The soils of Aldabra

1979 ◽  
Vol 286 (1011) ◽  
pp. 67-77 ◽  
Keyword(s):  
High Salinity ◽  
Mineral Soil ◽  
Soil Types ◽  
Organic Soils ◽  
Patchy Distribution ◽  
Soil Covers ◽  
Terrestrial Sediments ◽  
Soil Information ◽  
Carbonate Soil ◽  
Mineral Soils

The soils of Aldabra are of patchy distribution, consisting of pockets of either accumulated organic matter or of biogenic mineral detritus. The soils are shallow (10-20 cm) but locally deeper and more extensive soil covers do occur. Organic covers occur under well established Casuarina stands and mineral soil covers occur on the floors of rock basins or where sands are present. The organic soils originate from leaf litter, with local increments of faecal material and bird remains. The mineral soils are primarily carbonate and are derived mechanically from carbonate rocks, from windblown bioclastic carbonate grains or from terrestrial sediments. Solution residues and phosphatic particles also contribute to these soils. Attempts are made to cross-correlate existing soil information, and several organic and carbonate soil types can be recognized. These are: shallow organic (including litter, pellet and guano varieties); deep organic; calcarenaceous bioclastic soils; brown (silt or silt loam) carbonate soils (including a phosphatic variety) and a widespread organic brown carbonate soil. The soils may be slightly acid but are mostly circumneutral or alkaline; high salinity may occur in coastal locations. Phosphate levels are usually low. Insufficient profile data are available at present to define soil type in any rigorous way and the spatial distribution of soil types is only scantily known.

scholarly journals Organic Matter Causes Chemical Pollutant Dissipation Along With Adsorption and Microbial Degradation

2021 ◽  
Vol 9 ◽  
Author(s):  
A. Vilhelmiina Harju ◽  
Ilkka Närhi ◽  
Marja Mattsson ◽  
Kaisa Kerminen ◽  
Merja H. Kontro
Keyword(s):  
Organic Matter ◽  
Microbial Degradation ◽  
Mineral Soil ◽  
Organic Soil ◽  
Organic Soils ◽  
First Response ◽  
Chemical Pollutant ◽  
Mineral Soils ◽  
Soil And Sediment

Views on the entry of organic pollutants into the organic matter (OM) decaying process are divergent, and in part poorly understood. To clarify these interactions, pesticide dissipation was monitored in organic and mineral soils not adapted to contaminants for 241 days; in groundwater sediment slurries adapted to pesticides for 399 days; and in their sterilized counterparts with and without peat (5%) or compost-peat-sand (CPS, 15%) mixture addition. The results showed that simazine, atrazine and terbuthylazine (not sediment slurries) were chemically dissipated in the organic soil, and peat or CPS-amended soils and sediment slurries, but not in the mineral soil or sediment slurries. Hexazinone was chemically dissipated best in the peat amended mineral soil and sediment slurries. In contrast, dichlobenil chemically dissipated in the mineral soil and sediment slurries. The dissipation product 2,6-dichlorobenzamide (BAM) concentrations were lowest in the mineral soil, while dissipation was generally poor regardless of plant-derived OM, only algal agar enhanced its chemical dissipation. Based on sterilized counterparts, only terbutryn appeared to be microbially degraded in the organic soil, i.e., chemical dissipation of pesticides would appear to be utmost important, and could be the first response in the natural cleansing capacity of the environment, during which microbial degradation evolves. Consistent with compound-specific dissipation in the mineral or organic environments, long-term concentrations of pentachloroaniline and hexachlorobenzene were lowest in the mineral-rich soils, while concentrations of dichlorodiphenyltrichloroethane (DTT) and metabolites were lowest in the organic soils of old market gardens. OM amendments changed pesticide dissipation in the mineral soil towards that observed in the organic soil; that is OM accelerated, slowed down or stopped dissipation.

scholarly journals Príspevok k problematike určovania špecifickej hmotnosti subhorizontov opadu lesných pôd

2013 ◽  
Vol 59 (1) ◽  
pp. 38-43
Author(s):  
Jana Bútorová
Keyword(s):  
Mineral Soil ◽  
Soil Aggregate ◽  
Soil Samples ◽  
Organic Soils ◽  
Laboratory Methods ◽  
Elementary Unit ◽  
Final Density ◽  
International Laboratory ◽  
Mineral Soils

Abstract According to national and international laboratory methods, the density of soil samples is determined by pycnometer in heated samples crushed by ultrasound. In mineral soils, the elementary unit of density is represented by a mineral grain of quartz, granite, andesite, etc. On the other hand, in organic soils, the elementary unit is represented by a leaf (or just a part of it), needles, stems and roots. Heating of the mineral grain causes its release from the soil aggregate. Organic parts of the soil are losing air vacuoles by heat treatment while in the same time, carbohydrates, proteins, oils and resins create new chemicals which are heavier than water. That is a reason why density determination of litter subhorizons in forest soils needs to have different rules in comparison with mineral soil samples. Samples with more than 50 volume per cent of organic matter are not treated by heat and do not decompose. In case of high mineral soil content, mineral parts are removed from the sample and their density is determined. The final density is based on mathematically processed data.

