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Linearity relationship between solvatochromic shifts of stilbazolium-like dyes and modified reaction field function
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作者 詹传郎 王夺元 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2000年第3期418-424,共7页
We analyzed statistically the linear correlation of the solvatochromic shifts of the stilbazolium-like dyes in the nonselected solvents with the reaction field function, L(?T) — bL(n2), and the solvent polarity param... We analyzed statistically the linear correlation of the solvatochromic shifts of the stilbazolium-like dyes in the nonselected solvents with the reaction field function, L(?T) — bL(n2), and the solvent polarity parameter, ENT respectively, and observed that there were not perfectly linearity relationships between them, so we introduced ENT into L(?T) — bL( n2) to form a new reaction field function, L(?T) — bL(n2) + g ENT called as me modified reaction field function, which can be perfectly linearly correlated with the solvatochromic shifts of the stilbazolium-like dyes in the nonselected solvents. 展开更多
关键词 Stilbazolium-like dye solvatochromic shift modified reaction field function
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Molecular properties and potential energy function model of BH under external electric field 被引量:7
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作者 伍冬兰 谭彬 +2 位作者 万慧军 张新琴 谢安东 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第12期194-198,共5页
Using the density functional B3P86/cc-PV5Z method, the geometric structure of BH molecule under different external electric fields is optimized, and the bond lengths, dipole moments, vibration frequencies, and other p... Using the density functional B3P86/cc-PV5Z method, the geometric structure of BH molecule under different external electric fields is optimized, and the bond lengths, dipole moments, vibration frequencies, and other physical properties parameters are obtained. On the basis of setting appropriate parameters, scanning single point energies are obtained by the same method and the potential energy curves under different external fields are also obtained. These results show that the physical property parameters and potential energy curves may change with external electric field, especially in the case of reverse direction electric field. The potential energy function without external electric field is fitted by Morse potential, and the fitting parameters are obtained which are in good agreement with experimental values. In order to obtain the critical dissociation electric parameter, the dipole approximation is adopted to construct a potential model fitting the corresponding potential energy curve of the external electric field. It is found that the fitted critical dissociation electric parameter is consistent with numerical calculation, so that the constructed model is reliable and accurate. These results will provide important theoretical and experimental reference for further studying the molecular spectrum, dynamics, and molecular cooling with Stark effect. 展开更多
关键词 BH molecule potential function model external electric field
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Numerical modeling calculation for the spatial distribution characteristics of horizontal field transfer functions
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作者 龚绍京 陈化然 《Acta Seismologica Sinica(English Edition)》 EI CSCD 2001年第6期676-684,共9页
Applying 3-dimension finite difference method, the distribution characteristics of horizontal field transfer functions for rectangular conductor have been computed, and the law of distribution for Re-part and Im-part ... Applying 3-dimension finite difference method, the distribution characteristics of horizontal field transfer functions for rectangular conductor have been computed, and the law of distribution for Re-part and Im-part has been given. The influences of source field period, the conductivity, the buried depth and the length of the conductor on the transfer functions were studied. The extrema of transfer functions appear at the center, the four corners and around the edges of conductor, and move with the edges. This feature demonstrates that around the edges are best places for transfer functions' observation. 展开更多
关键词 numerical modeling 3-D finite difference method horizontal field transfer function spatial distribution characteristics
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The Analytical Potential Energy Function of NH Radical Molecule in External Electric Field 被引量:5
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作者 伍冬兰 谭彬 +2 位作者 万慧军 谢安东 丁大军 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第7期34-37,共4页
