A meta‐analysis of the effects of dietary marine oil replacement with vegetable oils on growth,feed conversion and muscle fatty acid composition of fish species

The effects of the replacement of marine oils (MO) with canola oil (CO), linseed oil (LO) and soybean oil (SO) on growth, feed conversion and major muscle fatty acid (FA) classes were quantified using a meta‐analysis of published results. There was an absence of relationships between levels of MO replaced and effect sizes for all outcomes. High heterogeneity when combining effects sizes according to fixed effects models imposed the stratification of values in MO replacement categories and the use of random effect models to calculate the summary statistics. Limited values at 50% and 60% hampered clear tendencies when compared to 100% MO replacement. A medium mean effect size (?0.3773, 95% confidence intervals = ?0.7325 to ?0.0222, n = 22) for growth was obtained when replacing all MO with CO, whereas LO (?1.5609, 95% confidence intervals = ?2.3584 to ?0.7633, n = 19) and SO (?1.0589, 95% confidence intervals = ?1.7197 to ?0.3980, n = 22) resulted in high negative effect sizes. This study quantified the extent of differences in production parameters caused by dietary MO replacement with VO and could serve as reference for future experimental studies.     

基于贝叶斯向量自回归的区域经济预测模型：以青海为例

十七年文学出于对革命意识形态的绝对捍卫，对土匪的想象缺少了民国时期作品的丰富性，其匪类叙事反映了主流意识形态对于文学匪色想象的绝对控制和规训。然而传统英雄侠义观的根深蒂固以及古典英雄传奇叙事模式的影响使匪色想象逸出意识形态的控制，塑造了新的类型形象——具有匪性气质的革命英雄人物。同时在十七年文学中还存在一个异数——那就是诗人郭小川的叙事长诗《一个和八个》，它体现了逸出秩序之外的个性化匪色想象，也使诗人因此受到严厉的政治批判。     

施肥方式对不同密度下玉米光合生理的影响

为进一步研究玉米品种登海605不同密度和施肥方式对光合生理的影响，挖掘其增产潜力，建立高产栽培模式。本试验设计5个密度处理（D1、D2、D3、D4、D5）、3种施肥方式处理（S1：农大缓释肥、S2：分次施肥、S3：一次性施肥），并对不同处理的光合指标、叶面积指数、光合有效辐射、透光率等指标进行测定，结果表明：不同的施肥方式上层、中层、下层光合指标变化规律表现一致，各层次表现为上层>中层>下层，S2>S1>S3，玉米植株上层无论哪种处理都能获得足够的光能和CO2，光合指标相差不大，适宜的密度和施肥方式将获得更多的光能、有效辐射，合成有机物，形成更多的干物质积累，从而提高产量。     

泗阳县玉米测土配方施肥试验

为明确测土配方技术在泗阳地区玉米生产过程中的实际效果，通过田间试验对玉米生育期、产量构成和效益等进行了对比分析。试验结果显示：采用14.8-9-8的肥料配比能显著提升玉米肥料利用率，提高产量和收益。相较常规施肥，测土配方施肥对玉米生育期影响较小，但玉米穗粒数和千粒重提升效果显著，分别提升了1.88%和3.89%；测土配方施肥的氮、磷、钾肥利用率和养分平均利用率分别为40.77%、28.02%、51.18%，相较常规施肥分别提升了11.55%、4.07%、21.46%，养分平均利用率提升了12.36%；测土配方施肥籽粒产量为9535.04kg/ha，相较常规施肥增产429.99kg，增产率为4.72%，纯收益每公顷提升1269.60元。     

