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Disturbance Mediated Changes in Litter Turnover and Nutrient Use Efficiency Facilitate Vegetation Shifts in Tropical Dry Ecosystems: Insights From a 10-Year Vegetation Management Study
| First Author: |
Chaturvedi, R. K. |
| Abstract: |
Tropical dry forests and savannas are critical yet understudied ecosystems that regulate global biogeochemical cycles and support biodiversity. However, their functioning is increasingly threatened by anthropogenic disturbances and climate change. Here, we present a decade-long study (2005-2014) examining litterfall dynamics and nutrient cycling across protection gradients (permanently protected [PP], moderately protected [MP], and unprotected [UP] stands) in India's Vindhyan plateau, where forests are transitioning to savannas due to land-use change. Using field measurements, satellite data, and ecological modeling, we quantified how protection status mediates ecosystem processes in these contrasting biomes. We found that protection status overrides biome differences in driving ecosystem function. PP stands maintained 35%-50% higher annual litterfall (6.4 vs. 3.2 Mg ha-1 yr-1) and double the nutrient return rates (2.54 vs. 1.19 Mg ha-1 yr-1) compared to UP stands, facilitated by microclimatic buffering (3 degrees C-5 degrees C cooler soils, 15%-20% higher humidity) and reduced disturbance. Forests exhibited elastic resilience, resisting degradation until abrupt collapse under high disturbance, whereas savannas showed graded resilience, declining linearly with disturbance intensity. Alarmingly, MP stands displayed limited recovery, suggesting passive protection alone is insufficient for restoration. Disturbances disrupted nutrient cycling, with UP areas showing 20%-25% higher nutrient use efficiency (NUE)-a short-term survival strategy that reduces long-term nutrient availability. Savanna UP sites are projected to lose 30%-40% of litterfall capacity by 2035, risking irreversible degradation. Landsat data revealed a 6.3% decline in forest cover (2002-2014), exacerbating fire-prone feedback loops. Our findings underscore that protection is paramount for maintaining tropical dry ecosystem functions. Forests require fire suppression, while savannas need grazing management. We advocate for landscape-scale conservation integrating protected cores with buffered use zones. This study provides a framework for managing biome-specific resilience in the face of global change, emphasizing urgent, targeted interventions to avert ecosystem collapse. |
| Contact the author: |
Chaturvedi, RK |
| Page Number: |
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| Subject: |
Environmental Sciences; Soil Science |
| Impact Factor: |
3.7 |
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| PubYear: |
2025 |
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| Publication Name: |
LAND DEGRADATION & DEVELOPMENT |
| The full text link: |
10.1002/ldr.70334 |
| ISSN: |
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| Download: |
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