OXYGEN FLUX MEASUREMENTS IN ORGANIC SOIL

1980 ◽  
Vol 60 (4) ◽  
pp. 641-650 ◽  
Author(s):  
JAMES A. CAMPBELL
Keyword(s):  
Applied Voltage ◽  
Mineral Soil ◽  
Organic Soil ◽  
Oxygen Flux ◽  
Organic Soils ◽  
Wide Range ◽  
Effective Voltage ◽  
Flux Measurements ◽  
Mineral Soils ◽  
Almost All

Many measurements of oxygen flux in mineral soils have been reported; however, few such measurements have been made in organic soil. Almost all reported measurements of oxygen flux are at constant applied voltage, despite criticism of this technique, possibly due to the complexity of existing techniques for measuring oxygen flux at effective voltage. Equipment suitable for measuring oxygen flux at applied and effective voltage in organic soil was designed, and simplified techniques were developed and tested. As reported for mineral soils, soil resistance is relatively constant spatially and with depth in individual soils. Limited poisoning of the platinum electrode surface occurred after long periods of time and, contrary to previous assumptions, cannot be detected by erratic readings. Unlike mineral soil, the amperage-voltage slopes are constant over a wide range of organic soils, simplifying the technique for estimating oxygen flux at constant effective volatage. Comparison of simultaneous measurements of oxygen flux at constant and effective voltage indicates that oxygen flux measurements at effective voltage were twice those at applied voltage and strongly correlated (r2 = 0.96, n = 22).

COBALT STATUS IN QUEBEC SOILS

1967 ◽  
Vol 47 (2) ◽  
pp. 83-88 ◽  
Author(s):  
S. K. Rana ◽  
G. J. Ouellette
Keyword(s):  
Mineral Soil ◽  
Organic Matter Content ◽  
Clay Content ◽  
Cobalt Content ◽  
Matter Content ◽  
Organic Soils ◽  
Soil Series ◽  
Acid Digestion ◽  
Cobalt Deficiency ◽  
Mineral Soils

Studies on thirty mineral soil series and five organic soils from the broad cultivated areas of Quebec indicated that total cobalt, extracted with 70% perchloric acid digestion, ranged from 1.1 to 21.6 ppm and 2.5% acetic acid-extractable cobalt from 0.3 to 0.83 ppm. Extractable cobalt in the surface soils was significantly correlated with total cobalt, which in turn was highly dependent on the clay content of the soil. The soil pH or the organic matter content did not seem to have any influence on the cobalt content in the cultivated soils. Light-textured and podzolized soils are likely to be low m cobalt, while soils with richer clay content are higher. Organic soils, in general, were found to be lower in cobalt content than mineral soils. Nineteen out of the thirty mineral soils studied and all the organic soils contained less than 0.25 ppm of extractable cobalt and may be considered as critical or deficient because forage grown on such soils is likely to cause cobalt deficiency in livestock.

scholarly journals The Possibilities of Using Common Buckwheat in Phytoremediation of Mineral and Organic Soils Contaminated with Cd or Pb

Agriculture ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 562
Author(s):  
Jolanta Domańska ◽  
Danuta Leszczyńska ◽  
Aleksandra Badora
Keyword(s):  
Mineral Soil ◽  
Shoot Biomass ◽  
Organic Soils ◽  
Tolerance Index ◽  
Common Buckwheat ◽  
Plant Growth And Development ◽  
Neutral Soil ◽  
Mineral Soils ◽  
Fagopyrum Esculentum Moench ◽  
Cadmium And Lead

