An examination of the wet aggregate analysis, the moisture characteristic, and infiltration-percolation methods of determining the stability of soil aggregates

Soil Research ◽  
1972 ◽  
Vol 10 (1) ◽  
pp. 15 ◽  
Author(s):  
N Collis-George ◽  
KB Laryea
Keyword(s):  
Structural Stability ◽  
Soil Aggregates ◽  
High Energy ◽  
Characteristic Method ◽  
Analysis Method ◽  
Flood Irrigation ◽  
Aggregate Analysis ◽  
Moisture Characteristic ◽  
The Stability

Four methods of assessing structural stability of aggregates which employ different disruptive forces have been examined. Sorptivity (Philip 1957) has been demonstrated to be a useful method of assessing structural stability of soils during infiltration. The results obtained are consistent with those using either the high energy moisture characteristic method of Childs (1940, 1942), the wet aggregate analysis method of Quirk (1950), and the qualitative slaking-dispersion classification of aggregates proposed by Emerson (1967). Using these four methods, one soil was classified as stable, and two unstable to flood irrigation, whereas conventional chemical definitions did not distinguish unequivocally between them.

scholarly journals Aggregate stability by the "high energy moisture characteristic" method in an oxisol under differentiated management

2014 ◽  
Vol 38 (5) ◽  
pp. 1633-1642 ◽  
Author(s):  
Érika Andressa da Silva ◽  
Geraldo César de Oliveira ◽  
Bruno Montoani Silva ◽  
Carla Eloize Carducci ◽  
Junior Cesar Avanzi ◽  
...  
Keyword(s):  
Soil Aggregates ◽  
Aggregate Stability ◽  
Soil Surface ◽  
Stability Index ◽  
Tropical Soils ◽  
High Energy ◽  
Stability Parameters ◽  
Aggregation State ◽  
Moisture Characteristic ◽  
The Stability

Studies testing the High Energy Moisture Characteristic (HEMC) technique in tropical soils are still incipient. By this method, the effects of different management systems can be evaluated. This study investigated the aggregation state of an Oxisol under coffee with Brachiaria between crop rows and surface-applied gypsum rates using HEMC. Soil in an experimental area in the Upper São Francisco region, Minas Gerais, was studied at depths of 0.05 and 0.20 m in coffee rows. The treatments consisted of 0, 7, and 28 Mg ha-1 of agricultural gypsum rates distributed on the soil surface of the coffee rows, between which Brachiaria was grown and periodically cut, and compared with a treatment without Brachiaria between coffee rows and no gypsum application. To determine the aggregation state using the HEMC method, soil aggregates were placed in a Büchner funnel (500 mL) and wetted using a peristaltic pump with a volumetric syringe. The wetting was applied increasingly at two pre-set speeds: slow (2 mm h-1) and fast (100 mm h-1). Once saturated, the aggregates were exposed to a gradually increasing tension by the displacement of a water column (varying from 0 to 30 cm) to obtain the moisture retention curve [M = f (Ψ) ], underlying the calculation of the stability parameters: modal suction, volume of drainable pores (VDP), stability index (slow and fast), VDP ratio, and stability ratio. The HEMC method conferred sensitivity in quantifying the aggregate stability parameters, and independent of whether gypsum was used, the soil managed with Brachiaria between the coffee rows, with regular cuts discharged in the crop row direction, exhibited a decreased susceptibility to disaggregation.

The use of high energy moisture characteristic to assess soil stability

Soil Research ◽  
1984 ◽  
Vol 22 (3) ◽  
pp. 349 ◽  
Author(s):  
N Collis-George ◽  
BS Figueroa
Keyword(s):  
Aggregate Stability ◽  
High Energy ◽  
Laboratory Method ◽  
Soil Stability ◽  
Structural Index ◽  
Quick Method ◽  
Stability Ratio ◽  
Moisture Characteristic ◽  
The Stability ◽  
Structural Indices

The laboratory method of determining aggregate stability introduced by Childs in 1940 is reconsidered. A convenient and quick method of interpreting the experimental results is presented and provides the structural index for a given soil treatment. The ratio of the structural indices for two soil treatments provides the stability ratio, which is of relevance to erosion and pedogenetic studies of structure. Illustrative results show that pretreatments such as air drying, grinding and sieving affect the structural index and stability ratio.

ESTIMATION OF TECHNICAL, SPECIALIZED AND ECONOMIC EFFICIENCY OF CULTIVATED POTATO VARIETIES USING DATA ENVELOPE ANALYSIS METHOD (DEA) IN IRAQ FOR SPRING LUG 2018

2020 ◽  
pp. 119-131
Keyword(s):  
Technical Efficiency ◽  
Economic Efficiency ◽  
Potato Crop ◽  
Economic Status ◽  
Analysis Method ◽  
Envelope Analysis ◽  
Variable Capacity ◽  
Data Envelope Analysis ◽  
Using Data ◽  
The Stability

Research highlights the importance of potato crop, which occupies a prominent food and economic status in food security besides rice, wheat and corn at the local and global level. Despite the expansion of the cultivation of potato crop in Iraq in general and Ameriyah district in particular However, potato productivity remains substandard, this may be due to a lack of knowledge of the most efficient varieties and not to use productive resources at the levels at which technical, specialized and economic efficiency is achieved. Therefore, the aim of the research is to determine the technical, specialized and economic efficiency according to the cultivated seed category. The data envelope analysis (DEA) method was used to estimate technical, specialized and economic efficiency, assuming constant and variable capacity returns. As a result of the study, the Safrana variety achieved the highest average technical efficiency according to the stability of the yield and capacity efficiency in addition to achieving the highest average specialized and economic efficiency, The Lapadia variety achieved the highest average technical efficiency, assuming that capacity returns have changed. Therefore, we recommend the adoption of items that achieve higher efficiency and the need to redistribute the elements of production better and Achieving the optimum levels at which technical, specialized and economic efficiency is achieved and saving what has been wasted.

Influence of internal and external risks on sustainability of financial system of Аltai krai

2018 ◽  
Vol 35 (4) ◽  
pp. 133-136
Author(s):  
R. N. Ibragimov
Keyword(s):  
Sustainable Development ◽  
Financial Stability ◽  
Management Strategy ◽  
Financial System ◽  
Risk Management Strategy ◽  
The Sustainable Development ◽  
The Stability ◽  
The Impact

The article examines the impact of internal and external risks on the stability of the financial system of the Altai Territory. Classification of internal and external risks of decline, affecting the sustainable development of the financial system, is presented. A risk management strategy is proposed that will allow monitoring of risks, thereby these measures will help reduce the loss of financial stability and ensure the long-term development of the economy of the region.

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