Regionalisation of suitable herbages for grassland reconstruction in agro-pastoral transition zone of northern China

To provide a sound basis for selecting suitable herbages for grassland reconstruction in the farming-pastoral zone of northern China, the zone was divided into regions using the lowest annual temperature, water regimes represented by a moisture index (the ratio between annual rainfall and accumulated temperature > 0 degrees C), soil types, and terrain. Suitable herbages of Gramineae (G), Leguminosae (L) and other families (0), representing native species (NS) and non-native cultivars (CR) were recommended for the zone based on the following four principles: a) matching species with the site; b) giving precedence to ecological conservation; c) providing economic benefit to production; and d) taking into account the integrity of local administrative division. The main findings from this study were as follows. The farming-pastoral zone was divided into seven regions: I. Western Songliao Plain and Daxinganling Mountain Region; II. Upper Liaohe River Sandy Region; III. Mid-Eastem Mongolia Plateau and Northwestern Heibei Mountain Region; IV. Luliang, Taihang and Yanshan Mountains Region; V. Ordos Plateau Sandy Region; VI. Northern Shaanxi to Eastern Gatixu Loess Plateau Region; and VII. Mid Gansu to Eastern Qinghai Plateau Loess Region. Among the herbages recommended for selection, Stipa grandis and Levinus chinensis were particularly suggested for controlling wind erosion in Region I; Levinus chinensis and Elymus dahuricus for lessening soil alkalisation in Region II; Stipa glareos, Elymus dahuricus and Agropyron desertorinn for retarding land desertification in Region III; Elymus nutans and Bromus inermis for preventing water erosion in Region IV, Agropyron desertorum and Elymus dahuricus for reducing wind erosion and land desertification for Region V, Medicago sativa and Onobrychis viciaefolia for improving soil fertility in Region VI; Medicago varia and Melilotoides rethenica for controlling erosion and improving soil fertility in Region VII.