How Crops Feed. A Treatise on the Atmosphere and the Soil as Related to the Nutrition of Agricultural PlantsO. Judd Company, 1870 - 375 páginas |
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Términos y frases comunes
absorbed absorption acre action adhesion agricultural alkali alumina ammonia amount amphibole analysis apocrenic atmosphere bodies Boussingault carbonate of lime carbonic acid cent charcoal chemical chloride clay color combination composition compounds condensed crops cubic decay decomposed decomposition dilute dissolved earth exhaled exist experiments fact feldspar fertility foliage formed free nitrogen gases glass grains grams grms heat hippuric acid humates humic acid humus hydrated hydrogen hygroscopic inches ingredients insoluble kaolinite Knop lime liquid magnesia manured mineral mixture moist moisture Mulder nearly nitrate of potash nitric acid nitrogen nitrous organic matters oxide oxide of iron oxygen ozone particles peat phosphate phosphoric acid plants porous portion potash proportion protoxide pure quantity quartz rain rocks roots salts sand sandy saturated Saussure seeds sesquioxide silicates soda soil soil contained soluble solution substances sulphate sulphuric acid supply surface temperature tion urine vapor vegetation vessel weight yield zeolites
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Página 180 - Obviously, too, the quantity of liquid in a given volume of soil affects not only the rapidity, but also the duration of evaporation. The following table, by Schubler, illustrates the peculiarities of different soils in these respects. The first column gives the percentages of water absorbed by the completely dry soil. In these experiments the soils were thoroughly wet with water, the excess allowed to drip off, and the increase of weight determined. In the second column are given the percentages...
Página 190 - ... by strewing a coating of coal-dust an inch deep over the surface of the soil. In some of the vineyards of the Rhine, the powder of a black slate is employed to hasten the ripening of the grape. Girardin, an eminent French agriculturist in a series of experiments on the cultivation of potatoes found that the time of their ripening varied eight to fourteen days, according to the character of the soil. He found, on the 25th of August, in a very dark soil made so by the presence of much humus or...
Página 157 - ... impenetrable, crust or stratum of ochrey clay or compacted gravel, often underlying a fairly fruitful soil. It is the soil reverting to rock, the particles being cemented together again by the solutions of lime, iron, or alkali-silicates and humates that descend from the surface soil. Peat swamps thus exist in basins formed on the most porous soils by a thin layer of moorbed-pan.89 Detmer and others have given similar descriptions.
Página 216 - Whitney2 claims that the moisture supply in the soil .is the only important factor to be regulated by the cultivator in most soils, all other factors being, in general, provided for naturally. 'A generation ago Johnson3 wrote : " It is a well recognized fact that next to temperature, the water supply is the most influential factor in the product of a crop.
Página 178 - ... with sunshine and wind, the surface of the soil rapidly dries ; but as each particle of water escapes (by evaporation) into the atmosphere, its place is supplied (by capillarity) from the stores below. The ascending water brings along with it the soluble matters of the soil, and thus the roots of plants are situated in a stream of their appropriate food.
Página 141 - We frequently find in meadows smooth limestones with their surfaces ' covered with a network of small furrows. When these stones are newly taken out of the ground, we find that each furrow corresponds to a rootlet, which appears as if it had eaten its way into the...
Página 177 - ... body will suck up and hold water—will exhibit capillarity; a lump of salt or sugar, a lamp-wick, are familiar examples. When the pores of a body are so large (the surfaces so distant) that they cannot fill themselves or keep themselves full, the body allows the water to run through or to percolate. When a soil is too coarsely porous it is said to be leachy or hungry. The rains that fall upon it quickly soak through, and it shortly becomes dry. On such a soil, the manures that may be applied...
Página 180 - ... In these experiments the soils were thoroughly wet with water, the excess allowed to drip off, and the increase of weight determined. In the second column are given the percentages of water that evaporated during the space of four hours from the saturated soil spread over a given surface." TABLE V. "It is obvious that these two columns express nearly the same thing in different ways. The amount of water retained increases from quartz sand to magnesia. The rapidity of drying in the air diminishes...