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《光宣诗坛点将录》“大小方”考——“维扬俊人”系列考证之一
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作者 卞孝萱 《历史文献研究》 2008年第1期1-18,共18页
从"同光体"领袖陈三立到《光宣诗坛点将录》撰者汪国垣,都充分肯定方尔谦、尔咸兄弟的诗才。二方名满淮海,而钱萼孙《清诗纪事》光宣卷中,无二方片词只字,可见文献湮没。今据我多年来寻访到的资料,写成此文。首先考证"... 从"同光体"领袖陈三立到《光宣诗坛点将录》撰者汪国垣,都充分肯定方尔谦、尔咸兄弟的诗才。二方名满淮海,而钱萼孙《清诗纪事》光宣卷中,无二方片词只字,可见文献湮没。今据我多年来寻访到的资料,写成此文。首先考证"大小方"齐名合称之由来及其家世、家庭教育与主要的交游情况。接着考证二方之异同:大方擅长骈文、诗,最工联语,有"联圣"之誉,并精鉴赏,富收藏;小方擅长诗、词,亦作联语,篆刻、弈棋无所不能。二方都精通盐务,大方从事盐政工作,小方则凭借他与扬州盐商的特殊关系,在辛亥革命时扮演了沟通军商的重要角色。二方都关注教育,大方被袁世凯聘为家庭教师,小方在扬州提倡新式教育。大方性豪放,有狂名;小方工心计,病缠身。二方无诗文集传世,本文辑录佚作数篇,以见一斑。 展开更多
关键词 大小方 尔谦 尔咸
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样方大小对苔藓植物生态学指标的影响 被引量:5
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作者 沈蕾 郭水良 +2 位作者 宋洪涛 娄玉霞 曹同 《广西植物》 CAS CSCD 北大核心 2011年第2期198-203,共6页
为了分析样方大小对苔藓植物生态指标的影响,在环境相对一致的条件下,在各样点以巢式取样法调查苔藓植物盖度,取样的大小分别为20 cm×20 cm,30 cm×30 cm,40 cm×40 cm,50 cm×50 cm,60 cm×60 cm。通过统计发现,... 为了分析样方大小对苔藓植物生态指标的影响,在环境相对一致的条件下,在各样点以巢式取样法调查苔藓植物盖度,取样的大小分别为20 cm×20 cm,30 cm×30 cm,40 cm×40 cm,50 cm×50 cm,60 cm×60 cm。通过统计发现,随着取样面积的增加,目测法所获得的优势种、总的苔藓植物的盖度呈现下降趋势,但是非优势种和偶见种的盖度却有上升趋势;随着样方大小之间差异的扩大,所得调查数据间的差异也在扩大;随着取样面积的增加,样方中苔藓植物的多样性指数、生态位宽度和重叠值、苔藓植物的平均种数均符合饱和曲线的增加规律;取样面积大小对环境因子与苔藓植物分布之间关系的分析结果也有明显影响;在生境相对一致的土生环境下,苔藓植物的取样面积可考虑在40 cm×40 cm^50 cm×50 cm的范围内。 展开更多
关键词 苔藓植物 大小 生态位 多样性 最小面积
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昆虫种群简单随机抽样最适样方大小的确定 被引量:6
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作者 张连翔 刘学增 《河北林学院学报》 1993年第2期132-139,共8页
本文就昆虫种群简单随机抽样技术中最适样方大小的确定方法作了较为系统的总结,它们是:①按Iwao m-m模型确定最适样方大小;②按改进的Iwao m-m模型确定最适样方大小;③按再次改进的Iwaom-m模型确定最适样方大小;④按m-m幂法则确定最适... 本文就昆虫种群简单随机抽样技术中最适样方大小的确定方法作了较为系统的总结,它们是:①按Iwao m-m模型确定最适样方大小;②按改进的Iwao m-m模型确定最适样方大小;③按再次改进的Iwaom-m模型确定最适样方大小;④按m-m幂法则确定最适佯方大小;⑤按Taylor幂法则确定最适样方大小;⑥按负二项分布参数k确定最适样方大小;⑦按Morisita Iδ指数确定最适样方大小.对这些方法均用实例进行了验证.同时,文中还提出了一些新的模型和方法. 展开更多
关键词 简单随机抽样 最适样大小 昆虫种群 抽样调查
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油松毛虫蛹种群简单随机抽样最适样方大小的确定方法 被引量:2
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作者 金来武 赵瑞华 《辽宁林业科技》 2001年第2期42-44,共3页
在种群空间格局研究的基础上 ,采用 7种方法对油松毛虫蛹种群简单随机抽样技术中最适样方大小的确定问题进行了研究。结果是蛹种群在u =1时抽样误差最低 ,即以单株油松为样方时最为适宜。此外 ,文中还给出了考虑抽样花费时确定最适样方... 在种群空间格局研究的基础上 ,采用 7种方法对油松毛虫蛹种群简单随机抽样技术中最适样方大小的确定问题进行了研究。结果是蛹种群在u =1时抽样误差最低 ,即以单株油松为样方时最为适宜。此外 ,文中还给出了考虑抽样花费时确定最适样方大小的各种方法 。 展开更多
关键词 油松毛虫 蛹种群 空间格局 最适样大小 抽样误差
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森林林下植被生物量收获的样方选择和模型 被引量:71
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作者 杨昆 管东生 《生态学报》 CAS CSCD 北大核心 2007年第2期705-714,共10页
在控制误差内寻求样方的最小面积和最少样方数量是植被生态学野外研究的重要问题。在综合考虑取样的边界效应和时间、劳力消耗的基础上,研究了在控制误差内测定森林林下植被生物量时应选择的最佳样方大小和数量,并找出最佳的自变量拟合... 在控制误差内寻求样方的最小面积和最少样方数量是植被生态学野外研究的重要问题。在综合考虑取样的边界效应和时间、劳力消耗的基础上,研究了在控制误差内测定森林林下植被生物量时应选择的最佳样方大小和数量,并找出最佳的自变量拟合了估算林下植被生物量的预测方程。结果表明,利用Wiegert的方法测定研究区林下植被生物量取样方案,得出0.25m2的小样方为最佳取样面积。但小样方受边界效应的影响很大,会产生过高的生物量估计。通过分析了边界效应的影响和生物量相对平均值的变化,得出2m×1m是本研究的最佳样方面积,而10个2m×1m的样方能把标准误差控制在生物量平均值的10%以内。灌木生物量回归方程所选取的3个自变量D2H、CH和PH中,CH与灌木生物量的相关性和以CH为自变量的线性回归方程的拟合度较其他2个变量好。而以PH为自变量的灌木生物量预测方程在实际操作中能提高研究的简便性和效率。以PH为自变量的林下草本层单位面积生物量的预测方程分别为WU=11.65+4.25(PH)和WD=24.23+6.85(PH)。 展开更多
关键词 林下植被 生物量估算 大小 数量
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假眼小绿叶蝉与捕食性天敌蜘蛛的空间关系研究 被引量:9
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作者 刘飞飞 柯胜兵 +7 位作者 王建盼 毕守东 周夏芝 邹运鼎 党凤花 徐劲峰 禹坤 赵学娟 《西北农林科技大学学报(自然科学版)》 CSCD 北大核心 2016年第6期99-110,共12页
【目的】分析天敌蜘蛛对假眼小绿叶蝉空间跟随关系的密切程度及抽样样方的大小,为评价假眼小绿叶蝉的天敌优势种和确定样方大小提供科学依据。【方法】用聚块样方方差分析法、灰色关联度分析法、扩散系数法和p指数法,对潜山县茶园假... 【目的】分析天敌蜘蛛对假眼小绿叶蝉空间跟随关系的密切程度及抽样样方的大小,为评价假眼小绿叶蝉的天敌优势种和确定样方大小提供科学依据。【方法】用聚块样方方差分析法、灰色关联度分析法、扩散系数法和p指数法,对潜山县茶园假眼小绿叶蝉及其8种蜘蛛类天敌空间跟随关系的密切程度、种群聚集的原因和个体种群聚集时占据的最小面积进行分析。【结果】与假眼小绿叶蝉空间跟随关系密切的天敌是八点球腹蛛、三突花蟹蛛和斑管巢蛛,其关联度值分别为0.8120,0.7681和0.7572,跟随关系较不密切的天敌是鞍形花蟹蛛,二者的关联度值为0.6459。在聚块内有1-8个基本样方时,随着聚块内基本样方数的增多,聚集格局的扩散系数(c值)不断增大,均匀格局和随机格局的扩散系数不断减小。假眼小绿叶蝉及其天敌在聚块基本样方数为2,4,8,16和32时的空间分布聚集程度与聚块基本样方数为1时差异均不显著。假眼小绿叶蝉的种群聚集均数x均大于2,表明聚集是由其本身原因造成的,在种群聚集均数为正值时,随着聚块内基本样方数的增加,种群聚集均数不断增大。假眼小绿叶蝉个体群聚集格局的最小面积是聚块中有i个基本样方,即面积不小于1.7m^2。【结论】采用聚块样方方差分析法、灰色关联度分析法、扩散系数法和p指数法,不仅可以判别天敌与害虫空间跟随关系的密切程度,而且可以科学确定抽样样方的最小面积,是较为理想的空间格局分析方法。 展开更多
