Eco-Station 1: Begin Virtual Greenway Tour and Project Description

Summary Statement: Located in Oneonta, New York, New Island offers a unique opportunity for public environmental awareness and for student participation in ecotourism and ecological planning. Through the New Island Environmental Education and Greenway Development Project, funded by the Environmental Protection Agency, environmental science students are studying the ecosystem of one section of the Susquehanna River riparian zone. Project results will aid in the potential construction of a multiuse nature trail in an environmentally sensitive park.
Project Study Site: New Island is unusual in that it is an area of longstanding biological productivity and diversity, despite being adjacent to a heavily developed river lowland and city. New Island is located along the banks of the Susquehanna River within the city limits of Oneonta, New York. It is an 100-acre riparian lowland located in the floodplain of the Susquehanna River. Officially, 82-acres (33-hectares) of New Island is designated as a park, although no city park facilities exist.
Methodology/Results: Fifteen way-stations/observation points, referred to as Eco-stations, were “virtually” established to explain various ecosystems and ecologically significant habitats. The Eco-stations exhibit and interpret ecological features to students and the general public via a virtual eco-tour uploaded to the World Wide Web. A hypothetical trail connects each Eco-station, creating a virtual circuit that reduces the environmental impact of the trail system, while maximizing connectivity.

Eco-Station 2: Southside Dam - New Island Dam Ecology

Southside Dam directly impacts New Island ecology and geomorphology. The Dam is located along the east entryway to New Island. Southside Dam was built in 1908 on the Susquehanna River at Oneonta. The Oneonta Milling Company built it; however, today the Dam’s main purpose is minor flood control.

The Dam’s major influences on New Island’s ecology are numerous.

1. Flood Reduction and Emergents - High frequency, annual minor floods, and occasional large floods, on the order of 10 year or greater recurrence intervals, effectively reset vegetative succession. Emergent wetlands within the flood inundation zone are restored by floodwaters. Southside Dam reduces the frequency of small to moderate floods, thereby preventing the establishment and reestablishment of emergent wetlands except in those areas from next to the river’s edge to the second historic flood terrace.
2. Forested Wetlands - In the absence or minimization of flooding, later-stage successional wetlands are established over time. Consequently, most of the land area on New Island not impacted by recent human activities (farming, grazing, and settlement) are forested wetlands. Historically, the habitats close to the river would have consisted of scrub/shrub woody species giving way to emergents near a water source. Surface water and terrestrial environments are partially uncoupled.
3. Sedimentation - Southside Dam blocks the flow sediments and allows for upstream accretion. Further, it impacts the geomorphology by altering the natural patterns of water and energy flow.

Click here for a student project on dams at New Island.

Eco-Station 3: New Island Landuse/Landcover: A Landscape in Transition

Island Formation and Perturbations- New Island offers unique environmental opportunities for students and citizens of the Oneonta region. Its rich history weaves a mosaic of both human and ecosystem tenacity. Once a site of longstanding biological productivity and diversity, it was briefly interrupted by human settlement, industrial activity, and railroad development. In fact, New Island is not a natural island at all. It was created. Pre-human intervention, New Island was a part of the Susquehanna’s active channel that linked the northern floodplain to the adjacent uplands. New Island emerged as an island only during periods of excessive flooding. Otherwise, it formed the left bank of the river and was stabilized by natural terraces. New Island was not created until flow from the Susquehanna River was partially diverted by the Upper River Dam and impounded to form Electric Lake.

The city of Oneonta demanded electrical power; thus, the Island was created when the Electric Water Company of Oneonta built a 178-foot long diversion dam. Water was diverted around the island and was impounded down stream from the diversion behind a five-foot high, 55-foot long dam and powerhouse. Click the photo above to view maps that illustrate the impoundment and the creation of New Island. The dam was later acquired and operated by New York State Electric and Gas until it was razed in 1970. Consequently, the Island is no longer an island. Natural conditions, while impeded by Interstate 88 to the north, have returned.

