FERTILITY GROUPING OF MONTREAL LOWLANDS SOIL MAPPING UNITS BASED ON SELECTED SOIL CHARACTERISTICS OF THE PLOW LAYER

1989 ◽  
Vol 69 (3) ◽  
pp. 525-541 ◽  
Author(s):  
M. C. NOLIN ◽  
C. WANG ◽  
M. J. CAILLIER

Ten soil properties, including texture, pH, available phosphorous, cation exchange capacity, exchangeable cations and organic carbon, were determined from the Ap horizons of 91 map units of two Montreal Lowlands counties. Multivariate analysis techniques were used to classify the soils into fertility groups. Nine fertility groups were derived from cluster analysis. Principal component analysis yielded two components which accounted for more that 75% of the variance. These principal components were related to soil texture and fertilizer management factors. They confirmed the grouping obtained by cluster analysis. Multiple discriminant analysis distinguished these fertility groups and allocated new soil mapping units to one of them using discriminant functions. Clay content, pH, exchangeable Ca and available P were selected as the more potent and significant variables in descriminating groups. This work demonstrated that multivariate analysis has considerable promise in deriving meaningful interpretive grouping from selected soil parameters. Key words: Fertility, interpretive grouping, soil quality, multivariate analysis

2006 ◽  
Vol 131 (6) ◽  
pp. 770-779 ◽  
Author(s):  
Santiago Pereira-Lorenzo ◽  
María Belén Díaz-Hernández ◽  
Ana María Ramos-Cabrer

Morphological characters (six traits) and isozymes (four systems, five loci) were used to discriminate between Spanish chestnut cultivars (Castanea sativa Mill.) from the Iberian Peninsula. A total of 701 accessions (representing 168 local cultivars) were analyzed from collections made between 1989 and 2003 in the main chestnut growing areas: 31 were from Andalucía (12 cultivars), 293 from Asturias (65 cultivars), 25 from Castilla-León (nine cultivars), four from Extremadura (two cultivars) and 348 from Galicia (80 cultivars). Data were synthesized using multivariate analysis, principal component analysis, and cluster analysis. A total of 152 Spanish cultivars were verified: 58 cultivars of major importance and 94 of minor importance, of which 18 had high intracultivar variation. Thirty-seven cultivars were clustered into 14 synonymous groups. Six of these were from Galicia, one from Castilla-León (El Bierzo), four from Asturias, one from Asturias and Castilla-León (El Bierzo), and two from Asturias, Castilla-León (El Bierzo), and Galicia. The chestnut cultivars from Galicia and Asturias were undifferentiated in genetic terms, indicating that they are not genetically isolated. Overall, chestnut cultivars from southern Spain showed the least variation. Many (58%) of Spanish cultivars produced more than 100 nuts/kg; removing this low market-value character will be a high priority. The data obtained will be of use in chestnut breeding programs in Spain and elsewhere.


1998 ◽  
Vol 20 (1) ◽  
pp. 119 ◽  
Author(s):  
B Fergusson ◽  
AJ Graham

The soil and plants at a 27.4 ha field site near Kalgoorlie, Western Australia, were surveyed and analysed with multivariate statistics. Cluster analysis identified four distinct plant communities at the study site. These were: Acacia acuminata shrubland Eucalyptus gvfithsii woodland Eucalyptus salrnonophloia woodland 'Ground Covers' - areas characterised by the presence of generalist herbs, low shrubs and weeds, and the absence of dominant upper storey species. Discriminant function analysis identified site elevation and soil exchangeable Ca as the primary environmental discriminants between the plant communities. Using these two variables, sample points were classified into one of the four plant communities. The two methods of classification matched well, with classification based on the two environmental variables providing an indication of which plant community would be most likely to establish in disturbed areas. This type of information can be important to revegetation programs in the region, guiding the use of appropriate plant species under different rehabilitation conditions. Key wcrds: environmental variables, plant communities, multivariate analysis, classification, revegetation


2019 ◽  
Vol 43 (2) ◽  
pp. 151-159
Author(s):  
Huseyin Inceer ◽  
Murat Bal

In the Turkish flora, the genus Matricaria is present with four taxa, namely M. aurea, M. chamomilla var. chamomilla, M. chamomilla var. recutita and M. matricarioides. This study presents an evaluation of selected diagnostic characters and anatomical traits of the achene (cypsela) of Matricaria in Turkey using univariate analysis (one-way analysis of variance) and multivariate analysis (cluster analysis, principal component analysis) to obtain new information. Three groups are found within the genus Matricaria based on morphoanatomical characteristics. The colour of disc florets, that of ribs on the achenes, the presence or absence of a slime envelope and pericarp thickness are useful for delimitation of Matricaria taxa, and a key to taxa based on these characters together with other diagnostic traits is provided.


