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1.
内吸杀菌剂根系打浆防治松针褐斑病   总被引:3,自引:0,他引:3  
湿地松或火炬松1年生苗,用一定浓度多菌灵或甲基托布津泥浆根系打浆处理,然后定植于苗圃中。30~50天后接种松针褐斑病菌(Lecanosticta acicola),又经50天左右检查感病情况;或将处理苗定植于发病林地上,任其自然发病,每年检查感病情况,共2~3年。所有杀菌剂处理浓度,在短期或1年内均可显著降低松针褐斑病的侵染,当年松苗感病程度与杀菌剂处理浓度没有明显相关性。但第2年或第3年,松苗感病程度随时间而增加,且与杀菌剂处理浓度呈明显负相关。结果表明,松苗定植前用含有效成分3%~5%多菌灵或含有效成分5%~10%甲基托布津泥浆处理根部,可在2~3年内有效地防止松针褐斑病的侵染。  相似文献   

2.
1松针饲料添加剂的生产松针饲料添加剂,又称松外粉饲料,是一种富含维生素和微量元素的畜禽补充饲料。特级品中含胡萝卜素90ghe以上,含微量元素有锌、硒、铁、锰、铜、钻、钢等,钙和磷的含量也较高,并含有畜禽需要的绝大部分的氨基酸。因此制成配合饲料用以喂养畜禽,具有抗疾病、增重快、产蛋产奶多的作用。一般在猪饲料中添加25%~4.5%的松针粉,增重率能提高15%~40%,并提高瘦肉率;在蛋鸡饲料中添加5%松外粉,产蛋率可提高13%以上;在奶牛饲料中添加Ic%松针粉,产奶量可提高4.5%~74%。此饲料是由松林抚育和采伐时产生…  相似文献   

3.
目的:建立HPLC法测定云南松松针中莽草酸含量的方法.方法:采用Phenomenex Gemi-ni-NX 5μC18110A(4.6mm×250mm)色谱柱,以甲醇∶1%磷酸水溶液(15∶85)为流动相,检测波长215nm,流速1mL/min,柱温为30℃.结果:莽草酸进样量在0.101 2~2.024μg范围内线性关系良好(r=0.999 7),样品的平均回收率为99.76%,RSD为0.89%(n=9).结论:本法操作简便、快速、分离效果好、稳定性高、重现性好,可用于松针中莽草酸的含量测定.  相似文献   

4.
降雨和坡度对路基边坡产流产沙的影响   总被引:4,自引:0,他引:4  
【目的】分析降雨和坡度对铁路路基边坡产流产沙的影响,为胶东半岛区域铁路建设过程中路基区水土流失监测及防治提供技术支撑。【方法】采用人工模拟降雨试验,在3种雨强(20、40、60 mm/h)、2个坡度(30°、35°)模拟条件下,研究降雨、坡度对胶东铁路路基边坡产流产沙的影响。【结果】模拟降雨条件下,当降雨强度由20 mm/h增加到60 mm/h,相同坡度下的路基边坡产流起始时间缩短56~73 s; 当坡度由30°增大到35°,相同雨强下的路基边坡产流起始时间提前2~23s。径流量、产沙率在降雨初期剧增到峰值,之后径流量逐渐趋于稳定,而产沙率波动减小后逐渐趋于稳定。相同坡度条件下,雨强由20 mm/h增加到40 mm/h,径流量和产沙率分别增加37.8%~115.2%和67.0%~86.9%; 雨强由40 mm/h 增加到60 mm/h,径流量和产沙率分别增加54.7%~125.0%和144.5%~177.9%。相同雨强条件下,坡度30°~35°处于对径流侵蚀影响的临界坡度范围内,坡度对径流量、产沙率的影响较复杂,小雨强(20、40 mm/h)时,坡度是主要影响因素,35°边坡径流量、产沙率小于30°边坡; 大雨强(60 mm/h)时,降雨成为主要影响因素,35°边坡径流量大于30°边坡,而产沙率小于30°边坡。【结论】降雨、坡度对胶东铁路路基边坡产流起始时间、径流量、产沙率等有一定的影响,模拟降雨条件下,雨强和坡度的增加将缩短产流开始时间,尤以雨强的影响更加明显。  相似文献   

