Mapping and Monitoring
Losing Open Space in Southern Maine: Overview
Maine’s dilemma was summarized by USM economist Charles Colgan in 2003: “We are right at, or beyond, sustainable harvest levels from the forests and oceans, and we do not have the knowledge that will get us there. The land base is shifting rapidly from resource to urban uses. We have profoundly conflicting visions of how Maine’s natural resources should be used.”
The area of protected land in Maine is now about 5,300 sq. miles, or about 17% of Maine’s land area (MeGIS, 2010). Of this, York County has only 1.2% of the total area of Maine’s conservation lands and Cumberland County has only 0.7%. The map of the protected lands of New England shows the large and obvious gaps in conserved lands in southern and central Maine (The Nature Conservancy, 2008).
Green areas indicate protected lands.
Added to these challenges are, of course, the complexities brought by a climate that appears to be changing even faster than anticipated. The loss of open space is of special concern for southern Maine due to:
• Greater proximity to urban centers and higher populations nearby. As southern New Hampshire has come to reflect the demography of Massachusetts, southern Maine has followed.
• Greater biological diversity - “Southern and coastal Maine support the highest level of species diversity in the state (Me-GAP report). At the same time, these areas are among those most desirable for development. Some of the state's most rare plant communities have already been lost or altered by development in southern Maine.”
• A longer and more intense land use history with related soil and biotic impoverishment.
• Loss of farmlands and an increase in developed lands with more impervious surfaces.
• Lands in southern Maine are more expensive, making them more costly to conserve and protect.
• Ecosystem services, provided for free by remaining intact ecosystems, are even more valuable in southern Maine.
• There are more family-owned lands in southern Maine.
Predicted Relative Climate Shifts: Maine’s climate to become more like Maryland’s
Climate change has already begun. Projected future climates show Maine’s current climate shifting “southward” as we approach 2090 and becoming more like today’s mid-Atlantic states of Virginia, Maryland, and eastern Pennsylvania. According to the Union of Concerned Scientists, “Red arrows track what summers could feel like over the course of the century under the higher-emissions [CO2] scenario; orange arrows track what summers in the state could feel like under the lower emissions scenario” (Frumhoff et al. 2007).
Date of ice-out at Sebago Lake from 1807 to 2010 (number of days past January 1st). Blue points at zero indicate years in which the lake did not freeze. The 2010 ice-out was the earliest ever recorded (NEISA).
Mean annual temperature in Portland from 1891 to 2009. Over that period, the mean temperature has risen from 43.5 to 46o F (NCDC, Wake et al. 2009).
Challenges to the Future of the Environment of Southern Maine
- Climate change and sea level rise
- Continued, if slowed, population growth and development
- Heightened awareness of ecosystem services
- Proximity to Boston and southern New Hampshire
- Increasing imperviousness of the land
- More demands for biomass and energy
- Declining fisheries