The worth of giants: The consumptive and non‐consumptive use value of the giant sea bass (Stereolepis gigas)

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美国汉语教学和中国英语教学的比较研究

目前,社会经济全球一体化发展趋势正在逐步加强,因此,世界各国教育者及政府都在 非常关注对外语的学习,并将其空间规模扩大化。其中最突出的两个国家为:中国和美国。中国 地大物博,人口众多,学习英语的人群庞大;而美国人民对汉语言的学习也热情持续不断。由于 中国英语教学与美国汉语教学整体价值存在不同,因此,深入进行究具有重要意义。     

Impact of Pediococcus pentosaceus and Pichia anomala in combination with chitinase on the preservation of high‐moisture alfalfa hay

This study assessed the effects of applying Pediococcus pentosaceus (PED) or Pichia anomala (PIC) in combination with chitinase (CH) on the conservation characteristics and rumen digestibility of large round‐bale high‐moisture alfalfa hay (HMH). Alfalfa was wilted in the field to 23%–27% moisture and baled without (Control) or with PED + CH, PIC + CH and propionic acid (PA). The study was repeated yearly from 2012 to 2014. The PED + CH‐treated HMH had the numerically lowest high degree day (bale internal temperature >30°C) in all 3 years, which was less (p < .05) than Control HMH and PA in 2012. Treatments had no effect on pH, but mixed effects on chemical and microbial compositions across 3 years. The PED + CH treatment had the highest water‐soluble carbohydrate (WSC) content (p < .05) in 2012 and 2014, whereas PA treatment had the lowest (p < .05) WSC in these years. Total bacteria were decreased (p < .001) by PIC + CH and PED + CH in 2012 only. The PED + CH treatment had greater (p < .01) soluble fraction of dry matter (DM) than Control HMH and PA in both 2012 and 2014, but treatments did not affect the potential degradable fraction of DM. The PED + CH and PIC + CH treatments increased (p < .01) in situ neutral detergent fibre digestibility after 6, 24 and 96 hr of ruminal incubation in 2012 but not in 2014. Combinations of P. pentosaceus or P. anomala with chitinase have potential as high‐moisture hay inoculants to reduce microbial spoilage and to increase fibre digestibility.     

The impact of supplementation with Rhagodia preissii and Atriplex nummularia on wool production,mineral balance and enteric methane emissions of Merino sheep

The Australian perennial shrubs, oldman saltbush (Atriplex nummularia) and rhagodia (Rhagodia preissii), can complement the diets of sheep grazing moderate‐quality cereal residues. We compared liveweight change, organic matter digestibility, nitrogen and mineral balance, wool growth and methane emissions of Merino wethers offered oaten hay (OMD 622 g kg^?1 DM; N 9.74 g kg^?1 DM) with and without shrub biomass (substituted at 25% of OM). Diets were fed at restricted levels for 1 month. Substituting hay with shrub biomass significantly decreased liveweight loss, increased clean wool growth and increased apparent absorption of phosphorus compared to the hay alone. Substitution of hay with both saltbush and rhagodia led to over 23% greater clean wool growth. Nitrogen balance and apparent digestion of organic matter, calcium and magnesium did not vary significantly between animals on the diets. Wethers on the rhagodia and hay diets had similar enteric methane emissions, while animals offered the saltbush diet had significantly higher emissions (L/OM intake). When methane is expressed in terms of wool growth, animals on the rhagodia diet produced 26% less methane for every gram of wool.     