关键词 假眼小绿叶蝉 天敌 空间跟随关系 大小
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联结度指数构造模型及其应用 被引量:4
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作者 罗传文 《林业科学》 EI CAS CSCD 北大核心 2004年第2期183-188,共6页
The model of interspecific association index was constructed in this paper. It is proved that the classical interspecific association statistic is the special case of this model. The derivation of this paper got the u... The model of interspecific association index was constructed in this paper. It is proved that the classical interspecific association statistic is the special case of this model. The derivation of this paper got the unification between interspecific association measurement and its statistic, and between its qualitative analysis and quantitative analysis. The essence of interspecific association index was opened out and the enactment of interspecific association index was developed. Four part specific association indices were constructed on this base, all of the specific association indices were computed respectively to the different radius of sample circle by the permanent sample plot data in Moarshan National Forest Park, Heilongjiang Province, P. R. China. The fourth index was less affected by the size of sample circle, was steady and widely practical. 展开更多
关键词 联结度指数 构造模型 植物种间联结关系 大小 统计量 联结度
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Two-echelon inventory model with service level constraint and controllable lead time sensitive to order quantity 被引量:3
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作者 李果 关旭 +1 位作者 刘梦麒 单汩源 《Journal of Central South University》 SCIE EI CAS 2013年第11期3324-3333,共10页
The decision-making and optimization of two-echelon inventory coordination were analyzed with service level constraint and controllable lead time sensitive to order quantity.First,the basic model of this problem was e... The decision-making and optimization of two-echelon inventory coordination were analyzed with service level constraint and controllable lead time sensitive to order quantity.First,the basic model of this problem was established and based on relevant analysis,the original model could be transformed by minimax method.Then,the optimal order quantity and production quantity influenced by service level constraint were analyzed and the boundary of optimal order quantity and production quantity was given.According to this boundary,the effective method and tactics were put forward to solve the transformed model.In case analysis,the optimal expected total cost of two-echelon inventory can be obtained and it was analyzed how service level constraint and safety factor influence the optimal expected total cost of two-echelon inventory.The results show that the optimal expected total cost of two-echelon inventory is constrained by the higher constraint between service level constraint and safety factor. 展开更多
关键词 service level constraint safety factor controllable lead time sensitivity to order quantity two-echelon
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Removal of Nitrophenols by Adsorption Using β-Cyclodextrin Modified Zeolites 被引量:8
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作者 李效红 赵保卫 +1 位作者 朱琨 郝学奎 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第6期938-943,共6页
