The decreasing of the plant available phosphorus of Romanian soils after 1990 is a major concern in relation with the lowered yields of the major crops. This fact is correlated with a rudimentary technology where the ...The decreasing of the plant available phosphorus of Romanian soils after 1990 is a major concern in relation with the lowered yields of the major crops. This fact is correlated with a rudimentary technology where the fertilization is a secondary issue. Thus, the fertilizer consumption, after 1990, has drastically decreased to 41.3 kg/ha NPK on arable land over 129.9 kg/ha in 1986 and from 86.4 kg/ha to 26.3 kg/ha on agricultural land. As a result, the phosphorus fertilizer quantities applied by small farmers are very small or inexistent. In order to determine the soil available phosphorus content in Romania, it was analyzed the evolution of soil phosphorus supplying degree on a cambic chernozem （one of the most fertile soils in Romania） from Agricultural Research and Development Station （ARDS） Caracal between 1986-1992 and 2000-2005. This analysis has shown the following issues： very well supplied soils by available phosphorus no more exist since 2006, the ones with a good supplying degree have decreased from 616 ha to 107 ha, which means from 24.8% to 4.3% yet the low supplied soils have increased from 526 ha to 1,129 ha （23.1% to 45.5%） and the very low supplied ones have increased from 198 ha to 776 ha （7.9% to 31.2%）. As a consequence of low fertilizer quantities and the decreasing of the soil supplying degree by available phosphorus the average yield in this farm has decreased from 5,776 to 3,707 kg/ha.展开更多
文摘The decreasing of the plant available phosphorus of Romanian soils after 1990 is a major concern in relation with the lowered yields of the major crops. This fact is correlated with a rudimentary technology where the fertilization is a secondary issue. Thus, the fertilizer consumption, after 1990, has drastically decreased to 41.3 kg/ha NPK on arable land over 129.9 kg/ha in 1986 and from 86.4 kg/ha to 26.3 kg/ha on agricultural land. As a result, the phosphorus fertilizer quantities applied by small farmers are very small or inexistent. In order to determine the soil available phosphorus content in Romania, it was analyzed the evolution of soil phosphorus supplying degree on a cambic chernozem （one of the most fertile soils in Romania） from Agricultural Research and Development Station （ARDS） Caracal between 1986-1992 and 2000-2005. This analysis has shown the following issues： very well supplied soils by available phosphorus no more exist since 2006, the ones with a good supplying degree have decreased from 616 ha to 107 ha, which means from 24.8% to 4.3% yet the low supplied soils have increased from 526 ha to 1,129 ha （23.1% to 45.5%） and the very low supplied ones have increased from 198 ha to 776 ha （7.9% to 31.2%）. As a consequence of low fertilizer quantities and the decreasing of the soil supplying degree by available phosphorus the average yield in this farm has decreased from 5,776 to 3,707 kg/ha.
