则比新鲜茶蜂花粉略低，随着酿制时间的延长，茶蜂粮中过氧化氢酶，过氧化物歧化酶的活力下降，而淀粉酶的活力增强。  相似文献   

食品资源引进研究--海南产印度辣木的营养价值评价   总被引：3，自引：0，他引：3  

周才琼  阳长敏  吴雪琴  梁国鲁 《西南大学学报(自然科学版)》2005,27(6):763-765

通过对辣木菜宏量营养素、微量营养素和重金属等指标的分析,比较新的生态环境下辣木幕的营养成分变化,并评价了印度辣木菜的营养价值。结果表明印度辣木幕中主要成分蛋白质和脂肪含量高、β-胡萝卜素和维生素C高,矿物元素以钙、铁含量最高,重金属指标低于GB。印度辣木是1种营养价值非常高的新资源食品。  相似文献   

东北黑土中CO_2和CH_4的排放量   总被引：1，自引：0，他引：1  

丁洪  王跃思  王德禄 《农业环境科学学报》2003,22(6):720-723

采用田间实验方法,研究了东北黑土中CO2和CH4的排放规律.田间测定结果表明,在东北黑土中有较大的CO2排放量,而且不同作物系统间的排放量有显著差异(P<0.05).玉米在整个生长期土壤CO2排放总量为5 258.1～6025.3kg@hm-2,大豆整个生长期排放总量为6 513.1～7 484.7kg@hm-2,土壤是大气中CO2的主要源之一.作物-土壤系统中CO2排放通量与气温有显著的正相关关系(P<0.05),与土壤水分之间无明显的相关性.CO2主要排放期出现在温度较高的6-8月份,温度是该地区CO2排放的主要限制因子.土壤-旱作系统中也产生CH4排放,不同作物系统中的排放量有显著差异(P<0.05),玉米地和大豆地中CH4的排放总量分别为1.13～2.14 kg@hm-2和0.62～0.71kg@hm-2,总排放量不大,农田旱作系统可能不是甲烷的主要源.CH4的排放通量与温度和水分无明显的相关性.  相似文献   

离体条件下玉米籽粒发育调控研究   总被引：8，自引：0，他引：8  

张凤路  赵久然  王纪华 《杂粮作物》2001,21(4):34-35

采用改进的籽粒离体培养系统对糖分浓度、GA3、ABA以及乙烯对籽粒发育的调控进行了研究，结果表明：有机营养供应状况与籽粒发育密切相关；相对较高的ABA／GA3利于籽粒的正常发育；籽粒发育的前期是对乙烯的敏感期。激素对籽粒发育的调节可能以可溶性酸生蔗糖转化酶为调节位点。  相似文献   

用酸碱滴定曲线拟合参数表征土壤对酸缓冲能力的新方法   总被引：11，自引：3，他引：11  

成杰民  胡光鲁  潘根兴 《农业环境科学学报》2004,23(3):569-573

以太湖地区3种对酸缓冲能力不同的水稻土(黄泥土、白土和乌泥土)为供试土壤,以不同pH值(pH为5.6,4.0,3.0,2.0)的模拟酸雨淋溶,研究模拟酸化条件下土壤酸碱缓冲能力的变化。根据酸碱滴定曲线,进行统计分析和数学拟合,提出以酸碱滴定曲线拟合方程的斜率表征土壤酸缓冲能力的新方法。结果表明,3种供试土壤酸碱的基础缓冲能力依次为黄泥土(β=3.25)、乌泥土(3.00)、白土(1.58);土壤酸碱滴定曲线在其突跃范围内,加酸的量与pH呈显著线性负相关;直线斜率b的绝对值用以定量土壤对酸碱缓冲能力,b的绝对值越大,土壤酸碱缓冲能力越差。K值用以定量说明土壤酸碱缓冲能力的变化,当K>100%时,K值越大,土壤酸缓冲能力降低越多;当K<100%时,K值越小,土壤酸碱缓冲能力增加越大;当K≈100%(≤±5%)时,可视为土壤酸碱缓冲能力无显著变化。因新方法的理论依据仍为酸碱滴定曲线的理论,所以仅适用于反应动力学上较快的阳离子交换反应,即土壤酸碱初级缓冲体系,不适用于原生矿物的风化的土壤酸碱次级缓冲体系。其结果为研究土壤酸碱缓冲能力的变化,乃至研究土壤环境质量变化提供了可靠的定量方法。  相似文献   