Removal of nitrophenols (NPs) from aqueous solutions through the adsorption process by using cationic β-cyclodextrin (CCD) modified zeolite (CCDMZ) was investigated. The effects of particle size, contact time, ... Removal of nitrophenols (NPs) from aqueous solutions through the adsorption process by using cationic β-cyclodextrin (CCD) modified zeolite (CCDMZ) was investigated. The effects of particle size, contact time, solution pH values and sodium chloride content in the aqueous on adsorption capacity were evaluated through a series of batch experiments. The results showed that CCDMZ had a higher adsorption capacity for removing NPs at a size fraction of 0.45-0.9 mm while adsorption of NPs on CCDMZ reached equilibrium within 60 min. The adsorption process was apparently influenced by pH values and sodium chloride content in aqueous solution. To ascertain the mechanisms of sorption, the experimental data were modeled by using the pseudo-first and pseudo-second order kinetic equations, and the results indicated that the adsorption kinetics of NPs on CCDMZ well-matched with the pseudo-second order rate expression. 展开更多
关键词 ADSORPTION ZEOLITE MODIFICATION NITROPHENOLS adsorption kinetics
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Novel K-best detection algorithms for MIMO system
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作者 向星宇 仲文 《Journal of Southeast University(English Edition)》 EI CAS 2009年第1期1-5,共5页
Aiming at the optimum path excluding characteristics and the full constellation searching characteristics of the K-best detection algorithm, an improved-performance K-best detection algorithm and several reduced-compl... Aiming at the optimum path excluding characteristics and the full constellation searching characteristics of the K-best detection algorithm, an improved-performance K-best detection algorithm and several reduced-complexity K-best detection algorithms are proposed. The improved-performance K-best detection algorithm deploys minimum mean square error (MMSE) filtering of a channel matrix before QR decomposition. This algorithm can decrease the probability of excluding the optimum path and achieve better performance. The reducedcomplexity K-best detection algorithms utilize a sphere decoding method to reduce searching constellation points. Simulation results show that the improved performance K-best detection algorithm obtains a 1 dB performance gain compared to the K- best detection algorithm based on sorted QR decomposition (SQRD). Performance loss occurs when K = 4 in reduced complexity K-best detection algorithms. When K = 8, the reduced complexity K-best detection algorithms require less computational effort compared with traditional K-best detection algorithms and achieve the same performance. 展开更多
关键词 sorted QR decomposition K-best sphere decoding maximum-likelihood detection minimum mean square error
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Statistical Analysis for the Birnbaum-Saunders Fatigue Life Distribution under Multiply Type-ⅡCensoring 被引量:5
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作者 WANG Rong-hua FEI He-liang 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2006年第1期15-27,共13页
In present paper, we derive the quasi-least squares estimation(QLSE) and approximate maximum likelihood estimation(AMLE) for the Birnbaum-Saunders fatigue life distribution under multiply Type-Ⅱcensoring. Furthermore... In present paper, we derive the quasi-least squares estimation(QLSE) and approximate maximum likelihood estimation(AMLE) for the Birnbaum-Saunders fatigue life distribution under multiply Type-Ⅱcensoring. Furthermore, we get the variance and covariance of the approximate maximum likelihood estimation. 展开更多
关键词 Birnbaum-Saunders fatigue life distribution multiply Type-Ⅱ censoring quasi-least squares estimation approximate maximum likelihood estimation
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On the Minimum Spanning Tree Determined by n Points in the Unit Square
