scholarly journals Origin and Dynamics of Termite Mound Soils in Southern India

2021 ◽  
pp. 19-23
Author(s):  
A. K. Harit ◽  
P. Jouquet

Aims: In Southern India, termite above-ground nests can have the shape of cathedral (CAT) or lenticular (LENT) mounds. Although CATare built by the fungus-growing species Odontotermes obesus, the origin and evolution of LENT remain unknown. Therefore, the aim of to study was to estimate the origin and dynamics of LENT from their specific physical and chemical properties. Study Site: This study was carried out in the Bandipur Tiger reserve (dry deciduous forest), Karnataka, Southern India. Methodology:  All the soil samples were collected in a Fluvisol in the Mule Hole experimental watershed.Only large size mounds between 1.5 - 1.8m high were considered in this study. Soil samples were collected from the outer wall of CATnest and from the soil surface layer (0-5 cm deep) and surrounding soil. Particle-size distribution and dispersion were obtained by process of sedimentation. All the statistical analysis such as principal component analysis (PCA) were calculated using R studio and R version 3.2.1. Results: Using elemental physical and chemical properties, this study showed a gradient of soil properties from the soil sampled between 50-100 cm depth to CAT, LENT and the surrounding topsoil (CTRL, Fluvisol), suggesting that: (i) CAT can be considered patches in the landscapes with specific physical and chemical properties in comparison with CTRL and LENT; (ii) LENT mounds can result from the progressive modification of CTRL (autogenic origin of LENT) and their degradation leads to a progressive recovery of CTRL properties or (iii) they originate from the colonization of abandoned CAT by other termite species (exogenic origin of LENT). Conclusion: This study confirms the complexity of CAT and LENT fates and the need for long-term datasets to determine the origin and evolution of termite mounds.

2011 ◽  
Vol 3 (5) ◽  
pp. 37-42
Author(s):  
Renata Mikalauskienė ◽  
Donatas Butkus ◽  
Ingrida Pliopaitė Bataitienė

The present article describes changes in specific activities and fluctuations in the ratio of natural 40K and artificial 137Cs radionuclides in soil samples taken from different places of Lithuanian territory. The samples of soil have been selected from the districts polluted after the accident in Chernobyl nuclear plant performing nuclear testing operations. The study has established the main physical and chemical properties of soil samples and their impact on the concentration of 40K activities. 137Cs/40K specific activities in soil have been observed under the dry weight of the sample that varied from 0.0034 to 0.0240. The results of the study could be used for establishing and estimating 137Csand 40K transfer in the system “soil-plant”. Santrauka Straipsnyje nagrinėjama gamtinės (40K) ir dirbtinės (137Cs) kilmės radionuklidų savitųjų aktyvumų ir jų santykio kaita skirtinguose Lietuvos teritorijos dirvožemiuose. Dirvožemio mėginiai parinkti iš vietovių, kurios buvo labiau užterštos po Černobylio atominės elektrinės avarijos ir buvusių branduolinių bandymų. Tyrimo metu nustatytos pagrindinės fizinės cheminės dirvožemio savybės ir jų poveikis 40K aktyvumų koncentracijai. 137Csir 40K savitieji aktyvumai dirvožemyje tirti esant sausam mėginio svoriui. 137Cs savitieji aktyvumai sausame dirvožemyje svyravo nuo 1,1±1,0 iki 14,3±0,9 Bq/kg, o 40K savitieji aktyvumai – nuo 326±29 iki 740±15 Bq/kg. 137Csir 40K savitųjų aktyvumų santykis skirtingų vietovių dirvožemiuose kito nuo 0,0034 iki 0,0240 Bq/kg. Tyrimo rezultatai gali būti panaudoti, nustatant ir įvertinant 137Csir 40K pernašą sistemoje dirvožemis–augalai.


2019 ◽  
Vol 35 (4) ◽  
Author(s):  
Willian Barros Nascimento ◽  
Milton César Costa Campos ◽  
Bruno Campos Mantovanelli ◽  
Luís Antônio Coutrim dos Santos ◽  
José Mauricio Cunha ◽  
...  

