Biological Properties of Forest Soils

Forest Soils ◽  
2013 ◽  
pp. 77-95
Author(s):  
Khan Towhid Osman
Keyword(s):  
Forest Soils ◽  
Biological Properties

IMPACT OF WINDTHROWS DISTURBANCE ON CHEMICAL AND BIOLOGICAL PROPERTIES OF THE FOREST SOILS FROM ROMANIA

2021 ◽  
Vol 20 (7) ◽  
pp. 1163-1172
Author(s):  
Aurelia Onet ◽  
Vlad Emil Crisan ◽  
Lucian Constantin Dinca ◽  
Cosmin Ion Braga ◽  
Raluca Elena Enescu ◽  
...  
Keyword(s):  
Forest Soils ◽  
Biological Properties

scholarly journals Impact of water erosion on the properties of forest soils

2021 ◽  
Vol 13 (2) ◽  
pp. 10921
Author(s):  
Ayoub ALLAM ◽  
Amine H. BORSALI ◽  
Abdelkrim KEFIFA ◽  
Mohamed ZOUIDI ◽  
Anne M. FARNET DA SILVA ◽  
...  
Keyword(s):  
Forest Soils ◽  
Research Work ◽  
Chemical Properties ◽  
Water Erosion ◽  
Negative Influence ◽  
Biological Properties ◽  
Basal Respiration ◽  
Control Zone ◽  
Physicochemical And Biological Properties ◽  
And Control

The research work was conducted on eroded soil in the Keroua forest of Saida, Algeria, whose objective is to know the changes in the physicochemical and biological properties of forest soils subjected to the effect of water erosion. The samples were taken to a depth between 0-10 cm in each zone (eroded zone and control zone). Our results show that the biological properties are the most affected by water erosion where there was a significant decrease in basal respiration and microbial biomass, which had a negative influence on the metabolic quotient (higher values in the eroded area). For chemical properties, there was an increase in organic matter and total limestone, while the pHWater decreased in the eroded zone. For the physical properties. We raised a slight difference between the two areas, but which was not statistically significant.

scholarly journals Effect of Fires on Certain Properties of Forest Soils in Western Algeria

2020 ◽  
Vol 23 (3) ◽  
pp. 111-117
Author(s):  
Ayoub Allam ◽  
Amine Habib Borsali ◽  
Abdelkrim Kefifa ◽  
Mohamed Zouidi ◽  
Raphael Gros
Keyword(s):  
Forest Soils ◽  
Forest Fires ◽  
Arid Zone ◽  
Chemical Properties ◽  
Biological Properties ◽  
Basal Respiration ◽  
Arid Ecosystems ◽  
Control Zone ◽  
The Impact ◽  
Semi Arid

AbstractNatural disturbances, such as forest fires, cause significant changes in the structure and functioning of semi-arid ecosystems. After such disturbances, the impact on the soil ecosystem in its entirety is misunderstood. In this study, two years after the last fire, changes in the physicochemical and biological properties of Aleppo pine forest soils in the semi-arid zone were observed. Among all physical properties analysed, only the soil moisture remained significantly lower in the burnt zone in contrast to control zone. Considering the chemical properties, the only negatively affected parameter is the rate of organic matter. In terms of biological properties, results showed that the fire caused a significant decrease in soil microorganisms by decreasing basal respiration and microbial biomass. Conversely, the metabolic quotient recorded higher values in the fire zone than in the control zone. These results indicate that microbial communities in semi-arid soils, already stressed by climatic hazards, are very sensitive to the passage of even low-intensity fires.

INFLUENCE OF SILVER POLLUTION ON THE ACTIVITY OF SOIL CATALASE IN SOUTH OF RUSSIA

2020 ◽  
Vol 6(72) (2) ◽  
pp. 259-266
Author(s):  
N. I. Tsepina ◽  
L. V. Sudina ◽  
T. V., Minnikova ◽  
S. I. Kolesnikov
Keyword(s):  
Biological Activity ◽  
Forest Soils ◽  
Catalase Activity ◽  
Biological Properties ◽  
Ecological Condition ◽  
Ordinary Chernozem ◽  
Chemical Pollution ◽  
Mineralization Processes ◽  
Regions Of Russia ◽  
Brown Forest Soils

