栗钙土水肥耦合效应的田间研究

A FIELD RESEARCH ON THE EFFECT OF WATER FERTILIZER COUPLING IN CHESTNUT SOIL

高寒半干旱栗钙土农田水肥耦合效应明显。供水量为２５０ ～４５０ ｍ ｍ 条件下，氮磷合理配施改善了地上部生物学性状，促进了地下部根系发育；供水３５０ ｍ ｍ Ｎ１２０ Ｐ９０ 处理０ ～４０ｃ ｍ 根重密度最高，达１３１７ ｍｇ／ｃｍ ３ ， Ｐ４５ 较 Ｎ６０ 根重密度增加００６７ ～０３７５ｍ ｇ／ｃｍ ３ 。供水为１５０ ｍ ｍ 的干旱年型，水分是限制作物生产的主导因素，而供水２５０ ～４５０ ｍ ｍ 年型主导因素则是土壤营养不足。供水量３５０ ｍ ｍ Ｎ１２０ Ｐ９０ 处理作物水分利用效率最高，可达７２７ｋｇ／（ ｍ ｍ ·ｈ ｍ ２） ， Ｎ６０ Ｐ９０ 氮肥利用率最高，子粒和植株分别为４８１８ ％ 和８８１７ ％ ， Ｎ１２０ Ｐ４５ 磷肥利用率最高，子粒和植株分别为２１１３ ％ 和３０４２ ％ 。水肥合理耦合有效地提高了作物产量和水肥利用率。

The effect of field water fertilizer coupling was very significance in chestnut soil in semi arid region with cold and high elevation. Under amounts of water supply 250～450mm, the concerted use of nitrogen and phosphate fertilizer could improve biological characteristics of aerial part, and promote root system development of subsurface part. The treatment of water supply 350mm and N 120 P 90 had the highest density of root weight which was 1 317mg/cm 3, and under water supply 250～450mm the density of root weight increased 0 067～0 375mg/cm 3 using P 45 than that N 60 . Water was the main factor limited crop productivity in dry year of water supply 150mm. In other years of water supply 250～450mm the deficient nutrition was the main limiting factor. The treatment of water supply 350mm and N 120 P 90 had the highest water use efficiency which was 7 27kg/(mm·hm 2), N 60 P 90 had the highest nitrogen use efficiency which were 48 18 and 88 17 percent seperately in grain and plant of naked oat, the highest phosphate use efficiency was in N 120 P 45 which were 21 13 and 30 42 percent seperately in grain and plant. So rational water fertilizer coupling could raised effectively the yield and water and fertilizer use efficiency.