The Amazon region has a great diversity of landscapes such as forests galleries, natural fields (“Cerrados Amazônicos”), dense forest, these environments made possible the formation of a broad class of soils over time. The aim of this study was to evaluate the physical and chemical properties of soils in different physiographic environments in southern Amazonas, Brazil. Three areas of representative physiographies were selected, all of them in natural conditions: natural field / forest and floodplain / dry land transitions, and corrugated relief areas. Soil samples were collected in layers of 0.0 to 0.20 and 0.80-1.0 m. From the samples collected the following physical analyzes were performed: particle size, bulk density, particle density, total porosity and saturated hydraulic conductivity; and chemical: exchangeable calcium, magnesium, aluminum and potassium available, phosphorus, potential acidity, pH and organic carbon. Based on the results of chemical analysis were calculated the sum of bases and base saturation. The results were submitted to multivariate statistics analysis, at the discretion of the principal component analysis (PCA). From the results it is clear that different physiographic environments studied influence the formation of different soil classes, featuring the diversity of Amazonian soils. The PCA allowed the distinction and formation of different similarity groups, thus enabling to relate the physical and chemical properties with the physiographic formation in which they are inserted.


Author(s):  
Landing Biaye ◽  
Fary Diome ◽  
Seybatou Diop ◽  
Modou Mbaye ◽  
Djibril Tine ◽  
...  

The locality of Nioro du Rip is facing intense erosion, loss of agricultural land, soil pollution and soil degradation. Today, there is limited information about the soil physical and chemical properties in the locality. In this work, we describe the main essential factors or mechanism that control the evolution of the soil in the study area. The physical and chemical properties of soils encountered along a NE-SW transect in are analyzed in this paper. The statistical analysis results revealed low structural stability of soils in general, due to their low organic matter content and exchangeable bases and their predominantly silty texture. A net trend towards acidification, which is more pronounced in the lower-bottom and terrace soils, provides information on the conditions that are increasingly unfavorable to agricultural development. The multivariate principal component analysis (PCA) identified the preponderance of two factors among the four primarily involved in soil geochemical composition. These include a mineralization process (expressed through the first principal component (PC1), which causes soils to be rich in elements (Ca2+, K+,C, N, MO) controlling their structure and fertility level;  The PC2 axis expresses the spatial differentiation phenomenon of the soil granulometric composition: soils forming cluster poles according to their textural affinity in the projection of the plane formed by these two components , with on one side the sandy-dominated soils of the shallows and terraces and on the other the clay-dominated soils of the plateau and the slope. A clear reversal of textural polarity in the studied topo sequence that must be blamed on the strong water erosion in this area.


2018 ◽  
Vol 25 (1) ◽  
Author(s):  
Sandra Santana de Lima ◽  
Marcos Gervasio Pereira ◽  
Gilsonley Lopes dos Santos ◽  
Rafael de Moura Pontes ◽  
Anderson Ribeiro Diniz

2015 ◽  
Vol 46 (6) ◽  
pp. 954-968
Author(s):  
M. Gromadzka ◽  
A. Wolanin ◽  
M. Żelazny ◽  
Ł. Pęksa

This paper describes research on two of the largest karst springs in Poland's Tatra Mountains – Goryczkowe and Bystrej Górne – both located in the Tatra National Park. The aim of the study was to determine the potential contributing area for the Bystrej Gorne Spring. Research has shown that seasonal changes in the physical and chemical properties of water in both springs followed a similar pattern; however, observed differences were not statistically significant. Additionally, research has shown that the potential contributing area is different than that previously identified by other researchers. The chemical composition of water obtained from each spring was dominated by Ca2+ and HCO−3, and included small amounts of the biogenic NO−3 ion. The highest values of the measured physical and chemical parameters were noted in winter, while the lowest values were noted in spring and summer. Principal component analysis was used to assess the physical and chemical parameters of water obtained from both studied springs. Water dilution and catchment biological activity were identified as two key processes affecting physical and chemical properties of karst spring water. Several differences were identified between the springs – water temperature, pH, mineralization, as well as the concentration of Mg2+, HCO−3, and SO24.


2013 ◽  
Vol 1 (02) ◽  
pp. 40-45
Author(s):  
Felix Ogbemudia ◽  
Emem Mbong

The physical and chemical properties of soils and plants distribution in metropolitan dumpsites in Uyo, Nigeria were studied. Soil samples were collected from two popular dumpsites and analysed using standard scientific procedures. The Results showed that there were slight desparities in the nutrient profile of these dumpsites. Generally, the nutrients levels were high and soil heavy metals concentration were found to be within permissible limits. This study also revealed the monospecific nature of dumpsite 1 and higher species presence corresponding with increased nutrient levels in dumpsite site 2. This study encourages the use of dumpsites soils for agricultural purpose(s) when the soil heavy metal falls within permissible range.


