家蚕有色茧主要色素物质在幼虫体内的代谢变化

为探讨有色茧色素物质在蚕体内的代谢机制,检测了有色茧主要色素物质的含量及其在家蚕5龄幼虫不同时期中肠、血液、丝腺组织中的消长变化,分析色素物质从中肠进入血液再转运到丝腺的时序差异。有色茧中,黄茧的色素以类胡萝卜素化合物为主,绿茧的色素以黄酮类化合物为主。黄酮类化合物、类胡萝卜素化合物在家蚕5龄幼虫中肠、血液、中部丝腺、后部丝腺中的含量均呈现龄初低、龄末高的趋势,其中,黄酮类化合物在熟蚕组织中的含量是中肠>血液>中部丝腺>后部丝腺;类胡萝卜素化合物在熟蚕组织中的含量是中部丝腺>后部丝腺>中肠>血液。2种色素物质含量变幅最大的是后部丝腺组织,结黄茧蚕和结绿茧蚕的黄酮类化合物分别增加406.55%、202.50%,类胡萝卜素化合物分别增加211.80%、250.84%。黄酮类化合物在5龄幼虫丝腺组织的绝对含量是结绿茧蚕大于结黄茧蚕,类胡萝卜素化合物在5龄幼虫丝腺组织的绝对含量是结黄茧蚕显著大于结绿茧蚕,与在不同颜色蚕茧中检测到的2种色素物质含量一致。研究结果提示:黄酮类化合物在5龄幼虫中肠组织中积累较多,类胡萝卜素化合物在丝腺组织中积累较多;丝腺组织中2种色素物质的含量与茧色密切相关;来自桑叶中的2种色素物质经中肠消化吸收后,再通过血液进入丝腺组织并产生累积效应。     

花人同化 畅神乐生

道家的畅神自然审美观主张赏花人在清新自然的赏花审美环境中,动用五官和肺腑,全身心投入地与花融为一体,人的身心均获得了自然美的滋补、疗养与慰藉,实现了天人合一、花人合一的最高自然审美境界——这正是道家赏花审美所追求的在天地大化中寻求"畅神"的自由境界!道家在中国古代赏花审美实践中所体现出的以赏花审美为畅神之情、养生之艺、乐生之趣的民族花文化传统精华,理应继承借鉴并使之发扬光大。     

放牧率对绵羊体重及繁殖性能的影响

通过不同放牧率对内蒙古本地绵羊(母羊)连续2年(2008～2009)的体重和繁殖性能的影响的研究表明:(1)在试验期内,随着时间的推移,不同放牧率下的绵羊体重总体上都呈上升趋势;间隔1个放牧率或以上的处理间,存在不同程度的显著性差异;(2)绵羊的个体增重与放牧率之间存在负相关关系;而公顷增重与放牧率的关系符合二次曲线关系,在达到公顷最大增重前,随着放牧率的增大而增大,之后随着放牧率的增大减小;(3)单位家畜增重和单位面积增重的交点的生态学意义在于放牧率为1羊/hm2,公顷增重和家畜个体增重相同;单位家畜个体增重对应的畜产品最优放牧率为0.50羊/hm2,单位面积家畜最大增重对应的畜产品最优放牧率为2.38羊/hm2;(4)过高的放牧率导致绵羊出现空怀现象及产羔率下降;羔羊的初生重和个体增重均随着放牧率的增大而减小,但其显著性差异仅表现在较高的放牧率与较低的放牧率之间,而在相邻放牧率间差异不显著。     

成年母牛体况评分及其影响因素分析

体况评分(BCS)是评价奶牛饲养效果好坏、营养代谢正常与否的标志,也是奶牛健康与否的标志之一。体况评分为制订下一阶段的饲养管理措施提供重要依据,同时也受到很多因素的影响。本文旨在研究不同胎次、干奶期、泌乳期、不同的泌乳阶段等影响因素对奶牛体况评分的影响。测定本场2009年3月共219头胎次在0～6胎的中国荷斯坦奶牛体况评分,应用SPSS15.0软件对不同胎次、干奶期、泌乳期、不同的泌乳阶段等影响因素对奶牛体况评分的影响加以分析。结果表明:胎次对奶牛BCS的影响不显著(p0.05);干奶期和泌乳期对奶牛BCS的影响极显著(p0.01);泌乳阶段对BCS的影响极显著(p0.01)。因此提示在实际的生产中应灵活调控各影响因素对体况评分的影响,提高母牛生产性能。     

