Knowledge Resource Center for Ecological Environment in Arid Area
DOI | 10.1071/EA9960937 |
Nitrogen supply to no-tillage crops, as influenced by mulch type, soil type and season, following pasture leys in the semi-arid tropics | |
Dimes, JP; McCown, RL; Saffigna, PG | |
通讯作者 | Dimes, JP |
会议名称 | Workshop on Conservation Farming for the Semi-Arid Tropics |
会议日期 | JUL 18-20, 1995 |
会议地点 | KATHERINE, AUSTRALIA |
英文摘要 | Past cropping research in the semi-arid tropics of northern Australia has shown that in this climate and on the predominantly sesquioxidic soils, recovery of fertiliser nitrogen (N) by crops is often low. Conceptually, no-tillage, legume ley farming offers features for coping better with the constraints of climate, soil and high fertiliser transport costs to this remote region. This paper summarises the N cycle in a system in which pastures provide N for successive crops, and mulch at the time of crop establishment is provided by the killing of new pasture growth. The aim was further to provide a sound foundation for managing N supply in relation to demand in a climate that causes high variation and uncertainty for pasture N-2 fixation and sequestering, the amount of early season re-growth (mulch), rate of mulch decomposition, nitrate leaching losses, and crop growth and N demand. The research approach combined field studies with simulation modelling. A series of field studies that included bare fallow and grass and legume pasture leys on clay loam and sandy loam soils, were conducted at Katherine over 4 wet seasons to study subsequent mineralisation of N. Experimental results were used to test the performance of a simulation model for predicting the observed variations consequent upon the various management options. Experimental results showed that the carbon (C):N ratio of the residue and soil texture were important factors in determining N mineralisation, immobilisation, and nitrate leaching following chemical kill of pasture leys. However, the greatest variation was between seasons. A modified version of the CERES-Maize N model was able to simulate the accumulation of nitrate following a bare fallow and following pasture leys with high levels (above and below ground) of freshly killed residues with widely differing C:N ratio, the downward movement of nitrate-N in the soil and the interaction of these processes with seasonal rainfall. Despite a capability for simulation of the soil N dynamics in a cropping phase following pasture leys, experimental results indicated how nitrate distribution following leys is influenced by pasture growth during the ley, and how this varied greatly with season and soil texture. The simulation capability reported here has been incorporated elsewhere into the development of a full system model, embracing both the ley phase and the crop phase. |
来源出版物 | AUSTRALIAN JOURNAL OF EXPERIMENTAL AGRICULTURE |
ISSN | 0816-1089 |
出版年 | 1996 |
卷号 | 36 |
期号 | 8 |
页码 | 937-946 |
出版者 | C S I R O PUBLICATIONS |
类型 | Article;Proceedings Paper |
语种 | 英语 |
国家 | AUSTRALIA |
收录类别 | CPCI-S ; SCI-E |
WOS记录号 | WOS:A1996WL12300004 |
WOS关键词 | FERTILIZER |
WOS类目 | Agriculture, Multidisciplinary |
WOS研究方向 | Agriculture |
资源类型 | 会议论文 |
条目标识符 | http://119.78.100.177/qdio/handle/2XILL650/291427 |
作者单位 | (1)APSRU,CSIRO,DIV TROP CROPS & PASTURES,TOOWOOMBA,QLD 4350,AUSTRALIA;(2)GRIFFITH UNIV,SCH ENGN,GOLD COAST MAIL CTR,GOLD COAST,QLD 4217,AUSTRALIA |
推荐引用方式 GB/T 7714 | Dimes, JP,McCown, RL,Saffigna, PG. Nitrogen supply to no-tillage crops, as influenced by mulch type, soil type and season, following pasture leys in the semi-arid tropics[C]:C S I R O PUBLICATIONS,1996:937-946. |
条目包含的文件 | 条目无相关文件。 |
除非特别说明,本系统中所有内容都受版权保护,并保留所有权利。