IMCG: Lagow Meeting

Lagow Meeting Contribution

Revised INCOMPLETE DRAFT
Universal Mire Lexicon

Based on proposed new terms.

Ronald Hofstetter

Department of Biology, University of Miami,

Coral Gables, Florida, USA

Prepared for the IMCG Workshop,

Lagow, Poland, March, 2000

Objective

?Develop a LEXICON (set of terms and definitions) for global wet lands, about which there may be limited information, for conservation purposes.

Assumptions (worst case scenario)

Terminology will be

used throughout the world
for sites
known perhaps only from satellite imagery,
for which there is no "ground truthing",
for which no environmental conditions are known;
by individuals with no knowledge of or experience in interpreting wetlands or mires.

Basic Issues

Wet-land systems exist along a continuum between deep-water aquatic systems and terrestrial (upland) systems and wet lands have boundaries (limits) with aquatic and terrestrial systems that can NOT be objectively defined and identified.

Wet lands have

different origins and patterns of development (e.g., paludification, terrestrialization),
widely different geographical locations,
Different climates in which they develop,
Different sets of controlling forces,

different developmental status, such as

"mature" (in equilibrium with major existing conditions),
"immature" (in early stages of development - time issue),
"disturbed" (not in equilibrium with a controlling force that has been changed by humans),
"altered" (in equilibrium with a controlling force that has been changed by humans).

In spite of these differences, wet lands

are all directed in their development and controlled by one major factor - water,
have similar structural characteristics and
share many genera and species within comparable climatic regions throughout the world.

Current Problems

?Insufficient information about many global wet lands limits the determination of even minimal details about their character, specific controlling factors, developmental status or degree of disturbance.

The understanding, terminology and classification of mires
greatly exceeds that for other kinds of wet lands.
in Eurasia greatly exceeds that for wet lands elsewhere.

?Much confusion exists in the science and conservation of wet lands due to the lack of globally recognized terminology and classification schemes.

Conclusion

There is an immediate need for a unified global terminology of wet lands.

The ideal global terminology for wet lands should

NOT require prior knowledge of their specific details, but should enable the inclusion of this information as it becomes available without having to rename those wet lands and?
be capable of showing relationships of development, structure, function and shared controlling forces of the variety of global wet lands.

?No such scheme now exists and there are too many major problems in existing terminology to generate such a scheme using existing terminology.

Critical Differentiating Characteristics

?Prerequisite for development of a new terminology is the identification and prioritization of criteria on which to make decisions in successive levels of differentiation of types of wet lands and wet- land characteristics.

A consensus was reached at two previous IMCG workshops that

?1. "wetness",

?2. "the organic matter content of the sediment-sedentate" and

?3. "sedentate-producing vegetation"

?are the MINIMUM characteristics needed to define mire and basic types of mires.

Steiner and Succow previously concluded that the priority characteristics in differentiating kinds of mires are:

Source of water,
Prevailing hydrology-geomorphology,
Base content (saturation) or pH,
Nutrient availability and C:N, and
Prevailing plant communities.

?Mires are a subset of types of wet lands.

?Globally, there are many more kinds and more area of freshwater wet lands existing under a greater range and mix of controlling factors than there are for mires.

?The most important, universal criteria for defining freshwater "wet land" and delineating types of freshwater wet lands are

the time of year of saturation (by water) of surficial sediments and
duration of saturation (by water) of surficial sediments.

?There is NO universal, single priority in application of OTHER criteria for differentiating kinds of freshwater wet land.

?The following order of presentation of other controlling factors is NOT significant because their relative importance differs with kind of wet land and with location.

?Among the many other important factors used for differentiating kinds of wet lands are:

The amplitude and temporal pattern of variation in vertical difference between the water surface and sediment surface,
Chemical nature (e.g., pH, base content, nutrient content) of water entering the wet land. This is influenced by the duration and nature of the lithic materials with which the water has had contact and the chemistry of the atmosphere.
The pattern of movement of water through the wet land,
The physical and chemical properties of surficial sediments (e.g., porosity, permeability; content of clay, content and nature of organic matter; CEC, base saturation, pH, etc.)
Climate,
Vegetation on site.

NOTE: Information on Climate is generally available, vegetation can be determined partially by remote sensing and in more detail by ground truthing, sediments can be determined by on-site reconnaissance, BUT the other factors and more difficult to determine and are not likely to be available for all sites.

