Recovery from disturbance requires resynchronization of ecosystem nutrient cycles

Area of Science:

• Ecology
• Biogeochemistry
• Ecosystem Dynamics

Background:

• Nitrogen (N) and phosphorus (P) cycles are tightly linked in terrestrial ecosystems, driven by plant and microbial nutrient demands.
• Ecosystem disturbance, like forest harvest, can disrupt N and P cycle synchronization through disproportionate nutrient loss.
• The stoichiometric balance of N:P is critical for nutrient cycling and ecosystem function.

Purpose of the Study:

• To model the resynchronization of nitrogen and phosphorus cycles following a northern hardwood forest harvest.
• To understand how nutrient loss and subsequent cycling dynamics affect ecosystem recovery.
• To identify factors limiting or enhancing the rate and extent of ecosystem recovery.

Main Methods:

• Simulation modeling of N and P cycles in a post-harvest northern hardwood forest.
• Analysis of nutrient loss during harvest and early succession.
• Tracking of N and P ratios in plant uptake, litterfall, and mineralization throughout succession.

Main Results:

• Harvest residue had a low N:P ratio, leading to preferential P release and N retention.
• Early succession saw excess P release, with P loss via mineral formation and leaching.
• Ecosystem recovery was limited by P availability, with alternating N and P limitation periods.

Conclusions:

• Ecosystem recovery from harvest is constrained by phosphorus availability and the resynchronization of N and P cycles.
• Preventing early P loss or enhancing later P supply are crucial for faster ecosystem recovery.
• Models of nutrient resynchronization are essential for assessing ecosystem disturbance and recovery dynamics.