2020 ◽  
Vol 51 (5) ◽  
pp. 1290-1299
Author(s):  
Qadir & Azeez

This study was conducted to assess desertification for dry lands in some parts of Iraq. The study area located between longitudes 43025- 41" - 460 28- 01" E and latitudes 340 18- 35" - 360 20- 56" N with an area of 26500Km2which include some parts of the governorates of Sulaimani, Diyala, Kirkuk, and Erbil in Iraq.  Eighty nine surface soil samples were taken, air dried, sieved through a 2 mm sieve and then analyzed for some physical and chemical properties.   Desertification is assessed according to Mediterranean Desertification and Land Use model (MEDALUS). ArcGIS 10.2 was used to analyze and prepare the layers of soil quality maps. In turn the geometric mean of all six quality maps was used to generate a single desertification status map .In calculating the weight of the soil quality indicator SQI it seems that it was divided into two classes, firstly, class 2(moderate quality) with an area of 25147 km2, which occupied 95% of the study area and the rest is class3 (low quality) with an area of ​​1309 km 2 which equal to 5% of the total area.


2019 ◽  
Vol 44 (2) ◽  
pp. 146
Author(s):  
Jamilah Munir ◽  
Welly Herman

          The objective was to examine the phenomenon of physical and chemical properties of soil which is used as a center of agricultural cultivation in supporting food security in West Sumatra. The experiment was conducted by survey to various locations by taking composite soil samples in the field. Some types of soil taken include Histosol from Anai Padang Pariaman; Ultsiol from Lubuk Minturun; Inceptisol from Limau Manis and Siteba city of Padang; Andisol from Danau Kembar and Lembah gumanti Kab. Solok.  The result was can be concluded that Ultisol Lubuk Minturun more potency for  tropical fruits. Andisol in Lembah Gumanti and Danau Kembar Kab. Solok has decreased its chemical quality. It is necessary to increase soil pH to be suitable for the development of vegetable crops and food crops. The use of lime and organic matter in a proper fertilizing package can reduce the use of heavy fertilizer for vegetable crops and horticultura. Histosol utilization for wetland rice cultivation needs to be careful because the acidic pH and the number of organic acids are toxic. Inceptisol Limau Manis Padang has a neutral pH, and is very good for developing food cultivation in support of food security in West Sumatra.


2018 ◽  
Vol 10 (1) ◽  
pp. 797-806
Author(s):  
Hongyi Zhou ◽  
Huixia Li

Abstract Collapsed walls cause collapsed mounds, and the disintegration characteristics of collapsed walls are thus closely linked with the occurrence of collapsed mounds. The current study examines the disintegration characteristics and the physical and chemical properties of collapsed walls. A multilevel analysis was conducted by obtaining soil samples from four layers of a collapsed wall. The results showed that 1) the physical and chemical properties of the soil samples (red soil layer, sandy soil layer, debris layer, gravel and eluvial breccia) are closely related to the weathering degree of the crust; 2) gravel and eluvial breccia disintegrated in the shortest time, whereas red soil exhibited the slowest disintegration in the vertical section of the collapsed wall. The order of the disintegrating ratio of the layers is as follows: red soil layer < sandy soil layer < debris layer < gravel and eluvial breccia. Initial water content significantly influenced the disintegration ratio of the red soil layer and sandy soil layer, whereas its effect on the debris layer and gravel eluvial breccia is minimal; and 3) most of the physical and chemical properties of the collapsed wall are significantly correlated with the disintegration ratio of the soil sample. The following physical and chemical properties, which are positively correlated with the disintegration ratio, are arranged based on highest to lowest correlation coefficient: sand content, MgO, natural water content, K2O, CaO, exchangeable sodium, pH, porosity, Na2O, and cation exchange capacity. The following physical and chemical properties, which are negatively correlated with the disintegration ratio, are organized based on highest to lowest correlation coefficient: cosmid, Fe2O3, silt particle, Al2O3, TiO2, SiO2, organic matter, free iron oxide, and free alumina. Only exchangeable calcium, saturated water content, specific gravity of soil particles, and dry density of soil particles are significantly correlated with the disintegration ratio. The correlation coefficient indicates that the disintegration ratio and soil structure, as well as the chemical content of clay minerals, are closely correlated. The study helps explain the mechanism of wall collapse and provides references for developing protective measures against erosion.


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