Criteria for NEW Terminology

There is a need for this term.
This the "best" term for the particular application.
The term must have no other usages.
The term shows the appropriate relationship (in its structure and controlling forces) to associated terms.
The term’s definition is clear and concise for current and future applications.
The term can be used in a consistent manner in many languages.

Proposed Terminology

Consider the following proposed terminology on the basis of the overall scheme, which uses terms that

have not been and are not being used in a different manner,
convey information about observable conditions,
are constructed to show relationships related to their patterns of development and controlling forces, and
may become more comprehensive as details become available.

Alternate roots and prefixes may be preferable to those proposed.

?The general term to include all those wet land sites (and conditions) that are neither aquatic nor terrestrial and which share the primary and many, if not most, of the other controlling factors is

????"Terrud"

[Derivation: "terrus" = earth, "udus" = damp, moist, wet]

?[Closest existing term, "wetland", Ramsar definition, extends more into deep-water conditions than does terrud.]

Proposed Definition

Terrud: "term applied to those communities and ecosystems

1) in which the presence of water in the uppermost edaphic/pedic layers is of sufficient duration to promote

a) anaerobic conditions long enough during the growing season to effect perennial selection of the dominant plants or animals and (or, in the absence significant biota)

?b) persistent anaerobic edaphic indicators, but

2) not consistently so deep as to exclude the establishment of potential, perennial, emergent macrophytes, and

3) that are transitional between terrestrial (upland) and aquatic communities and ecosystems."

?Fundamental (basic) kinds of terruds may be differentiated on the basis of general vegetation.

?Vegetation is commonly the most readily available and easiest to acquire useful information about a terrud or a possible terrud.

?Terms for the fundamental (basic) kinds of vegetation of terruds are:

?phytetic = characterized by vegetation

?aphytetic = not characterized by vegetation

?phytocryptic = hidden/unknown vegetation

?The characteristic plant communities of a phytetic terrud may be:

Graminetic = characterized by grass-like plants;

Herbetic = characterized by forbs, broad-leaved plants;

Arboretic = characterized by trees, forest;

Dumentetic = characterized by small trees and shrubs;

Bryophytetic = characterized by mosses;

Heterophytetic = characterized by other vegetation types;

Crasiphytetic = characterized by a mix of vegetation.

?A phytetic terrud may have two characteristic vegetative components, e.g.,

?Bryo-graminetic terrud = characterized primarily by graminoids and secondarily by mosses

?If the characteristic vegetation of a phytetic terrud is known, then the term for that vegetation replaces "phytetic" as a prefix. e.g.,

?Phytetic terrud becomes Graminetic terrud?

?Aphytetic terrud may consist of mostly exposed sediments or may be covered by water and so may be further identified as:

Limnetic = characterized by shallow, open water

Humetic = characterized by exposed sediment

?Again, the term for a known condition may replace the general term, e.g.,

Limnetic terrud replaces Aphytetic terrud if it is known to be covered by shallow water.

?A common fundamental controlling condition in terruds is the nature of the surficial sediment. The initial distinction is the amount and thickness of organic matter present.

?Organic matter isolates plant roots from the underlying lithic materials and affects redox potentials, nutrient availability and critical hydrologic parameters.

?Proposed terms for the kinds of surficial sediments are:

lithopedic terrud = mineral-rich sediment

organopedic terrud = organic-rich sediment

arcanopedic terrud = unknown sediment

Derivation: ?"pedon" = ground, earth, soil;

???"arcan" = secret, unknown

?Each of these kinds of sediments can be further differentiated, e.g. lithopedic terrud (mineral-rich sediment) include

Micropedic = predominantly fine sediments

Silicapedic = predominantly sandy sediments

Chalicopedic = predominantly coarse sediments

Calcipedic = predominantly calcareous matter

Eulithopedic = predominantly massive rock

?Each of these proposed terms for the kinds of surficial sediments can be further differentiated, e.g., for organopedic (organic-rich sediment) there is

Amorphorganopedic = amorphous organic matter

Graminopedic = graminoid-based organic matter

Bryopedic = bryophyte-based organic matter

Arbopedic = woody organic matter

Mixorganopedic = organic matter of mixed materials

?When the type of sediment is known, the more specific term may be used as a replacement for the more general, e.g.,

?Organopedic terrud (organic-rich sediment) may be called Graminopedic terrud if it is known that the organic matter is derived primarily from graminoid remains.

