Analysis of Vegetation Coverage at New Brittany Phase I Wetland to Determine if it Meets the Corps Requirement in the 7th Growing Season

Justin Smith, Department of Biology, York College

Introduction

Wetlands contain a high degree of biodiversity, provide shelter, food, fiber, and also help stabilize shorelines, filter water, control erosion and act as flood storage (Balzano and others 2002) (Tiner R.W. 1999).

In 1972 the Federal Clean Water Act was created. Section 404 of the Act is administered by the U.S. Army Corps of Engineers (Corps). The Corps requires compensation, in the form of mitigation, for impacted wetlands. The mitigated wetlands must then be monitored for 5 to 10 years to be considered a success. If within the specified time the wetland becomes dissatisfactory a remedy must be performed (Morgan K.L. & Thomas R.H. 1999).

I conducted this research because the mitigated wetland that LSC design Inc.1 was monitoring for its 5th final year failed to meet the Corps permit requirement for a minimum vegetation coverage of 85% FAC, FACW or OBL native species, (see footnote^ in Table 1. for definitions). On the other hand the wetland did meet the requirements for a minimum of five dominate wetland species. A reason the wetland might not have reached it’s requirement was because a large part of the lower section of the wetland turned into a pond, so LSC decided to lower the water level in hopes that the wetland would support more vegetation.

Objective

The objective of this study is to reevaluate the wetland in its 7th growing season, after the water level was lowered, and determine if it now meets the Corps requirement. The Corps require 85% vegetation coverage, and a minimum of 5 dominant wetland species. All dominant wetland species should total more than 50% FACW or OBL.1LSC design of York. Pa was responsible for the mitigation

Before After

Materials/Methods

Five pre-established transects were analyzed. Within each transect were sample points approximately 18ft. apart. A total of 17 sample points were evaluated using a square meter. Within each square meter a visual inspection was performed to identify species, and estimate percent aerial vegetation coverage for each species. Species were assigned to a wetland indicator status. For each plot, the aerial coverage was summed for all species within an indicator status.

Results

Table1. 5th Growing Season 7th Growing Season

Vegetation-mean % aerial coverage

OBL ^ 48*s.d.-29 77 s.d.-26

FACW+ 11 s.d.-14 11 s.d.-13

FACW 18 s.d.-25 20 s.d.-24

FAC 0 0

FACU 0 0

Total % 77 108

# Species 12 12

Discussion

Review of the results reveal that the vegetation coverage in the 7th growing season is above the 85% needed for the 5th growing season permit requirement. The 7th growing season contains an average % total of 108, all of which were OBL, FACW+, or FACW. The 7th growing season also meets the requirement for containing at least 5 dominant wetland species, which totaled more than 50% FACW or OBL.

Literature Cited

Balzano and others. 2002. Creating Indicators of Wetland Status (Quantity and Quality): Freshwater Wetland Mitigation in New Jersey. Division of Science, Research and Technology. Trenton, New Jersey

Morgan K.L. and Thomas R.H. 1999. An Assessment of Wetland Mitigation in Tennessee. Published by Tennessee Department of Environment and Conservation. Nashville, Tennessee

Tiner R.W. 1999. Wetland Indicators A Guide to Wetland Identification, Delineation, Classification, and Mapping. Lewis Publishers. Boca Raton, Fl

Acknowledgements

Great thanks to my mentor Bruce Smith of York College and Tom Stich of LSC design for there time and wisdom in helping me prepare and complete this project.

*Vegetation mean percent s.d. (N=17)

^Species indicator status- percent of observations that the species is found in wetlands- OBL (99%), FACW+ ( 66-99%), FACW (66%), FAC (33-66%), FACU (1-33%)

s.d.-standard deviation

T5T4 T3

T2 T1

T= Transect

= Sample point

Sources of hydrology- subsurface water table, surface runoff, and floodwaters.

Wetland diagram

Species mean aerial coverage 5th year % 7th Year %

American burreed (Sparganium americanum), OBL 0 37

Duckweed (Lemna sp), OBL 21 30

Grass, FACW 0 17

Cattail (Typha latifolia ), OBL 18 10

Jewelweed (Impatiens capensis), FACW + 3 8

Blue vervain (Verbena hastate), FACW 3 3

Pa smartweed (Polygonum pensylvanicum), FACW+ 0 2

Boneset (Eupatorium perfoliatum), FACW+ 2 .6

Soft rush (Juncus effusus ), FACW 9 .3

Mild water-pepper (Polygonum hydropiperoides ), FACW+ 0 .3

Polygonum FACW 0 .1

Tearthumb (Polygonum sagittatum ), FACW 0 .1

Canary grass (Phalaris arundinacea ), FACW 6 0

Black willow (Salix nigra ), FACW+ 5 0

Duckweed minor (Lemna minor ), OBL 5 0

Purple willow-herb (Epilobium coloratum ), OBL 2 0

hallow sedge (Carex lurida), OBL 2 0

Barn yard grass (Echinochloa muricata ), FACW+ 1 0

Total % 77 108.4

Table 2.