Oneonta was a railroad town marked by several railroad tracks passing through the city limits. Historically, railroad tracks bisected New Island in an east-west direction. A switching-yard occupied the center of the Island. The New York Central Railroad Company sold the property to the Delaware and Otsego Railroad Company. After falling into disuse by 1970, the railroad property was acquired by the State of New York for the construction of I-88. In 1983 the state sold the land to the city for a waived sum of $1.00. Nature trail development and other environmental activities are in line with the stipulations of the land grant. The grant requires that the lands granted in the transaction shall be properly improved, maintained, and continuously used for park purposes or the land will revert to the State of New York.

Over the past 30 years the park has seen few visitors and experienced little interaction with its adjacent urban land uses. It has recovered remarkably from past industrial perturbations. Today the park emanates a strong since of naturalness.

Eco-Station 4: Electric Lake and Hydroseral Succession

The Island was created when the Oneonta Electric Water Company built a diversion dam to impound water downstream behind a powerhouse. In 1898, the locally-owned Company bought 50 acres of land at East End (now New Island), constructed a dam and hydroelectric powerhouse, and then built a bulkhead across the Susquehanna River (former Oneonta Upper River Dam) to divert water into newly formed Electric Lake. For many years the powerhouse provided all of Oneonta with electricity.

Hydroseral succession is a natural, but often human accelerated process of "terrestrialization". Lakes and wetland depressions progressively fill with sediments and become dryer terrestrial environments. Vegetation may change from hydrophytic wetland species to upland species. By removing the dam and diversion gates Electric Lake no longer had an inflow of water. Over time, standing water was replaced with sediments as the basin in-filled. Without a stream-flow sources, Lake water evaporated and percolated to groundwater and vegetation type progressively adjusted to dryer conditions.

Eco-Station 5: Railroad Bed, Hydrology, and Trail Development

City Park - Oneonta was a railroad town marked by several railroad tracks passing through the city limits. Historically, railroad tracks bisected New Island in an east-west direction. A switching-yard occupied the center of the Island. The New York Central Railroad Company sold the property to the Delaware and Otsego Railroad Company. After falling into disuse by 1970, the railroad property was acquired by the State of New York for the construction of I-88. In 1983, the state sold the land to the city for a waived sum of $1.00. Nature trail development and other environmental activities are in line with the stipulations of the land grant. The grant requires that the lands granted in the transaction shall be properly improved, maintained, and continuously used for park purposes or the land will revert to the State of New York.

Mainstem Trail - Because the railroad bed remains today, it will become the heart of the greenway trail system on New Island. The bed provides an ideal path, as it is elevated and very little vegetation grows upon it. Other than grasses, most vegetation finds the bed inhospitable, due to low nutrient content levels found in the gravel/slag fill material.

Hydrologic Connectivity- The natural flow surface and groundwater is disrupted by the elevated landfill that once marked the old railroad bed. The bed acts as a dike that impedes hydrologic connectivity between the land and river. Consequently, north of the railroad the land is dryer and vegetation composition is remarkably different from the hydrophytic vegetation found south of the bed. In general, riparian forest gives way to woody shrubs, vines, and herbaceous thorny plants.

Eco-Station 6: Wetland Soil Analysis

Hydric is defined by the Natural Resources Conservation Service as “soils that are formed under conditions of saturation, flooding, or ponding long enough to develop anaerobic conditions in the upper part”. Hydric means “wet”, so hydric soil means “wet soil characteristics”.

Eco-Station 7: Water Quality Analysis

Overall water quality analysis on New Island and in the adjacent Susquehanna River reveals promising results. A number of water quality parameters were measured and, over all, the water health is good. Point source pollution from parking lot runoff and localized elevated chloride levels offer minor concerns.

Click on the Eco-Station 7 link for a full report on water quality.

The following table provides a list of averaged water quality values for New Island.

