Reduced grazing pressure delivers production and environmental benefits for the typical steppe of north China.

Yingjun Zhang,David R Kemp,Nan Liu,Xiaoya Wang,Wenqing Chen,Warwick B Badgery,Ding Huang

doi:10.1038/srep16434

Abstract

Degradation by overgrazing is common in many areas of the world and optimising grassland functions depends upon finding suitable grazing tactics. This four-year study on the northern China steppe investigated combinations of rest, moderate or heavy grazing pressure early in the summer growing season, then moderate or heavy grazing in the mid and late season. Results showed that moderate grazing pressure (~550 sheep equivalent (SE) grazing days ha−1 year−1) gave the optimal balance between maintaining a productive and diverse grassland, a profitable livestock system, and greenhouse gas mitigation. Further analyses identified that more conservative stocking (~400 SE grazing days ha−1 year−1) maintained a desirable Leymus chinensis composition and achieved a higher live weight gain of sheep. Early summer rest best maintained a desirable grassland composition, but had few other benefits and reduced incomes. These findings demonstrate that reducing grazing pressure to half the current district stocking rates can deliver improved ecosystem services (lower greenhouse gases and improved grassland composition) while sustaining herder incomes.

Highlights

Discipline focus on diversity and species conservation are rarely integrated, yet the application of both are needed to find optimal solutions[11,12]
An integrated measure of the grazing pressure in each treatment was calculated as the sheep equivalent (SE) grazing days ha−1 year−1, which took into account the actual SE ha−1, variation in the duration of each grazing period and variation in these terms between years (Supplementary Table 1)
There was a strong association between SE grazing days ha−1 year−1, the growth rate of the grassland (Fig. 1a), and the proportion of the vegetation utilised by the sheep (Fig. 1b)

Summary

Introduction

Discipline focus on diversity and species conservation are rarely integrated, yet the application of both are needed to find optimal solutions[11,12]. The key techniques adopted by these policies and programs involve partial or total rests (bans) from grazing that may last for several years, the regulation and control of grazing pressure, and the cessation of transhumance grazing systems. It is unclear how these policies designed to provide benefits to the grassland environment affect households as limited monitoring has been done. To understand the underlying relationships that applied across all treatments and to identify the optimal stocking capacity of the grassland, data from across all treatments were combined and regression and multivariate methods used

Methods

Results

Conclusion