紫玉兰愈伤组织的诱导及胚状体获得试验研究

用正交统计方法,以MS为基本培养基,调节2,4-D、6-BA和NAA之间的配比,对紫玉兰的雌蕊、雄蕊、花被、花萼和带腋芽枝条等组织进行愈伤组织诱导,试验结果表明:雌蕊在MS+2,4-D 4.00 mg/L+6-BA 1.00 mg/L+NAA 4.00 mg/L能够产生浅黄绿色丝状愈伤组织;花萼在MS+2,4-D 4.00 mg/L+6-BA 1.00 mg/L+NAA 2.00 mg/L能够产生淡黄色块状愈伤组织;腋芽在MS+2,4-D 4.00 mg/L+6-BA 2.00mg/L+NAA 4.00 mg/L能够诱导产生浅绿色团状愈伤组织,该组织经转接培养后产生胚状体。     

Conversion of native forest to exotic Pinus radiata plantation: Response of understorey plant composition using a plant functional trait approach

This study aimed to determine the response of native plant species to changed growing conditions, especially increased shade, following establishment of exotic Pinus radiata plantation on cleared native eucalypt forest. In the Northern Hemisphere, species tolerant to shading are typically herbaceous perennials, with large seeds, no obvious mechanism of seed dispersal, and spread by clonal means. We investigated whether life form, mode of seed dispersal, leaf area, specific leaf area (SLA), nutrient uptake strategy, seed mass, fire response, plant height, and clonal spread differed between understorey species of pine plantation and native forest. Further, we asked whether plant functional traits that confer tolerance to stress through shading differ from those in other floras. The study was conducted on the Delatite Peninsula in north-eastern Victoria, Australia. Vegetation of adjacent native forest and pine plantation were surveyed using eight 7 m × 7 m plots per site, randomly located within five paired sites. Differences in plant traits between land-use types were tested by Non-metric Multi-dimensional Scaling (NMDS), analysis of similarity (ANOSIM) and paired t-tests. Cluster analysis of the nine plant traits was used to define emergent groups, with differences between land-use types examined by ANOSIM and indicator species analysis. There was a significant change in the composition of understorey vegetation following conversion to pine plantation that included a decline in the richness of native species. NMDS of plant attributes showed a clear separation of native forest from pine plantation with land use strongly correlated in ordination space (r² = 0.611). Cluster analysis produced seven emergent groups of plant functional traits for 78 identified plant species. Phanerophytes split into two groups (myrmecochorous trees and shrubs; myrmecochorous shrubs), perennial herbs into four groups (upright herbs, myrmecochorous herbs, barochorous herbs, flat rosette herbs) with one group representing therophytes and anemochorous perennials. Perennial herbs with intermediate SLA and clonal spread were tolerant of the shaded conditions in pine plantation while the two groups of phanerophytes and the myrmecochorous herbs were largely excluded. Shared traits of excluded emergent groups included those that provided an over-riding adaptation to mineral nutrient stress, including myrmecochory, low SLA, ectomycorrhizal and ericoid mycorrhizal associations and N₂-fixation. These plant traits could not provide tolerance to stress through shading, which is better explained by the open canopied nature of the native forest.     

Effects of auxiliary data source and inventory unit size on the efficiency of sample-based coarse woody debris inventory

The efficiency of a sample-based inventory can be greatly improved if lower cost information on the study area is utilized. It has been observed that the use of airborne laser scanning (ALS) data in the design phase may improve the efficiency of dead wood (coarse woody debris, CWD) volume inventory notably, i.e. a smaller standard error of the mean is observed with the same inventory costs. In the present case, several auxiliary data sources were employed in the design phase by using ‘probability proportional to size’ sampling to select the sample units to be inventoried in the field. It was observed that a combination of ALS data with either aerial photographs or stand-register data can improve the sampling efficiency even more than the use of ALS as a single data source. Since these additional data sources are often gathered for the inventory of living trees, their use does not incur extra expenses for CWD assessment. Thus, the use of these data separately or together with ALS data can greatly improve the cost-efficiency of a CWD volume inventory. It was also observed that the size of the sample units has a slight effect on the sampling efficiency. Even though the improvement in the sampling efficiency was usually greater with larger sample unit sizes, the CWD volume inventory was most efficient with moderate grid cell sizes.     

物探方法在地下异常体勘探的应用

通过对地质雷达探测数据的分析,找出地下异常体的范围,为设计部门提供能够选择合理的桥址的资料。     

血红铆钉菇生态学初步研究*

摘要：本研究通过调查北京延庆地区血红铆钉菇（Chroogomphis rutillus）的形态特征、子实体发生期、生态分布、及主要植被类群,并且测量该地区降水、空气温湿度和土壤含水量等生态因素,旨在掌握血红铆钉菇在野生条件下的基本生物学特性,为研究林菌共生机制、如何科学开发和利用野生血红铆钉菇资源及其半人工栽培打下了基础。研究表明：血红铆钉菇的子实体的主要发生期为每年八月中旬至九月下旬;子实体发生后第5d左右释放孢子;其子实体的干物质含量为12.3%。降水量与子实体发生关系最为密切。