Eco-Station 8: Tree Identification and Distribution

New Island has a wealth of natural resources ready for exploration. From the water's edge inland, the Island is covered with a rich array of landform types, plant species and animal species. Box elder, silver maple, red maple, ash elm, willow, oak, and sycamore are the dominant trees species. Speckled alder, scrub willow, dogwood, and viburnum are the dominant shrubs species. The Island has many ecosystems, from lowland emergent wetlands to upland palustrine wetlands and from patches of grassland to stands of forest. A large healthy riparian forest system is located on the Island. Such forests are unusual in an urbanized area because of the intense competition for landuse near the river; yet, they are critical to a functioning riparian zone

The purpose of this study is to determine the identification, frequency, and distribution of dominant tree species within the New Island riparian zone. Click Here to View Tree Identification and Distribution Study

Eco-Station 9: Riparian Wetlands

What is a Wetland? To be officially classified as a wetland according to the United States Fish and Wildlife Service, wetlands must have the following attributes: (1) at least periodically, the land supports predominantly hydrophytes; (2) the substrate is predominantly undrained hydric soil; and/or (3) the substrate is non-soil and is saturated with water or covered by shallow water at some time during the growing season of each year.

Wetland Types - Basic wetland types common to the New Island riparian zone are: emergent riparian wetlands, forested riparian wetlands, palustrine riparian wetlands, and lacustrine wetlands. Each of these wetland types is strongly influenced by the hydrologic connectivity provided by the Susquehanna River as surface, hyporheic, or groundwater flow.

Common Wetland Vegetation - By far, the single largest wetland type and landcover on the Island is forested riparian wetlands. Riparian forest occupies moist areas adjacent to a river and situated within the floodplain. Annual flooding is common and necessary to a healthy riparian forest. Typically the transition between riparian and upland forest is not sharp; rather upland trees will typically invade lowland areas. Silver and Red Maple are widespread throughout New Island and its adjacent uplands. Tree species common to the forested riparian area on New Island are American Elm, American Hornbeam (Iron Wood), Eastern Sycamore, Red Maple, Silver Maple, and Black Cherry. Spice Bush, Bottombush, and River Grape are widespread shrubs. Common herbaceous species are Skunk Cabbage, Golden Rod, Jack-in-the-Pulpit (Indian Turnip), Cinnamon Fern, and Stinging Nettle.

Eco-Station 10: Exotic Hydrophytic Species on New Island

Purple Loosestrife and Japanese Knotweed - What are exotic plant species? Exotic plant species are invasive super weeds. They are plants not native to a given area that can out-compete and displace native species, thereby altering ecosystems. Worldwide, invasive species are considered to be the second leading cause of species extinction and endangerment. (Habitat loss and fragmentation is number one.) According to the Congressional Office of Technology Assessment, invasive species also negatively impact agriculture, industry, and human health. Exotic species cause one billion dollars of documented damage per year in the United States. Two exotic species found on New Island are practically troublesome: Purple loosestrife and Japanese knotweed.

Monotypic - In spite of its impressive beauty, purple loosestrife is a particularly wearisome plant to natural ecosystems. It forms monotypic stands in wetlands that nearly eliminate native vegetation and greatly reduce habitat for other vegetation, fish, birds, and insects. Until recently, effective control methods have been non-existent; however, research on biocontrol insects has shown promise.

Vegetative Reproduction - apanese knotweed is widespread on New Island. It is an upright, fast growing herbaceous perennial that may grow 10 to 15 feet in height. Japanese knotweed spreads rapidly to form dense monotypic thickets that out-compete native vegetation and degrade the natural ecosystems. It practically threatens riparian areas, where it can survive significant flooding and longstanding soil saturation. Floodwaters uproot and break rhizomes allowing for rapid and extensive vegetative reproduction along scoured shores and islands. Once established, stands are exceptionally persistent and difficult to eradicate. Efforts to dig and remove selected knotweed populations on New Island have been unsuccessful.

Click here for a student project on Exotic Species on New Island.

