三维激光扫描技术在淤地坝安全监测中的应用

[目的]监测黄土高原丘陵地区淤地坝在运行中的缓慢和微小变化,及时发现淤地坝的病险隐患,为科学监测、评价陇中黄土丘陵沟壑区乃至西北黄土高原地区淤地坝安全运行提供依据。[方法]通过Nove MS 50全站扫描仪对南湾骨干坝和别杜川骨干坝坝体沉降、水平移位及坝体表面侵蚀进行定期激光扫描,利用等间隔的点云记录坝体和库岸不规则形态。[结果]两期监测对比可以看出,南湾骨干坝接近路面的部分有约1cm的变化,左侧库岸有明显的变化,变化量约为0.8cm,日后极有可能会发生小规模坍塌。别杜川骨干坝整个堤坝在半年的时间内右侧部分约有1~2cm的下降变化,监测结果和管理部门常规监测变形结果一致。[结论]将三维激光扫描技术应用于淤地坝变形监测,可以及时、准确、全面、直观获取淤地坝坝体和库岸表面数据,使得变形监测工作更加全面、便捷、可信。     

Corn Monoculture Yield Response to Fertilization and Nitrate Nitrogen Distribution

The objectives of this study were to determine the effects of fertilization system, nitrate (NO₃)– nitrogen (N) distribution along soil profile, and their interaction on corn yield. The study was conducted at the experimental field of Institute of Field and Vegetable Crops in Novi Sad (Serbia) during 2001–2004. Corn monoculture included four fertilization variants: control (Ø), nitrogen–phosphorus–potassium (NPK) mineral fertilizers, mineral fertilizer + corn stalks (NPK + S), and mineral fertilizers + manure (NPK + M). The greatest yield was found in the variant NPK + M (9.25 t ha^?1). Path coefficients showed that greatest direct positive effects on corn yield were exhibited by NO₃-N levels at soil depths of 60–90 cm and 30–60 cm. The path analysis showed that winter precipitation (WP) had a direct negative effect on yield performance. However, the effect of the downward movement of NO₃-N from the topsoil to deeper soil layers of WP on yield was positive.     

Changes of stomatal parameters of four typical species in the Loess Plateau of China over the last century

Abstract

The variation and correlations of the stomatal densities, lengths, widths, areas in four C₃ species of the Loess Plateau from 1930s to 2002 were studied. The response of stomatal density to climatic change differed among the four species. Over the years from 1930s to 2002, the stomatal density did not change in Quercus liaotungensis, rising only by 1.32%, and slightly decreased by 9.79% in Ostryopsis davidiana. However, the stomatal density decreased significantly by 27.86% and 46.85% in Zizyphus jujuba var. spinosa and Sophora viciifolia, respectively. The influences of climatic change on other stomatal parameters were also species-specific. The stomatal length, width, and area varied more significantly in Zizyphus jujuba var. spinosa than in Quercus liaotungensis and Ostryopsis davidiana over the last century. The correlation analysis among the stomatal parameters of the three species showed that there were positive correlations among the stomatal length, width and area, but there were negative correlations between the stomatal length, width, area and density.     

Analysis of NO3 interception of the parasitic angiosperm Orobanche spp. using a positron-emitting tracer imaging system and 13NO− 3: A new method for the visualization and quantitative analysis of the NO3 interception ratio

Abstract

The root parasitic plants Orobanche spp. (broomrapes) seriously affect agricultural production. A visualization and quantitative analytical method for the interception of nutrients was established using a positron-emitting tracer imaging system and ¹³NO^? ₃. By using this analytical method that involves volume normalization with ¹⁸F^? images, the nitrogen nutrient interception ratio of the Orobanche spp. was calculated to be 73.6 ± 3.9% in a host–parasite system of red clover (Trifolium pratense L.).     

Inheritance of Aluminum Tolerance and its Effects on Grain Yield and Grain Quality in Oats (Avena Sativa L.)

Summary Aluminum toxicity due to the cation Al⁺³ is a major factor limiting yields in acid soils. Wide genetic variability to aluminum tolerance is found in oat genotypes. The objectives of this study were to determine the number of genes controlling aluminum tolerance in oats and to verify if any detrimental effects were present of the aluminum tolerance genes on grain yield and grain quality in Al⁺³free soils. Aluminum tolerance was estimated as the average regrowth of the main root after exposure to toxic levels of Al⁺³ in a hydroponic solution under controlled conditions. The number of genes controlling that trait was estimated from the distribution of the average root regrowth frequencies in a population of 333 recombinant inbred lines (RIL's) in generations F_5:6 and F_5:7. The effects on grain yield and grain quality were assessed in a subpopulation of 162 RIL's chosen based on their aluminum tolerance response. Aluminum tolerance in the evaluated population was controlled by one dominant major gene with the tolerant genotypes carying Al _a Al _a and the sensitive ones al _a al _a alleles. No detrimental effects of the Al _a allele on grain yield or grain quality were detected.Part of the Master of Science dissertation of the first author     

Numerical Analysis on Stability of Rock in Sijiaotian Tunnel

The Sijiaotian Tunnel in Yunnan Dabao Highway lies in the narrow defile landscape,and the engineering geology condition is complex,with plenty of cienega.According to the actual situation of the Sijiaotian Tunnel Project in Yunnan Dabao Highway,the stability of the surrounding rock mass is studied by using a 3-D non-linear FEM.The Drucker-Prager criterion is chosen as the failure criterion of the rock.The relatively dangerous zone and the monitoring points in the tunnel are determined.The numerical results show that the Sijiaotian Tunnel is relatively stable.The conclusion has some significance for guiding the construction of similar projects.     