藜麦特性及研究现状

概述了藜麦的生物学特性、营养价值,总结分析了国内外对藜麦耐盐碱、抗旱、化学成分等方面的研究进展,探讨了国内藜麦种植现状及其推广开发存在的问题,并对其发展应用前景进行展望,以期为藜麦研究开发提供参考依据。     

表层土壤湿度和pH值对胖大海幼树幼苗更新的影响

在越南同奈天然文化自然保护区设置150个样地,运用生态学理论,采用Logitic模型和生态学统计方法,分析表层土壤湿度和pH值对胖大海幼树幼苗更新出现频率的影响.结果表明,胖大海幼树幼苗在SL1、SL2和SL3三个阶段的天然更新出现频率均与各林分胖大海的优势度、表层土壤湿度和pH值有密切关系.适合胖大海幼树幼苗更新的表层土壤湿度:SL1阶段是57.7%~78.8%,最适度是68.2%;SL2阶段是64.8%~80.7%,最适度是72.8%;SL3阶段是65%~80%,最适度是73.3%.适合胖大海幼树幼苗更新的表层土壤pH值:SL1阶段是3.5~5.7,最适度是4.6;SL2阶段是4.4~5.9,最适度是5.1;SL3阶段是5.0~6.5,最适度是5.5.胖大海的丰富度变化受表层土壤湿度和pH值2个因素的影响,其关系能够用Logit Gauss模型来表征.表层土壤湿度和pH值受森林类型影响,胖大海高优势度林分或者高稳定性林分具有更适合胖大海幼树幼苗天然更新的环境.     

盐碱地区水稻食味值及其与品质性状的关系

以辽宁省盐碱地利用研究所提供的65个水稻品系为试材,分析了这些水稻品系食味值的总体表现,及食味值与各品质性状的关系。结果表明,各参试品系品质普遍较好,但品系间各品质性状有一定差异;各参试品系食味值在60.44~84.00之间,品系间差异显著,并接近正态分布;食味值与垩白粒率、垩白度呈极显著正相关,与精米率、直链淀粉含量和蛋白质含量呈极显著负相关,与长宽比呈显著负相关。因此,在品种选育过程中,应选择直链淀粉含量和蛋白质含量相对较低,籽粒长宽比较小的品种,这样可以提高食味值。但是,食味值的提高会增加稻米的垩白粒率和垩白度。     

太湖水体中毒死蜱的污染特征及其生态风险评估

为研究太湖水体中毒死蜱的污染状况和评估其生态风险,2014年8月对太湖37个采样点位水体中毒死蜱浓度进行调查。采用固相萃取和气相色谱-质谱联用仪,对太湖水体中毒死蜱浓度进行检测。结果表明,太湖水体毒死蜱浓度在nd~13.6μg·L~(-1)之间,平均值为4.8μg·L~(-1)。采用安全阈值法对其生态风险进行评估,安全阈值(MOS10)为0.16,小于1,表明太湖水体中毒死蜱已对水生生物造成一定的生态风险。水生生物物种短期暴露于太湖水体中,太湖13.2%的水体中有超过5%的水生生物受到干扰,此时毒死蜱安全浓度上限为0.036μg·L~(-1)。该结果旨在为太湖水体中毒死蜱污染的生态风险评估提供一定的科学依据。     

东北土地利用变化的影响

根据中国东北样带上不同的土地利用组合类型作为典型区。运用GIS 和遥感技术分析近30年来不同类型区土地利用变化对生态系统服务价值的影响。本文选取基于货币量的价值量评价法,参考Costanza等人的研究成果。结合研究区的实际情况。运中国陆地生态系统服务单位面积价值的平均值来分析研究区的生态系统服务价值变化情况。研究结果表明,东北样带土地利用类型变化很大。土地利用程度均呈加大趋势,耕地、林地和草地的ESV 均有较大变动,不同类型区单位面积的ESV差别也很大。其基本分布规律为林区>农林交错区>牧区>农牧交错区>农区。敏感性分析结果表明。研究区内ESV对生态服务功能价值指数是缺乏弹性的,研究结果是可信的。     

东北黑土区土地利用变化研究

本文在GIS 与RS 技术的支持下,采用生态服务价值法对东北典型黑土地利用变化引起的生态服务价值变化进行研 究。研究表明:土地利用结构呈单一化发展趋势,在土地利用程度上其土地利用整体处于发展期;耕地、建设用地和水域呈增加 趋势,其它地类则减少,其中耕地增幅最大,为5.79％,草地减幅最多,达23.19％;15 年间生态服务总价值减少,主要原因是林地 和草地面积的减少使得生态服务总价值减少。