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1.
进行了小区试验和大区试验.结果表明,草种以HounelogⅤ、MustangⅡ、CrossfireⅡ、Nassau、Opal混播为佳,并确定了混播比例和播量,草坪修剪高度5cm~8cm,多效唑对草坪生长延缓作用显,年施药1次-2次,年施肥量以N12g/m^2~14g/m^2、P6g/m^2~7g/m^2、K7.2g/m^2~8.4g/m^2为宜,明确了7种主要病虫害的防治措施.此外,在试验基础上,提出了能够满足一般比赛和大众需要、优质、低造价、日常维护管理经济合理的足球场草坪建植和管理技术。  相似文献   

2.
王忠文  王晓琴 《甘肃科技》2011,27(17):186-188
经过试验,总结出了一套适合在干旱荒漠区种植观赏性草坪的建植管理技术.干旱荒漠区选择草地早熟禾占70%、多年生黑麦草占10%、高羊茅占20%共15个品种,以18g/m2的播种量混播下种,播种后坪床用细沙覆盖0.3~0.5cm,苗前和苗期喷灌浇水,加强抚育管理,建坪当年其品质评定指标可达到5级,且青绿期长,翌年返青早,观赏...  相似文献   

3.
建植白三叶(Trifolium repensL.)草坪,播种后出苗速度快、成本低、成坪迅速。白三叶草坪的颜色较浓绿,绿期较长;密度大,对杂草有一定的抗性;叶片宽大,较为光滑,质地好;草坪的高度、粗度、质地较为一致,但叶色深浅不太一致。白三叶草坪刚性、弹性、回弹力、再生力较弱,恢复较慢,导致白三叶草坪不能作为优质草坪来推广。  相似文献   

4.
邱守仁  张韬 《甘肃科技》2008,24(6):145-147
根据白银红砂岩地区的土壤、气候、水分条件,总结出:在该地区,选择种植以抗旱、抗寒、耐盐碱、成坪快的多年生草地早熟禾和多年生黑麦草品种的草坪;播种量在35g/m2以内,实行混播;采用"本土 客土 底肥 化学肥料或添加剂"改土;覆盖0.5~0.8cm的细沙,再用无纺布(或遮阳网)、草袋覆盖,可以保温、保湿,减少风、鸟类危害,防止暴雨和喷灌浇水的冲刷、床面板结,同时促使草坪种子出苗率提高10%~15%,出芽提前3~4d;底肥施足,确保土壤的物理化学特性;在播种前,对土壤进行消毒处理,明显减少草坪病虫害的发生。  相似文献   

5.
经过试验,选择了几种在干旱荒漠区能耐寒、耐旱、耐盐碱、青绿期长,翌年返青早的双子叶草坪草种并总结出了一套适合在干旱荒漠区种植双子叶草坪草的建植管理技术.  相似文献   

6.
不同混播组合草坪质量模糊—回归综合评价   总被引:3,自引:0,他引:3  
运用三因素饱和最优原理和模糊综合评价方法,根据草坪密度、高度、质地、地上生物量、地下生物量、综合评分等六项指标,对以草地早熟禾为建群种,混播紫羊茅、多年生黑麦草的不同组合绿地草坪质量进行了模糊综合评价和回归成分析,模糊综合评价结果表明,在供试的11个混播组合中,当草地早熟禾占67%。紫羊茅占17%,多年生黑麦草占16%,总播种量为15.0g/m^2时,这一组合的模糊隶属度值最大,即第11组合为最佳组合,在模糊综合评价的基础上,把握模糊隶属度值作为因变量,建立了二次咽归模型,通过对回归模型进行寻优计算,得到最优解为:X=-0.3499,X2=-0.394,X=0.271,Y-0.7988,即:草地早熟禾占62%,紫羊茅占20%,多年生黑麦草占18%,总播种量为14.5g.m^2,此结果接近于第11组合,与模糊综合评价结果相似,通过模糊-回归综合评价结果表明,在本试验的生境和管理条件下,在以山地早熟禾为建群种,混播紫羊茅、多年生黑麦草的最佳组合比例是草地早熟禾为9.1-10g/m^2,紫羊茅为2.5-2.6g/m^2,多年生黑麦草为2.5-2.8g/m^2,总播种量为14.5-15.5g/m^2,以这一组合建模的草坪在成坪初期,坪用综合性状最好。  相似文献   

