使高兴
发表于 2025-3-23 11:47:20
Biological nitrogen fixation and soil fertility maintenance,rge quantities by growing plants and is indeed the key to soil fertility. NonN.-fixing plants—for example, cereals—take all the N they need from the soil. In Senegalese conditions this uptake was estimated to be as follows: 79–132 kg N/ha/crop for pearl millet; 74–84 for rice; 134 for sorghum; and 1
拖债
发表于 2025-3-23 14:50:26
Management of nitrogen fertilizers for tropical African soils,he degree to which the soil fertility is maintained. Nitrogen, the most mobile plant nutrient, is the most easily exhaustible nutrient element in the soil. This is particularly true in the fragile, poorly buffered soils commonly found in tropical Africa. Traditional farmers in Africa found adequate
Magisterial
发表于 2025-3-23 20:02:05
Phosphate deposits of tropical sub-Saharan Africa,pulation approaching 500 million. From north to south in a straight line, the maximum distance is about 8,000 km, and from east to west it is about 7,200 km. Although the equator cuts almost exactly midway across the continent, with about two-thirds of the total area lying between the Tropics of Can
Gustatory
发表于 2025-3-24 01:36:42
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PRO
发表于 2025-3-24 06:02:53
Agronomic evaluation of phosphate fertilizers in tropical Africa,orts have been made to (1) assess the extent of phosphorus deficiency in the soils , (2) estimate the phosphorus requirements of major food crops , and (3) evaluate the agronomic potential of various phosphate fertilizers including phosphate rock from local depo
Bridle
发表于 2025-3-24 09:04:12
Economic evaluation of alternative fertilizer technologies for tropical African agriculture,of various inputs or factors of production. The management and levels of use of these inputs depend upon the soil-agroclimatic and market (prices) environments and the crop production technology. Farmers’ decisions on the use of these inputs reflect their economic motivation in the face of physical
VEN
发表于 2025-3-24 12:04:24
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加强防卫
发表于 2025-3-24 15:19:11
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BRIBE
发表于 2025-3-24 19:52:05
John Mclntireodernité: la . avec ses évidences naïves et traditionnelles, la ., et la . et son .. Procès à double visée au cours duquel, d’une part, la raison positiviste et objectiviste moderne est mise en accusation pour avoir manqué sa vocation de donner sens à la totalité de Pexistence humaine, et d’autre pa
畸形
发表于 2025-3-25 02:56:14
H. Ssali,P. M. Ahn,A. Mokwunyeodernité: la . avec ses évidences naïves et traditionnelles, la ., et la . et son .. Procès à double visée au cours duquel, d’une part, la raison positiviste et objectiviste moderne est mise en accusation pour avoir manqué sa vocation de donner sens à la totalité de Pexistence humaine, et d’autre pa