Eco-Station 11: New Island Soil Chemistry Analysis

pH and Macronutrient Overview - The average pH of the soil on the island is approximately 6.2, with variation from 5.8 to 6.4. The slightly acidic pH values are expected, considering numerous stands of coniferous forest cover in the area and somewhat low pH of regional precipitation. Needles that fall from coniferous trees decompose and contribute to soil acidity. The pH of the soil is not too acidic to prevent a high degree of plant biodiversity. To view a graph of pH click here.

Macronutrients (nitrogen, phosphorus, and potassium) are the main nutrients that plants need for healthy growth. According to the results of the soil analysis, there are ample macronutrients for healthy vegetation. Click here for graph of macronutrients. The average concentration of nitrogen is 30ppm, varying from 81 to 11. Sample 2 reveals higher concentrations at 81ppm and samples 4,8, and 11 has significantly lower concentrations at 11 ppm. Average phosphorus on the island is 22ppm, with most of the area sampled having 12.5ppm. Sample #10 had the most at 50ppm. 60ppm was the average potassium on the island. The highest was 90ppm from sample #10. Most of the samples had 50ppm.

Eco-Station 12: New Island Turbidity Analysis

Turbidity Defined - Turbidity is a unit of measurement that quantifies the degree of scattered light traveling through a water column. Light is scattered by suspended inorganic and organic particles such as clay and algae. As the suspended load in a water column increases, light is increasingly scattered. Turbidity is measured in Jackson Turbity Units (JTU’s) by comparing the suspended solids of a measured amount of a sample with an identical amount of turbidity-free water. Zero JTU’s represents no turbity, while a sample of 100 JTU’s indicates extremely turbid water.

Results - Samples taken from the Susquehanna River adjacent to New Island reveal low to moderate turbity levels. On average, samples ranged from 5 to 8 JTU’s. For the Upper Susquehanna River, turbidity between 0 and 5 JTU’s indicates low turbidity and good water quality. Turbity measured between 6 and 50 JTU’s signifies moderate levels of suspended solids and fair water quality. Anthropogenic sources of elevated turbidity are a concern for the Upper Susquehanna River. Following a typical summer thunderstorm, turbidity measurements were recorded as high as 50 JTU’s. Solids carried by runoff from development and farming in the watershed are high during and following precipitation events or snowmelt. Major potential impacts of increased and sustained turbidity levels may include greater possibility for waterborne disease by harboring micro organisms and altering the composition of the aquatic community by reducing light penetration.

Major causes of anthropogenic turbidity acceleration to the Upper Susquehanna River are:
1. Destruction of riparian vegetation buffers along waterways
2. Inorganic runoff from agricultural fields through erosion
3. Construction sites and urban development
4. Nutrient runoff from agricultural fields inducing algal growth

Future monitoring of turbidity at New Island will be conducted using a digit turbidity meter measuring suspended solids in Nephelometric Turbidity Units (NTU’s). Turbidity measured in NTU’s provides more precise date.

Eco-Station 13: Oneonta Upper River Dam Removal

Ecological Island - The Oneonta Upper River Dam was removed in 1958 following the 1954 close of the New York State Electric and Gas Company plant operation on Electric Lake, Oneonta. The river closely resumed its historic course of pre-1898. In 1898, the river was diverted by the Upper River Dam to form Electric Lake and, subsequently, New Island. Today New Island is no longer an “island” in the conventional manner of being surrounded by water on all sides. However, it remains a natural ecological island encompassed by regional development.

Hydroseral Succession - Despite the removal of the Dam and the diversion gates, minor high water surface flow and considerable groundwater hyporheic flow continue to course through the old waterway. Such hydrologic connectivity to the terrestrial environment allows for riparian wetland species to flourish further from the mainstream. Also, the dike around historic Electric Lake, channelizing diversion river flow, was not removed. Water tends to pond in places during wetter periods, forming lacustrine wetlands. The slow progress of sediment accretion and hydroseral succession is evident in the lacustrine depressions.

