The relationship of the estimated former burial depth of the lower Oxford Clay to some soil properties

Author(s):  
J. O. Jackson ◽  
P. G. Fookes
1966 ◽  
Vol 46 (2) ◽  
pp. 155-160 ◽  
Author(s):  
G. R. Saini ◽  
A. A. MacLean ◽  
J. J. Doyle

The relationship of the mean weight diameter of water-stable aggregates to certain soil properties (clay, organic matter, free iron, free aluminum, and polysaccharide contents) and the relationship of the increase in aggregation caused by VAMA to the same properties of 24 New Brunswick soils were evaluated by correlation and regression analyses.Simple correlation coefficients relating aggregation to soil properties indicated that organic matter (r = 0.627), polysaccharides (r = 0.602), and aluminum (r = 0.679) were the most important factors. However, when the influence of each factor was separated by partial correlation, the coefficients were not significant. On the other hand, the combined effects of all factors as indicated by the multiple correlation coefficient (r = 0.743) was significant at the 1% level. The effect of the same soil properties on response to VAMA, as shown by increase in mean weight diameter, indicated that clay exerted the greatest influence. The relationship with other factors was nonsignificant.


2020 ◽  
Vol 3 (2) ◽  
pp. 51-55
Author(s):  
Muhammad Yakub ◽  
M. Faiz Barchia ◽  
Usman K.J. Suharjo

Salak (Zalacca edulis Gaertn. Voss) is one of the most populair native fruits of Indonesia, consumed as a table fruit by most Indonesians. However, the yield of salak pondoh grown in Bengkulu is still lower than that in their native soil Java, believed to have more suitable soil properties for growing salak pondoh. The objective of this research were to evaluate the relationship of soil bulk density, available K, and slope to the productivity of salak pondoh grown at Padang Jaya Regency, North Bengkulu. We did a survey to collect data on soil bulk density (BD), available K (K), and slope as well as the productivity of salak pondoh grown at Padang Jaya from November 2017 to May 2017. The results showed that there was a significant relationship between soil characteristics and salak productivity, as shown in a linear model of Y = 2.929 -1.070 BD + 0.069 K - 0.126 Slope. Soil K was positively correlated to salak productivity, suggesting that salak productivity increased with an increase in soil K.  On the other than, soil bulk density and slope were negatively correlelated to salak productivity, indicating that salak productity decreased with an increase in slope and in soil bulk density.


2016 ◽  
Vol 51 (1) ◽  
Author(s):  
K. Kalyani ◽  
V. Sailaja ◽  
P. Chandrasekhar Rao

Exploring the relationship among inorganic potassium fractions, yield and soil properties were important to know the best extractant for available K for cauliflower in the light textured soils of Rangareddy district. Surface soils in bulk were collected from thirty locations of Rangareddy district and pot culture experiment was carried out. Inorganic K fractions were analysed to evaluate the relative efficiency of extractants in determining the available K. Here, we have investigated the relationships among the soil properties, between soil properties and K uptake, between soil properties and yield, between K fractions and K uptake, between K fractions and yield. Organic carbon (r = 0.65**), available nitrogen (r = 0.60**) exhibited a significant positive correlation with NH4OAc (1N) extractable K. Available potassium extracted by NH4OAc showed a significant positive correlation with NaBPh4 (0.2 M) extractable K (r = 0.93**), 1M HNO3 (r = 0.55**) and also with citric acid extractable K (r = 0.67**). Among all the extractants 1N NH4OAc extractable K showed higher positive correlation with curd yield (r = 0.975**). It had a significant positive correlation with NaBPh4 (0.2 M) extractable K (r = 0.926**).


2021 ◽  
pp. 163-175
Author(s):  
V. I. Savich ◽  
V. V. Gukalov ◽  
A. E. Sorokin ◽  
M. D. Konakh

This paper assesses the relationship between the physico-chemical and agro-chemical properties of sod-podzolic soils in the Moscow region and ordinary heavy-loamy chernozems in the Krasnodar region within the catenas and down the soil profile. Soil properties changed significantly through seasonal dynamics. From the end of April to the middle of June in the soil solution of sod-podzolic soils, the value of Eh varied from 534 to 759 mv, the ratio of NO3/NH4 – from 0.2 to 15.4; the content of water-soluble manganese – from 4.0 to 10.1. At the same time, there was a delay in change of soil properties, as humidity and temperature varied. It is shown that in different intervals of soil properties between individual indicators of fertility, the effects of synergism and antagonism are manifested. The degree of mutual influence of soil properties depended on both the degree of soil fertilization and the degree of their cultivation. Information relationships were manifested not only between the soil properties, but also between the processes. Temporary excessive moistening of the soil led to acidification of the soil in the washing type of water mode, and to alkalinization in the non-washing type. It is proposed to account for the relationship of soil properties with humidity, temperature, pH, and Eh to adjust the components of farming systems.


Paleobiology ◽  
1980 ◽  
Vol 6 (02) ◽  
pp. 146-160 ◽  
Author(s):  
William A. Oliver

The Mesozoic-Cenozoic coral Order Scleractinia has been suggested to have originated or evolved (1) by direct descent from the Paleozoic Order Rugosa or (2) by the development of a skeleton in members of one of the anemone groups that probably have existed throughout Phanerozoic time. In spite of much work on the subject, advocates of the direct descent hypothesis have failed to find convincing evidence of this relationship. Critical points are:(1) Rugosan septal insertion is serial; Scleractinian insertion is cyclic; no intermediate stages have been demonstrated. Apparent intermediates are Scleractinia having bilateral cyclic insertion or teratological Rugosa.(2) There is convincing evidence that the skeletons of many Rugosa were calcitic and none are known to be or to have been aragonitic. In contrast, the skeletons of all living Scleractinia are aragonitic and there is evidence that fossil Scleractinia were aragonitic also. The mineralogic difference is almost certainly due to intrinsic biologic factors.(3) No early Triassic corals of either group are known. This fact is not compelling (by itself) but is important in connection with points 1 and 2, because, given direct descent, both changes took place during this only stage in the history of the two groups in which there are no known corals.


Author(s):  
D. F. Blake ◽  
L. F. Allard ◽  
D. R. Peacor

Echinodermata is a phylum of marine invertebrates which has been extant since Cambrian time (c.a. 500 m.y. before the present). Modern examples of echinoderms include sea urchins, sea stars, and sea lilies (crinoids). The endoskeletons of echinoderms are composed of plates or ossicles (Fig. 1) which are with few exceptions, porous, single crystals of high-magnesian calcite. Despite their single crystal nature, fracture surfaces do not exhibit the near-perfect {10.4} cleavage characteristic of inorganic calcite. This paradoxical mix of biogenic and inorganic features has prompted much recent work on echinoderm skeletal crystallography. Furthermore, fossil echinoderm hard parts comprise a volumetrically significant portion of some marine limestones sequences. The ultrastructural and microchemical characterization of modern skeletal material should lend insight into: 1). The nature of the biogenic processes involved, for example, the relationship of Mg heterogeneity to morphological and structural features in modern echinoderm material, and 2). The nature of the diagenetic changes undergone by their ancient, fossilized counterparts. In this study, high resolution TEM (HRTEM), high voltage TEM (HVTEM), and STEM microanalysis are used to characterize tha ultrastructural and microchemical composition of skeletal elements of the modern crinoid Neocrinus blakei.


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