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Nutrient augmentation is one major global change disturbance that could have cascading effects on local plant and microbial communities thus altering biogeochemical properties (Peñuelas et al. 2012). While many studies have investigated fertilization effects on community change and ecosystem processes, less work has been done in dryland ecosystems (Schimel 2010), where nutrient availability often comes as pulses correlated with rain events (Collins et al. 2008). We leveraged an ongoing fertilization experiment (NutNet) at the Sevilleta to answer the question: How does fertilization alter dryland biogeochemical processes, and how does this effect change seasonally? To explore this topic, we specifically measure three important soil hydrolase enzymes, N-acetyl- glycosaminidase (NAG), phosphatase (AP), and β- glucosidase (BG), microbial biomass, and soil nitrogen levels at 5 points along a seasonal gradient within the NutNet plots.
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Micronutrients enhance macronutrient effects in a meta‐analysis of grassland arthropod abundance
Aim: Ongoing alterations to Earth’s biogeochemical cycles (e.g., via fertilization, burning of fossil fuels, and pollution) are expected to impact plants, plant consumers and all subsequent trophic levels. While fertilization experiments often reveal arthropod nutrient limitation by nitrogen and phosphorus via effects on plant nutrient density and biomass, these macronutrients are only two of many nutrients important to arthropod fitness. Micronutrients are key to osmoregulation and enzyme function and can interact synergistically with macronutrients to shape the geography of arthropod abundance. We examine arthropod response to macro- and micronutrient fertilization as a function of nutrient type, application amount, duration, frequency, and plant responses to fertilization with the goal of addressing how ongoing alterations to biogeochemical cycles will shape future grassland food webs.
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- PAR ID:
- 10198396
- Date Published:
- Journal Name:
- Global Ecology and Biogeography
- ISSN:
- 1466-822X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1111/geb.13196
