Geoscience Reference
In-Depth Information
whether they are from federal, state, local
government, non-proi t or private sources is
undertaken at this stage.
•
Management practices
- Based on the
overall objectives as well as the inventory,
valuation and budgeting steps completed
earlier, the management plan selects the
most appropriate combination of practices
to implement at the project site. A review of
some of these practices is provided starting
in the next section of this chapter.
•
Monitoring and evaluation
- Implemented
management strategies need to be moni-
tored and periodically evaluated for their
effectiveness in meeting stated goals. Adjust-
ments to plan components may become nec-
essary as new issues emerge or unexpected
problems are encountered.
Table 12-1.
Wetland management strategies and
practices.
Terrestrial &
Hydrologic
Biological &
Chemical
Socio-economic
• Ditching
• Dredging &
channeling
• Agricultural
tiling
• Vegetative
buffering
• Water level
manipulation
• Vegetation
manipulation
• Terrestrial
modifi cations
• Prescribed
burning
• Mowing.
disking,
plowing
• Grazing
• Stocking
• Propagation
• Species
introductions
• Chemical
applications
• Moral suasion
• Mutual
enforcement
• Incentive and
disincentive
mechanisms
• Taxes, fees,
subsidies,
tradable
credits, bonds,
covenants,
easements,
transfer of
development
rights
• Stakeholder
incentives
• Green labeling
& certifi cation
12.4 Wetland management practices
The resource management practice used at a
particular site would depend on what type of
wetland is being managed and for what specii c
purpose. Management practices vary depending
on whether one is working in a riparian wetland,
peatland, coral reef, or salt marsh, and would
be conditional upon whether the wetland is
being managed for bird habitat, to provide a
source of fresh water and sustenance to a local
community, or to enable transportation and
navigation. In each of these cases, the manage-
ment strategies involved would be somewhat
different. Yet, in each case, a wetland manager
must be mindful of the impacts that different
strategies could have on other components of
the wetland ecosystem and its dependent human
community.
Wetland management strategies are generally
based on current scientii c assessments and the
collective wisdom of successfully implemented
past strategies. However, improvements in tech-
nology and advances in the knowledge of wetland
functioning require a regular re-assessment and
i ne-tuning of strategies used. A survey of past
and current terrestrial-hydrologic, biochemical,
and socio-economic strategies to manage wet-
lands is provided in Table 12-1.
12.4.1 Terrestrial and hydrologic-based
strategies
Terrestrial modii cations to maintain wetland
habitats or alter them into other land uses
have included ditching, dredging, i lling, levee
construction, agricultural i eld tiling, and
impoundment works. Depending on the extent
of modii cations undertaken, these may pre-
serve basic ecosystem processes
-
allowing the
wetland to sustain itself
-
or alter the hydrologi-
cal regime of a wetland, cause unnatural water
l uctuations and l ows, and destroy its ecological
balance. Modii ed wetland ecosystems have sus-
tained human populations for centuries and
today one would be hard-pressed to i nd wetland
sites entirely free of human inl uence. Some of
the commonly observed methods to manage
wetlands are elaborated below.
Ditching involves the construction of chan-
nels through marshes and peatlands with the
aim of draining pool and pond features and
controlling the accumulation of surface water
(Resh 2001). Historically, this process was carried
out to aid land-use conversions and control
mosquito populations. Along the northeastern