5.
以室内试验槽为平台,利用人工模拟降雨试验,定量分析了坡度为5°时,在30mm/h,60mm/h和120mm/h降雨强度下,有大孔隙试验槽和无大孔隙试验槽坡面流的水动力学参数的异同点.结果表明,各场次降雨的两坡面流的流态均为层流,除降雨强度为30mm/h时,无大孔隙坡面的坡面流为急流外,其他场次的水流均为缓流;在同一降雨强度下,相对于无大孔隙坡面,有大孔隙坡面的坡面流流速、单宽流量、弗劳德数和雷诺数较小,径流深、径流切应力、水流运动阻力以及坡面糙率较大;随着降雨强度的增大,两坡面的径流深和单宽流量增加,坡面流流速、径流切应力和雷诺数均增大,阻力系数和曼宁糙率均呈现先增大后减小的趋势,弗劳德数则呈现先减小后增大的趋势.  相似文献   

6.
白三叶草褐纹斑病病原菌生物学特性研究   总被引:2,自引:0,他引:2  
从白三叶草褐纹斑病叶片上分离纯化得到病原菌束状匍柄霉[Stemphylium sarcinifoDne(Car.)Wiltsh.],并对该菌生物学特性进行研究。结果表明:病菌菌丝生长以燕麦片培养基(OA)为最适,适宜温度为15—30℃,最适温度为25%,最适pH值为8,菌丝致死温度为51℃(10min),全光照菌丝生长最快;病菌分生孢子萌发最适温度为25℃,在pH值为7条件下萌发率最高,分生孢子致死温度为42℃(10min),光照对孢子萌发影响不大。  相似文献   

7.
通过对沐川县某平推式滑坡调查分析得出其形成机制:在地震波作用下,坡体在‘楔劈'效应、杠杆作用和PGA放大效应耦合作用下,于坡肩处产生震裂裂隙;其后在降雨入渗作用下,裂缝发育、贯通,坡体蠕变加速;最后在强降雨作用下,滑坡启动.模拟计算发现:当降雨强度为2 mm/h时,滑坡复活可能性不大;而当降雨强度分别为5 mm/h、7 mm/h、10 mm/h工况下,持续降雨时间分别达60 h、45 h、30 h时,滑坡有较大概率复活.  相似文献   

8.
松针褐斑病调查和病原鉴定   总被引:6,自引:1,他引:5  
<正>中国南方自七十年代以来广泛引种湿地松(Pinus elliottii)和火炬松(P.laeda)营造用材林。1978年首先在福建发现松针褐斑病,使数千亩国外松林遭受毁灭性损失。1981~1985年的调查表明,湿地松、火炬松和日本黑松(Pinus thunbergii)是高度感病树种;长叶松(P.palustris)、短叶松(P.echinata),加勒比松(P.caribaea)和砂松(P.clausa)感病较轻;而乡土树种马尾松(P.massoniana)和黄山松(P.taiwanensis)高度抗病,海南五针松(P.fenzeliana)未见发病。病害分布很广,已在福建、浙江、江西、江苏、安徽、广东和广西等7个省区的48个县市发现,病原菌鉴定为Lecanosticta acicola (Th(?)m.)Sydow,它是子囊菌Scirrhia acicola (Drian.) Siggers的无性阶段,但有性阶段在中国尚未发现。文章对病害症状和病原菌形态作了描述。  相似文献   

9.
用含有5%松针粉和不含松针粉的饲料饲养海兰褐蛋鸡,对其所产鸡蛋进行品质对比研究.结果表明:松针鸡蛋在蛋重、蛋白重和蛋黄重等指标与普通鸡蛋相比有所增加,差异不显著(P>0.05);蛋壳重、蛋黄指数、水分含量有所下降,但差异不显著(P>0.05);蛋壳厚度、蛋形指数一致;在粗灰分和粗蛋白质含量上松针鸡蛋含量高,呈显著差异(P<0.05),特别是蛋黄颜色差异大,呈极显著差异(P<0.01),松针粉可以有效提高鸡蛋的品质和风味.  相似文献   

10.
云南省玉米灰斑病菌孢子相关生物学特性研究   总被引:1,自引:0,他引:1  
为探明玉米灰斑病在云南省发病较重的原因,该试验在田间条件下,采用人工喷雾接种玉米灰斑病菌,研究玉米灰斑病潜育期、病斑产孢、孢子飞散以及菌龄、温度、湿度和光照对孢子萌发的影响.结果表明:昆明地区玉米灰斑病在感病品种会单4号上的潜育期为12~13d;病斑产孢量随显症天数的增加呈单峰曲线,显症后24~27d病斑产孢量达到最大值;玉米灰斑病菌孢子主要在夜间飞散,风或雨有助于孢子的飞散与传播;菌龄对孢子萌发影响较大,随菌龄的增长,孢子萌发率降低;在10~30℃时,分生孢子均能萌发,但以22℃最适,35℃以上或4℃时均不能萌发;水滴有利于孢子萌发,光照对孢子萌发影响较小.  相似文献   

11.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

12.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

13.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

14.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

15.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

16.
17.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

18.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

19.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

20.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

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