The deserts of the Kashmir‐Tibetan frontier

Abstract

Semi-arid landscapes are vulnerable to cultivation, overgrazing and climate variability, although it is difficult to identify the relative significance of these three factors. In the South African Karoo, the ‘desertification debate' seeks to explain a change to more shrubby vegetation in heavily grazed areas. We examine these issues in catchments where farm reservoirs provide sediment stores with 137Cs, 210Pb, geochemical and mineral magnetic signatures. Rainfall data and stocking numbers are reported and current erosion rates are estimated. Sediment accumulation in the reservoirs increases between 1935 and 1940, probably due to rises in the frequency of rainfall events of >25mm day. Significant increases in sedimentation rates (×8) occur during rain-fed wheat cultivation. In an uncultivated catchment, sediment yields remain relatively high and reflect increases in erosion from hillslopes, colluvial storage, and cultivated land sources. Gully systems have acted as transport routes rather than sediment sources over the last ～70 years. Badland erosion rates average ca. 50t ha^?1 yr^?1. At Ganora, their development in the 1920s strongly influences peak sedimentation between 1970 and 1980. Any delay between badland initiation and increased sediment yield appears to be a function of landscape connectivity. Recovery following disturbance is occurring slowly and is likely to take >100 years. De-stocking and better management systems are reducing erosion rates but may be offset by increases in rainfall intensity.     

Educational and other books received

SCOTLAND

A Development Plan for Scotland. By G. McRobbie. Planning. Vol. XXIX No. 476. 8 ½×5 ½. Pp. 30. London: Political and Economic Planning, 1963. 4s. 6d.

The Contour Road Book of Scotland. By H. R. G. Inglis, revised and extended by R. M. G. Inglis. 6 ½ × 3 ½. Pp. 28 + xx + 288 + 16. 4 pages of black and white maps. 24 pages of coloured maps. 146 pages of profile diagrams. Edinburgh: Gall &; Inglis, 1963. 8s. 6d.

The Highlands and Islands of Scotland. By A. C. O'Dell and K. Walton. 9 ¾ × 6 ¼. Pp.xii+ 353. One folding coloured map. 49 plates. 94 figures. Edinburgh: Thomas Nelson &; Sons Ltd., 1962. 50s.

Scotland's Eastern Coast. By L. Scott‐Moncrieff. 8 ¾ × 5 ½. Pp. xiv + 214. 41 plates. 2 end‐paper maps. Edinburgh: Oliver &; Boyd, 1963. 25s.

The Fortified House in Scotland. Volume Two, Central Scotland. By N. Tranter. 8 ½ × 5 ½. Pp. 183. 97 drawings. Edinburgh: Oliver &; Boyd, 1963. 25s.     

Natural flood management: small-scale progress and larger-scale challenges

ABSTRACT

Management of fluvial flood risk in the UK is undergoing a paradigm shift, with a change in emphasis from solely working with structural defences to considering catchment-based measures which attenuate flood runoff. Natural Flood Management (NFM) is promoted as a method that can reduce flood risk through the alteration, restoration or use of landscape features. Here we highlight the potential to manage runoff locally in the rural landscape using NFM by targeting flow pathways and utilising floodplains and riparian zones. Using two case study examples from the UK, we show that by accumulating dispersed small-scale storage in small catchment areas (<10 km²) can assist in attenuating flood runoff. However, there is currently a lack of evidence of measure effectiveness at larger catchment scales and for managing extreme flood events. Nevertheless, there is a strong evidence base to suggest many of these measures deliver a range of different ecosystem services if installed in the correct location in the landscape.