影响广东省石灰岩地区造林成活率的因素分析

石灰岩地区造林成活率低导致多年造林不见林 ,严重阻碍石灰岩地区绿化进程和经济发展。对石灰岩地区造林绿化现状调查 ,运用全面质量管理的理论和原理 ,采用PDCA循环工作法 ,分析导致石灰岩地区造林成活率低的各种因素 ,并提出对策措施。     

电动凿岩机运行质量评估仪的软件设计方法

“电动凿岩机运行质量评估仪”是一种用来对正在运行的电动凿岩机的动态质量指标进行评估的仪器。被评估的电动凿岩机质量指标包括空载／负载工作电流／电压、振动频率、冲击力及转速率等。本文介绍了一种利用微机实现上述质量评估过程的ＤＡＣＳ软件设计方法，并讨论了关键的设计原理和实现技术。     

A relatively simple scaling method for describing the unsaturated hydraulic functions of stony soils

Few if any methods exist to estimate the effects of stone content (stoniness) on the unsaturated soil hydraulic properties. A relatively simple scaling method is presented to estimate the hydraulic conductivity of unsaturated stony soils having different stone contents. A key assumption of the method is that van Genuchten's water retention parameters α and n of the fine soil fraction are the same as those of the stony soil. The method further assumes a linearly decreasing relationship between the saturated hydraulic conductivity and the stone content, based on previous numerical simulations. Using the proposed method, it is possible to calculate the hydraulic conductivity of unsaturated stony soils, knowing the saturated hydraulic conductivity of the fine soil fraction, the retention curve of the fine soil fraction, and the particular stoniness of the soil.     

几种磷矿粉中磷和钙溶出动力学特性

采用间歇实验方法,研究4种磷矿粉在1M NH4OAc(pH4.8)酸性溶液中磷和钙溶出动力学规律,结果表明:磷矿粉中磷的溶出分为2个阶段,0～30min为快反应过程,30min后为慢反应过程,它能较好地符合Elvoich方程,磷的溶出速率(b)与枸溶性磷含量有较好的相关性,主要受磷矿粉中SiO2和碳酸钙含量的影响,枸溶性磷含量愈高,磷的溶出速率愈大,溶出磷的浓度也愈高。磷矿粉中钙的溶出也符合Elvoich方程,且与游离的碳酸钙含量有关,与其他磷矿粉不同,在PR1中钙的溶出浓度较高,很可能来自于碳酸钙的溶解。因而,磷矿粉不仅可以提供磷素营养,还提供植物生长所需的钙素营养。     

水稻叶绿体表达体系的建立及抗PPT叶绿体转化植株的获得

 【目的】建立外源基因在水稻叶绿体中的表达体系。【方法】通过分析已公布的水稻叶绿体基因组全序列及其基因分布特点，选择ndhF与trnL的基因间序列作为除草剂PPT抗性基因bar定点整合的位点。以水稻叶绿体基因组DNA为模板，采用PCR方法克隆了两个适于水稻叶绿体基因组遗传转化的同源片段，构建了含水稻叶绿体16S高效表达启动子、外源基因bar、psbA基因的3′序列（终止子）以及两个同源片段的水稻叶绿体特异表达载体pRB。【结果】采用基因枪法转化水稻品种中花10号幼穗诱导的愈伤组织，并再生植株，获得转化体后代种子。对转化植株进行的分子检测结果表明，外源基因bar 可能被整合到水稻叶绿体基因组中。后代种子的遗传学分析显示，外源基因bar可正常表达并遗传。【结论】利用所建立的水稻叶绿体外源基因表达体系，外源基因bar既可在水稻叶绿体基因组中正常表达，还可作为转化体筛选时的除草剂抗性选择标记。     

Spatial distribution of rock fragments in dolines: A case study in a semiarid Mediterranean mountain-range (Sierra de Gádor, SE Spain)