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作者 叶继昌 徐寅峰 徐成贤 《Chinese Quarterly Journal of Mathematics》 CSCD 1999年第2期76-82, ,共7页
Let P n be a set of n points in the unit square S,l(P n) denoe the length of the minimum spanning tree of P n, andC n= max P nSl(P n), n=2,3,… In this paper,the exact value of C n for n=2,3,4 and the corresponding co... Let P n be a set of n points in the unit square S,l(P n) denoe the length of the minimum spanning tree of P n, andC n= max P nSl(P n), n=2,3,… In this paper,the exact value of C n for n=2,3,4 and the corresponding configurations are given. Additionally,the conjectures of the configuration for n=5,6,7,8,9 are proposed. 展开更多
关键词 minimum spanning tree maximin problem CONFIGURATION
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Aggregation Processes with Catalysis-Driven Decomposition
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作者 XIANG Rong ZHUANG You-Yi KE Jian-Hong LIN Zhen-Quan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第10期622-626,共5页
We propose a three-species aggregation model with catalysis-driven decomposition. Based on the mean-field rate equations, we investigate the evoIution behavior of the system with the size-dependent catalysis-driven de... We propose a three-species aggregation model with catalysis-driven decomposition. Based on the mean-field rate equations, we investigate the evoIution behavior of the system with the size-dependent catalysis-driven decomposition rate J(i; j; k) = Jijk^v and the constant aggregation rates. The results show that the cluster size distribution of the species without decomposition can always obey the conventional scaling law in the case of 0 ≤v ≤ 1, while the kinetic evolution of the decomposed species depends crucially on the index v. Moreover, the total size of the species without decomposition can keep a nonzero value at large times, while the total size of the decomposed species decreases exponentially with time and vanishes finally. 展开更多
关键词 DECOMPOSITION kinetic behavior scaling law rate equation
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Solving constrained minimax problem via nonsmooth equations method
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作者 郭修霞 《Journal of Coal Science & Engineering(China)》 2004年第1期109-111,共3页
A new nonsmooth equations model of constrained minimax problem was de-rived. The generalized Newton method was applied for solving this system of nonsmooth equations system. A new algorithm for solving constrained min... A new nonsmooth equations model of constrained minimax problem was de-rived. The generalized Newton method was applied for solving this system of nonsmooth equations system. A new algorithm for solving constrained minimax problem was established. The local superlinear and quadratic convergences of the algorithm were discussed. 展开更多
关键词 nonsmooth equations minimax problem generalized newton method nonsmooth optimization
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Modified Augmented Lagrange Multiplier Methods for Large-Scale Chemical Process Optimization 被引量:6
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作者 梁昔明 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2001年第2期167-172,共6页
Chemical process optimization can be described as large-scale nonlinear constrained minimization. The modified augmented Lagrange multiplier methods (MALMM) for large-scale nonlinear constrained minimization are studi... Chemical process optimization can be described as large-scale nonlinear constrained minimization. The modified augmented Lagrange multiplier methods (MALMM) for large-scale nonlinear constrained minimization are studied in this paper. The Lagrange function contains the penalty terms on equality and inequality constraints and the methods can be applied to solve a series of bound constrained sub-problems instead of a series of unconstrained sub-problems. The steps of the methods are examined in full detail. Numerical experiments are made for a variety of problems, from small to very large-scale, which show the stability and effectiveness of the methods in large-scale problems. 展开更多