Eco-Station 14: White Tail Deer Population

"Overpopulation" Species Density and Carrying Capacity - Observation of deer populations on New Island suggest that deer per unit area of habitat is high. Deer are more concentrated in the northeastern section of New Island where former farmland offers good grazing. Deer easily leave New Island for other locations within the City. The only real barriers are roads, which deer seem to navigate as well as students at a crosswalk. Observations that suggest "overpopulation" come as no surprise for Oneontans. Deer graze highly palatable young flower shoots and garden delicacies. During the spring and summer, a good meal of exotic plants is not hard to come by. Because winter conditions are harder for deer in Oneonta, they often graze unprotected ornamentals. Some would contend that deer in Oneonta have reached the level of pest.

To answer the question "are deer populations in Oneonta at levels consistent with overpopulation" requires the analysis of many complex variables. By eliminating the natural predators of deer, basic plant-herbivore relations are upset. An increase in deer population equates to an increase in grazing. As overgrazing ensues, deer starve and die. Deer populations grow larger than the environment's physical carrying capacity can support, resulting in a die-off or crash. Ironically, humans come to the rescue. Fields are cleared of timber and homeowners design immaculate grass lawns. Available food supply increases significantly in and around the City, and deer populations surge..

Environmental Resistance Factors - Carrying capacity should only be used as a basic frame of reference when considering "overpopulation". There are too many variables that determine actual capacity. In response to the question of deer overpopulation - yes, deer overpopulation exists if this were a natural system. Because humans have reduced the number of environmental resistance factors in the Oneonta area, deer carrying capacity has unnaturally increased. The City can support a large healthy deer population.

The arithmetic density of deer on New Island is between 9 and 28 deer per square mile. This is not an exact arithmetic density count. And new studies will be conducted. The basic methodology entails counting the number of deer pellet groups along a transect. The average deer defecates 13 times per day. Essentially by determining the number of pellet groups found over a known area and given length of time, reasonable deer population estimates can be determined.

Eco-Station 15: Disturbance Succession

Ecological Succession and "Climax" Communities - Ecological vegetation succession occurs when older, simple plant communities are replaced by newer more complex communities. Basically, it is a change in species composition over time. Each successive community alters the physical environment in a manner that makes the area better habitat for other later communities. It is home improvement followed by eviction. Hypothetically, succession will lead to an "ultimate" community or climax community - a community that is in perfect equilibrium with the surrounding physical conditions. The climax community is stable and self-sustaining. While communities do progressively change over time and do often become more complex, climax community development is more of a notion or generalist guide used to make predictable assumptions about later communities. In reality, natural and human induced disturbances are common and constantly disrupt the sequence of a seemingly fated "ideal" community. Nature is in constant state of adaptation.

New Island Community Composition - The Climax community on New Island would mostly consist of an overstory with American elm in the interior and Red maple and sycamore along the Rivers edge. The understory would be largely made up of American Hornbeam. Because rivers are dynamic, disturbances from high water events are normal. Even on dammed, highly regulated rivers, such as the Upper Susquehanna, flood events do occur. Therefore, would be climax communities are not fully realized. A real mixture of species and community types persist on New Island.

Primary and Secondary Succession and Pioneer Species - Primary succession on New Island is unlikely, with the exception of plant communities exactly on the river's edge. Primary succession occurs in an area of bare rock, where the disturbance left no vestige of former community. More common to the Island is secondary succession. Following a disturbance, secondary succession will begin because some aspects of the previously functioning community remain in place. Pioneer species are replaced by later-stage successional plants. New Island was heavily farmed in the past. Agriculture is a human-induced disturbance on the natural landscape. As agriculture was abandoned, farmed fields underwent secondary succession. Pioneer grass species replaced crops later, shrubs such hawthorn and honeysuckle replaced grasses, and next, trees such as Poison sumac and Black locust replaced shrubs.