《园林制图》教学改革体会与思考     

彭璐  韦松林  CHEN xiao-juan  CAI ru  LI hong-bin 《农业与技术》2007,27(3):169-172

从教学内容、教学策略、实践教学改革、综合素质培养几个方面分析《园林制图》课程教学改革的主要思路,解析了课程教学改革对于促进学生综合素质发展的重要意义。  相似文献   

Effects of Sowing Dates and Seeding Rates on Nitrogen and Water Use Efficiency of Facultative Wheat     

Bulut  Sancar  Çağlar  Özcan  Öztürk  Ali 《Gesunde Pflanzen》2022,74(2):291-301

In this study, effects of different sowing dates and seeding rates on N uptake efficiency (NUE), N translocation efficiency (NTE), agronomic efficiency (AE), physiological efficiency (PE), water use efficiency for grain yield (WUE_g) and water use efficiency for biomass (WUE_b) of facultative wheat were investigated. As the average of cropping year, sowing dates and seeding rates, N uptake efficiency (NUE), N translocation efficiency (NTE), agronomic efficiency (AE), physiological efficiency (PE), water use efficiency for grain yield (WUE_g) and water use efficiency for biomass (WUE_b) values were respectively obtained as 1.17?kg N_uptake/kg N_applied, 68.5%, 36.9?kg grain/kg N_applied, 31.2?kg grain/kg N_uptake, 5.19?kg ha^?1 mm^?1 and 18.04?kg ha^?1 mm^?1.

Nitrogen and water use efficiencies decreased with delayed sowing dates and increased with increasing seeding rates. It is possible to maintain a high wheat yield, nitrogen and water use efficiency by increasing plant density through winter sowing. It was concluded based on present findings that sowing date and seeding rates had significant effects on nitrogen and water use efficiencies and winter sowing should be practiced as not to cause yield losses and high seeding rates (575 seeds m^?2) yielded greater nitrogen-water use efficiencies.

  相似文献   

Biosorption of Methylene Blue from Aqueous Solutions by Hazelnut Shells: Equilibrium, Parameters and Isotherms     

Mehmet Doğan  Harun Abak  Mahir Alkan 《Water, air, and soil pollution》2008,192(1-4):141-153

This paper presents a study on the batch adsorption of a basic dye, methylene blue (MB), from aqueous solution onto ground hazelnut shell in order to explore its potential use as a low-cost adsorbent for wastewater dye removal. A contact time of 24 h was required to reach equilibrium. Batch adsorption studies were carried out by varying initial dye concentration, initial pH value (3–9), ionic strength (0.0–0.1 mol L^?1), particle size (0–200 μm) and temperature (25–55°C). The extent of the MB removal increased with increasing in the solution pH, ionic strength and temperature but decreased with increase in the particle size. The equilibrium data were analysed using the Langmuir and Freundlich isotherms. The characteristic parameters for each isotherm were determined. By considering the experimental results and adsorption models applied in this study, it can be concluded that equilibrium data were represented well by Langmuir isotherm equation. The maximum adsorption capacities for MB were 2.14?×?10^?4, 2.17?×?10^?4, 2.20?×?10^?4 and 2.31?×?10^?4 mol g^?1 at temperature of 25, 35, 45 and 55°C, respectively. Adsorption heat revealed that the adsorption of MB is endothermic in nature. The results indicated that the MB strongly interacts with the hazelnut shell powder.  相似文献   

The investigation of the effects of different feeding strategies on the growth of dolphin cichlid (Cyrtocara moori Boulenger, 1902) fish          下载免费PDF全文

Ebru Yılmaz  Remzi Oğuz Arık  Bünyamin Arı  Abdullah Yılmaz  Ali Gök 《Aquaculture Research》2018,49(9):3004-3010

This study was designed to investigate the effects of restrictive and cyclical feeding on the growth parameters of dolphin cichlid (Cyrtocara moorii Boulenger, 1902). In the study, 300 dolphin cichlid with an initial average weight of 1.12 ± 0.23 g were placed in 15 aquariums (each of them were 60 L). The five experimental groups, were designed as; the control group (A), feeding until satiation twice a day for 90 days, starvation for 1 week (B), starvation for 2 weeks (C), starvation for 1 day/satiation for 3 days (D), starvation for 1 day/satiation for 1 day (E); and the study was carried out in three repetitions. At the end of the study, groups B, C and D showed partial compensatory growth. The highest weight gains and specific growth rates were observed in control group (A), followed by groups B, C and D (p > 0.05). The lowest weight gain was observed in group E (p < 0.05). The feed conversion ratio did not show any significant difference between the groups (p > 0.05). In terms of feed consumption ratio, Control, C and D groups consumed similar amounts of feed (p > 0.05), while B and E groups consumed less feed (p < 0.05) than the other groups.  相似文献