Despite the essential role of micronutrients in plant metabolic processes and carbon cycle, the mechanisms by which micronutrients regulate plant community traits remain poorly understood.  Here, we used a long-term experiment to explore the potential mechanisms of plant community micronutrients and traits along a precipitation gradient.  Our results showed that plants shifted toward lateral growth and asexual reproduction over time.  From 1985 to 2022, the plant community Fe content increased by 18.8% in the north but declined by 25.2% in the south of the typical steppe.  Furthermore, plant community growth and reproduction were sensitive to both micronutrient contents and uptake efficiencies in the north of the typical steppe.  While plant community Mn and Zn contents enhanced growth longitudinally, Zn and Fe uptake efficiencies hindered sexual reproduction.  Furthermore, soil moisture and GDP per capita were the key drivers of micronutrient variation in the north and south of the typical steppe, respectively.  Precipitation fluctuations primarily regulated community traits across all sites.  In the arid site, micronutrient-driven shifts in reproduction stabilized the soil carbon stock by balancing biomass allocation.  These findings can help us to better understand the coupling of plant micronutrients, traits, and soil carbon stocks, thereby providing the basis for a scientific grassland conservation strategy under global change scenarios.

Understanding livestock performance in typical steppe ecosystems is essential for optimizing grassland-livestock interactions and minimizing environmental impact.  To assess the effects of different stocking rates on the growth performance, energy and nitrogen utilization, methane (CH₄) emissions, and grazing behavior of Tan sheep, a 2-year grazing experiment in the typical steppe was conducted.  The grazing area was divided into 9 paddocks, each 0.5 ha, with 3 spatial replicates for each stocking rate treatment (4, 8, and 13 sheep per paddock), corresponding to 2.7, 5.3, and 8.7 sheep ha^–1.  The results showed that the neutral detergent fiber (NDF) and acid detergent fiber (ADF) contents of herbage varied between grazing years (P<0.05), with a positive correlation between stocking rate and crude fiber content in the herbage (P<0.05).  Dry matter intake (DMI) decreased with increasing stocking rate (P<0.05), and the average daily gain (ADG) was highest at 2.7 sheep ha^–1 (P<0.05).  Compared to 2.7 and 8.7 sheep ha^–1, the 5.3 sheep ha^–1 treatment exhibited the lowest nutrient digestibility for dry matter, nitrogen, and ether extract (P<0.05).  Fecal nitrogen was lowest at 8.7 sheep ha^–1 (P<0.05), while retained nitrogen as a proportion of nitrogen intake was highest.  Digestive energy (DE), metabolic energy (ME), and the ratios of DE to gross energy (GE) and ME to GE were highest at 8.7 sheep ha^–1 (P<0.05).  In contrast, CH₄ emissions, CH₄ per DMI, and CH₄E as a proportion of GE were highest at 2.7 sheep ha^–1 (P<0.05).  Stocking rate and grazing year did not significantly affect rumen fermentation parameters, including volatile fatty acids, acetate, propionate, and the acetate/propionate ratio.  At 8.7 sheep ha^–1, daily grazing time and inter-individual distance increased, while time allocated to grazing, walking, and ruminating/resting decreased as stocking rates increased (P<0.05).  This study highlights the importance of adjusting stocking rates based on the nutritional value of forage and grazing year to optimize grazing management.