First Principles of Soil FertilityKegan Paul, Trench, Trubner, 1910 - 265 páginas |
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Página 6
... increased ; for in the latter case the interest on the money invested in one hundred acres of land would be clear gain . On the other hand , it is apparent that nothing is gained by increased production per acre if the larger crop is ob ...
... increased ; for in the latter case the interest on the money invested in one hundred acres of land would be clear gain . On the other hand , it is apparent that nothing is gained by increased production per acre if the larger crop is ob ...
Página 16
... increase in yield can be obtained by irrigation even in sections of very heavy precipitation . While the amount of water that falls on the land can not be controlled , much can be done to save the water so as to tide over the periods of ...
... increase in yield can be obtained by irrigation even in sections of very heavy precipitation . While the amount of water that falls on the land can not be controlled , much can be done to save the water so as to tide over the periods of ...
Página 19
... that the supply of carbon in the air is ample for the largest crops . To be sure , in certain pot experiments a larger yield was obtained by increasing the carbonic acid in the air , ATMOSPHERE AS A SOURCE OF PLANT FOOD 19.
... that the supply of carbon in the air is ample for the largest crops . To be sure , in certain pot experiments a larger yield was obtained by increasing the carbonic acid in the air , ATMOSPHERE AS A SOURCE OF PLANT FOOD 19.
Página 20
Alfred Vivian. obtained by increasing the carbonic acid in the air , but under field conditions the yield is limited by other factors , and never by the supply of carbon . Carbon Costs the Farmer Nothing . The point of practical ...
Alfred Vivian. obtained by increasing the carbonic acid in the air , but under field conditions the yield is limited by other factors , and never by the supply of carbon . Carbon Costs the Farmer Nothing . The point of practical ...
Página 23
... increases the rate of nitrification . Nor can these bac- teria thrive in a soil that is acid , so that the presence of carbonate of lime , or some other substance that will neutralize any acid produced in the soil , is essential to ...
... increases the rate of nitrification . Nor can these bac- teria thrive in a soil that is acid , so that the presence of carbonate of lime , or some other substance that will neutralize any acid produced in the soil , is essential to ...
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Términos y frases comunes
acid and potash acre agricultural ammonia amount of nitrogen amount of plant animals applied average bacteria barn barnyard manure bedding carbonic acid clay clover commercial fertilizers complete fertilizers composition compounds condition corn crop decay deep stall denitrification drainage dry matter elements of plant Experiment Station fact farm farmer feeding fertilizing constituents fertilizing materials fertilizing value field grain green manuring ground grown hot fermentation humus important inches increase ingredients kainite land leaching legumes leguminous lime liquid excrement loss of nitrogen lysimeters manure produced materials ments method mineral matter mixed moisture necessary nitrate of soda nitrification nitrifying bacteria nitro nitrogen nure obtained organic matter oxygen phoric acid phos phosphate phosphoric acid plant food plant growth plots plowed pounds practically present rains ration removed rock roots rotation shown soil soil contains soluble substances sufficient sulphate superphosphate supply surface tillage tion urine wheat yield