24HRAS5

4. Moist, semi-decayed, organic matter.
6. Substances with a pH greater than 7.
9. Living in the presence of oxygen.
10. Measure of suspended sediments and nutrients in water.
11. Scale measuring acidity or alkalinity ranging from 0-14; 7 is neutral.
12. Downstream point where a river empties into another body of water.
13. Soils formed under saturated or inundated conditions supporting hydrophytic vegetation.
14. Irregular spots of different colors.
17. Species in danger of extinction.
19. Describing plants and soils existing in flooded, saturated, or ponded areas.
22. Measure of soil acidity or alkalinity expressed in pH values, ranging from ultra-acidic (<3.5) to strong alkaline (>9.1).
23. Diverse group of chlorophyll-containing, non-vascular plants in fresh or saltwater.

1. Surface layer (about 100 m deep) of the ocean that receives sunlight.
2. Depth zone in a water body where sunlight does not reach.
3. Organism living without oxygen.
5. Plants adapted to grow in water or wet soil conditions; singular plant is "hydrophyte."
7. Mass of plants covering an area.
8. Grass-like plants with triangular stems and inconspicuous flowers, typically growing in wet ground.
15. Ecosystem at the bottom of a lake.
16. Short plants with long narrow leaves and hollow jointed stems; flowers often inconspicuous and in clusters.
18. Temporary soil surface covering by flowing water from streams or runoff.
20. Animal and plant life of a region or period.
21. Animals killed and eaten by other animals.