天目湖流域茶园非点源污染多尺度模拟

为定量评估茶园开发非点源污染产出对流域水环境的影响,本研究利用遥感手段揭示天目湖流域2000—2019年土地利用的时空变化特征,解析土地利用的数量结构和空间格局,并集成SWAT模型与APEX模型构建基于“源-汇”的一系列要素和过程的多尺度集成模拟方法。天目湖流域土地利用变化分析结果显示,规模化开发茶园后,该地呈现水源涵养区茶园集中成片、水库周边茶园向上游持续蔓延的特征。APEX-SWAT集成模型在天目湖流域取得了较好的模拟精度,模拟结果表明：规模化茶园开发后,茶园用地类型对天目湖流域的氮磷负荷贡献持续上升,至2019年,茶园总氮产出贡献超出其他土地利用类型成为第一贡献者,总磷产出仅次于耕地成为第二贡献者,洙漕河流域和平桥河流域成为两大重点氮磷产出的茶园聚集区。针对茶园的施肥削减、过滤带设置和退茶还林3种减污措施的情景模拟结果显示,退茶还林措施的氮磷削减效果最佳,其次为10 m过滤带设置,最后为20%施肥量削减。研究建议根据当地实际情况与经济效益,将水源涵养区高氮磷流失的茶园区转换为林地,并结合过滤带设置与避免雨前施肥等措施,实现丘陵山区茶园开发影响下的水源地水生态保护调控。     

小白菜‘四月慢’与自交系05-51的组培再生比较研究

以不同器官为研究对象,对小白菜常规种‘四月慢’与自交系种质材料05-51的组培再生体系进行比较分析,为小白菜的遗传转化和种质创新提供重要的理论支持与技术保障。试验结果表明,以带柄子叶为外植体诱导不定芽效果较好;MS培养基中3 mg/L的6-BA与0.5 mg/L的NAA组合有利于不定芽形成。不同基因型之间的再生频率差异较大,与自交系种质材料05-51相比,常规种四月慢更易再生。     

不同灌水量对日光温室番茄耗水规律的影响

通过温室膜下滴灌实验,研究不同灌水量对日光温室番茄耗水规律的影响.结果表明:番茄整个生育期耗水量随着灌水量增加而增加,各处理耗水量均表现为结果盛期结果前期结果后期营养生长期;番茄整个生育期耗水强度随着灌水量增加而增加,各处理耗水强度均表现为结果盛期营养生长期结果前期结果后期.在滴灌条件下,作物耗水量为448 mm时番茄产量最高,可达9 151 kg/666.7 m2.     

Predicting corn digestible and metabolizable energy content from its chemical composition in growing pigs

Background

The nutrient composition of corn is variable. To prevent unforeseen reductions in growth performance, grading and analytical methods are used to minimize nutrient variability between calculated and analyzed values. This experiment was carried out to define the sources of variation in the energy content of corn and to develop a practical method to accurately estimate the digestible energy (DE) and metabolisable energy (ME) content of individual corn samples for growing pigs. Twenty samples were taken from each of five provinces in China (Jilin, Hebei, Shandong, Liaoning, and Henan) to obtain a range of quality.

Results

The DE and ME contents of the 100 corn samples were measured in 35.3 ± 1.92 kg growing pigs (six pigs per corn sample). Sixty corn samples were used to build the prediction model; the remaining forty samples were used to test the suitability of these models. The chemical composition of each corn sample was determined, and the results were used to establish prediction equations for DE or ME content from chemical characteristics. The mean DE and ME content of the 100 samples were 4,053 and 3,923 kcal/kg (dry matter basis), respectively. The physical characteristics were determined, as well, and the results indicated that the bulk weight and 1,000-kernel weight were not associated with energy content. The DE and ME values could be accurately predicted from chemical characteristics. The best fit equations were as follows: DE, kcal/kg of DM = 1062.68 + (49.72 × EE) + (0.54 × GE) + (9.11 × starch), with R² = 0.62, residual standard deviation (RSD) = 48 kcal/kg, and P < 0.01; ME, kcal/kg of dry matter basis (DM) = 671.54 + (0.89 × DE) – (5.57 × NDF) – (191.39 × ash), with R² = 0.87, RSD = 18 kcal/kg, and P < 0.01.