The results of this study provided accurate guidance on the possibility of using common buckwheat (Fagopyrum esculentum Moench) in phytoremediation practices for mineral soil or organic soils contaminated with Cd or Pb. Based on a model pot experiment, the tolerance of buckwheat to elevated contents of cadmium and lead in organic and mineral soils was examined. The soils were differentiated into neutral and acidic, and amended with metals at doses of 10 mg Cd kg−1 DM and 100 mg Pb kg−1 DM of soil. The growth, development, biomass, translocation coefficient, and tolerance index (TI) of the tested plants were examined. The use of metals caused a weakening of plant growth and development, as well as intensified chlorotic and necrotic changes to the buckwheat leaves. The application of Cd caused a statistically significant decrease in shoot biomass. The plants growing in organic acidic soil were most vulnerable to Cd toxicity. The (TI) values confirm the generally low tolerance of buckwheat to Cd, except for the treatment in organic neutral soil, and the high tolerance of this plant to Pb in all the studied soils.

scholarly journals Produktivitas Tiga Genotipe Kedelai dengan Air Berbeda dan Kedalaman Muka Air pada Berbagai Kondisi Tanah di Pasang Surut

2017 ◽  
Vol 44 (3) ◽  
pp. 248 ◽  
Author(s):  
Hesti Pujiwati ◽  
Sandra A. Aziz ◽  
Munif Ghulamahdi ◽  
Sudirman Yahya ◽  
Dan Oteng Haridjaja
Keyword(s):  
Water Level ◽  
Mineral Soil ◽  
High Tide ◽  
Soil Types ◽  
Water Composition ◽  
Tidal Swamp ◽  
Growing Environment ◽  
Mineral Soils ◽  
Fe Toxicity ◽  
Plot Design

<em>ABSTRACT<br /><br />Soybean extensification on mineral and peaty mineral soils of tidal land are limited by Al and Fe toxicity.  Modification of growing environment and the use of tolerant variety are the possible alternatives to overcome the limitation.  The research was aimed to study soybean productivity in various soil types with different depth of water level and different water compositions. The experiment was held under mineral, peaty mineral soils with interaction types B and C  of tidal swamp in Banyuasin, South Sumatera from May to August 2014.  At each location, there was a three factor experiment was arranged in a split-split plot design. The first factor was two water depth (10 and 20 cm), the second factor was three varieties (Tanggamus, Cikuray, Ceneng) and third factor was three different water compositions (river water, peat water, high-tide water). The results showed productivity on mineral soil types C, peaty  mineral soil types B, and mineral soil types B were 4:50, 3.65, 0:32 ton ha-1 respectively. In peaty mineral soil types B, Ceneng with a depth of 20 cm water level resulted in highest productivity. In the mineral soil overflow type B, Cikuray with peat water composition had highest productivity.<br /><br />Keywords: mineral, peaty mineral, sensitive, tolerant<br /><br /></em>

scholarly journals A New Approach to the Determination of Mineral and Organic Soil Types Based on Dilatometer Tests (DMT)

2018 ◽  
Vol 8 (11) ◽  
pp. 2249 ◽  
Author(s):  
Simon Rabarijoely
Keyword(s):  
Pore Water Pressure ◽  
Water Pressure ◽  
Organic Soil ◽  
Soil Types ◽  
Organic Soils ◽  
New Classification ◽  
New Approach ◽  
Mineral Soils ◽  
Material Index

In order to identify the soil type in the ground, Marchetti’s nomogram chart is commonly used on the basis of dilatometer tests (DMT). In this chart, the material index values (ID) and the dilatometer modulus (ED) are used to determine the state and type of soils predominant in mineral soils. Unfortunately, this classification is not accurate enough for the identification of organic soils. This article proposes a new classification based on a nomogram chart for both mineral soils and organic soils using (p0), (p1) readings and pore water pressure (uo).

scholarly journals Abundance of the Sugarcane Borer (Lepidoptera: Crambidae) and Foraging Ants (Hymenoptera: Formicidae) in Sugarcane Grown on Organic and Mineral Soils in Florida

2020 ◽  
Vol 49 (2) ◽  
pp. 473-481
Author(s):  
Erik L Roldán ◽  
Julien M Beuzelin ◽  
Matthew T VanWeelden ◽  
Ronald H Cherry
Keyword(s):  
Soil Type ◽  
Solenopsis Invicta ◽  
Mineral Soil ◽  
Organic Soil ◽  
Organic Soils ◽  
Red Imported Fire Ant ◽  
Sugarcane Borer ◽  
Parasitism Rates ◽  
Solenopsis Invicta Buren ◽  
Mineral Soils