关键词 modified augmented Lagrange multiplier methods chemical engineering optimization large-scale non- linear constrained minimization numerical experiment
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Bank Criminal Act: Case of Fraud Using Letter of Credit-Bank as a Victim
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作者 Pwee Leng Handjaya A. Hugan 《Chinese Business Review》 2018年第3期123-137,共15页
Letter of Credit (L/C) is a payment method offered by bank for settling the foreign trade. The existence of L/C is a means capable of providing guarantee for the interests of the sellers and buyers. In the event of ... Letter of Credit (L/C) is a payment method offered by bank for settling the foreign trade. The existence of L/C is a means capable of providing guarantee for the interests of the sellers and buyers. In the event of default by either party, either the seller or the buyer, the bank as the L/C issuer will provide payment guarantee for the seller or the waiver of payment for the buyer. The bank’s risk in issuing the L/C is regarding with the weakness of L/C. In Article 5 of UCP 600, it is emphasized that in transactions using L/C, banks deal only with documents, not dealing with goods, or other implementation. In Article 14a of UCP 600 it is affirmed that the L/C payments are based on the suitability between the L/C requirements and the submitted documents viewed under “on their face”. The bank authority as the guarantor which only deals with the documents in making payments causing the L/C instrument is often used in fraud against the bank. Many banking fraud cases that occur in Indonesia take advantage of L/C weakness. This paper will discuss the occurrence of criminal acts in the banking by exploiting weaknesses in the L/C that makes the bank as a victim. In addition, this paper aims to explain the effort to overcome the criminal acts that occurred at the issuing bank as a victim by using L/C. The discussion in this paper emphasized the application of laws and regulations applicable to indict the perpetrators of criminal acts in the banking sector by exploiting weaknesses of L/C. Aspects of the discussion of a criminal offense are based on the Act No. 10 of 1998 concerning banking, and under the provisions of the Criminal Code. 展开更多
关键词 Letter of Credit bank criminal act fraud against bank
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Stablility and Size Control of Silver Nanoparticles by Electrochemical Method
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作者 Sudad S. Ahmed Rawa K. Ibrahim +3 位作者 Asama N. Naje Kais A1-Naimee Abdulla A. Suhail Omar A.Ibrahim 《Journal of Physical Science and Application》 2016年第1期16-25,共10页
Silver nanoparticles (Ag-NPs) were prepared using an electrochemical technique. The optical properties were measured by absorption spectroscopy. The dimension of the prepared nanoparticles as estimated by the Atomic... Silver nanoparticles (Ag-NPs) were prepared using an electrochemical technique. The optical properties were measured by absorption spectroscopy. The dimension of the prepared nanoparticles as estimated by the Atomic Force Microscope (AFM), was 91.57 nm. This reaserch effort proposes a mechanism for reducing the size of silver nanoparticles by adding the hydrogen peroxide (H202), and protecting the silver nanoparticle to inhibit agglomeration by adding PVP polymer. 展开更多
关键词 Electrochemical method silver nanoparticles hydrogen peroxide PVP.
