Effects of urea amended with urease and nitrification inhibitors on soil nematode communities were studied in a Hapli- Udic Argosol （Cambisol, FAO） in Liaoning Province of Northeast China. A completely random design...Effects of urea amended with urease and nitrification inhibitors on soil nematode communities were studied in a Hapli- Udic Argosol （Cambisol, FAO） in Liaoning Province of Northeast China. A completely random design with four treatments, i.e., conventional urea （CU）, slow-release urea amended with a liquid urease inhibitor （SRU1）, SRU1 ＋nitrification inhibitor dicyandiamide （SRU2）, and SRU1 ＋ nitrification inhibitor 3,5-dimethylpyrazole （SRU3） and four replicates were applied. Thirty-nine genera of nematodes were identified, with Cephalobus and Aphelenchus being dominant; and in all treatments, the dominant trophic group was bacterivores. In addition, during the growth period of spring wheat （Triticum aestivum L.）, soil urease activity was lower in SRUs than in CU. The numbers of total nematodes and bacterivores at wheat heading and ripening stages, and omnivores-predators at ripening stage were higher in SUR3 than in CU, SRU1 and SRU2 （P 〈 0.05）.展开更多
对黑土(简育湿润均腐土)长期定位施肥15年后土壤磷素形态进行分析研究。结果表明:土壤中积累的Al-P、Ca2-P量与施磷量成正相关;只施NK能促进植物对Ca8-P的吸收;闭蓄态磷(Oc-P)含量均较低。施磷肥能增加黑土Fe-P含量,却未能增加Ca10-P含...对黑土(简育湿润均腐土)长期定位施肥15年后土壤磷素形态进行分析研究。结果表明:土壤中积累的Al-P、Ca2-P量与施磷量成正相关;只施NK能促进植物对Ca8-P的吸收;闭蓄态磷(Oc-P)含量均较低。施磷肥能增加黑土Fe-P含量,却未能增加Ca10-P含量。黑土各形态无机磷的含量大小顺序为:Fe-P>Ca10-P>Al-P>Ca8-P>Ca2-P>Oc-P。施磷能增加土壤中有机磷(O-P)的含量,但不能增加土壤有机质含量。土壤有机质含量均有不同程度的下降。本试验黑土中施入N 112.5 kg hm-2a-1和P 20 kg hm-2a-1能保持土壤中无机磷(I-P)平衡。展开更多
基金Project supported by the National Key Basic Research Support Foundation of China (No. 2005CB121105) and the National High Technology Research and Development Program of China (No. 2005AA001480).
文摘Effects of urea amended with urease and nitrification inhibitors on soil nematode communities were studied in a Hapli- Udic Argosol （Cambisol, FAO） in Liaoning Province of Northeast China. A completely random design with four treatments, i.e., conventional urea （CU）, slow-release urea amended with a liquid urease inhibitor （SRU1）, SRU1 ＋nitrification inhibitor dicyandiamide （SRU2）, and SRU1 ＋ nitrification inhibitor 3,5-dimethylpyrazole （SRU3） and four replicates were applied. Thirty-nine genera of nematodes were identified, with Cephalobus and Aphelenchus being dominant; and in all treatments, the dominant trophic group was bacterivores. In addition, during the growth period of spring wheat （Triticum aestivum L.）, soil urease activity was lower in SRUs than in CU. The numbers of total nematodes and bacterivores at wheat heading and ripening stages, and omnivores-predators at ripening stage were higher in SUR3 than in CU, SRU1 and SRU2 （P 〈 0.05）.
文摘对黑土(简育湿润均腐土)长期定位施肥15年后土壤磷素形态进行分析研究。结果表明:土壤中积累的Al-P、Ca2-P量与施磷量成正相关;只施NK能促进植物对Ca8-P的吸收;闭蓄态磷(Oc-P)含量均较低。施磷肥能增加黑土Fe-P含量,却未能增加Ca10-P含量。黑土各形态无机磷的含量大小顺序为:Fe-P>Ca10-P>Al-P>Ca8-P>Ca2-P>Oc-P。施磷能增加土壤中有机磷(O-P)的含量,但不能增加土壤有机质含量。土壤有机质含量均有不同程度的下降。本试验黑土中施入N 112.5 kg hm-2a-1和P 20 kg hm-2a-1能保持土壤中无机磷(I-P)平衡。