The geometric structures of an Nit radical in different external electric fields are optimized by using the density functional B3P86/cc-PVSZ method, and the bond lengths, dipole moments, vibration frequencies and IR s... The geometric structures of an Nit radical in different external electric fields are optimized by using the density functional B3P86/cc-PVSZ method, and the bond lengths, dipole moments, vibration frequencies and IR spectrum are obtained. The potential energy curves are gained by the CCSD (T) method with the same basis set. These results indicate that the physical property parameters and potential energy curves may change with the external electric field, especially in the reverse direction electric field. The potential energy function of zero field is fitted by the Morse potential, and the fitting parameters are in good accordance with the experimental data. The potential energy functions of different external electric fields are fitted adopting the constructed potential model. The fitted critical dissociation electric parameters are shown to be consistent with the numerical calculation, and the relative errors are only 0.27% and 6.61%, hence the constructed model is reliable and accurate. The present results provide an important reference for further study of the molecular spectrum, dynamics and molecular cooling with Stark effect. 展开更多
关键词 The Analytical Potential Energy function of NH Radical Molecule in External Electric field NH
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A FUNCTION MINIMIZATION CALCULATION OF CYCLONE 10 MAGNETIC FIELDS
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作者 S.Zaremba 王良明 《Nuclear Science and Techniques》 SCIE CAS CSCD 1991年第3期129-134,共6页
By app(?)ing function minimization calculation method, two function expressions are used to simulate the magnetic field measured for cyclotron Cyclone 10 in azimuth and radius The numerical fitting curves are consiste... By app(?)ing function minimization calculation method, two function expressions are used to simulate the magnetic field measured for cyclotron Cyclone 10 in azimuth and radius The numerical fitting curves are consistent with magnetic field measured. In most pl(?)es, the accuracies are several thousandth, except those errors to be pointed out in paper. 展开更多
关键词 function MINIMIZATION CALCULATION MINUIT program Periodic function SEEKING REMAINDER function Fringing field function simulation
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Stress Field Analyses of Functionally Gradient Ceramic Tool by FEM
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作者 Ning FAN , Xing AI and Jun ZHAO Department of Mechanical Engineering, Shandong University,Jinan 250061, China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2001年第4期466-468,共3页
The cutting properties of the functionally gradient ceramic cutting tools relate closely to the gradient distribution. A cutting model of the functionally gradient ceramic tool is firstly designed in the present paper... The cutting properties of the functionally gradient ceramic cutting tools relate closely to the gradient distribution. A cutting model of the functionally gradient ceramic tool is firstly designed in the present paper. The optimum of gradient distribution is obtained by way of the FEM analyses. 展开更多
关键词 Stress field Analyses of functionally Gradient Ceramic Tool by FEM TOOL
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A NEW METHOD FOR SOLVING DYADIC GREEN'S FUNCTION OF ELECTROMAGNETIC FIELD
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作者 宋文淼 《Journal of Electronics(China)》 1990年第2期122-134,共13页
A new method for solving electromagnetic field boundary value problem is given.Byusing this method,the boundary value problem of the vector wave equation can be transformedinto the independent boundary value problem o... A new method for solving electromagnetic field boundary value problem is given.Byusing this method,the boundary value problem of the vector wave equation can be transformedinto the independent boundary value problem of scalar wave equations and the two additionalvector differential operations.All the dyadic Green’s functions got by eigenfunction expansionof the dyadic Green’s function can be got by this method easily and some of the dyadic Green’sfunctions for complex systems which are very difficult to get by the ordinary method have beengot by this new method.The dyadic Green’s function for a dielectric loaded cavity is one of thegiven examples. 展开更多
关键词 DYADIC Green’s function ROTATIONAL field Irrotational field VECTOR wave function
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Construction Theory of Function on Local Fields 被引量:1
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作者 Weiyi Su 《Analysis in Theory and Applications》 CSCD 2015年第1期25-44,共20页
We establish the construction theory of function based upon a local field Kp as underlying space. By virture of the concept of pseudo-differential operator, we introduce "fractal calculus" (or, p-type calculus, or,... We establish the construction theory of function based upon a local field Kp as underlying space. By virture of the concept of pseudo-differential operator, we introduce "fractal calculus" (or, p-type calculus, or, Gibbs-Butzer calculus). Then, show the Jackson direct approximation theorems, Bermstein inverse approximation theorems and the equivalent approximation theorems for compact group D(C Kp) and locally compact group Kp^+-(= Kp), so that the foundation of construction theory of function on local fields is established. Moreover, the Jackson type, Bernstein type, and equivalent approximation theorems on the HOlder-type space C^σ(Kp), σ 〉0, are proved; then the equivalent approximation theorem on Sobolev-type space Wr(Kp), σ≥0, 1≤r 〈∞, is shown. 展开更多
关键词 Construction theory of function local field fractal calculus approximation theorem HOlder-type space.
