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1.
调查了潜蝇在湛江市的发生与为害情况,结果表明,美洲斑潜蝇是为害作物潜蝇的优势种,包括有6个科18种,年间发生有6个为害高峰期。应用绿潜宝、乐果、巴丹等药剂在发生为害高峰期的峰前,中、后三次用药,防治效果维持70%以上。  相似文献   

2.
用五点法进行抽样调查并探讨了湿地松粉蚧(Oracella acuta Lobdell)侵入后,湿地松(Pinuselliotii)新植树皮化学成分与粉蚧为害的关系。结果表明:均衡、协调的营养对粉蚧生长和繁殖有利;粉蚧为害主要导致新梢树皮蛋白质、粗灰分含量明显增加,还原糖含量明显减少;粉蚧发生高峰期,新梢树皮蛋白质含量与与粉蚧虫口密度呈显著正相关。  相似文献   

3.
用五点法进行抽样调查并探讨了湿地松粉蚧(Oracella acuta Lobdell)侵入后,湿地松(Pinus elliotii)新植树皮化学成分与粉蚧为害的关系。结果表明:均衡、协调的营养对粉蚧生长和繁殖有利;粉蚧为害主要导致新梢树皮蛋白质、粗灰分含量明显增加,还原糖含量明显减少;粉蚧发生高峰期,新梢树皮蛋白质含量与与粉蚧虫口密度呈显著正相关。  相似文献   

4.
市县动态     
《浙江国土资源》2011,(7):61-64
临安市国土资源巡查"触觉"更灵敏春夏季是农村建房高峰期,总有一些人无视法规闯"红线",占用耕地、未经审批私自建房。近日从临安市国土资源局於潜国土资源中心所获悉,往年这个时候,该所都会接到不少有关违章违规违法建房的举报电话,而今年4月以来,这样的电话明显少了很多。据了解,今年该所多了一支队伍——国土资源巡查队於潜片  相似文献   

5.
春夏季是农村建房高峰期,总有一些人无视法规闯"红线",占用耕地、未经审批私自建房。近日从临安市国土资源局於潜国土资源中心所获悉,往年这个时候,该所都会接到不少有关违章违规违法建房的举报电话,而今年4月以来,这样的电话明显少了很多。  相似文献   

6.
应用数诸天气学的方法,对风湿病发生时的气象条件和天气系统进行分析归纳,得出成都地区风湿发生的高峰期主要是春末夏初,秋末冬初,风湿的发生主要与气象因子中的相对湿度,温度及其变化有很大的关系。成都地区与风湿发作的有关天气系统有西南低涡、南支槽、蒙古高压、高原低涡、高原切变线等,且在冷锋过境或持续低温阴雨的天气形势下会诱发风湿病发作,由此可通过数据统计的方法和天气学的方法来预测风湿病发病期,为预防风湿病提供依据。  相似文献   

7.
前文对湛江港浮游硅藻的种类组成和周年的数量变化已作了论述。本文主要论述从1981年4月至1982年3月湛江港浮游硅藻优势种的初步调查,鉴定结果共有9种。调查水域浮游硅藻优势种年总生物量的周年变化中,大约出现三个高峰期。在9个优势种中.它们生物量的周年变化皆不相同。调查结果表明,湛江港浮游硅藻总生物量的多少是由优势种总生物量的多少决定的。  相似文献   

8.
东营市基岩地质背景与地热资源分布   总被引:1,自引:0,他引:1       下载免费PDF全文
东营市地热资源丰富,地热分布受储盖条件及基岩构造背景等因素制约,热水储层为多层结构系统。在一定深度范围内,地温总体呈高、低相间的带状展布。其平面展布,相对高温区与基岩潜凸区一致,相对低温区与基岩潜凹区一致。地热主要为正常增温传导型,在潜凸与潜凹结合部位,可能存在水热对流型。  相似文献   

9.
对雷州半岛旱地蔗田杂草进行2a的调查,结果表明,全年共有18科48种杂草相继发生为害,以禾本科、菊科、莎草科和苋科为主。并经过杂草防除试验,分析了除草剂的使用方法。  相似文献   

10.
对雷州半岛旱地蔗田杂草进行2a的调查,结果表明,全年共有18科48种杂草相继发生为害,以禾本科、菊科、莎草科和苋科为主,并经过杂草防除分析了除草剂的使用方法。  相似文献   

