The study by Sala et al. (1986) examines the primary production of grasslands in the Central Grassland region of the United States, focusing on the influence of annual precipitation and soil characteristics. Data from 9500 sites were analyzed to understand the spatial and temporal patterns of aboveground net primary production (ANPP). The results show that ANPP is strongly influenced by water availability, with the highest values observed in the eastern part of the region and the lowest in the western part. The spatial pattern of ANPP reflects an east-west gradient in annual precipitation, with production decreasing towards the north and south during unfavorable years and increasing towards the west during favorable years. Variability in ANPP among years is maximum in northern New Mexico and southwestern Kansas and decreases towards the north and south. At the site level, ANPP is explained by annual precipitation, soil water-holding capacity, and their interaction. The study supports the inverse texture hypothesis, suggesting that in dry regions, sandy soils with low water-holding capacity are more productive than loamy soils with high water-holding capacity, while the opposite pattern occurs in wetter regions. The findings highlight the importance of water availability and soil characteristics in determining primary production in grasslands.The study by Sala et al. (1986) examines the primary production of grasslands in the Central Grassland region of the United States, focusing on the influence of annual precipitation and soil characteristics. Data from 9500 sites were analyzed to understand the spatial and temporal patterns of aboveground net primary production (ANPP). The results show that ANPP is strongly influenced by water availability, with the highest values observed in the eastern part of the region and the lowest in the western part. The spatial pattern of ANPP reflects an east-west gradient in annual precipitation, with production decreasing towards the north and south during unfavorable years and increasing towards the west during favorable years. Variability in ANPP among years is maximum in northern New Mexico and southwestern Kansas and decreases towards the north and south. At the site level, ANPP is explained by annual precipitation, soil water-holding capacity, and their interaction. The study supports the inverse texture hypothesis, suggesting that in dry regions, sandy soils with low water-holding capacity are more productive than loamy soils with high water-holding capacity, while the opposite pattern occurs in wetter regions. The findings highlight the importance of water availability and soil characteristics in determining primary production in grasslands.