1. Soil is a base for plant growth and biological production Soil is a base for plant production. Sunlight (light energy), heat (heat energy), air (oxygen and carbon dioxide), water and nutrients are the five basic elements for the growth and development of green plants, in which nutrients and moisture are obtained from the soil through the root system. Plants can be based on the natural world, can withstand wind and rain without lodging, because their roots stretch in the soil and obtain the mechanical support of the soil. The data obtained by scientists using soil instruments such as soil nutrient testers for soil sample research and testing indicates that in nature, plant growth must be based on soil. Lang's soil can provide plants with sufficient supply of water and nutrients, with appropriate temperature and ventilation conditions, suitable for full extension of the root system, and strong mechanical anchorage. To sum up, the soil has the following effects in plant growth: Learn more about technical parameters and price quotes for soil testing instruments such as soil testing instruments.
Description:
AWS E7018 Welding Electrodes is a iron powder low hydrogen type Carbon Steel Welding Electrodes.It can be used for all postion welding,small spatters, easy restrike arc, high welding efficiency, fine appearance and slag easy to remove.
Application:
Suitable for welding important medium carbon steel and low alloy steel, such as 16Mn steel, parts of ships fabricated by A,B,D,E grade steel as well as parts of boilers presssure vessels and pipes.
Attention:
a. Welding electrodes should be backed at the temperature of 350℃ for one hour before welding, and then use them when baking.
b. Before welding, the weld metal must be cleared away impurities, such as rust oil, moisture, etc.
c. Short arc and narrow weld bead are recommended in welding.
Packing:
2.5mm*300mm 2.5kgs/inner box, 8inner boxes/carton=20kgs
3.2mm*350mm 5.0kgs/inner box, 4inner boxes/carton=20kgs
4.0mm*400mm 5.0kgs/inner box, 4inner boxes/carton=20kgs
5.0mm*400mm 5.0kgs/inner box, 4inner boxes/carton=20kgs
Aws E7018 Welding Electrodes,E7018 Welding Electrode,7018 Welding Rod,E7018 Welding Rod Dingzhou Jinlong Metal Production Co., Ltd. , http://www.weldingelectrodefactory.com
(1) Role of nutrient stores In addition to carbon dioxide, which is mainly derived from air, the nutrients needed by plants, such as nitrogen, phosphorus, potassium, and medium and micronutrients, and water, come mainly from the soil. Although the area of ​​the ocean accounts for two-thirds of the Earth's surface area, the total amount of chlorine and phosphorus stored in terrestrial soil and biological systems is much higher than that in aquatic organisms and water bodies. Soil is an important source of nutrients essential for terrestrial organisms. .
(2) Nutrient Transformation and Circulation The transformation of nutrient elements includes both the organicization of inorganic materials and the mineralization of organic materials, both the release and loss of nutrients, and the combination, fixation, and return of elements. Through the complicated transformation process of the soil nutrient yuan family, the circulation and turnover between nutrient elements and organisms are realized in the Earth's surface system, and the life cycle and reproduction of the biological life cycle are maintained.
(3) Rainwater Conservation Soil is a medium with biological activity and various structures on the Earth's land surface. It has strong water absorption and water holding capacity. According to the data of the soil moisture analyzer, it can be found that the soil's rainwater conservation function is closely related to the soil's total porosity, organic matter content and other soil physical and chemical properties and vegetation coverage. The interception of rainwater by the foliage of plants and the retardation of surface runoff, as well as the impact of root penetration and humus layer formation on the infiltration, can greatly enhance the ability of the soil to maintain rainwater.
(4) Supporting function Plants grow in the soil, and the root system spreads and intersperses in the soil to obtain the nutrients and mechanical support of the soil, so that the above-ground part of the plant stands stably in nature. In the soil, there are also a large variety and large number of biota, and their survival depends on the soil.
(5) Stabilizing and buffering the role of environmental change Soil is the reaction interface of various physical, chemical, and biochemical processes on the Earth's surface. It is the most complex and frequent zone for the exchange of matter and energy, migration, etc., which makes the soil resistant to the outside world. The buffering capacity of changes in temperature, humidity, acidity and alkalinity, and redox properties, can act as "filters" and "purifiers" for pollutants entering the soil that can be metabolized, degraded, converted, eliminated, or reduced in toxicity through soil organisms. The role of the plant and microorganisms can provide a relatively stable growth and reproduction environment.
2. Soil is an important part of terrestrial ecosystems Ecosystems are the general term for aggregates of plants, animals, and microorganisms and their living environment. Any combination of biomes and the environment in which they are located forms a certain type of ecosystem. The ecosystems of nature vary in size and diversity. Terrestrial ecosystems are "big systems" that cover the entire surface of the earth.
Soil is an important part of terrestrial ecosystems and a relatively independent ecosystem. In the soil ecosystem, the material and energy flow are continuously input from the external environment to the soil. Through migration in the soil, it will inevitably cause changes in the composition, structure, properties, and functions of the soil, thereby promoting the development and evolution of the soil. The output of materials and energy from the soil to the environment will inevitably lead to changes in the composition, structure, and nature of the environment, thus promoting the continuous development and change of the environment.
Green plants are the main organic producers in soil ecosystems, and herbivores or carnivorous animals are the main consumers of soil ecosystems. They use existing organic materials as raw materials, and they are mechanically broken down and biotransformed, with the exception of a small part of the consumption. Most of the substances and energy are still present in the organic state in the soil, animals and their residues and excretions. The organic matter decomposers in soil ecosystems are mainly soil microorganisms and lower animals. Microorganisms include bacteria, fungi, and actinomycetes. Low-level animals include flagellates and ciliates. They use green plants and animal-derived organisms and excrement as raw materials to extract nutrients and energy from them and decompose them into organic compounds. For plant re-use, or synthesis of soil humus that is closely related to soil fertility.
The soil microsystem is an open system with energy flow as the main line, and plays an extremely important role in the terrestrial ecosystem. In addition, the soil ecosystem is not only a natural ecosystem but also an artificial ecosystem dominated by human intelligence and labor, or a composite ecosystem.
The function of the soil ecosystem and the function of the soil are the same. If people want to obtain biological products from the soil, they should return or replenish the soil and remove them from it. Otherwise, they will exploit the soil and will eventually be punished.
The status and role of soil in plant production and ecosystem