In addition, mowing over decades can make it harder for a grassland to recover. In summer, sheep graze. In winter, they eat the cut hay. However, long-term mowing cuts off nutrient transfer from leaves to roots, weakening root systems, Xin said.
Their research is built on long-term ground observations, combined with remote sensing to monitor the productivity and degradation of grasslands. However, none of this work would be possible without fieldwork.
To study a grassland, researchers clip and weigh plant samples from fixed plots to measure not only total biomass but also species composition.
This reveals whether the pasture is dominated by quality forage or degraded weeds. They also collect fecal matter to analyze what the animals have eaten, how well they digest it, and whether nutrient deficiencies are present.
Field surveys usually run between April and September, the grassland growing season. Researchers pack scissors, drills, nylon bags, and a few days' worth of food including buns, cucumbers, tomatoes, and pickles, and then head out in an old jeep. If the car breaks down at night, they pitch a tent and sleep under the stars.
After decades of observation, they have collected over 20 million pieces of data, 23,000 soil samples, and more than 1,000 plant specimens.
Grassland covers about 30 percent of the country and helps weaken winter winds from Siberia. Healthy grassland serves as a protective barrier. The grass also protects the country from dust, Xin added.