Conclusion

This experiment confirms the large variation in the energy content of corn, describes the factors that influence this variation, and presents equations based on chemical measurements that may be used to predict the DE and ME content of individual corn samples.     

RNA干扰水牛MTPN基因对颗粒细胞增殖、凋亡及激素分泌的影响

本研究旨在探讨敲低MTPN基因对体外培养水牛颗粒细胞增殖、凋亡及雌激素、孕酮分泌的影响。应用RNAi技术敲低颗粒细胞中MTPN基因的表达水平,通过实时荧光定量PCR方法检测体外培养水牛颗粒细胞中MTPN基因及增殖和周期相关基因的表达情况,CCK-8法检测细胞增殖,借助流式细胞仪检测细胞周期的分布,采用ELISA试剂盒检测细胞培养液中雌激素与孕酮含量。结果显示,经siRNA(si-MTPN)转染颗粒细胞后,MTPN基因相对表达量下降60%(P<0.01);细胞增殖受到显著抑制(P<0.05),G1期细胞数量下降,S期细胞数量上升,G2期细胞数量极显著上升(P<0.01),细胞被阻滞在G2期;增殖与周期相关基因Cyclin D2、Cytochrom C表达量显著上升(P<0.05),Caspase9、Fas基因表达量极显著上升(P<0.01);ELISA检测雌激素和孕酮分泌水平均显著下降(P<0.05)。综上表明,敲低MTPN基因能通过调控相关基因的表达抑制体外培养水牛颗粒细胞的增殖及雌激素、孕酮的分泌水平,为阐明MTPN基因参与家畜卵泡发生的分子机制提供参考。     

Sex-related differences in leaf morphological and physiological responses in Hippophae rhamnoides along an altitudinal gradient

In most woody plants, leaf morphological and physiological characteristics are extremely variable across environmental gradients, particularly across altitudinal gradients. Hippophae rhamnoides L., a dioecious and deciduous shrub species, occupies a wide range of habitats in the Wolong Nature Reserve, southwest China. We measured growth, sex ratio and morphological and physiological characteristics of leaves in male and female H. rhamnoides individuals along an altitudinal gradient. Shoot height (HT), leaf N concentration per unit dry mass (N(mass)), leaf N concentration per unit area (N(area)) and leaf carbon isotope composition (delta(13)C) were higher in males than in females, whereas females had higher specific leaf area (SLA), stomatal length (SL) and stomatal index (SI) (i.e., total stomatal length per unit leaf area) than males along the altitudinal gradient. Females also had higher values of stomatal density (SD) at all altitudes except 2800 m. The male:female ratio (MFR) was biased toward males at all altitudes except at 2800 m. Changes in HT, MFR, SLA, SD, SL, SI, N(mass), N(area) and delta(13)C along the altitudinal gradient were nonlinear. Below 2800 m, HT, SLA, SD, SL and SI increased with increasing altitude, but above 2800 m they decreased with increasing altitude. In contrast, MFR, N(mass), N(area) and delta(13)C showed the opposite patterns with altitude. Consequently, we confirmed our hypotheses: (1) stressful environments have a more negative impact on females than on males in a variety of ways; (2) under optimal growth conditions the sex ratio is even, but becomes male-biased as resources become limited; and (3) there is an optimum altitudinal range at around 2800 m for the growth of H. rhamnoides in the Wolong Nature Reserve.     

