The surrounding land area that
drains into a lake, river or river
system.

A lowland area, such as a marsh or
swamp, saturated with water.
Wetlands are crucial wildlife
habitat, and important for flood
control and maintaining the health
of surrounding ecosystems.

Microscopic animals.

Alkalinity is measured in mg/l as
calcium carbonate (CaCO3). It
represents a measure of a
solution's ability to buffer or
neutralize acids. Lakes located in
areas of
calcareous glacial till (common
throughout central and southern
Minnesota) will have higher
alkalinity than lakes formed on
non-calcareous bedrock (common in
northeastern Minnesota). Water with
alkalinity less than about 75 mg/L
could be considered soft, 76-150
moderately hard, 151-300 hard, and
greater than 300 very

A very nutrient-rich lake characterized by frequent and severe
nuisance algal blooms and low transparency.

The river than surrounding land drains to. Minnesota is
characterized by nine major River Basins.<BR>
<UL>
<LI>UMB = Upper Mississippi
<LI>LMB = Lower Mississippi
<LI>MNB = Minnesota River
<LI>RRB = Red River
<LI>RAB = Rainy River
<LI>LSB = Lake Superior
<LI>CDB = Cedar and Des Moines
<LI>MOB = Missouri
<LI>SCB = St. Croix
</UL>

Measured against a platinum-cobalt standard (PCU or Pt-Co units),
can give an indication of the relative amount of dissolved
organic matter in the water. High coloration, or "bog stain" as
it is referred to, is usually caused by runoff from wetlands or
forested lands. At high values, color may interfere with the
expected phosphorus - chlorophyll - Secchi relationship of a
lake. In general, values between 0-20 are considered clear, 21-50
are considered moderately colored, 51-100 are considered

The 8-character federal code identifying the Cataloguing Unit,
the smallest of the different hydrologic units. The coding is
hierarchical with a 2-character region, a 4-character subregion,
a 6-character accounting unit and an 8-character cataloguing
unit.

All trophic status rankings are conducted by ecoregion and
expressed as a percentile. In general, as trophic state
increases, moving from oligotrophy to eutrophy
(e.g., phosphorus and chlorophyll increase and Secchi
transparency decreases), percentile ranking decreases.

FS=Full Support<br>
MS=Full Support(marginal)<br>
PS=Partial-Support<br>
NS=Non-Support