Soil Research ◽  
1988 ◽  
Vol 26 (2) ◽  
pp. 243 ◽  
Author(s):  
G Atkinson

The techniques of cluster analysis and principal component analysis (PCA) were applied to soils data from two Pleistocene alluvial terraces on the Nepean River, N.S.W., the Clarendon and Cranebrook Formations, to address issues raised in the literature regarding their stratigraphic relationships. A total of 160 profiles were sampled at four fixed depths to 1 8 m. Profiles were located in four 1000 by 400 m sample areas, two on each terrace. Soil samples were analysed for colour, pH, and 2.8 M HCl extractable Fe2+, Mn2+, Na2+, K+, Ca2+ and Mg2+. Data were analysed by using whole profiles as the soil entities. One branch of the dendrogram resulting from the cluster analysis contained soil profiles exclusively from sample areas on the Cranebrook Formation, whilst the other branch contained profiles exclusively from sample areas on the Clarendon Formation. Soils typical of the Lowlands Formation, Londonderry Clay and minor subdivisions within the terraces could be distinguished on the dendrogram. Similar subdivisions could also be observed on a PCA scattergram. The Clarendon and Cranebrook Formations are complex units which contain minor terrace features. Each has a distinctly different suite of soils which is consistent with their continued designation as separate stratigraphic units. The Lowlands Formation can be separated from the Cranebrook Formation upstream of Castlereagh and the Clarendon Formation should have its southern boundary to the Londonderry Clay moved north towards Richmond and its stratigraphy redefined.


2013 ◽  
Vol 15 (2) ◽  
pp. 179
Author(s):  
Admir Antonio Betarelli Junior ◽  
Roberto Luís De Melo Monte-Mór ◽  
Rodrigo Ferreira Simões

O propósito deste trabalho é discutir a formação, produção e organização do espaço urbano no estado de São Paulo a partir do processo de interiorização da indústria paulista no final dos anos 1970. O lócus da análise é a indústria, uma vez que no enfoque contemporâneo o processo de industrialização sempre esteve articulado com a produção da espacialidade urbana. Conciliando o método diferencial-estrutural (shift-share), a Análise de Componentes Principais (ACP) e a análise de cluster, foi possível evidenciar que tal processo teve como resultado o fenômeno de urbanização extensiva. Os resultados “fotográficos” apontam que houve uma extensão virtual das condições gerais do tecido urbano-industrial de forma que centralidades polarizadoras e regiões circunvizinhas apresentam vantagens locacionais e competitivas, formando, assim, aglomerações urbanas no território paulista, principalmente, nas regiões beneficiadas pelo processo de interiorização da indústria. Palavras-chave: urbanização extensiva; análise multivariada; análise de cluster; método diferencial-estrutural; indústria; São Paulo. Abstract: The main aim of this paper is to discuss the formation, organization and production of urban areas in State of São Paulo (Brazil) in the variant of the process of industry’s internalization in the late ‘70s. As industrialization has always been linked to the production of urban spatiality in contemporary approach, the locus of analysis is the industry. Combining the method shift-share (Esteban-Marquillas), Principal Component Analysis (PCA) and cluster analysis, we noted evidence that this process has resulted in the phenomenon of extensive urbanization. The main findings of these applications (“photographic”) indicated that there was a virtual extension in general conditions of the urban-industrial fabric so that polarizing centralities and surrounding regions present locational and competitive advantages, forming, therefore, urban agglomerations in the territory of São Paulo, mainly in the regions benefiting with the process of industry’s internalization. Keywords: extensive urbanization; internalization of the industry; shift-share; multivariate analysis; São Paulo (Brazil).


Author(s):  
Berk Benlioglu ◽  
Ugur Ozkan

Background: Mungbean [Vigna radiata (L.) Wilczek] is known as one of the important crop of the Vigna group. In order to determine morphological traits of mungbean, multivariate analysis will provide important advantages in the selection phase of future breeding programs. Multivariate statistical analysis was used to determine and classify these traits. Multivariate analysis, that includes principal component analysis (PCA) and cluster analysis (CA), is considered the best tool for selecting promising genotypes in the future breeding programs. Methods: Eighteen landraces and two species were used to classify morphological traits in this study. Nine different morphological traits were observed during the research period. These are; days to 50% flowering (DFT), plant height (PH), branches per plant (BPP), clusters per plant (CPP), number of pods per cluster (PPC), seed yield per plot (SYPP), biomass yield per plot (BYPP), harvest index (HI), 1000 seed weight (SW). Result: Principal component analysis (PCA) revealed a high level of variation among the genotypes. Therefore, high variability was observed in DFT (36-59 day), PH (39-76 cm), BPP (3-7), CPP (4-21), SYPP (231-824 g), BYPP (3300-10300 g), HI (6.77-11.25%) and 1000 SW (19.95-50.50 g). According to cluster analysis, landraces with the least genetic diversity distance between them in terms of morphological traits examined were determined as 2 and 3.