山东省植物新分类群

本文发表了山东省植物４个新变种，即光叶黄榆ＵｌｍｕｓｍａｃｒｏｃａｒｐａＨａｎｃｅｖａｒｇｌａｂｒａｔａＤ．Ｋ．Ｚａｎｇ、山东梨ＰｙｒｕｓｈｏｐｅｉｅｎｓｉｓＹｕｖａｒ．ｓｈａｎｄｏｎｇｅｎｓｉｓＤ．Ｋ．ＺａｎｇｅｔＰ．Ｃ．Ｈｕａｎｇ、泰山腹水草Ｖｅｒｏｎｉｃａｓｔｒｕｍｓｉｂｉｒｉｃｕｍ（Ｌ．）Ｐｅｎｎ．ｖａｒ．ｔａｉｓｈａｎｅｎｓｉｓＤ．Ｋ．Ｚａｎｇ和沿海胡桃楸ＪｕｇｌａｎｓｍａｎｄｓｈｕｒｉｃａＭａｘｉｍ．ｖａｒ．ｍａｕｒｉｔｉａｎａＤ．Ｋ．ＺａｎｇｅｔＰ．Ｃ．Ｈｕａｎｇ。     

四川农业大学校园环境规划分析

本文分析了四川农业大学校园形成与发展的过程以及其各功能区的组成与联系,就知识经济、开放社会形势下缺乏统一规划的老校园的发展与改造,进行深入的讨论。提出：结合自身特点,迎合时代发展的逐步完善、逐步发展的动态体系的规划指导思想。     

河北省麦田保水剂筛选及其节水效果评价

采用大田试验方法,以自然生长状态的冬小麦为对照(CK),在藁城试验区和深州试验区研究了6种保水剂(BS-1、BS-2、BS-3、BS-4、BS-5、BS-6)对河北省冬小麦麦田棵间蒸发、生长发育、产量和水分利用的影响,筛选出2种节水增产效果较好的保水剂(BS-1和BS-4),在藁城试验区进行了进一步应用评价。结果表明,(1)保水剂可显著降低麦田棵间蒸发量。其中,BS-2和BS-4处理最为显著,其全生育期棵间蒸发量分别比对照平均减少30.0%和33.9%。(2)保水剂可促进小麦根系生长和发育。至开花期,保水剂处理平均次生根条数和根系干物质积累分别比对照高9.4%和1.5%。(3)保水剂可促进冬小麦地上部干物质积累,尤其是BS-4处理最明显。至完熟期,藁城和深州两试验区BS-4处理均最高,分别为1 910.4g/m2和1 821.7g/m2,分别比对照高10.3%和18.5%。(4)6种保水剂处理均可提高冬小麦产量、水分利用效率,降低耗水量。其中,BS-2和BS-4对产量促进最显著,分别比对照提高10.9%及10.3%。BS-1和BS-4处理耗水量较低,分别比对照降低10.0%和9.7%。6种保水剂处理水分利用效率平均比对照提高12.9%。(5)施用保水剂BS-1或BS-4,单次减少灌水量450m3/hm2时,可使产量与对照无显著差异。     

新疆额尔齐斯河流域北屯段景观格局及破碎化

利用多波段遥感影像数据和地理信息系统技术,结合植被图及外业调查,采用多个景观格局指数首次定量分析新疆额尔齐斯河流域景观空间格局及破碎化特征.借助ERDAS image8.7软件,将额河流域景观类型划分为7大类10小类,其中包括5大类8小类植被类型,影像总的分类精度达到87.2%.5大类植被类型面积比例分别为耕地16.5%、河漫滩林地2.6%、湿地1.6%、草地10.5%、荒漠52.2%.格局指数分析表明;河漫滩林地在景观中呈小斑块分布,其斑块最大周长和最大面积及平均面积均小于其他植被类型;河漫滩林地的斑块形状比较复杂,其平均斑块形状指数、平均斑块分维数和类型边界密度指数均高于其他植被类型;多个景观指数都表明河漫滩林地在景观中的破碎化程度最高,这主要是由于河漫滩林地丰富的生物多样性和资源富集性吸引了人类高强度的干扰所致.额河流域景观类型面积分布最不均匀,但景观类型斑块数分布相对较均匀.