EFFECT OF THE STOCKING RATE AND LAND SLOPE ON NITROGEN LOSSES TO WATER ON A GRAZED PASTURE OF SOUTHERN CHILE
EFFECT OF THE STOCKING RATE AND LAND SLOPE ON NITROGEN LOSSES TO WATER ON A GRAZED PASTURE OF SOUTHERN CHILE
复制标题
智利南部放牧草地放养率和土地坡度对水氮流失的影响
DOI：
10.4067/s0718-95162011000200009
复制
发表时间：
2011
影响因子：
3.9
通讯作者：
L. Ramírez
中科院分区：
文献类型：
--
作者：
F. Salazar;M. Alfaro;S. Ledgard;S. Iraira;N. Teuber;L. Ramírez
大部分的氮（N）淋溶的研究已经进行了切割草，并有一个牛肉放牧草地的信息缺乏。本研究的目的是量化的N径流和淋溶损失的牛肉生产系统，两种不同的直接放养率（63和191荷斯坦黑白花牛-1公顷-1天-1）和两个土地坡度（4和12%）。径流和渗滤液样品进行了分析，从2004年至2006年的总氮，硝酸盐和铵。氮素总损失量在处理间差异不显著（p > 0.05），在0.9 ~ 26.8kgNha-1/yr-1范围内变化较小。氮素流失的主要途径是淋溶，淋溶量占氮素流失总量的99%以上。氮素淋失的主要形态为硝态氮（>84%）。径流样品中硝态氮含量较高，平均为14 ~ 31 mg L-1。我们认为，这些低N损失可能与低N肥料投入的牧场和火山岩土壤的N吸附性能，因此，需要进一步研究这个问题。
Most of the studies on nitrogen (N) leaching have been carried out on cut grass, and there is a lack of information on beef grazed grasslands. The objective of this study was to quantify N runoff and leaching losses in beef production systems with two different immediate stocking rates (63 and 191 Holstein Friesian steers ha -1 day -1 ) and two land slopes (4 and 12%). Runoff and leachate samples were analyzed from 2004 to 2006 for total N, nitrate and ammonium. No significant differences for the total N losses were found between treatments (p > 0.05), which were low ranging from 0.9 to 26.8 kg N ha -1 yr -1 . The main pathway for the losses was leaching, which contributed >99% of the total N lost. The main form of N leaching was nitrate-N (>84%). Nitrate-N concentration in runoff samples was high, averaging 14 to 31 mg L -1 . We suggest that these low N losses could be related the low N fertiliser inputs in the pasture and to the N adsorption properties of volcanic soils and, so that further research is required on this subject.