?The source of material and the manner in which they enter the surficial pedic deposits may differ and need to be identified as:

allo- = allochthonous: carried in from outside the immediate area, then deposited;

auto- = autochthonous, sedimentary: derived from accumulated litter produced on site;

insito- autochthonous, sedentary: derived from vegetative materials deposited in situ

arcano- = unknown

?"Source qualifiers" for surficial pedic deposits are incorporated as a prefix, e.g.,

?insito-bryopedic has in situ - produced (autochthonous), sedentary materials derived primarily from mosses.

?If the moss is known to be Sphagnum, the pedic term could be further differentiated as ?insito-sphagnopedic

?In existing terminology this example is a "mire", it may be a "bog", and the pedic material is sphagnum "peat".

?Conditions on a terrud may be further differentiated on the basis of the combined presence/absence of

?1) vegetation promoting the accumulation of organic sediments and

?2) abiotic conditions that promote the preservation of organic-rich surficial deposits

Terms have not yet been determined for these parameters, but their relationship is shown in the following tables. [NOT included here]

?Another factor important in differentiating types of terruds is the source of near-surface water. Here these are:

?chthoniohydric - water from the earth (= geogenous, minerogenous)

?aeriohydric - water from the atmosphere (= ombrogenous)

?Many other differentiating or qualifying properties of various kinds of terruds may be incorporated using this approach, but as they are added, the term may become excessively long. e.g.,

aeriohydric sphagnophytic insito-sphagnopedic terrud

?Many other differentiating or qualifying properties of various kinds of terruds may be incorporated using this approach, but as they are added, the term may become excessively long. e.g., aeriohydric sphagnophytic insito-sphagnopedic terrud

(= bog to some, but not all, people)

?Another factor important in differentiating types of terruds is the manner of movement of near-surface water:

Atransfluo?= lacking (or very little) horizontal flow

Minortransfluo =slow horizontal "sheet flow"

Mesotransfluo= moderately, horizontal "sheet flow"

Fluviotransfluo= moderate, horizontal channelized flow

Anomotransfluo =variable speed, horizontal flow

Dubiotransfluo = unknown horizontal flow

?[hyper- or super- = above, over surface;

?intro- or infra- = within sediment]

?Another factor important in differentiating types of terruds is the nutrient availability of near-surface water and deposits. This may be included as

?hypotrophic = containing small amounts of ?????available nutrients

?mesotrophic = containing moderate amounts of ????available nutrients

?hypertrophic = containing excessive amounts of ????available nutrients

?Proposed Terminology

?How are these "descriptors" identifying the characteristics of terruds arranged in this proposed new terminology?

?Generally, according to one’s interests. e.g.,

If one is interested primarily in peat, only the relevant descriptors need be included.
If one is describing a terrud in detail, the descriptors may be arranged in decreasing order of importance for particular emphasis.

Conclusions

This proposed new terminology provides

a logical basis for the differentiation of the general types of global terruds using informative prefixes that identify the character of each controlling factor,
an open-ended structure to include additional descriptors as needed,
a framework to include as many characteristics of a terrud as desired,
a hierarchical system of unique terms that show relationships among general types of global terruds.

Conclusions

Also, this proposed new terminology

avoids confusion with existing terminologies by using a unique structure and avoiding the use of existing terms,
produces detailed, informative, composite terms for sites that can be related to sites identified by existing terms,
Is the only existing terminology system capable of providing a name for the great diversity of global mires and "wetlands".

Conclusions

What are the limitations or problems with this proposed new terminology?

It is incomplete and still evolving,
Perhaps better descriptors could be found,
It is new and different from what everyone has been using until now.
It is cumbersome, creating a long term for a site, especially if all the descriptors are used.

?(It is more informative and less awkward than the current US system of wetland terminology.)

Conclusions

?What role, if any, can this proposed new terminology play in mire science?

?It is not likely to replace existing terminologies for the reasons listed above.

?It can be very useful as a universal short-hand "definition" for existing terms so as to show similarities and differences among those terms, thereby clarifying existing terms.

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