1990—2015年内蒙古高原土壤风蚀时空差异特征

基于RWEQ模型定量反演了1990-2015年内蒙古高原不同季节土壤风蚀模数,分析不同季节土壤风蚀差异,揭示植被覆盖对土壤风蚀的响应阈值。结果表明:不同季节土壤风蚀量差异较大,春季、夏季、秋季、冬季土壤风蚀量比例为5.42∶1.00∶1.36∶3.00;土地利用/覆盖状况对土壤风蚀具有重要的影响,不同季节有明显差异,植被覆盖退化后土壤风蚀模数增大,反之降低了土壤风蚀模数,尤其春季中、低覆盖度草地相互转化对土壤风蚀的作用明显;植被覆盖达到75%时可有效抑制土壤风蚀,春季与冬季低覆盖度植被对抑制土壤风蚀作用敏感于高覆盖度植被,当植被覆盖度达20%~25%时可迅速降低土壤风蚀模数。     

七星瓢虫对萝卜蚜和桃蚜捕食功能的初步研究

七星瓢虫（Ｃｏｃｃｉｎｅｌｌｓｅｐｔｅｍｐｕｎｃｔａｔａ）是山东十字花科菜田捕食菜蚜（萝卜蚜Ｌｉｐａｐｈｉｓｅｒｙｓｉｍｉ和桃蚜Ｍｙｚｕｓｐｅｒｓｉｃａｅ）的天敌优势种，其捕食能力强、发生盛期较莱蚜早，对莱蚜发生具较强的自然控制能力．室内研究了七星瓢虫各龄幼虫及成虫对萝卜蚜和桃蚜的捕食功能反应，结果表明，其功能反应均属ＨｏｌｌｉｎｇⅡ型；七星瓢虫对萝卜蚜和桃蚜均具较大的捕食潜力；１、２龄幼虫捕食量较小，且差异不大，而３龄后捕食量迅速上升，至产卵前成虫达高峰，同样条件下七星瓢虫对桃好的捕食量大于对萝卜好的捕食量；模拟后的各方程理论值与实测值相差不大，相关系数（ｒ）均大于０．９９．     

庐山楼梯草总黄酮提取工艺的优化

为研究庐山楼梯草(Elatostema stewardii Merr.)总黄酮的提取工艺,以乙醇溶液为溶剂,在单因素试验基础上利用响应曲面法的中心组合设计,对庐山楼梯草总黄酮提取工艺参数进行优化分析.结果表明,提取庐山楼梯草总黄酮的最优工艺条件为乙醇体积分数55％、提取温度80℃、液料比37∶1 (V/m,mL∶g)、提取时间2.4 h、提取2次,该条件下庐山楼梯草总黄酮提取率为5.14％.     

响应曲面法分析小麦啤酒糖化工艺参数对麦汁收得率的影响

为提高小麦辅料麦汁浸出物收得率,采用四因素五水平(1/2实施)二次正交旋转组合设计安排试验,研究糖化工艺参数对麦汁浸出物收得率影响,对小麦啤酒糖化工艺参数进行优化.利用SAS软件对试验数据进行响应面分析,得到最佳糖化工艺参数为:小麦芽比例40.0%,52℃保温时间为36 min,65℃保温时间为72 min,水料比4.7(W/V),在此条件下麦汁浸出物收得率为69.05%     

基于响应面法的多砾石砂土滴灌春小麦水肥条件优选

【目的】研究多砾石砂土土质条件下不同水肥处理对滴灌春小麦生长发育的影响,为阿勒泰地区小麦的水肥施用提供指导。【方法】设置30 mm(W₁)、45 mm(W₂)、60 mm(W₃)3个灌水水平及尿素施用0 kg/hm²(N₀)、300 kg/hm²(N₁)、600 kg/hm²(N₂)3个施肥水平,利用方差分析及响应面法进行结果优选。【结果】同一灌水水平下,N₀处理相比N₁、N₂处理春小麦株高及干物质积累量较低,其中N₀处理与N₂处理株高和干物质积累量差异显著(P<0.05);同一施肥水平下春小麦株高及干物质积累量随着灌水量增加逐渐增加。灌水量对有效穗数有显著影响(P<0.05),对千粒重无显著影响(P>0.05)。施肥量对千粒重和有效穗数无显著影响(P>0.0...     

酸模叶蓼对重金属 Pb胁迫的生理响应

采用水培法,研究不同质量浓度[0 mg/L （对照）、200 mg/L、600 mg/L、800 mg/L ]Pb处理对酸模叶蓼叶片枯黄比例、叶绿素含量及各种抗氧化酶活性等生理生态指标的影响。结果表明：随着Pb质量浓度的增加,酸模叶蓼的叶片枯黄比例逐渐增加,完全展开叶数逐渐减少,植株生长受到显著抑制;酸模叶蓼幼苗的生物量呈下降趋势;酸模叶蓼叶片的丙二醛含量、相对电导率、超氧化物歧化酶活性均呈升高的趋势,叶绿素a、叶绿素b和总叶绿素含量表现为逐渐下降的趋势,过氧化物酶活性则呈先升高后降低的趋势。在3种Pb浓度胁迫下,15 d内酸模叶蓼体内的Pb积累量分别达到30．21、75．86、100．25 mg/kg ;Pb在酸模叶蓼根中以醋酸提取态、盐酸提取态为主,而在茎、叶中则以盐酸提取态为主。酸模叶蓼对Pb具有一定的富集作用。     

