Association of State Wetland Managers - Protecting the Nation's Wetlands.

For Peat’s Sake: Eye Opening Land Use Trends

For Peats Sake LogoBy Marla J. Stelk, Policy Analyst, ASWM

In November, 2015, President Obama issued a Presidential Memorandum on Mitigating Impacts on Natural Resources from Development and Encouraging Related Private Investment. Essentially it’s a directive for federal agencies to “adopt a clear and consistent approach for avoidance and minimization of, and compensatory mitigation for, the impacts of their activities and the projects they approve.” In response to the memorandum, the U.S. Fish and Wildlife Service (FWS) has drafted their proposed revisions to the U.S. Fish and Wildlife Service Mitigation Policy which was released to the federal register on March 8, 2016 for a public comment period. They will be accepting comments from all interested parties until May 9, 2016.

Eager to learn about the FWS newly revised mitigation policy proposal, I downloaded the PDF and began reading through it this week. Aside from the details of the new policy, I found some very interesting facts about land use trends in the United States. Here is what I learned:

By 1982, approximately 71 million acres of the lower 48 States had already been developed. Between 1982 and 2012, the American people developed an additional 44 million acres for a total of 114 million acres developed. Of all historic land development in the United States, excluding Alaska, over 37 percent has occurred since 1982. Much of this newly developed land had been existing habitats, including 17 million acres converted from forests. A projection that the U.S. population will increase from 310 million to 439 million between 2010 and 2050 suggests that land conversion trends like these will continue.

As someone who is over 40 years old, I have been around long enough to witness a substantial amount of land conversion in various parts of the U.S. where I have lived. I was aware of current consumer and demographic trends and that the world’s population was rapidly increasing, leading toward a greater loss of habitat and a greater increase in developed, impervious surfaces. But when I read the statistic that “of all historic land development in the U.S., excluding Alaska, over 37 percent has occurred since 1982” – that took me surprise. So I decided to dig around a bit and get a better idea of what all these numbers in the millions and billions are really telling us.

landuse032416The USDA Economic Research Service (ERS) has been a leading source of land use estimates for over 50 years, so I started there. According to their 2007 report on Major Uses of Land in the United States (which is an overview of data from 14 Major Land Uses reports by region and State from 1945 to 2007), the United States has a total land area of nearly 2.3 billion acres. Their estimates of land use include forestland at 671.4 million acres, grassland pasture and range at 613.4 million acres, cropland at 408.1 million acres, special uses at 313.5 million acres, miscellaneous uses at 196.7 million acres and urban land uses at 60.6 million acres. Of note is that Alaska somewhat skews their land use estimates since, relative to the contiguous 48 States, it has minimal cropland and pasture but large swaths of forest-use, special-use and miscellaneous other land use.

surfacearea032416The USDA Natural Resources Conservation Service’s (NRCS) Natural Resource Inventory (NRI) is another widely used source of data on land use trends in the U.S. According to their 2012 Natural Resources Inventory Summary Report, published in 2015, “The contiguous 48 states, Hawaii, Puerto Rico, and the U.S. Virgin Islands cover over 1.94 billion acres of land and water; about 71 percent of this area is non-Federal rural land – nearly 1.4 billion acres.” This is a bit different from the ERS estimate of total land area at nearly 2.3 billion acres – by about 360 million acres. And it appears that the ERS estimate only includes land surfaces, not water, so the difference could be more significant. Nonetheless, here is how NRCS breaks down surface area by land cover/use for 2012: Federal land at 405.3 million acres, cropland at 362.7 million acres, CRP (Conservation Reserve Program) land at 24.2 million acres, pastureland at 121.1 million acres, rangeland at 405.8 million acres, forest land at 413.3 million acres, other rural land at 45.4 million acres, developed land at 114.1 million acres, and permanent open water at 52.1 million acres.

landusecomparison032416

Although ERS and NRCS use some different categories and methodologies, there are some noticeable similarities between each agency’s distributions of land uses in the U.S. What pops out at me immediately is that the percentage of developed/urban land compared to total land use is really very similar between each study. ERS estimated it at 3% in 2007. NRCS estimated it at 6% in 2012. Some of the 3% difference can probably be found in what each agency includes in their definition of urban and developed. In short, NRCS has a broader definition than ERS. In both cases, compared to the total amount of cropland, pastureland, and rangeland, the amount of developed urban land is minimal.

pacificecoast32416However, the rate of change is what I find alarming. The NRCS 2012 NRI study claims that “About 44 million acres of land were newly developed between 1982 and 2012, bringing the total to about 114 million acres; that represents a 59% increase. Thus, more than 37% of developed land in the 48 conterminous states, Hawaii, Puerto Rico and the Virgin Islands was developed during the last 30 years.” This is generally in agreement with the FWS text in their proposed revision of their mitigation policy. And it appears that all of this land was developed from either agricultural land or natural habitat.

forestarea032416So what does this mean for wetlands? According to the NRCS study, over half of palustrine and estuarine wetlands are in forest lands (59%). The U.S. Forest Service reports that since 1630, about 256 million acres of forest land have been converted to other uses – mainly agricultural. In 2012, forest land comprised only 33% of the total land area of the U.S. – down from 46% in 1630. That’s a loss of about 257 million acres of forest land since the 17th century (and a substantial increase in fragmentation). A study by Homer et al of the 2011 National Land Cover Dataset (NLCD) states that forests have experienced the highest net losses between 2001 and 2011. The 2011 NLCD documents a continued expansion of urban land use/impervious surfaces. USDA statistics also show that available cropland has been decreasing due to development pressures.

So for Peat’s Sake, all of these trends in land use beg the question – with the world population projected to reach 9.7 billion by 2050, how can we continue to absorb exponential increases in population growth with the increased demand for more cropland to feed an ever increasing number of people who need an increasing amount of developed land on which to live? And of primary importance – how do we accomplish that without severely negatively impacting the ecosystems that underlie our consumption and growth? I wish I could say I have the magic silver bullet, but I don’t. All I know is its going to require a truly significant paradigm shift.

References and Resources

This entry was posted in agriculture, conservation, environment, land use, Land use planning, natural resources, resource management, sustainability, wetlands & agriculture, wetlands protection. Bookmark the permalink.

Leave a Reply

Your email address will not be published. Required fields are marked *

Web Analytics