生态环境中重金属的化学形态转化及影响因素研究

提出了环境中重金属的化学形态发生转化的2种途径,探讨了影响此转化过程的环境条件,包括pH、氧化还原电位和吸附质表面的键合作用等。     

盐度胁迫对高体革鯻幼鱼消化酶活力的影响

研究了盐度对高体革（Scortum barcoo）幼鱼消化酶活力的影响。在温度25±2℃下,将平均体质量为2.50±0.23 g的高体革幼鱼分别饲养在盐度0,5,8,11,13和16条件下20 d,检测幼鱼胃蛋白酶、淀粉酶和脂肪酶活性的差异。结果表明：盐度胁迫对高体革幼鱼胃蛋白酶活力有显著影响（P〈0.05）,对脂肪酶和淀粉酶活力有极显著影响（P〈0.01）。随着盐度的升高,胃蛋白酶活力先升后降,当盐度升高到13时又急剧升高;脂肪酶的活力则是随盐度的升高而受到抑制,当盐度升高到13时也急剧升高,盐度16时最高;而淀粉酶活力变化则是盐度升高时显著降低。这说明环境盐度对高体革消化酶比活力的影响比较大,不同消化酶随盐度变化规律有所差异。     

耕水机在罗非鱼精养池塘的应用效果分析

选择两组罗非鱼(Tilapia)精养池塘作为研究对象,通过设置实验塘和对照塘的方法,研究耕水机的使用对精养池塘水质变化情况和养殖效果的影响.结果表明:与对照池塘相比,实验池塘的水质稳定,池水化学耗氧量的平均值降低了1.56 mg/L,总悬浮物的平均含量下降了24.3028 mg/L,总氨氮的平均浓度下降了0.2418 ...     

主要栽培技术对"姜三七"产量与药效成分的影响

研究不同种植密度、不同肥料用量和不同施肥类型对"姜三七"产量和药用成分含量的影响,为"姜三七"的人工栽培措施的制定提供依据。结果表明:种植密度与产量呈显著正相关;与不施肥(对照)相比,有机肥+复合肥组合处理增产198%,施用复合肥处理的樟脑和莰烯含量分别增加1.14%和5.74%。     

长江中游监利江段鱼卵及仔稚鱼时空分布

2010年5-7月对长江中游监利江段鱼卵和仔稚鱼的时空分布进行调查,共采集到鱼卵样品9494粒,仔稚鱼样品328422尾,分属8目15科43属51种.结果显示:5-7月鱼卵的平均密度为13.3 ind./100m3,最大密度值87.8 ind./100 m3,主要集中在5月;5-7月仔稚鱼平均密度为61.8 ind./...     

Cost-efficient light control for production of two campanula species

A cost-efficient light control system based on weather forecasts, electricity prices and daily photosynthesis integral (DPI) was evaluated for application in the commercial production of the long-day (LD) plant Campanula portenschlagiana ‘Blue Get Mee’ and C. cochlearifolia ‘Blue Wonder’. Experiments were conducted under both autumn and spring conditions and included four treatments. Three treatments were controlled by the software system DynaLight Desktop which automatically defined the most cost-efficient use of supplemental light, -based on a predefined set point of DPI, forecasted solar irradiance and the market price on electricity. The set points of DPI in the three treatments were 300, 450 and 600 mmol CO₂ m⁻² leaf d⁻¹ and the treatments were compared with a traditional LD 19-h treatment. The DPI-based light control strategy resulted in very irregular light patterns including daily periods of solar irradiance combined with supplemental light in low light periods and a night period interrupted by irregular light breaks (NB-lighting). Both campanula species flowered in the DPI-based treatments during spring, but the flowering percentage was low and non-uniform during autumn. This was caused by a combination of the irregular light, low natural light intensities and a decrease in daily light integral (DLI), and could be restored by maintaining a continuous 19 h photoperiod with incandescent lamps (<5 μmol m⁻² s⁻¹), illustrating that photoperiod was an important factor for flowering in LD species grown under low light intensities. Growth in terms of carbon gain was marginally affected by the irregular light and a 25% reduction in electricity costs was achieved without major reductions in plant quality in spring. Our results illustrate that plant production of LD species can be maintained in a cost-efficient light control system where the use of supplemental light is based on weather forecasts and electricity prices.