Abstract A study was conducted in Florida to determine sugarcane borer, Diatraea saccharalis (F.), injury and infestation levels in sugarcane (Saccharum spp. hybrids), D. saccharalis parasitism rates, and ant foraging activity in 32 commercial fields as affected by soil type (shallow organic vs deep organic vs mineral). In 2017 and 2018, each field was sampled four times during the summer for D. saccharalis by inspecting 100 sugarcane stalks and for foraging ants using plastic tubes baited with hot dog at 12 locations. One non-parasitized D. saccharalis larva was collected in 2017 and in 2018 out of 12,100 and 12,600 stalks sampled, respectively. Additional sampling of 50 stalks per field in October showed that 0.6% (2017) and 0.1% (2018) of the sugarcane stalks had bored internodes, and one Cotesia flavipes (Cameron) (Hymenoptera: Braconidae) cocoon mass was observed. Seven ant species foraged in sugarcane fields, including the red imported fire ant, Solenopsis invicta Buren, which was the most abundant ant. Solenopsis invicta was not affected by soil type; however, sugarcane fields on shallow organic soils might represent a more suitable environment. The third most abundant foraging ant, Nylanderia bourbonica (Forel), was more abundant in mineral soil fields than in shallow and deep organic soil fields. Results suggest that D. saccharalis population levels in Florida sugarcane are extremely low under current production conditions regardless of soil type. In addition, the observation of C. flavipes, S. invicta, and six other ant species suggest that biological control contributes to these low D. saccharalis population levels.

GRANULAR INSECTICIDES AGAINST OVERWINTERED TUBER FLEA BEETLE, EPITRIX TUBERIS GENTNER (COLEOPTERA: CHRYSOMELIDAE), ON POTATO

1991 ◽  
Vol 123 (2) ◽  
pp. 333-343 ◽  
Author(s):  
R.S. Vernon ◽  
J.R. Mackenzie
Keyword(s):  
Pest Management ◽  
Flea Beetle ◽  
Soil Types ◽  
Effective Control ◽  
Organic Soils ◽  
Summer Generation ◽  
Systemic Insecticides ◽  
Flea Beetles ◽  
Mineral Soils ◽  
Fraser Valley

AbstractSix systemic and two nonsystemic granular insecticides were evaluated by application in the furrow at planting for control of overwintered tuber flea beetles, Epitrix tuberis Gentner. Studies were conducted from 1986 to 1988 in three soil types in the lower Fraser Valley of British Columbia. Of the registered systemic insecticides tested, phorate and aldicarb gave rapid and consistent control of overwintered adults released on the foliage 24–30 days after planting, whereas disulfoton and carbofuran were either less effective or more variable in their control. Terbufos and cloethocarb, not registered for use on potatoes, gave control of adult beetles similar to that of phorate and aldicarb. Mortality of overwintered generation adults resulting from these systemic insecticides was correlated with numbers of beetles emerging in the summer adult generation. Neither fonofos nor chlorpyrifos, the nonsystemic granular insecticides, gave effective control of overwintered flea beetles. Only fonofos significantly reduced the emergence of beetles of the summer generation, but the control was inconsistent between years. When beetles were released on the foliage 56 and 65 days after planting, the fewest beetles emerged from the phorate and terbufos plots. All treatments were less effective in highly organic soils than in mineral soils. The advantages of using granular systemic insecticides for controlling overwintered E. tuberis, and strategies for improving control in association with integrated pest management programs are discussed.

scholarly journals Growth, Development and Ornamental Value of Miscanthus sinensis (Andersson) Species Depending on the Dose of Shrimp Biowaste

Agriculture ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 67
Author(s):  
Piotr Żurawik
Keyword(s):  
High Salinity ◽  
Mineral Soil ◽  
Growing Season ◽  
Miscanthus Sinensis ◽  
Alkaline Ph ◽  
Important Group ◽  
Planting Material ◽  
Miscanthus Giganteus ◽  
Before And After ◽  
Marine Products

Crustaceans, including shrimps, are an important group of marine products processed in over 50 countries around the world. It is one of the most profitable and fast-growing processing branches. About 30 to 40% of crustaceans are used immediately after fishing, while 60–70% are processed. This generates thousands of tons of waste, proper management of which becomes increasingly important. The study was conducted in the years 2015–2017. Planting material included rhizomes of Miscanthus sinensis and Miscanthus × giganteus. Shrimp shells, dried and fragmented into 2–3 mm long pieces, were added to the soil at a dose of 5%, 10% and 15%. Mineral soil without the dried waste served as control. pH and substrate salinity were determined both before and after the growing season, and vegetative and generative traits of the plants were assessed. Shrimp biowaste is rich in N, P, K, Ca and Mg, has alkaline pH and high salinity. Its effects on plants depend on its dose and plant species. Miscanthus sinensis turned out more sensitive to the substrate salinity but in both species shrimp biowaste improved their ornamental value. For Miscanthus sinensis the most beneficial dose was 5%, while for Miscanthus × giganteus it was 15%.

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