China possesses vast grassland resources that include alpine meadow, tundra, steppe and desert. It is, therefore, desirable to establish a grassland classification system that involves the formative factors contributing to this diversity. This paper reports a grassland classification system called the Integrated Orderly Classification System of Grassland (IOCSG), which was formulated through grouping or clustering units with similar properties. The IOCSG involves a hierarchy of three classification levels. At the first level, grasslands are grouped into classes according to an index of moisture and temperature. At the second level, grasslands are differentiated as subclasses by the edaphic conditions. At the third level, grassland types within a subclass are distinguished by vegetation types. Under the IOCSG, seven thermal zones and six humidity zones have been identified and used to differentiate grassland classes. The IOCSG recognises 42 grassland Classes, of which 41 are present in China.

The integrated crop-livestock production system provides most of the food needed by the people of China. Five types of integrated production systems are recognised; rangeland, grain crops, crop/pasture, agro-silvopastoral and ponds. Development of more sustainable and integrated crop-pasture-rangeland-livestock production systems has been recently achieved. Demonstrations of the integrated systems at household, village and regional levels are occurring for rain-fed agriculture on the Loess Plateau, the Hexi Corridor, north-western China and the Karst region of Guizhou Province, south-western China. These indicate that integration of crop, livestock and forage are effective means of improving agricultural productivity, environmental sustainability and farmers’ incomes. Widespread adoption of integrated farming systems should also reduce rangeland degradation.

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Core Ideas The similarity between SFCC and SWCC, and hysteresis of SFCC are reviewed. The SFCC and SWCC of two fine‐grained soils are measured and analyzed. No quantitative similarity is found between the measured SFCC and SWCC. Several concerns regarding the similarity between SFCC and SWCC are discussed. The drying–wetting and freezing–thawing cycles significantly influence the soil pore water in the vadose zone in permafrost and seasonally frozen regions. The soil‐freezing characteristic curve (SFCC) describes the relationship between unfrozen water content and subzero temperature in a soil at frozen condition. Several studies suggest that the SFCC of a frozen saturated soil is similar to soil‐water characteristic curve (SWCC), which describes the relationship between water content and suction for a soil under unfrozen unsaturated condition. In the present study, the similarity between SFCC and SWCC, and possible reasons for the hysteresis of SFCC are succinctly reviewed. The SFCC and SWCC of two Canadian soils were measured and critically interpreted to understand the fundamental behavior of SFCC in comparison with the SWCC. The observed hysteresis of SFCC for the two soils was mainly associated with the supercooling of pore water. The measured SFCC and SWCC of the two soils show quantitative dissimilarity rather than similarity. This may be attributed to the experimental limitations and possible fundamental differences between drying–wetting and freezing–thawing processes. In addition, several concerns regarding the similarity between SFCC and SWCC are discussed. The present study highlights that rigorous investigations are required for better understanding the SFCC to facilitate its use for cold‐region engineering practice applications.