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1.
为了优化种植业结构,促进农民增产增收,笔者在大理市蔬菜主产区大理和七里桥镇,对现有先进适用增产技术进行组装配套,实行水稻-菠菜//青花菜/马铃薯一年四熟高产高效栽培新技术试验示范,示范面积由1998年的0.62hm^2,逐年扩大到达2002年60.70hm^2.经连续五年对六户的1.2hm^,定点跟踪调查实测结果:年平均产稻谷10131.30kg/hm^2菠菜20820.60kg/hm^2,  相似文献   

2.
以密度、氮素、磷素、钾素等为参试因子,采用四元二次回归正交旋转组合设计,对蓖麻杂交新品种通蓖6号高产优质栽培的综合农艺措施进行了研究.结果表明,主要农艺措施对蓖麻产量增减作用的大小依次为:密度〉钾索〉磷素〉氮索.在相同或相似条件下通蓖6号产量大于2052.86kg/hm^2的适宜农艺措施组合为:种植密度以23214-24786株/hm^2为适宜,氮肥(纯N)99.9~169.2kg/hm^2,磷肥(P205)131.63~168.37kg/hm^2,钾肥(K2O)136.27~163.72kg/11m^2为佳.  相似文献   

3.
钼、锌、硼微肥对旱作绿豆产量的影响   总被引:5,自引:0,他引:5  
采用“311—B”二次回归优化设计,V钼、锌、硼微肥为主要探讨因子进行田间试验,建立了绿豆优化施肥模型,根据模型得最高产量施肥量为:在施尿素(45kg/hm^2)、过磷酸钙(120kg/hm^2)、硫酸钾(45kg/hm^2)的基础上,钼酸铵2.88kg/hm^2、硫酸锌10.52kg/hm^2、硼酸4.55kg/hm^2,此时产量为1542.10kg/hm^2,并对钼、锌、硼单因素效应及交互作用作了具体剖析。  相似文献   

4.
宁夏平罗春小麦氮、磷、钾肥肥效及适宜用量   总被引:2,自引:0,他引:2  
用“3414”实验方案研究宁夏平罗县春小麦施用氮、磷、钾肥料的效果和最佳用量.结果表明,与未施肥处理相比.不同施肥处理均显著提高了春小麦籽粒产量;氮、磷、钾肥对春小麦的增产率,氮肥显著高于磷、钾肥,而磷肥又高于钾肥.根据肥料效应方程,确定春小麦最高产量(5231.5kg/hm。)时的氮、磷、钾肥的最佳施肥量分别是258kg/hm^2(N),173kg/hm^2(P2O3),22kg/hm^2(K2O);经济最佳产量(5220.7kg/hm。)时的施肥量是257·9kg/hm^2(N),173.0kg/hm^2(P205),21.6kg/hm^2(K20),氮、磷、钾肥的施肥质量比为1:0.67:0.08.对于指导该地区农业的合理施肥具有重要的参考价值.  相似文献   

5.
宁夏南部山区旱地冬小麦氮磷肥效及最佳用量的研究   总被引:2,自引:0,他引:2  
应用二次饱和D-最优设计研究了宁夏南部山区旱地冬小麦氮磷肥的合理施用量.结果表明,宁夏南部山区旱地施肥量严重不足,化肥增产潜力巨大.在春旱严重的情况下,磷肥的增产作用大于氮肥,氮磷肥配合施用增产效果更加显著,比不施肥时增产1410kg/hm^2,比习惯质种植增产810kg/hm^2,增产率为46.4%.最佳产量为2490kg/hm^2时,施氮量为93.6kg/hm^2,施磷量(P2O5)为108.9kg/hm^2,产投比为3.4:1,效益显著.  相似文献   

6.
采用二次回归旋转组合设计进行超产1号水稻品种不同水平的肥料和密度田间小区试验。探索本品种亩产900公斤的栽培模型。通过2011—2012二年的试验结果表明影响产量的因素顺序为:施氮量〉插秧密度〉施磷量。得出超产1号13500kg/hm^2以上的栽培密度:19.34—24.2穴/m^2,施氮量是172.7—180.0kg/hm^2,施磷量是178.3—200.5kg/hm^2,施钾量是58kg/hm^2。  相似文献   

