Time filter

Source Type

Paltridge N.G.,University of Adelaide | Paltridge N.G.,Flinders University | Grover S.P.P.,Landcare Research | Gouyi L.,Tibet Agricultural Research Institute | And 4 more authors.
Plant and Soil | Year: 2011

Little is known about the soils that support agriculture in Tibet. The aim of this paper is to investigate the physical and chemical properties of Tibet's agricultural soils, the nutritional status of wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.) crops, and the sustainability of current soil management practices. Physical descriptions of Tibet's agricultural soils were based on soil pits dug at three locations across Tibet's agricultural zone. Chemical analyses were conducted on soils from seven sites across the zone. Nutritional constraints to agriculture were identified through leaf tissue tests on wheat and barley crops from 23 fields. These results, combined with published information on farm inputs and yields, provided insight into the sustainability of current nutrient practice. Soils were found to be silty or sandy clay loams with alkaline reaction, low organic content and low K and Zn status. Leaf analysis revealed one third to one half of cereal crops were marginal or deficient for K, Zn and Mg. Most farmers export grain and import only nitrogenous and phosphatic fertilizers leading to a nutrient imbalance. A balanced fertilizer program is required to halt nutrient depletion and increase grain production. Reduced tillage and crop residue retention are needed to improve soil health. © 2011 Springer Science+Business Media B.V.

Paltridge N.G.,University of Adelaide | Coventry D.R.,University of Adelaide | Tao J.,Tibet Agricultural Research Institute | Heath T.J.,University of Adelaide | Tashi N.,Tibet Agricultural Research Institute
Agronomy Journal | Year: 2014

In the river valleys of central Tibet, farming households are active in both crop and livestock production. The emphasis is mostly placed on optimizing grain production for subsistence purposes, with little emphasis on forage production to meet livestock diets. Temperatures and rainfall favor crop growth from April to October and, with crops harvested in July or August, sufficient moisture, heat, and light resources remain unused after forage harvest. Here we report data from crop-forage intercrop experiments that evaluated the role of using vetch (Vicia sativa L.) and lucerne (Medicago sativa L.) established by either broadcast or seeding in inter-row spaces of cereal crops. Broadcasting vetch in early July into maturing winter sown wheat (Triticum aestivum L.) allows useful amounts of vetch forage (3 Mg ha-1) produced for little extra work with minimal grain yield penalty. The approach of sowing vetch in the inter-row space of widely spaced winter wheat or barley (Hordeum vulgare L.) was a reliable way of establishing this forage crop. However, grain yield losses (P ≤ 0.05) of approximately 16, 22, and 37% were associated with the wider row spacing (66, 50, and 33% wheat) when vetch was grown in the inter-row space. Based on land equivalent ratios (LERs) alone, the 33% cereal density was most productive (P ≤ 0.05). However, improved understanding of forage, dairy products, and grain markets, and of the household economy on typical Tibetan farms, will be required before judgments can be made about whether farmers can profit from such intercropping approaches. © 2014 by the American Society of Agronomy, 5585 Guilford Road, Madison, WI 53711. All rights reserved.

Loading Tibet Agricultural Research Institute collaborators
Loading Tibet Agricultural Research Institute collaborators