7.
试验研究不同小麦密度和田间配置对套作群体质量和产量的影响.结果表明:小麦密度过大,套作群体内透光率低,群体质量差,虽然以穗多可获得较高小麦产量,但玉米单产低,致使套作群体产量偏低.小麦密度低,通风透光好,以争取较多分蘖、穗大、粒多也能获取高产,并且还有利于玉米生长,套作群体产量较高.行数不同播种量一致的处理在4行150万/hm2的田间配置下,套作群体质量优,产量较高;行数和播种量均不同处理中以3行90万/hm2的田间配置较好.相关分析表明麦/玉套作群体产量的高低主要取决于玉米单产.  相似文献   

8.
试验结果表明,施用旱育保姆包种能明显提高秧苗出苗率、成秧率、单株绿叶数、茎基部宽、白根数、单株鲜干重、后期亩有效穗、结实率及苗期和大田期的抗病性。以每平方米苗床用250g过磷酸钙,氯化钾40g,40g尿素,旱育保姆包种方式表现最好576,7kg/666.7m^2,其次是每平方米苗床用250g过磷酸钙,氯化钾40g,旱育保姆包种方式553.3kg/666.7m^2,对照(ck)常规旱育秧表现最差506.6kg/666.7m^2。  相似文献   

9.
燕麦表型可塑性与繁殖分配的研究   总被引:6,自引:0,他引:6  
在不同的种植密度(种子数/m^2.D1,75;D2,300;D3,525;D4,750;D5,975)下,燕麦(Avena sativa L.)表现出较高的表型可塑性,其单株分蘖数、穗数、小穗数、不孕小穗数、种子数、植物体大小、繁殖体大小、营养体大小、穗粒数、穗粒重和单分蘖重等性状值均随密度的增加而减少,表现出明显的密度依赖性。无效分蘖数及其占分蘖总数的比例、种子单粒重及株高在密度处理间无显著差异,这些性状是非密度依赖的,植物体几何形状的变化模式属异速生长型,繁殖分配比例为一恒定值,对性状间回归分析的结果表明,处子数量和种子大小间不存在负的表型相关,植物单株与单分蘖大小依赖的繁殖输出以及繁殖体与营养体大小间显著的正相关关系都是线笥的,由于单位面积上的繁殖输出随种群密度的增加而增加,因此植物个体繁殖输出的变化不足以补偿因密度变化而造成的差异。  相似文献   

10.
在磷肥(P)施用量分别为0.00、3.50、7.00、14.00、28.00g/m2的样地(0.50m×0.50m)上,播种4.00g高羊茅(Festuca elata Keng ex E.Alexeev)种子,重复4次,研究了不同磷肥施用量对高羊茅株高、分蘖数、叶片数、生物量、光合速率以及叶绿素含量的影响.结果表明:高羊茅的株高与施磷量呈正相关,施磷量为28.00g/m2时株高达到最大值,为10.10cm;磷肥能促进高羊茅的分蘖,施用磷肥的高羊茅在一个月后的分蘖数是不施磷肥对照的1.13~1.33倍;施磷量为7.00g/m2时,高羊茅的叶片数、分蘖数、生物量达到最大值;磷肥能促进高羊茅的光合作用,施磷量为28.00g/m2时净光合速率达到最大值,为4.23μmol·m-2·s-1,磷肥对高羊茅的蒸腾速率影响不显著;不同磷处理样地的高羊茅在施磷肥一个月后其叶绿素a(Chl a)、叶绿素b(Chl b)和叶绿素(Chl)含量均无显著差异.综合分析认为,结合宜昌的地力情况和高羊茅草坪的养护特点,在施用基肥(N 15.00g/m2,K2O 12.00g/m2)的基础上,高羊茅草坪的磷肥施用量以3.50~7.00g/m2为宜.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
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   

13.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

14.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

15.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

16.
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   

17.
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   

18.
19.
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   

20.
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   

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