Li L.,Gansu Agricultural University |
Chan K.Y.,Investment and Industry NSW |
Niu Y.,Gansu Agricultural University |
Li G.,Charles Sturt University |
And 3 more authors.
Soil and Tillage Research | Year: 2011
The common soil physical quality indicators are related to each other because they all reflect soil structure, but to measure all of these parameters would be very time consuming. Therefore, it is desirable to obtain one simple index for overall assessment. The soil physical parameter, S, may serve this purpose but the theory needs to be validated on soils affected by different management practices. Therefore, in this paper, soils from a long-term tillage/stubble experiment which commenced in 1979 in New South Wales, Australia were analysed for treatment effects on aspects of soil physical quality and on the S value. The treatments ranged from direct-drilling, stubble-retention through to multiple-cultivation stubble-burnt and also included a wheel track vs. non-wheel track comparison. Results showed that after 26. years of different tillage and stubble management practices, significant changes in soil physical qualities were detectable at 0.05. m depth. The direct-drilling soil had lower bulk density, higher soil organic carbon and improved water-stable aggregation (>0.25. mm aggregates) and friability. The S values obtained from the soil water retention curves were well correlated with the other soil physical quality indicators determined in this research and covered the range of S values from 0.030 to 0.046 associated with soil physical qualities in the poor and good categories. It is concluded that S value can be used as an overall index of soil physical quality for soils under different tillage, stubble and field traffic treatments. © 2011 Elsevier B.V. Source
Li L.-L.,Gansu Agricultural University |
Huang G.-B.,Gansu Agricultural University |
Zhang R.-Z.,Gansu Agricultural University |
Bill B.,University of Western Sydney |
And 2 more authors.
Agricultural Sciences in China | Year: 2011
Conservation agriculture has been practised for three decades and has been spread widely. There are many nomenclatures surrounding conservation agriculture and differ to each other lightly. Conservation agriculture (CA) is a system approach to soil and water conservation, high crop productivity and profitability, in one word, it is a system approach to sustainable agriculture. Yet, because conservation agriculture is a knowledge-intensive and a complex system to learn and implement, and also because of traditions of intensive cultivation, adoption rates have been low, since to date, only about seven percent of the world's arable and permanent cropland area is farmed under conservation agriculture. The practice and wider extention of conservation agriculture thus requires a deeper understanding of its ecological underpinnings in order to manage its various elements for sustainable intensification, where the aim is to conserve soil and water and improve sustainability over the long term. This paper described terms related to conservation agriculture, presented the effects of conservation agriculture on soil and water conservation, crop productivity, progress and adoption of CA worldwide, emphasized obstacles and possible ways to increase CA adoption to accelerate sustainable development of China agriculture. © 2011 Chinese Academy of Agricultural Sciences. Source