You raise some good points, Dr. Hayes, and I've been struggling with the problem of including these variations while still try to keep the concept simple (that's the trouble with ecology, what looks simple on the surface always becomes much more complicated as you dig into it).
The simple categories I suggest would lump any natural grassland or shrub-grassland, including your private grazed grasslands if they are sufficiently diverse, all together as rangelands which are part the managed resource lands category. Less diverse grasslands managed primarily for forage might be in the pastureland/rangeland category. Pastured farm land would be like croplands -- places where a monoculture forage crop is being maintained. These are all based on categories used in the University of Oregon's Oregon Atlas. The challenge is, of course, using categories that include all land/habitat variations in the area being considered (Oregon, in my case), allowing for some subjectivity in deciding what category a particular piece of land best fits into, and still coming up with a simple, useable system. The risk is getting snarled up in fruitless debates over what category a particular piece of land should be put in -- in your California case a prospective developer might say that a privately owned, cattle grazed grassland is really not much better than farm cropland or even urban lawns, thus resulting in a lower habitat repayment. You might argue that the privately owned, cattle grazed grassland has a habitat value at least as high as managed resource lands, resulting a much high repayment schedule for the developer. If this is indicative of a real problem and it's not possible to come up with a simple resolution, scientifically or socially, the system probably has no legs. Warren W. Aney Tigard, Oregon -----Original Message----- From: Ecological Society of America: grants, jobs, news [mailto:[EMAIL PROTECTED] Behalf Of Grey Hayes Sent: Saturday, June 14, 2008 07:56 To: [email protected] Subject: [ECOLOG-L] Ecosystems, faux ecosystems, and habitat valuation Hi Warren, Your work valuing ecosystems is very interesting, and I'm looking forward to seeing more.? I want to suggest one caveat for your work to see if you might be able to integrate it. On California's coast, according to my and others' research, it appears that privately owned, cattle grazed grasslands might be valued in your schema more highly than publicly owned, ungrazed grasslands.? I understand some of the same ecological processes might be at work in your state where unmanaged (eg., 'wilderness') areas often have some of the major disturbance regimes suppressed, negatively impacting disturbance-dependent native plant species. In California's vernal pool systems of the Sacramento Valley, research suggests a similar story, but also more clearly affecting native wildlife populations. And so, your valuation system might need to address (especially) grassland ecosystems where privately managed land might be able to maintain some elements of biodiversity more than on underfunded public lands. Grey Hayes, PhD Coastal Training Program Coordinator Elkhorn Slough National Estuarine Research Reserve Moss Landing, California, USA -----Original Message----- From: Warren W. Aney <[EMAIL PROTECTED]> To: [email protected] Sent: Fri, 13 Jun 2008 10:31 pm Subject: Re: [ECOLOG-L] Ecosystems and faux ecosystems Re: [ECOLOG-L] Wetland creation Wayne, Bill, Andy, Amartya, et al., I'm in the process of relating all this discussion to a project I am currently working on and I have found our exchanges helpful. The basic question I've been working on is: how do we determine the actual per land unit value of habitat (= ecosystem) that is modified or destroyed? To put it most simply, if, in a given area, broadly defined wildlife related activities each year create $2 billion in economic activity and we have 50 million land units of habitat, then each land unit is worth $40 in terms of annual economic activity. However, different categories of land have different habitat values: A natural (or restored) wetland will have more value than a created wetland, and this will have more value than a drained wetland. A late successional forest will have more habitat value than a tree farm, which will have more habitat value than a golf course, which will have more habitat value than a housing development. So, for this project I arbitrarily assigned relative habitat values by land category: RHV 1.0: Protected natural areas (ecosystems in Late Successional Forest Reserves, Wilderness Areas, National Wildlife Refuges, National Parks and Monuments, state wildlife areas, etc.). A protected natural wetland or late successional forest would fall into this category. RHV 0.90: Managed resource lands (rangeland, public and private forestland, etc.). A restored wetland might fall into this category. RHV 0.70: Pasture/rangeland (mostly privately owned). A tree farm might fall into either this or the previous category, depending on how it is managed. A created wetland might also fall into this category. RHV 0.50: Farm cropland (harvested and pastured farm land). A golf course might also fall into this category. RHV 0.05: Urban built-up area (residential, industrial, commercial, institutional land, etc.). RHV 0.00: Roads and railroads. Using these relative habitat values, the total economic activity generated in the state of Oregon by wildlife (and fish) related activities in a recent year, and the state acreage in each of the above land categories, I came up with the following per acre per year values: $40.56 for each acre of protected natural areas $36.50 for each acre of managed resource lands $28.39 for each acre of pasture/rangeland $20.28 for each acre of farm cropland $2.03 for each acre of built-up areas $0 for each acre of roads and railroads (These figures, multiplied by total land area in each category, sum up to the total economic activity of $2,074 million.) How can these figures be put to use? Let's say that one acre is changed from managed resource lands to a built-up area. The reduction in wildlife habitat value is $34.47 (the difference between $36.50 and $2.03). In order to provide $34.47 per year in repayment value, at an annual interest rate of 6% this developer could contribute or mitigate a total one-time dollar value of $574.50 per acre. These figures and categories are for the purpose of initiating discussion and will probably be changed and refined if the process takes hold. But I think the basic concept has merit and can be useful when assessing the economic effect of land use changes when wildlife habitat is either degraded or improved. There is one caveat I've tried to remember: if this system is to be used and understood by a wide variety of decision makers, administrators and land managers, it has to be kept reasonably simple. If anyone wants more details, I'll be glad to share a more detailed write-up and the actual spreadsheet with formulas. Meanwhile, I'd be pleased to receive your reactions, suggestions and criticisms (I know you're all good at the latter). Does this seem to have merit? Is anyone aware of similar attempts along this line by others? Warren W. Aney Senior Wildlife Ecologist Tigard, OR 97223 (503) 246-8613 phone (504) 539-1009 mobile (503) 246-2605 fax [EMAIL PROTECTED] > >
