Question

Why do temperate grasslands have higher ANPP than deserts but lower C stocks?

Answer 1

Aboveground net primary productivity (ANPP) depends upon the precipitation factor. Precipitation plays a huge role in controlling the primary production of grasslands. ANPP depends a lot on mean annual precipitation and precipitational seasonal distribution. With increase in precipitational seasonal distribution (PSD), the ANPP increases. Thus, PSD in temperate grasslands are higher compared to deserts, which inturn increase ANPP.

Carbon stocks of the soil is effected by grazing and species composition. In deserts these are absent and thus does not effect carbon stocks in soil. In grasslands, grazing is active and species composition is comparitively higher, thus these two factors decrease the carbon stock in the grassland soil.