The reserve of soil nutrients is limited. In case of irrational use of land, nutrients would be depleted sooner. Before the 1950s the low grain production in China was maintained only by expanding the cultivated area ...The reserve of soil nutrients is limited. In case of irrational use of land, nutrients would be depleted sooner. Before the 1950s the low grain production in China was maintained only by expanding the cultivated area and by recycling of nutrients in agriculture. Calculation of nutrients balance showed that in the year of 1949 there were great deficits of N, P and K elements in agriculture of China. It revealed that there would have really been danger of soil nutrients exhaustion if such a situation had continued. Things have changed since the beginning of 1950s. The nutrients balance in agriculture has been getting better and better. In the year 1987 N and P balance got rid of their great deficits. But for K the deficit grew even larger. This resulted in a rapid expansion of soil area deficient in K in China since the mid 1970s. In spite of the fact that the P balance in the arable land of the whole country was positive, the field which did not receive P fertilizer had become deficient in P. So the area deficient in P also increased. It is stressed that great attention should be paid to the depletion of soil nutrients, especially K in the northern part of China where the soil is relatively rich in K. Of course, soil sulfur and microelements should be considered next.展开更多
The study was undertaken to assess the inorganic fertilizer production and consumption, export and import trends in Nigeria, assess the effect of food legume technology on farmers＇output, income, household inventorie...The study was undertaken to assess the inorganic fertilizer production and consumption, export and import trends in Nigeria, assess the effect of food legume technology on farmers＇output, income, household inventories and inorganic fertilizer usage. Multi-stage sampling technique procedure was adopted in obtaining 300 respondents. Primary and secondary data were used. Simple descriptive statistics, t-test and correlation were used to analyse the data. Both the trend analysis result and test of mean differences showed a wide gap. The result revealed a significant increase in the yields of maize, millet, cocoyam, sweet potato, okro, tomato and overall aggregate crop yield of farmers after the adoption of the food legume technology （t = 2.78, 2.23, 3.70, 3.30, 2.20, 3.5 and 2.297; P 〈 0.05）, hence improves food security. Similarly, the result revealed significant positive change in terms of farmers＇ownership of house, increase in the number of rooms, improvement in water source, possession of radio, television/tape recorders and cell phone. Major constraints to production as revealed by the study include pests and diseases, low soil fertility, inadequate finance, storage problem and poor market for products. The study recommends adequate and regular supply of food legume production inputs to farmers and intensive control of pests and diseases.展开更多
文摘The reserve of soil nutrients is limited. In case of irrational use of land, nutrients would be depleted sooner. Before the 1950s the low grain production in China was maintained only by expanding the cultivated area and by recycling of nutrients in agriculture. Calculation of nutrients balance showed that in the year of 1949 there were great deficits of N, P and K elements in agriculture of China. It revealed that there would have really been danger of soil nutrients exhaustion if such a situation had continued. Things have changed since the beginning of 1950s. The nutrients balance in agriculture has been getting better and better. In the year 1987 N and P balance got rid of their great deficits. But for K the deficit grew even larger. This resulted in a rapid expansion of soil area deficient in K in China since the mid 1970s. In spite of the fact that the P balance in the arable land of the whole country was positive, the field which did not receive P fertilizer had become deficient in P. So the area deficient in P also increased. It is stressed that great attention should be paid to the depletion of soil nutrients, especially K in the northern part of China where the soil is relatively rich in K. Of course, soil sulfur and microelements should be considered next.
文摘The study was undertaken to assess the inorganic fertilizer production and consumption, export and import trends in Nigeria, assess the effect of food legume technology on farmers＇output, income, household inventories and inorganic fertilizer usage. Multi-stage sampling technique procedure was adopted in obtaining 300 respondents. Primary and secondary data were used. Simple descriptive statistics, t-test and correlation were used to analyse the data. Both the trend analysis result and test of mean differences showed a wide gap. The result revealed a significant increase in the yields of maize, millet, cocoyam, sweet potato, okro, tomato and overall aggregate crop yield of farmers after the adoption of the food legume technology （t = 2.78, 2.23, 3.70, 3.30, 2.20, 3.5 and 2.297; P 〈 0.05）, hence improves food security. Similarly, the result revealed significant positive change in terms of farmers＇ownership of house, increase in the number of rooms, improvement in water source, possession of radio, television/tape recorders and cell phone. Major constraints to production as revealed by the study include pests and diseases, low soil fertility, inadequate finance, storage problem and poor market for products. The study recommends adequate and regular supply of food legume production inputs to farmers and intensive control of pests and diseases.