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仝小林因方施量策略探讨 被引量:4
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作者 彭智平 周强 +2 位作者 刘文科 郭允 赵林华 《中医杂志》 CSCD 北大核心 2012年第23期2002-2004,共3页
仝小林根据多年临床观察和实验研究,形成了系统的用量策略,其中因方施量乃是整体用量策略之一。因方施量策略具体包括根据制方大小决定用量和根据处方剂型决定用量,并由此提出了精方与围方的概念。因方施量策略总体而言:以制方大小而论... 仝小林根据多年临床观察和实验研究,形成了系统的用量策略,其中因方施量乃是整体用量策略之一。因方施量策略具体包括根据制方大小决定用量和根据处方剂型决定用量,并由此提出了精方与围方的概念。因方施量策略总体而言:以制方大小而论,精方用量偏大,围方用量平和;以处方剂型而论,汤剂用量最大,煮散用量相当于汤剂的1/2~1/3,丸、散(服散)、膏、丹剂型的用量相当于汤剂的1/10。制方大小与处方剂型既有联系又有区别,二者共同决定着处方的合理用量。 展开更多
关键词 大小 剂型 施量
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“用样方法调查草地中双子叶植物的种群密度”实验设计、实施与建议 被引量:5
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作者 肖崇德 王新 田树青 《生物学通报》 2016年第12期10-12,共3页
针对采用样方法调查草地中双子叶植物种群密度的探究实验,设计并实施了对3个不同生境地块中荠菜与车前草种群密度的估测,强调随机取样的重要性,并对调查对象的选择、教学课时的安排提出了教学建议。进一步探讨不同探究课题的确立,以及... 针对采用样方法调查草地中双子叶植物种群密度的探究实验,设计并实施了对3个不同生境地块中荠菜与车前草种群密度的估测,强调随机取样的重要性,并对调查对象的选择、教学课时的安排提出了教学建议。进一步探讨不同探究课题的确立,以及样方数目和大小与种群密度的关系,拓展了教学思路。 展开更多
关键词 种群密度 随机取样 数目 大小
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亚热带常绿阔叶林群落结构的空间变异及其对取样设计的启示 被引量:1
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作者 林敦梅 赖江山 +2 位作者 米湘成 任海保 马克平 《科学通报》 EI CAS CSCD 北大核心 2013年第1期69-74,共6页
基于24hm2森林监测样地的全面调查数据,评估了亚热带常绿阔叶林胸径截面积和地上生物量的空间变异性,并用计算机模拟不同面积的样方进行随机取样,计算了估计值有95%的概率落在实际值20%(±10%)的误差范围内所需要的最少样方个数和... 基于24hm2森林监测样地的全面调查数据,评估了亚热带常绿阔叶林胸径截面积和地上生物量的空间变异性,并用计算机模拟不同面积的样方进行随机取样,计算了估计值有95%的概率落在实际值20%(±10%)的误差范围内所需要的最少样方个数和总取样面积.结果表明:(1)胸径截面积和地上生物量均表现出显著的空间变异性,基于600个20m×20m网格样方,胸径截面积和地上生物量的变异系数分别为27%和31%;(2)计算机模拟取样发现随着样方面积的增大,两者的变异性都逐渐减小.满足特定精度所需的最少样方个数随着样方面积的增大而减少,但是总取样面积不断增加,这意味着达到相同的精度,采用满足一定数量的小样方进行取样的效率要高于采用少量的大样方.本研究结果可以为评估过去在中国亚热带森林开展的相关研究以及今后野外调查的取样设计提供参考. 展开更多
关键词 空间变异 胸径截面积 地上生物量 大小 取样个数
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