农业废弃物育苗基质对红叶石楠氮磷径流流失的影响

将农业废弃物作为基质的主要原料进行育苗是目前处置废弃物及促进苗木生长的双赢措施,但前期研究并未关注农业废弃物对苗木生长期间氮磷流失的影响。选用2种育苗基质,通过建设野外径流场,研究传统基质1(木屑与水洗牛粪等组成)与新型基质2(腐熟枝叶与山核桃壳等组成)育苗条件下,容器苗氮磷流失通量与红叶石楠生长情况。结果表明,施肥后1个月是控制苗木氮磷流失的关键时期,2种基质育苗条件下,TN、NH4+-N与NO3–-N径流流失通量无显著性差异,但基质2中TP与PO34-流失通量显著高于基质1。红叶石楠生物量表现为基质2显著大于基质1。因此,新型育苗基质可作为传统基质的替代品,投入到大规模的红叶石楠育苗生产中,但须对氮磷特别是磷素用量进行控制,以减少苗圃氮磷流失。

Effects of Nursery Substrate with Agricultural Wastes on Nitrogen and Phosphorus Runoff During the Growth of Photinia frasery

Using the agricultural wastes as the major materials of nursery substrates could not only promote the disposal rate of the wastes but also improve the seedlings’ growth.However,effects of the nursery substrate with agricultural wastes on nitrogen(N) and phosphorus(P) losses hasn’t been focused on.The runoff plots were conducted to research N and P runoff losses and Photinia frasery growth with two different substrates.The first substrate was made up of cow dung and filings,and so on,the other one was made up of branches,leaves and pecan shell,and so on.The results showed that one month after fertilization was the key period to control the N and P losses.There were no significant differences in TN,NH+4-N and NO–3-N loss fluxes between the two substrates.However,TP and PO3-4 loss fluxes were significantly higher in the second substrate than it in the first one.The second substrate improved the biomass of Photinia frasery,therefore,the nursery substrate made of branches,leaves and pecan shell,and so on,could be applied to grow seedlings after reducing N and P,especially P inputs.