Soil Research ◽  
1993 ◽  
Vol 31 (4) ◽  
pp. 437 ◽  
Author(s):  
IP Little

This paper has two components. Firstly it evaluates a set of data for the apple-growing soils of the Batlow district. Secondly it makes some comments on the use of silver thiourea for the determination of exchangeable Al and Mn and the estimation of exchangeable Al by titration of 1 M KCl suspensions. A group of 21 profiles from soils used for apple-growing in the Batlow District were examined in the laboratory. It was found that many of the soils were very acidic, especially in the subsoil. Dilute CaCl2 extracted as much as 50 �g g-1 of Al and considerable exchangeable Al was extracted by silver thiourea. Exchangeable Ca levels were usually adequate for plant growth, hence low levels in apple fruit may reflect the adverse effect of Al on Ca uptake by the plant. Potassium levels were low and may be marginal in some cases and Mg tended to be low in the surface. Principal component analysis showed 77% of the variation in the data was accounted for by three independent components, one involving pH, exchangeable Ca and Al, one involving K and Mg and one involving exchangeable Mn. It was demonstrated that silver thiourea does not replace Al as effectively as the basic exchangeable cations. Also, thiourea reduces Mn so that low values will be obtained for exchangeable Al in soils with much easily reducible Mn because of the increase in pH that accompanies reduction. Silver thiourea appears to overestimate exchangeable Al in some soils with very low cation exchange capacity. Titration of clay suspensions in 1 M KCl is a satisfactory and reliable way of measuring exchangeable Al that also enables an assessment of pH-dependent charge. The method used by the USDA Soil Survey Staff, viz. equilibration of soil samples with 1 M KCl for 16 h, filtration, and determination of Al also gives reproducible results and is taken as the standard. Successive leaching with portions of 1 M KCl tends to give low values for exchangeable Al.


2017 ◽  
Vol 9 (3) ◽  
pp. 219
Author(s):  
Ramesh Kumar ◽  
G. K. Chikkappa ◽  
S. B. Singh ◽  
Ganapati Mukri ◽  
J. Kaul ◽  
...  

Crop yields of major cereal including maize are not increasing at the targeted growth rates to feed the rising demands stemming from increase in the human population. To increase maize grain yield, there should be continuous improvement of cultures which are actively utilized by the plant breeders. Variability in germplasm is always the key to improvement and to assess the extent of variation is never ending process in a plant breeding program. Out of several methods available for assessing the variability, multivariate analysis is one of the most important and widely used methods. In the present study, 27 hybrids (including three checks) were evaluated for yield and yield contributing traits at three different locations during rabi 2013-14. Analysis of variance revealed significant variations among hybrids for all the traits. Based on Principal Component Analysis, 76.81% of the total variance in the data was accounted for by first four principal components (PC). Cluster analysis based on PC grouped the 27 hybrids into two major groups named as A and B. The group A further contained three sub-groups named as A1, A2, and A3 with two hybrids falling in each group. Similarly group B contained four subgroups classified as B1 to B4 with 2, 7, 5 and 7 hybrids falling in each subgroup respectively. The hybrids falling in two major groups contained more diversity than those falling in subgroups within a group. Selection of hybrids from the different groups would facilitate exploiting significant heterosis. Therefore, multivariate analysis including Principal component analysis followed by cluster analysis could be a reliable approach for assessing the extent of variability on in the germplasm and making its use in a suitable direction.


2019 ◽  
Vol 41 (2) ◽  
pp. 180-186
Author(s):  
Jéssica de Lucena Marinho ◽  
Denis Santiago da Costa ◽  
Deived Uilian de Carvalho ◽  
Maria Aparecida da Cruz ◽  
Claudemir Zucareli

Abstract: Evaluation of the physiological potential of seeds by fast and efficient methods is an important step in the process of production and commercialization of sweet corn seeds. The aim of this study was to discriminate sweet corn seed lots by applying multivariate methods regarding the usual vigor tests to verify the sensitivity of these seeds to flood conditions and to verify if the submersion test has potential for classifying lots of this species regarding vigor. Five seed lots of sweet corn were tested for moisture content and physiological potential. Cluster analysis and principal component analysis were performed on the data to discriminate the seed lots regarding initial vigor. Subsequently, two of these lots were selected for the water submersion test, performed with four replicates of 150 seeds, which were submerged in 100 mL of distilled water for 0, 24, 48, 72, and 96 hours at 25 ºC, and they then underwent the germination test. Discrimination of sweet corn seed lots is possible through multivariate analysis. Sweet corn seeds are sensitive to submersion in water; however, the test did not allow seed lots to be differentiated for vigor.


Sign in / Sign up

Export Citation Format

Share Document