11.
The pigments in Laminariajaponica was extracted with six organic solvents and analyzed in spectroscopy analysis. The extractions conditions were screened by an orthogonal test and the quantity of extracted pigments was determined spectroscopically. The results show that: (1) among the six organic solvents, acetone was the most effective one for the extraction; (2) the optimum extraction conditions were as follows: the ratio of S/M (solvent volume/ material weight) was 30 ml/g; fresh seaweed was extracted 2 times in 2 h; (3) the average total content of pigments was 1.85 mg/g (calculated with dry L. japonica).  相似文献   

12.
We used standard periphyton samplers to examine the colonization pattern of periphytic algae on artificial substrates (glass slides) in Lam Tsuen River, Hong Kong, in dry (winter) and wet (summer) seasons. In each season, six replicated slides were retrieved randomly and replaced by new slides at weekly intervals over a period of 6 weeks. We thus obtained two batches of slides, both with a series of different exposure times (1 to 6 weeks): one batch was set up at the same time (start of the sampling) and the other was harvested at the same time (end of the sampling). Changes in taxonomic composition, species diversity (Shannon-Wiener diversity index), standing crop (in terms of cell density and cell biovolume), and abundance of the abundant algal species were monitored and compared between the two batches of slides. The succession patterns of the periphytic algae were similar between the two batches in each season, while more remarkable differences were observed between the two seasons, suggesting that either batch would be suitable for a colonization study of periphytic algae. The cell density was dominated by diatoms in both seasons, while the cell biovolume was dominated by diatoms in winter and by green algae in summer. The cell density and biovolume attributed to blue green algae was relatively small. Most of the diatom species exhibited similar colonization patterns throughout the experiment, while green algae showed different succession patterns in different seasons or sampling methods, indicating that diatoms are better bio-indicators than green algae for a periphyton colonization study. In general, the diversity indices and the standing crops reached their maximums at around week 4, and they were higher in summer than in winter.  相似文献   

13.
In the Wenchuan Earthquake area,many co-seismic landslides formed blocking-dams in debris flow channels. This blocking and bursting of landslide dams amplifies the debris flow scale and results in severe catastrophes. The catastrophic debris flow that occurred in Qipan gully(Wenchuan,Southwest China) on July 11,2013 was caused by intense rainfall and upstream cascading bursting of landslide dams. To gain an understanding of the processes of dam bursting and subsequent debris flow scale amplification effect,we attempted to estimate the bursting debris flow peak discharges along the main gully and analyzed the scale amplification process. The results showed that the antecedent and triggering rainfalls for 11 July debris flow event were 88.0 mm and 21.6 mm,respectively. The event highlights the fact that lower rainfall intensity can trigger debris flows after the earthquake. Calculations of the debris flow peak discharge showed that the peak discharges after the dams-bursting were 1.17–1.69 times greater than the upstream peak discharge. The peak discharge at the gully outlet reached 2553 m~3/s which was amplified by 4.76 times in comparison with the initial peak discharge in the upstream. To mitigate debris flow disasters,a new drainage channel with a trapezoidal V-shaped cross section was proposed. The characteristic lengths(h1 and h2) under optimal hydraulic conditions were calculated as 4.50 m and 0.90 m,respectively.  相似文献   

14.
The upper Yangtze River region is one of the most frequent debris flow areas in China. The study area contains a cascade of six large hydropower stations located along the river with total capacity of more than 70 million kilowatts. The purpose of the study was to determine potential and dynamic differences in debris flow susceptibility and intensity with regard to seasonal monsoon events. We analyzed this region’s debris flow history by examining the effective peak acceleration of antecedent earthquakes, the impacts of antecedent droughts, the combined effects of earthquakes and droughts, with regard to topography, precipitation, and loose solid material conditions. Based on these factors, we developed a debris flow susceptibility map. Results indicate that the entire debris flow susceptibility area is 167,500 km2, of which 26,800 km2 falls within the high susceptibility area, with 60,900 km2 in medium and 79,800 km2 are in low susceptibility areas. Three of the six large hydropower stations are located within the areas with high risk of debris flows. The synthetic zonation map of debris flow susceptibility for the study area corresponds with both the investigation data and actual distribution of debris flows. The results of debris flow susceptibility provide base-line data for mitigating, assessing, controlling and monitoring of debris flows hazards.  相似文献   