Rock fragments (RFs) at the soil surface have great effects on the intensity of various hydrologic and geomorphic processes. However, little information is available on the spatial distribution of rock fragments (RF) in the dolines, which may be of importance in understanding overland flow and subsequent recharge in limestone karst landscapes. This study analysed spatial variability of RF cover and size in different topographic positions (top, upper, middle and lower position) in three dolines in Sierra de Gádor (Almería province, south-east Spain). The results indicated that cover percentage of small RFs (5–20 mm) increased but large RF cover (250–600 mm and > 600 mm) decreased from the upper position to the lower position of the dolines. Small RFs were usually resting on the soil surface while most large RFs tended to be partly embedded in the soil surface. Total RF cover and D₅₀ (median diameter) of the surface RFs greater than 5 mm tended to increase with slope gradient.     

秘鲁番茄与栽培番茄回交一代的获得及其染 色体片段分析

以栽培番茄1052 为母本,以秘鲁番茄LA3858 为父本进行杂交,通过幼胚挽救培养获得了1
株F1 植株,再以栽培番茄1052 为母本进行回交,通过幼胚挽救获得了6 株BC1 单株,利用129 个分布于
12 条染色体上的CAPS、SSR 和InDel 标记对BC1 单株进行染色体片段分析,结果表明6 株BC1 单株中12
条染色体含有的秘鲁番茄片段涵盖了秘鲁番茄LA3858 的整个基因组。     

Potato virus X (PVX) resistance in tomato cultivars

Understanding how birds detect and react to deterrent methods which are employed to protect structures is important both for the effective control of property damage, and to ensure that human health and safety are not compromised. One such device is a shock strip that causes slight pain to birds when they use a perch. Our aims were to determine: (1) the efficacy of a shock strip to flocks of Brown-headed Cowbirds (Molothrus ater), and Rock Pigeons (Columba livia); (2) the length of time to extinction of effect; (3) whether members of a flock show a behavioural response to treatment; and (4) whether the birds habituate to the treatment. When activated, shock strips were effective in displacing birds from treated areas. Birds had to experience the treatment; there was no discernible indication of flock members reacting to affected birds. When strips were deactivated after an initial period of activation, birds required more than 2 hours to return to treated areas. No habituation was observed. Because birds had to experience the shock, reduced coverage of a structure or use of sham devices to lower costs is considered inadvisable.     

Effect of shale fragments on alfalfa growth under controlled conditions

Abstract

The effect of shale fragments as soil conditioner was investigated in two greenhouse experiments using alfalfa as the test plant. Four soils differing by the texture and the shale content were used, the < 2 mm material alone or in a mixture with coarser fragments, shale or gravel. In the first experiment, cuts 1–4 were taken under adequate watering before water stress was applied for cuts 5–8. Water stress was applied since the beginning in the second experiment.

Soil‐shale substrates generally produced the highest yields. Soil‐gravel substrates followed next in the first experiment but sustained generally the lowest yield in the second experiment.

The results were related to the effect of the coarse fragments on soil structure and water retention of the substrates.     

珊瑚菜叶绿体基因TrnV－M序列的PCR扩增与分析

[目的]对珊瑚菜TrnV-M基因片段PCR扩增条件进行优化和测序分析,为濒危物种珊瑚菜的种质资源保护和遗传多样性研究提供理论依据。[方法]探索并优化珊瑚菜叶绿体基因片段TrnV-M的PCR扩增条件,并对扩增产物进行测序分析。[结果]珊瑚菜TrnV-M基因片段的PCR最佳反应体系:d NTPs 0.50μL,Buffer 2.50μL,Trn M 1.25μL,TrnV 1.25μL,DNA 1.00μL,r Taq E 0.15μL,dd H2O 18.35μL,总体积25.00μL。最佳扩增程序:94℃预变性3.0 min;94℃变性50 s,58℃退火45 s,72℃延伸1 min 25 s,38个循环;72℃延伸8 min。[结论]在最优体系下获得了清晰、稳定的目的条带,校正后条带长度约为757 bp,通过Gen Bank的BLAST比对,确定为TrnV-M基因片段。