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The anomalous reactions of the geomagnetic horizontal field transfer functions before Tangshan earthquake
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作者 龚绍京 陈化然 +2 位作者 张翠芬 杨程君 马淑芹 《Acta Seismologica Sinica(English Edition)》 CSCD 1997年第1期60-69,共10页
We have collected the data of variometers in period from 1972 through 1984 at Changli and Baijiatuan stations. The results calculated from 19 groups of data show: 1) There are no significant anomalies of A... We have collected the data of variometers in period from 1972 through 1984 at Changli and Baijiatuan stations. The results calculated from 19 groups of data show: 1) There are no significant anomalies of A, B at Baijiatuan and that of B at Changli, but there are evident anomalous changes for A u, A v at Changli station. This result basically agrees to the a, b calculated using the method of measuring magnetograms, which demonstrates that the anomalies limited in the aftershock area and its neighbouring regions. 2) There are some changes of the inter station transfer functions of C u, C v, F u, F v before Tangshan earthquake, and the changes of the image parts C v, F v are more obvious, which is in agreement with the research results for Hualian earthquake. However, according to the results of Carlisle M =5.0 earthquake by Beamish(1982), the real parts F u, C u change more significantly. 展开更多
关键词 horizontal field inter station transfer functions underground electric structure abnormal field normal field
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Flood Reduction Function of Paddy Rice Fields under Different Water Saving Irrigation Techniques 被引量:1
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作者 Joko Sujono 《Journal of Water Resource and Protection》 2010年第6期555-559,共5页
This study is conducted to investigate the function of paddy fields for flood reduction under different water saving irrigation techniques. A daily water balance component data including rainfall, percolation, and ove... This study is conducted to investigate the function of paddy fields for flood reduction under different water saving irrigation techniques. A daily water balance component data including rainfall, percolation, and overflow through the paddy field levee were collected from experimental paddy rice fields during rainy season cultivation. Results show that paddy field was very effective in flood reduction. More than 40% of rainfall could be stored in the paddy fields. However, the effectiveness of paddy fields in flood reduction was highly depends on the WSI technique used. Semi dry cultivation technique was the most effective one in terms of flood reduction. It retained the rainfall up to 55.7% (365 mm) of the total rainfall (636 mm) without reducing the yield. In terms of flood volume reduction, the alternate wetting and drying performed similarly with traditional continuous flooding, i.e., 37.2% and 40.8%, respectively. 展开更多
关键词 FLOOD REDUCTION function Water SAVING IRRIGATION PADDY field
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CHAINS OF FUNCTION SPACES OVER EUCLIDIAN SPACES AND LOCAL FIELDS
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作者 Zhaoxi Wang 《Analysis in Theory and Applications》 2009年第1期92-100,共9页
The Lipschitz class Lip(K, α) on a local field K is defined in [10], and an equivalent relationship between the Ho¨lder type space Cα(K)[9] and Lip(K,α) is given. In this note, we give a 'chain of function... The Lipschitz class Lip(K, α) on a local field K is defined in [10], and an equivalent relationship between the Ho¨lder type space Cα(K)[9] and Lip(K,α) is given. In this note, we give a 'chain of function spaces' over Euclidian space by defining higher order continuous modulus in R, and point out that there is no need of higher order continuous modulus for describing the chain of function spaces over local fields. 展开更多
关键词 local field Lipschitz class function space morder continuous modulus morder Lipschitz class
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Semi-supervised classification based on Markov Random Field and Robust Error Function
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作者 LIN Qing SHAN Ping-ping +1 位作者 WANG Shi-tong ZHAN Yong-zhao 《通讯和计算机(中英文版)》 2009年第4期1-5,共5页
关键词 半管理 MARKOV随机场 误差函数 能量函数
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Effect of gradient magnetic field on physiochemistry functions of rice seedlings
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《Chinese Rice Research Newsletter》 1999年第1期10-10,共1页