15.
计算内蒙古测震台网2019-12~2020-11山洞观测数据的加速度功率谱密度(PSD)和相应的概率密度函数(PDF),研究相应台站的背景噪声特征。结果表明,高频段背景噪声的昼夜差异显著,疫情防控期间噪声水平明显低于其他时段;次级微震频段背景噪声季节性变化显著,噪声水平冬季强、夏季弱,随着台站离海岸线距离增大,PSD峰值有逐渐减小的趋势;主微震频段背景噪声在10~20 s均有峰值,峰值冬季最强,春、夏、秋季基本没有差异,不同台站同一季节峰值差异小;长周期段噪声水平四季差异不大,春、夏季略高于秋、冬季。  相似文献   

16.
【目的】研究马尾藻及其油页岩混合物在不同温度下的热解产气特性。【方法】利用燃烧烟气污染物测试实验台,测量马尾藻及其油页岩混合物在温度区间400℃至800℃下CO和H_2的排放特性,包括峰值浓度、峰值时间和平均浓度。【结果】马尾藻以及其油页岩混合物的热解过程可分为慢速析出、快速析出和降速三个阶段。马尾藻单独热解实验中,排放的CO体积分数峰值达到10 367×10~(-6)。温度的升高有利于马尾藻在热解中CO和H_2的析出,反应的开始时间和完成时间均有所提前。在马尾藻与油页岩混合物的热解中,H2的析出在700℃时达到最高(体积分数峰值为1 254×10~(-6))。油页岩的加入迟滞了CO和H_2的排放时间。【结论】油页岩的加入有效减少马尾藻热解过程中CO的排放并缩短反应时间,提高效率节省能源,马尾藻与油页岩的混合热解具有良好的应用前景。  相似文献   

17.
2019-06-17四川省宜宾市长宁县6.0级地震后,双河镇布设了多个地震监测仪器,以获取不同场地条件下的地震动相关参数.研究结果表明:1)在同一介质下,60 m高程对地震动的峰值加速度放大可达1~3倍,阿里亚斯强度放大可达2~5倍,同时微地貌的不同可使放大效应具有一定的方向优势;2)在同一高程不同介质条件下,相较于砂...  相似文献   

18.
近些年来,空间数据获取技术得到了迅猛的提高,例如LIDAR,通常可以产生成千上万个点,这对计算机的处理能力提出了挑战.最近,图形处理器(GPU)的计算能力得到了巨大的提升,致使GPU的通用计算引起了关注.GPU是流处理器的集合,最近的设备的流处理器超过240个,浮点峰值比CPU快10多倍.在GPU上编程和编译的环境称计...  相似文献   

19.
I.INTRODUCTIONUptothepresent,severaltheoreticalandimportantpracticalproblemshavebeensolvedinkarstgeomorphology.However,alongw...  相似文献   

20.
随着旅游者对休闲娱乐类旅游需求的不断增加,山地型旅游区已成为最受欢迎的旅游目的地之一,利用新兴且高效的轨迹记录方式挖掘山地型旅游区游客在小尺度范围内动态的时空行为特征和制约因素,对旅游区线路设计和旅游产品优化尤为重要,也将为山地型旅游区的深化发展和科学管理提供建议。本文以湖北省恩施州恩施大峡谷为案例地,基于“六只脚”平台的GNSS轨迹及位置照片数据,结合GIS在线地图绘制的景区路网和从BigMap平台获取的POI数据,选择GNSS轨迹栅格化的概念模式解析出恩施大峡谷游客轨迹的时空行为特征,尝试探讨与其他类别旅游区时空行为特征的差异,从而总结出山地型旅游区的行为特征,并通过网络点评数据和游记文本等网络文本挖掘行为特征形成的影响因素。研究表明:(1)月份和季相层面,游客行为5月游客量处于峰值,节日效应明显,短假期效应较强;淡旺季游客行为轨迹呈非集聚性,旺季游客量主要受气候条件影响呈不稳定态势;(2)游客行为轨迹于11:00—14:00游客量达到顶峰,日内结束时间相对较早,且兴趣点选择偏向知名度高的七星寨景区;(3)空间分布特征层面,受时空因素控制,单一路径景区轨迹集中度较强;(4)不同性别...  相似文献   

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