利用相同来源F2:3和BC2S1群体定位玉米生育期QTL

以普通玉米自交系丹232和爆裂玉米自交系N04为亲本构建259个F2:3和220个BC2S1家系群体,利用SSR标记构建分子标记遗传图谱,利用复合区间作图方法对4个生育期性状进行QTL定位和效应分析。利用F2:3群体共检测到4个抽雄期QTL、6个吐丝期QTL和3个散粉期QTL。单个QTL可解释的表型变异为6.7%~18.4%,可解释的表型总变异为28.9%~50.3%,11个QTL的增效基因来自生育期较长的亲本丹232,其余2个QTL的增效基因来自生育期较短的亲本N04;BC2S1群体检测到8个与4个生育期性状相关的QTL,单个QTL可解释的表型变异为4.5%~11.6%,可解释的表型总变异为13.2%~18.5%,增效基因来自两个亲本的QTL为3个和5个。两类群体检测出QTL的数目、位置、效应和贡献率均存在较大差异,主要原因在于BC2S1群体抽样选择所引起的群体结构差异,F2:3群体显示出较高的QTL检测能力,但回交育种过程中应慎重依据F2:3群体QTL定位结果进行标记辅助选择(MAS)。     

莴苣花叶病毒北京分离物基因组3′末端序列分析

笔者通过RT-PCR方法对LMV北京分离物（LMV-BJ）基因组3＇端1620nt的核苷酸片段进行了克隆和序列分析（GenBank登录号为EF423619）。所获片段含有NIb基因3＇端的574nt,编码NIb C-端190个氨基酸;完整的CP基因,全长为834nt,编码一个由277个氨基酸组成的分子量约为30kDa的结构蛋白;3＇非编码区含有209nt。通过序列分析软件将LMV-BJ与已经报道的法国分离物O（X97704）、法国分离物E（X97705）,美国分离物（X65652）,巴西分离物（AJ278854）和余杭分离物（AJ306288）基因组3＇末端和CP基因的核苷酸序列与氨基酸序列分别进行了比较。     

GA1,3,4,7酶联免疫检测法（ELISA）的建立

用碳二亚胺法将赤霉素Ａ４与卵清蛋白连接，形成ＧＡ４－ＯＶＡ复合物用于包板，利用ＧＡ４－Ｍｅ与ＧＡ４－０ＶＡ对兔抗ＧＡ４－ＰＡｂｓ竞争结合反应，建立了ＧＡ１，３，４，７间接酶闻免疫检测法。其灵敏度，检测范围和最小检测样品量分别为４５ｐｇ，０．２－２００ｎｇ和５０－５００ｍｇ，样品的平均回收率为９７％，批内和批间的变异系数分别为４．２％和４．８％。     

Effects of elevated carbon dioxide and ozone on potato tuber quality in the European multiple-site experiment ‘CHIP-project’

Potato (Solanum tuberosum L cv. Bintje) was exposed to ambient and elevated carbon dioxide (CO₂), to ambient and elevated ozone (O₃) and to elevated levels of both gases during two growing seasons, 1998 and 1999. Experiments in open-top chambers (OTC) were carried out in Finland, Sweden, Ireland, United Kingdom, Germany and Belgium and a FACE (Free Air Carbon dioxide Enrichment) experiment was carried out in Italy. In OTCs the plants were grown under ambient CO₂ concentrations or with 550 and 680 μl l⁻¹ CO₂ alone or in combination with ambient or elevated O₃ concentrations (target seasonal mean of 60 nl l⁻¹ 8 h per day). In the FACE systems the plants were exposed to ambient or 550 μl l⁻¹ CO₂. In the OTC experiments the reducing sugar content of potato tubers decreased significantly with increased concentration of O₃. The starch content of potato tubers decreased, with negative impact on tuber quality, but the ascorbic acid concentration increased as a function of the AOT40 (The sum of the differences between hourly ozone concentration and 40 nl l⁻¹ for each hour when the concentration exceeds 40 nl l⁻¹ during a relevant growing season). However, simultaneous exposure to elevated CO₂ counteracted the ozone effect. With increase in the CO₂ exposure, glycoalkaloid and nitrate concentrations decreased yielding improved quality, while the citric acid concentration decreased causing a higher risk for discoloration after cooking. The amount of dry matter and starch increased significantly in the FACE experiment.