红土坡地崩岗侵蚀过程与机理

崩岗是广泛发育于华南红色风化壳坡地上的各种崩陷地形，其危害性很大。按其形态特征可分为：条形崩网，叉（分支）形崩岗、瓢形崩岗、箕形崩岗和劣地崩岗等几种类型，其形态演变过程经历了前期的水蚀为主阶段，以及后期的重力侵蚀为主阶段，崩网的发生与下述几种情况有关：红土的机械组成特征，以及与水作用发生的变化；风化壳内的各种软弱结构面的存在；大暴雨触发作用以及各种地形要素的影响等。     

Aggregate Stability and Its Relationship with Some ChemicalProperties of Red Soils in Subtropical China

The stability of aggregates in the surface soil is crucial to soil erosion and runoff generation. Thus, to understand the stability and the breakdown mechanisms of soil aggregates as well as the relationship between aggregate stability and selected soil chemical properties, such as different forms of Fe and A1 oxides, organic matter, CEC and clay content, the aggregates of slightly and severely eroded red soils derived from Quaternary red clay in subtropical China were analyzed using the routine wet sieving and the Le Bissonnais methods. The results indicated that the aggregates of the severely eroded soils were more stable than those of the slightly eroded soils. Different aggregate breakdown mechanisms resulted in different particle size distribution. The slaking from entrapped air in aggregates severely destroyed the soil aggregates,especially in the slightly eroded soils. Meanwhile, mechanical breakdown and microcracking had little effect on the aggregates compared to slaking. The fragments resulting from slaking were mainly microaggregates that increased in size with increasing clay content. The main fragment size of the slightly eroded soils was 1.0-0.2 mm, while for the severely eroded soils it was 5.0-2.0 mm and 1.0-0.5 mm. Overall, more than 20% of the fragments were smaller than 0.2 mm.In addition, aggregate stability was positively and often significantly correlated with Fed, Ald, Feo and clay content, but significantly and negatively correlated to SOC.     

元谋干热河谷雨养型酸角对三种燥红土壤适应性研究

分析了元谋干热河谷旱坡地典型三种燥红土（普通燥红土，黄粉沙质燥红,变性燥红土）土壤的理化性状在三种土壤上种植的同龄，同品种酸角在同管理水平的条件下，其生长，产量，果实品质表现出明显的差异；普通燥红土质酸角生长量，产量，品质表现最好，黄粉沙质燥红土次之，变性燥红土最差，并通过对三种燥红土质退化程度分析研究，提出土壤侵蚀的退化酸角园整治措施。     

外燥对小鼠呼吸道分泌功能与抗体的影响

目的:观察外燥对小鼠呼吸道分泌功能(RS)与呼吸道IgG(IgG-R)的影响.方法:SPF级昆明小鼠72只随机分为4组:常温常湿组(A组)、常温燥组(B组)、温燥组(C组)和凉燥组(D组),每组18只.第7天与第14天检测各组RS(μg/mL)与IgG-R.结果:B组与D组第7天与第14天IgG-R高于A组(P＜0.05);C组第7天RS增高、第14天下降(P＜0.01),但IgG-R均低于其它3组(P＜0.05);D组RS第7天减少、第14天升高(P＜0.01).结论:温燥致病与致肺津生成障碍及气道御邪相关的IgG明显减少相关.温燥致气道IgG长期低水平现象值得研究.     

海南岛燥红土发生学特征的薄片观察

燥红土薄片的显微镜观察表明,由于长期受干热的生物气候条件影响,燥红土在发育过程中矿物风化淋溶程度较弱,各种分解形态的有机残体数量少,有机质含量缺乏。燥红土的主导形成过程是红化作用,由于遭受侵蚀,燥红土近代成土过程遭受砂化,表层呈现漂白砂型土壤微垒结。     

红土旱地冬小麦根系生长动态观测

冬小麦根系的生长发育可概括为根系的形成、壮大和逐渐衰亡三个阶段。初生根对根乃至小麦的整体生育具有奠基作用。     

水分胁迫对燥红土和变性土上玉米叶片过氧化物酶活性的影响

采用盆栽控制试验,研究了单作和混作栽培方式及不同施肥处理条件下,水分胁迫对金沙江干热河谷典型土壤(燥红土和变性土)玉米(Zea mays L.)叶片过氧化物酶(POD)活性的影响.结果表明①在一定的水分胁迫范围内,玉米叶片的过氧化物酶活性随着土壤含水量的降低而升高,但过度胁迫时,酶活性降低;②随着土壤含水量降低,燥土和变性土上生长的玉米叶片的酶活性的变化规律略有差异,这与二者的土壤物理性质有关;③施肥处理[T(N100 mg+P2O5*#170 mg+K2O 60 mg/kg干土);Z(NPK+Zn10 mg/kg干土);M(5.2 g干牛粪/kg干土+NPK)]和栽培方式对玉米叶片的酶活性有影响.     

微肥和有机肥对保山红土晒烟品质的影响

为研究中微肥和有机肥对红土晒烟外观和内在品质的影响,探索提高和改善红土晒烟品质的有效途径,试验在基肥中加入有机肥,和大田生长期在叶面喷施中微量元素肥料,结果表明:施用有机肥的处理与对照相比,产量增加7.3%￣20.9%,产值增加8.8%￣25.3%,以厩肥 菜籽饼处理的效果最好;四个喷施微肥的处理其产量和产值均超过了喷清水的对照,其中产量增加6.7%￣15.6%,产值增加6.8%￣20.5%,以喷施镁肥的增幅最大。另外,喷施硼肥的处理与对照相比,烟碱降低了29.5%,总糖提高了20.9%;施用有机肥的处理,上部叶总糖、还原糖、总氮和蛋白质含量比对照增加,但烟碱变化不大。因此,红土晒烟生产上控制在适宜用量范围内使用有机肥是可行的。此外,施用有机肥还使红土晒烟的评吸质量获得提高。在团棵期和旺长期喷施硼肥,掌握在适宜用量的范围不仅可有效降低红土晒烟的烟碱含量,使烟丝化学成分更趋协调,而且改善了红土晒烟的香气品质,使整体内在质量获得提高。     

从移栽期看红土晒烟的适生气候环境

为探索红土晒烟适宜的气候环境,设置不同的移栽时间,通过连续2年的试验,比较不同移栽时期烟株的生长发育情况和产量、品质表现,结果表明:红土晒烟大田生育期的低限温度和烤烟相近,移栽后生长前期日均温若低于18℃,产量将受到影响;大田生长中、后期日均温若低于20℃,对外观品质有不利影响.成熟调制期日均温应高于20℃,适宜温度是22℃～28℃左右.成熟调制期日照时数如少于210h,降雨超过30mm则可能对调制不利.