黄红紫泥油菜肥料效应研究

根据田间试验结果，建立了四川丘陵区黄红紫泥土壤油菜肥料效应函数模型．结果表明磷的效应最大，其次是氮和钾．当施肥水平小于０．２５时，Ｋ＞Ｎ，超过０．２５时，Ｎ＞Ｋ．ＮＰ和ＮＫ对油菜产量具有显著正交互效应，而ＰＫ为显著负交互效应．交互效应大小随施肥水平的增加而提高。通过计算机模拟获得了油菜最高产量和最经济的肥料配方．分析了肥料对油菜产量结构的影响，提出了最适产量结构指标。     

Immunostimulatory effects of dietary fructooligosaccharides on red swamp crayfish,Procambarus clarkii (Girard)

Fructooligosaccharides (FOS) are widely researched as prebiotics and immunostimulants in humans and terrestrial animals. However, limited researches on immune functions of FOS were reported in crustacean. In the present study, red swamp crayfish Procambarus clarkii were fed with different concentrations of FOS (2.0, 5.0, 8.0, 10.0 g kg^?1 diet), and then the immunostimulatory effects of FOS were evaluated by measuring immune parameters and examining immune‐related gene expression. PO and SOD activities were significantly increased in groups fed with 8.0 or 10.0 g kg^?1 of FOS compared with those in control group. In addition, significant elevations of SOD and phagocytic activities were also observed in group fed with 5.0 g kg^?1 of FOS. Among examined immune‐related genes, expressions of crustin1, lysozyme, SOD and pro‐PO were significantly up‐regulated by feeding with 8.0 or 10.0 g kg^?1 of dietary FOS. Survival rates of crayfish challenged with Aeromonas hydrophila were significantly improved by feeding with 5.0, 8.0 or 10.0 g kg^?1 of dietary FOS for 30 days. Phagocytic activities and bacterial clearance efficiencies were also significantly increased in groups fed with 8.0 or 10.0 g kg^?1 of FOS. The results indicated that dietary FOS effectively induced innate immune responses of red swamp crayfish in a dose‐dependent way and could be used as potential immunostimulant in crustacean.     

不同密度气泡幕对花骨和白甲鱼的阻拦效应

以贵州北盘江的花鱼骨（Hemibarbus maculates）和白甲鱼（Onychostoma sima）为研究对象,在矩形水槽中设置由气压为14.７ｋＰａ,孔距为1.0ｃｍ、2.５ｃｍ、4.０ｃｍ,孔径为1.0ｍｍ、1.５ｍｍ、2.０ｍｍ所组成的９组气泡幕密度,采用单因子试验法研究不同密度的气泡幕分别对花鱼骨和白甲鱼的阻拦效果。结果表明,９种密度的气泡幕对花鱼骨和白甲鱼均有一定的阻拦效果,其中花鱼骨在密度Ⅲ（孔距１.0ｃｍ、孔径２.0ｍｍ）时阻拦效果最好,阻拦率为 （９6.0０±2.65）％。白甲鱼在密度Ⅱ（孔距1.0ｃｍ、孔径1.5ｍｍ）时阻拦效果最好,阻拦率为（95.33±3.06）％。本研究可以为物理屏障拦鱼技术提供一定的理论和技术参考。     

Effects of nitrogen feeding for extraradical mycelium of Rhizophagus irregularis maize symbiosis incorporated with phosphorus availability

In terrestrial ecosystems, plants are frequently in symbiosis with arbuscular mycorrhizal fungi (AMF) with mineral nutrients and photosynthesis carbon exchanges in between. This research sought to identify the effects of phosphorus (P) levels on the nitrogen (N) uptake via extraradical mycelium (ERM) and the mycorrhizal growth response (MGR) of maize plants within the AMF symbiosis. Pots were separated into root compartments and hyphae compartments (HCs) with two layers of a 30‐μm mesh membrane and an air gap in between, where only hyphae could pass through, to avoid both N diffusion and root growth effects. Maize plants were inoculated with Rhizophagus irregularis with different N fertilization in HCs under two different P fertilization levels. Our results indicated that a strong increase in MGR with low‐P fertilization. The same tendency was not observed with high‐P fertilization, although both had a large increase in P concentration as a potential source of growth in shoot tissue of mycorrhizal plants. Substantial effects (10.5% more N) were observed in the case of high‐P availability for the host plants from ERM fed with N, whereas under low‐P conditions ERM may prioritize P uptake rather than N uptake. The AM fungi increase the uptake of N and P, which are most limiting in the soil with fewer forces from soil resources. In addition, there was still more P accumulated than N due to the high N for ERM with high‐P supply. Low N in HCs corresponded with a lower colonization rate in roots but with high hyphae density in HCs; this result suggest that N and P availability might change the ratio of extraradical to intraradical hyphae length.