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辽北地区气象条件对大豆产量的影响 被引量:2
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作者 林晓新 郭奥楠 《农业开发与装备》 2017年第4期40-41,共2页
辽北地区是辽宁省大豆主产区,从历史资料看,大豆产量波动很大,直接影响着大豆生产的发展。近年来随着生产水平的提高,我们国家对大豆的栽培技术投入加大,研究开发的大豆新品种层出不穷,生产措施不断完善,大豆产量也有较大地提高,但由于... 辽北地区是辽宁省大豆主产区,从历史资料看,大豆产量波动很大,直接影响着大豆生产的发展。近年来随着生产水平的提高,我们国家对大豆的栽培技术投入加大,研究开发的大豆新品种层出不穷,生产措施不断完善,大豆产量也有较大地提高,但由于气候变化的不稳定,大豆产量的波动幅度也增大。为了找出影响大豆产量波动的主要原因,利用计算机客观地分析大豆高产的气象因素,以我们掌握的辽宁北部六县(铁岭、开愿、昌图、西丰、法库、康平)1965—2009年原始数据的为依据,对大豆产量和气象条件的相关计算和回归分析,探讨大豆产量与热、水、光等气象条件的基本关系,研究产量波动的实质、关键时期、影响程度及地域变化规律,为合理有效利用气候资源,科学的设计农艺措施,进一步促进大豆高产、稳产提供科学依据。 展开更多
关键词 辽北地区气象 大豆产量分析 结论分析
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Multivariate Regression Analysis on Correlated Characters about Fresh Pod Yield of Fresh Edible Soybean
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作者 葛长军 闫良 +1 位作者 徐丽荣 罗九玲 《Agricultural Science & Technology》 CAS 2015年第4期687-690,共4页
Objective] The alm was to survey 10 characters of 8 fresh edibIe soy-bean varieties, analyze maln Ioading factors using principal component analysis, and estabIish muItipIe regression equation on fresh pod yield. [Met... Objective] The alm was to survey 10 characters of 8 fresh edibIe soy-bean varieties, analyze maln Ioading factors using principal component analysis, and estabIish muItipIe regression equation on fresh pod yield. [Methods] Through princi-pal component analysis on 10 characters of 8 fresh edibIe soybean varieties, char-acters reIated to fresh pod yield of fresh edibIe soybean were cIarified. [Results] Af-ter the principal components analysis, pod weight per pIant, 100-seed weight and pod number per pIant of fresh edibIe soybean were chosen to study their reIation with the yield of fresh edibIe soybean, moreover, it was demonstrated that the reIa-tion was Iinear reIation, thus it was suitabIe for muItivariate regression analysis. Fi-nal y, the mathematical expression formuIa about fresh pod yield was estabIished. [Conclusions] There were three characters affecting fresh pod yield, nameIy, pod weight per pIant, 100-seed weight and pod number per pIant, the mathematical equation was y=816.732+4.145X6-0.718X8-0.985X9 (X6: pod weight per pIant; X8: 100-seed weight; X9: pod number per pIant). 展开更多
关键词 Fresh edible soybean Fresh pod yleId Principal component analysis MuItiple regresslon equatlon
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Minimum Data Set for Assessing Soil Quality in Farmland of Northeast China 被引量:18
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作者 CHEN Yu-Dong WANG Huo-Yan +4 位作者 ZHOU Jian-Min XING Lu ZHU Bai-Shu ZHAO Yong-Cun CHEN Xiao-Qin 《Pedosphere》 SCIE CAS CSCD 2013年第5期564-576,共13页
Soil quality assessment provides a tool for agriculture managers and policy makers to gain a better understanding of how various agricultural systems affect soil resources. Soil quality of Hailun County, a typical soy... Soil quality assessment provides a tool for agriculture managers and policy makers to gain a better understanding of how various agricultural systems affect soil resources. Soil quality of Hailun County, a typical soybean (Glycine max L. Merill) growing area located in Northeast China, was evaluated using soil quality index (SQI) methods. Each SQI was computed using a minimum data set (MDS) selected using principal components analysis (PCA) as a data reduction technique. Eight MDS indicators were selected from 20 physical and chemical soil measurements. The MDS accounted for 74.9% of the total variance in the total data set (TDS). The SQI values for 88 soil samples were evaluated with linear scoring techniques and various weight methods. The results showed that SQI values correlated well with soybean yield (r = 0.658**) when indicators in MDS were weighted by the regression coefficient computed for each yield and index. Stepwise regression between yield and principal components (PCs) indicated that available boron (AvB), available phosphorus (AvP), available potassium (AvK), available iron (AvFe) and texture were the main factors limiting soybean yield. The method used to select an MDS could not only appropriately assess soil quality but also be used as a powerful tool for soil nutrient diagnosis at the regional level. 展开更多
关键词 norm value principal component analysis soil quality index stepwise regression
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