Rice varieties Handao 2,Zhongbai 4,Han-jingzi,and Akihikari were treated with gradi-ent magnetic fileld to study the effect of gradi-ent field on rice.The magnetic field was madeup of 12 plots magnetic plates arranged... Rice varieties Handao 2,Zhongbai 4,Han-jingzi,and Akihikari were treated with gradi-ent magnetic fileld to study the effect of gradi-ent field on rice.The magnetic field was madeup of 12 plots magnetic plates arranged in eachother south and north pole.The magneticstrength was 0-40 mT.Each four varieties wasput under the magnetic plate 15 cm away,andwent through the magnetic field with the speedof 20 cm/s.The same varieties without thetreatment were used as CK.Both of the seedswere soaked in water for 48 h in room temper-ature,and then sprouted on the porcelain platewith absorbed water paper.When the 展开更多
关键词 Effect of gradient magnetic field on physiochemistry functions of rice seedlings
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Heun Functions Describing Fermions Evolving in Parallel Electric and Magnetic Fields
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作者 MARINA-AURA Dariescu CIPRIAN Dariescu 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第7期21-24,共4页
The present work deals with the behavior of fermions moving in a static magnetic induction and a time-harmonic electric field, both oriented along Oz. For the ultra-relativistic particles described by a Heun double co... The present work deals with the behavior of fermions moving in a static magnetic induction and a time-harmonic electric field, both oriented along Oz. For the ultra-relativistic particles described by a Heun double confluent equation, we derive the corresponding wave functions and the conserved current density components. 展开更多
关键词 exp Heun functions Describing Fermions Evolving in Parallel Electric and Magnetic fields
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Higher-order crack tip fields for functionally graded material plate with transverse shear deformation
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作者 Dianhui HOU Xiao CHONG +1 位作者 Guixiang HAO Yao DAI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2016年第6期695-706,共12页
The crack tip fields are investigated for a cracked functionally graded material (FGM) plate by Reissner's linear plate theory with the consideration of the transverse shear deformation generated by bending. The el... The crack tip fields are investigated for a cracked functionally graded material (FGM) plate by Reissner's linear plate theory with the consideration of the transverse shear deformation generated by bending. The elastic modulus and Poisson's ratio of the functionally graded plates are assumed to vary continuously through the coordinate y, according to a linear law and a constant, respectively. The governing equations, i.e., the 6th-order partial differential equations with variable coefficients, are derived in the polar coordinate system based on Reissner's plate theory. Furthermore, the generalized displacements are treated in a separation-of-variable form, and the higher-order crack tip fields of the cracked FGM plate are obtained by the eigen-expansion method. It is found that the analytic solutions degenerate to the corresponding fields of the isotropic homogeneous plate with Reissner's effect when the in-homogeneity parameter approaches zero. 展开更多
关键词 crack tip field Reissner's effect PLATE functionally graded material (FGM) eigen-expansion method
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HALF-SPACE GREENS'S FUNCTION DUE TO A SPATIALLY HARMONIC LINE LOAD AND SCATTERED FIELDS IN THE FAR FIELD REGION
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作者 Peng Zhu(Changsha Communication Institute.Changsha 4110076.China)Li Zailiang(Huazhong University of Science and Technology.Wuhan 430074,China) 《Acta Mechanica Solida Sinica》 SCIE EI 1997年第1期56-65,共10页
Half-space Green's function due to a spatially harmonic line load has been expressed as a sum of the full-space Green's functions and a 2-D integral representation of the reflected waves by the free surface of... Half-space Green's function due to a spatially harmonic line load has been expressed as a sum of the full-space Green's functions and a 2-D integral representation of the reflected waves by the free surface of the half-space.By using the obtained half-space Green's function,an integral rep- resentation of the scattered waves by a cylindrical obstacle is then derived.Finally,by analyzing the far-zone behavior of the integrands of the integral representation.the far-field pattern of the scattered waves in a half-space obtained. 展开更多
关键词 spatially harmonic line load half-space Green's function far-field of scattered waves
