The concept of soil from different perspectives
In the field of soil science, it is still rare to summarize soil concepts from the perspective of plant physiology. The soil concept proposed by EAMitscher-lich (1950) is an example. He thinks: “For plant physiologists, the soil is surface powdery a mixture of solid particles, water and air, and growing plants under the influence of climate influences."
The concept of soil considers: “When we talk about soil, what we understand is the loose surface layer on the earth's land that can produce plant harvests.†This soil concept is based on the ability to produce plant harvests as a soil marker. The important characteristics of sex. Since the soil-derived plant harvest is a product of economic value, not any product of blindness in social production, the soil concept proposed by Williams is based on whether it can produce agricultural economic products as a criterion, that is, Summarize the soil from the perspective of economics. The soil concept proposed by BPB and Jlboc was used by some soil sciences in China in the 1950s and early 1960s, such as those compiled by Huang Ruicai (1958), Beijing Forestry College (1962) and Shenyang Agricultural College (1962). Soil science or agricultural pedology used this concept. The concept of soils belonging to this category in soil science in Europe and the United States is also rare.
To summarize the typical example of soil from an ecological point of view, as indicated by the concept of soil proposed by H. Lundegardh (1954), that is to say: “From an ecological point of view, we call the portion of the crust where plants are grown as a slope.†R.Don 5 ae (1977) put it more clearly: “The soil in traditional concepts is the natural medium for the growth of terrestrial plants, regardless of whether or not there is a recognizable layer of soil A.†This is very It is clearly negated that the concept of soil that can only be counted as soil from the viewpoint of soil genetics, must have “own structure and a certain level of certaintyâ€, as the soil concept proposed by I. Lieberoth (1964). In addition, the concept of soil proposed by C. Arles D. Sopher, et al. (1978) recently concluded that “a soil is an aggregate of surface natural objects that have a living material and that supply or can supply plants.†This is from the soil and the plant. The relationship is summed up, this ecological relationship is explained by the soil can supply plant life material.
The soil sciences edited by many colleges such as Shenyang Agricultural College and Beijing Forestry College all describe the fact that Xu Shen had made a clear summary of the soil in the ancient book Shuo Wen Jie Zi in the Eastern Han Dynasty. , that is, the idea of ​​giving birth to all things. The soil, let also, that is, soft soil without block and should cultivate the soil." From the perspective of modern soil science, Xu Shen's interpretation of the concept of Tucheng, basically starting from the ecological To illustrate the soil. This is the earliest written record of the concept of soil so far.
E. Ehwald (1960) strongly emphasized the exchange of material between soil and vegetation, stating that: “Loose sediments that have been free of vegetation are not soils because they lack the largest part of the material exchange process characteristic of soil, but E. Ehwald (1960) did not attempt to generalize the concept of soil.
Related Soil Instruments: Soil Nutrient Tester Soil Moisture Meter
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