7.
采用“311-B”二次回归最优设计,以氮、磷、钾肥为供试因子,益都椒产量为目标函数,对益都椒高产施肥进行优化.根据模型得出的最佳施肥量为:尿素344.49kg/hm^2,磷粒691.65kg/hm^2,硫酸钾367.14kg/hm^2.此时产量为4985.193kg/hm^2.并对氮磷钾单因素效应及交互作用作了具体剖析.  相似文献   

8.
河南省玉米生产与肥料施用状况   总被引:5,自引:1,他引:4  
通过对河南省21个县市的玉米生产与肥料施用状况进行农户抽样调查表明:河南省玉米产量以6000-7500kg/hm^2所占比例最大,占到调查农户的50%;4500—6000kg/hm^2产量范围的农户所占比例次之,为31.84%;而小于3500kg/hm^2和大于7500kg/hm^2所占比例分别为1.05%和8.16%.玉米氮肥用量变化为3.1~667.4kg/hm^2,平均为293.3kg/hm^2;磷肥用量变化为0~760.5kg/hm^2,平均97.9kg/hm^2;钾肥用量变化为3.4-50.9kg/hm^2,平均25.9kg/hm^2.玉米生产中氮肥施用量为90—270kg/hm^2占到调查样本的57.04%,其中基肥用量以小于45kg/hm^2所占比例最高,其次为90—135kg/hm^2;追肥用量以135~180kg/hm^2最大,为20.10%.磷肥用量以45—90kg/hm^2所占比例最大,为28.27%;钾肥以不施钾所占比例最高,为39.73%.玉米产量与氮、磷、钾养分总量和氮肥、磷肥和钾肥用量之间关系不显著,氮肥偏生产力以10—20kg/kg所占比例最大,占到调查样本的38.50%,其次为20—30kg/kg,占到调查样本的27.27%;磷肥、钾肥偏生产力均以45—75kg/kg最大,分别占到调查样本的35.46%和26.87%.  相似文献   

9.
在西宁市郊蔬菜节能型目光温室中,采用二次通用旋转组合设计,三因素(密度、氮肥和磷肥)五水平实施方案,研究冬季黄瓜产量与几个重要因素及各因素之间的相互关系。结果表明:在西宁冷凉地区以栽培组合密度为7.00-7.80万株/hm^2,有效氮肥施肥量为450.80~510.40kg/hm^2,有效磷肥施肥量为265.10~290.11kg/hm^2处理,4月份以前生长在目光温室中的黄瓜产量最高,在60000kg/hm^2以上。  相似文献   

10.
典型高产区小麦玉米产量、肥料施用及土壤肥力状况   总被引:4,自引:0,他引:4  
通过对浚县、温县、兰考3个高产区7个样点的小麦、玉米产量和施肥量情况进行调查,结果表明:小麦氮肥用量变化为210.9-376.5kg/hm^2,平均用量254.8kg/hm^2;磷肥用量变化为84-273.8kg/hm^2,平均用量183.1kg/hm^2;钾肥用量变化为0-355.4kg/hm^2,平均用量232.9kg/hm^2.玉米氮肥用量变化为433.5-556.9kg/hm^2,平均用量457.9kg/hm^2;磷肥用量变化为135-234kg/hm^2,平均用量211.3kg/hm^2;钾肥用量变化为90-253kg/hm^2,平均用量157kg/hm^.小麦用氮肥偏生产力为27.33-49.49kg/kg,平均40.03kg/kg;磷肥偏生产力为36.43-109.29kg/kg,平均50.68kg/kg;钾肥偏生产力为25.96-74.31kg/kg,平均44.09kg/kg.玉米上氮肥偏生产力为22.15-28.93kg/kg,平均25.94kg/kg;肥偏生产力为41.03-96.96kg/kg,平均60.07kg/kg;钾肥偏生产力为63.38-145.44kg/kg,平均83.07kg/kg.7个调查样点土壤有机质、全氮、碱解氮普遍较高,但速效磷、钾差别较大.超高产攻关田与农民生产田比较,前者土壤速效磷和速效钾明显高于后者,土壤有机质、全氮、碱解氮也比后者高,但差别较小.  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.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
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   

16.
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   

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.
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   

19.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

20.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

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