water from top to bottom. They also get considerable light penetration . However, there are great seasonal changes in wind , temperature, evaporation , and precipitation in ponds versus lakes. -Citations http://en.wikipedia.org/wiki/Lentic_ecosystem http://apbiology.ygoy.com/201/what-is-meant-by-lentic-ecosystem/ http://www.kidcyber.com.au/topics/biomewater.htmhttp://energytechstocks.com/wp/wp-content/uploads/2008/09/pond-scum330.jpghttp://www.colorado.edu/geography/class_homepages/geog_3251_sum08/05_crater_lake_caldera.jpg Javascript Required You need to enable Javascript in your browser to edit pages. help on how to