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Fertile soils have been an essential resource for humanity for 10,000 y, but the ecological mechanisms involved in the creation and restoration of fertile soils, and especially the role of plant diversity, are poorly understood. Here we use results of a long-term, unfertilized plant biodiversity experiment to determine whether biodiversity, especially plant functional biodiversity, impacted the regeneration of fertility on a degraded sandy soil. After 23 y, plots containing 16 perennial grassland plant species had, relative to monocultures of these same species, ∼30 to 90% greater increases in soil nitrogen, potassium, calcium, magnesium, cation exchange capacity, and carbon and had ∼150 to 370% greater amounts of N, K, Ca, and Mg in plant biomass. Our results suggest that biodiversity, likely in combination with the increased plant productivity caused by higher biodiversity, led to greater soil fertility. Moreover, plots with high plant functional diversity, those containing grasses, legumes, and forbs, accumulated significantly greater N, K, Ca, and Mg in the total nutrient pool (plant biomass and soil) than did plots containing just one of these three functional groups. Plant species in these functional groups had trade-offs between their tissue N content, tissue K content, and root mass, suggesting why species from all three functional groups were essential for regenerating soil fertility. Our findings suggest that efforts to regenerate soil C stores and soil fertility may be aided by creative uses of plant diversity.
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This content will become publicly available on January 13, 2027
Insights on global rangeland ecosystem services shaped by grazing and fertilization
Rangelands are crucial to human well‐being, but their ability to provide ecosystem services is threatened. We (1) quantified key ecosystem services provided by rangelands, (2) assessed short‐ and long‐term impacts of fertilization (nutrient addition) and the exclusion of large grazing herbivores with fences (herbivore exclusion) on services, and (3) identified synergies and trade‐offs among services. We measured indicators of ecosystem services and plant diversity at 79 sites across six continents in the global Nutrient Network. Short‐term herbivore exclusion increased forage quantity and soil fertility, but longer‐term herbivore exclusion decreased both along with plant richness and pollination. Nutrient addition improved forage provisioning, soil stability, climate regulation, and control of soil erosion but lowered plant diversity and impeded delivery of related services, especially after prolonged application. We found synergies between plant diversity and pollination, as well as between soil fertility, soil stability, and climate regulation. Trade‐offs between forage stability and quality persisted after nutrient addition but disappeared with herbivore exclusion. Our results suggest that alternative management actions may sustain livestock production while maintaining rangeland ecosystem services.
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- PAR ID:
- 10664218
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Frontiers in Ecology and the Environment
- ISSN:
- 1540-9295
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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