Due to the widespread use of products based on silver nanoparticles, the risk of contamination of the soil cover and surface water increases, since an element in this form can leach out of the material. The amount of silver emissions into the environment is increasing every year. There is growing evidence of silver toxicity for living organisms of not only aquatic, but also terrestrial ecosystems. Silver, accumulating in soil in large quantities, like other heavy metals, can have a toxic effect on the physical, chemical and biological properties of the soil.High doses of the element can have a significant effect on the biological properties and ecological condition of soils. The study of enzyme activity can be used to identify major changes in the soil under the influence of silver. In this regard, it is relevant to study the effect of silver on catalase activity, since this enzyme is an indicator of the potential biological activity of the soil and reflects the intensity of mineralization processes in it. The aim of the work was to study the effect of silver pollution on the activity of soil catalase most characteristic of the southern regions of Russia. The object of the study identified soils characteristic of southern Russia: ordinary chernozems, seropesks and brown forest soils. For model studies, soil samples were taken from the upper arable layer (0‑10 cm), since silver accumulates in the surface soil layers. Silver pollution was modeled in a laboratory. Used silver nitrate at a concentration of 1 mg / kg, 10 mg / kg and 100 mg / kg, the experiment was 3 times biological repetition. The choice of biological indicators is due to the fact that oxidoreductases are most sensitive to chemical pollution among enzymes. This enzyme is an indicator of the biological activity of the soil and reflects the intensity of the mineralization processes in it. Laboratory and analytical studies were carried out using generally accepted methods in biology, soil science and ecology. Catalase activity was determined by the volumetric method according to A.Sh. Galstyan. As a result of the study of the effect of silver on three types of soils, the most characteristic of the southern regions of Russia, a decrease in catalase activity was noted. The degree of reduction of this indicator depended on the dose of the element introduced into the soil. The degree of resistance to silver contamination has the following sequence: common chernozem> sulfur sands ≥ brown forest soil. This is probably due to the light particle size distribution of sulfur sand and the acidic reaction of the environment of brown forest soils (pH = 5.8), as well as a low content of organic matter (1.8 % and 2.3 %, respectively), which contributes to high mobility, and therefore and high ecotoxicity of silver in these soils. A decrease in the activity of catalase of ordinary chernozem was observed for 90 days. At 1 UDC on the 30th and 90th day of the experiment, the same decrease in the studied parameter was observed. A similar pattern was observed at 10 UDC at the same experimental time. At 100 UDC (100 mg / kg) on the 90th day after contamination, a tendency toward restoration of catalase activity was observed, however, control values before silver contamination were not achieved. Chernozems have a high number of microorganisms and their high activity, and pollution tolerance mechanisms provide detoxification of soils from exposure to silver.

scholarly journals Silver Ecotoxicity Estimation by the Soil State Biological Indicators

2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
S. I. Kolesnikov ◽  
N. I. Tsepina ◽  
L.V. Sudina ◽  
T. V. Minnikova ◽  
K. Sh. Kazeev ◽  
...  
Keyword(s):  
Forest Soils ◽  
High Mobility ◽  
Biological Indicators ◽  
Biological Properties ◽  
Silver Concentration ◽  
Ordinary Chernozem ◽  
Environmental Consequences ◽  
Haplic Chernozems ◽  
Activity Of Enzymes ◽  
Brown Forest Soils

The use of silver in various spheres of life and production leads to an increase in environmental pollution, including soil. At the same time, the environmental consequences of silver pollution of soils have been studied to a much lesser extent than those of other heavy metals. The aim of this study is to estimate silver ecotoxicity using the soil state biological indicators. We studied soils that are significantly different in resistance to heavy metal pollution: ordinary chernozem (Haplic Chernozems, Loamic), sierosands (Haplic Arenosols, Eutric), and brown forest acidic soil (Haplic Cambisols, Eutric). Contamination was simulated in the laboratory. Silver was introduced into the soil in the form of nitrate in doses of 1, 10, and 100 mg/kg. Changes in biological parameters were assessed 10, 30, and 90 days after contamination. Silver pollution of soils in most cases leads to deterioration of their biological properties: the total number of bacteria, the abundance of bacteria of the genus Azotobacter, the activity of enzymes (catalase and dehydrogenases), and the phytotoxicity indicators decrease. The degree of reduction in biological properties depends on the silver concentration in the soil and the period from the contamination moment. In most cases, there is a direct relationship between the silver concentration and the degree of deterioration of the studied soil properties. The silver toxic effect was most pronounced on the 30th day after contamination. In terms of their resistance to silver pollution, the studied soils are in the following order: ordinary chernozem > sierosands ≥ brown forest soil. The light granulometric composition of sierosands and the acidic reaction of the environment of brown forest soils, as well as the low content of organic matter, contribute to high mobility and, consequently, high ecotoxicity of silver in these soils. The regional maximum permissible concentration (rMPC) of silver in ordinary chernozem (Haplic Chernozems, Loamic) is 4.4 mg/kg, in sierosands (Haplic Arenosols, Eutric) 0.9 mg/kg, and in brown forest soils (Haplic Cambisols, Eutric) 0.8 mg/kg.

Three Dimensional structure and organization of diploid chromosomes by optical section microscopy

1987 ◽  
Vol 45 ◽  
pp. 633-635
Author(s):  
David A. Agard ◽  
Yasushi Hiraoka ◽  
John W. Sedat
Keyword(s):  
Dimensional Space ◽  
Three Dimensional ◽  
Developmental State ◽  
Mitotic Cell ◽  
Biological Properties ◽  
Dimensional Structure ◽  
Specific Gene ◽  
Three Dimensional Structure ◽  
Complementary Techniques ◽  
Dynamic Structures

In an effort to understand the complex relationship between structure and biological function within the nucleus, we have embarked on a program to examine the three-dimensional structure and organization of Drosophila melanogaster embryonic chromosomes. Our overall goal is to determine how DNA and proteins are organized into complex and highly dynamic structures (chromosomes) and how these chromosomes are arranged in three dimensional space within the cell nucleus. Futher, we hope to be able to correlate structual data with such fundamental biological properties as stage in the mitotic cell cycle, developmental state and transcription at specific gene loci.Towards this end, we have been developing methodologies for the three-dimensional analysis of non-crystalline biological specimens using optical and electron microscopy. We feel that the combination of these two complementary techniques allows an unprecedented look at the structural organization of cellular components ranging in size from 100A to 100 microns.

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