A conservation biologist studies a watershed where rainfall collection feeds into community water systems. Last year, 1,500 mm of rain fell. This year, due to reforestation, runoff efficiency increased by 25%, but total rainfall decreased by 10%. What is the effective runoff volume this year in mm, assuming last years runoff was 600 mm?

Tue, 05 May 2026 23:29:51 +0000

**How Efficiency and Rainfall Shape Watershed Balance — A Conservation Biologist’s Insight** What if a community’s water supply depends not just on how much rain falls—but on how much of that rain actually flows into streams and reservoirs? For conservation biologists studying watersheds, this quiet interplay between rainfall, reforestation, and runoff efficiency reveals a dynamic story of environmental resilience. Last year, a region recorded 1,500 mm of rain. This year, thanks to targeted reforestation, rainfall efficiency rose by 25%, yet total rainfall dropped by 10%. Amid this shift, a key question emerges: What is the effective runoff volume feeding local water systems? ### Why This Matters — Hydrology in a Changing Climate In the U.S., communities increasingly rely on natural watersheds as their primary source of clean water. Conservation biologists track these systems to balance environmental health with human needs. This year’s scenario—higher efficiency even with less rain—highlights how reforestation transforms rainfall into usable runoff. The biologist’s role isn’t just monitoring: it’s understanding how ecosystems adapt, ensuring reliable water supplies even amid climate variability. With more rain efficiently channeled into runoff, reservoirs and aquifers recharge more effectively, supporting both people and natural habitats.