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改进人工势场算法的路径规划 被引量:1
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作者 张铮 薛波 +2 位作者 柯子鹏 金子博 邱达河 《西安理工大学学报》 CAS 北大核心 2024年第1期27-35,共9页
人工势场法是一种适用于局部路径规划的算法,针对人工势场法存在的目标不可达、局部极小值等固有缺陷,提出了一种改进后的人工势场法。首先针对目标不可达问题,将引力影响因子添加到斥力场的生成中,改进斥力场函数,从而避免引力与斥力... 人工势场法是一种适用于局部路径规划的算法,针对人工势场法存在的目标不可达、局部极小值等固有缺陷,提出了一种改进后的人工势场法。首先针对目标不可达问题,将引力影响因子添加到斥力场的生成中,改进斥力场函数,从而避免引力与斥力合力为零的情况。针对局部极小值问题,通过设立虚拟目标点来引入额外外力,打破机器人的平衡问题。通过与其他算法的对比实验,仿真结果显示,改进人工势场法规划的路径长度和消耗时间都更短,稳定性更强。 展开更多
关键词 人工势场 路径规划 势场函数 虚拟目标点 移动机器人
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The Effect of Aging on Erectile Function Induced by Apomorphine and Electric Field Stimulation to Rat
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作者 李铮 郑松 +2 位作者 向祖琼 刘勇 王益鑫 《Journal of Reproduction and Contraception》 CAS 2002年第1期16-21,共6页
Objective To explore the effect and mechanism of aging on erection by using rat model. Materials & Methods Forty male SD rats of 3, 9, 18 and 24 months old were divided into 4 groups equally according to thei... Objective To explore the effect and mechanism of aging on erection by using rat model. Materials & Methods Forty male SD rats of 3, 9, 18 and 24 months old were divided into 4 groups equally according to their age. Apomorphine given subcutaneously and cavernous nerve electric field stimulation was used to induce erection of rats. Results The successful erection rate, number of erection times, and intracavernous pressure (ICP) in the rats of 18 and 24 month old was significantly lower than that of 3 and 9 month old. Conclusion The erectile function in aging rats is deteriorated. The damage mechanism with aging might be related to dopaminergic system in central nerves. 展开更多
关键词 erectile function AGING APOMORPHINE electric field stimulation RAT
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Field Application of the Mycorrhizal Fungus <i>Rhizophagus irregularis</i>Increases the Yield of Wheat Crop and Affects Soil Microbial Functionalities 被引量:1
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作者 Sanaa Wahbi Yves Prin +5 位作者 Tasnime Maghraoui Hervé Sanguin Jean Thioulouse Khalid Oufdou Mohamed Hafidi Robin Duponnois 《American Journal of Plant Sciences》 2015年第19期3205-3215,共11页
The aim of this study was to test the impact of Rhizophagus irregularis, an arbuscular mycorrhizal fungus (AMF), on durum wheat growth and soil microbial functionalities in a field inoculation trial conducted in Moroc... The aim of this study was to test the impact of Rhizophagus irregularis, an arbuscular mycorrhizal fungus (AMF), on durum wheat growth and soil microbial functionalities in a field inoculation trial conducted in Morocco. The results showed that i) the R. irregularis inoculum effectively improved wheat growth, ii) wheat growth promotion depended on the soil mycorrhizal infectivity and iii) functional abilities of soil microflora depended on AMF inoculation. This study confirms that field AMF inoculation can be proposed as an effective agronomic practice in wheat production and as a sustainable cultural practice to manage soil biofunctioning. To fully promote inoculation practices, a better knowledge of AMF ecology has to be acquired to better adapt AMF inoculation to environmental conditions, and thus warrant better yields and agricultural sustainability. 展开更多
关键词 ARBUSCULAR MYCORRHIZAL Fungi field-Grown WHEAT MYCORRHIZAL field Inoculation Nutrient Uptake Microbial Soil functions
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苜蓿草田间作功能植物对苜蓿蓟马及天敌小花蝽种群的影响
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作者 魏淑花 刘学琴 +2 位作者 王颖 刘畅 张蓉 《中国生物防治学报》 CSCD 北大核心 2024年第1期99-107,共9页
本研究将苜蓿Medicago sativa与百脉根Lotus corniculatus、红豆草Onobrychis viciifolia、白三叶Trifolium repens、小冠花Coronilla varia及除虫菊Tanacetum cinerariifolium等不同功能植物以不同比例进行间作,在田间系统监测基础上,... 本研究将苜蓿Medicago sativa与百脉根Lotus corniculatus、红豆草Onobrychis viciifolia、白三叶Trifolium repens、小冠花Coronilla varia及除虫菊Tanacetum cinerariifolium等不同功能植物以不同比例进行间作,在田间系统监测基础上,研究基于有害生物推拉策略和生物多样性保护的苜蓿蓟马生态调控技术。结果表明,苜蓿刈割前,苜蓿草田内蓟马及天敌小花蝽Orius similis的数量均显著高于对应间作的功能植物区;刈割1周后,与百脉根、红豆草、白三叶和除虫菊间作的苜蓿草田内小花蝽种群密度显著下降,对应的功能植物区内小花蝽数量显著上升,其中,百脉根、红豆草及白三叶3种功能植物区内小花蝽种群密度分别由刈割前的3.67头/10复网、3.00头/10复网、3.67头/10复网增加到了刈割1周后的11.50头/10复网、29.17头/10复网、15.00头/10复网,分别是刈割前的3.13倍、9.73倍和4.09倍,苜蓿草田内蓟马种群密度显著下降,对应不同功能植物区内蓟马种群密度不同,在红豆草和白三叶功能植物区内显著升高,而在其它区内刈割前无显著差异;刈割2周后,苜蓿再生期蓟马种群密度显著上升,各功能植物区内的小花蝽密度显著下降,与其间作的苜蓿草田内小花蝽种群数量显著增加;刈割3~4周后,随着苜蓿草田内蓟马种群密度的下降,其天敌小花蝽种群数量显著下降,不同功能植物区间小花蝽及蓟马种群密度变化不显著。苜蓿与五种功能植物以4:1比例间作对蓟马的调控效果由高到低依次为白三叶,除虫菊,红豆草,百脉根,小冠花。本研究为保护苜蓿草田生态系统天敌发挥生态效能提供可借鉴的策略与方法。 展开更多
关键词 苜蓿草田 功能植物 间作 蓟马 小花蝽 生态调控
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