How it Works
After researching the methods used to prioritize acquisitions in the state, we designed a tool to complement local knowledge of the environmental benefits of a parcel with information on how it compares to parcels throughout the state. Detailed local knowledge gathered in site visits is important for decision making, however, it is impossible to gather site-level data for the entire state. Valuable parcels will be missed without a perspective that considers all of the parcels in Minnesota.
Our approach uses 40 acre public land survey parcels as an approximation for the scale that land management decisions are made. We scored over 330,000 privately held, undeveloped parcels on 11 metrics of public environmental benefits. The average scores of these parcels are displayed next to the scores of a proposed parcel so users can quickly see what benefits a parcel provides, and how exceptional they are relative to the average parcel. This information is useful in conjunction with local expertise; disagreement between the tool’s scores and local expertise is an opportunity to better understand how benefits are perceived, measured, and valued.
Environmental Benefit Metrics
We created 11 statewide metric maps that depict where individual environmental benefits are produced, and how their quality compares to the rest of the state. For example, to contribute to lake recreation, an acquisition must be in the catchment of a publicly accessible lake. Among these, land that contributes to lakes with higher visitation and that are more sensitive to increased runoff pollution have higher scores. The metrics focus on ways in which human wellbeing is influenced by the environment, such as providing recreation opportunities or protecting drinking water. We also include two non-environmental metrics, nearby population and risk of conversion, to help users consider the impact and efficiency of a proposed acquisition. See the metric descriptions page or their expanded documentation for more information on how the metrics were constructed.
We designed the metrics for prioritizing protection of undeveloped land without public access, such as with a conservation easement. Benefits must be provided to the public without access to the parcel, such as by controlling runoff into a public lake or by sequestering carbon from the atmosphere. The metrics all range from zero to one, where zero indicates the benefit is not produced there, and one indicates it is the best place for that benefit in the state. However, due to differences in the distribution of benefits, scores of different metrics are not comparable, and should not be combined. For example, high scores for the groundwater nitrate metric are much rarer than high scores for the wild rice metric. Because of these differences, it is best to only make comparisons between different sets of parcels within individual metrics (e.g. proposed acquisition vs. average of all viable parcels in the state).
Comparisons to Other Parcels
A proposed acquisition’s scores are best interpreted as a comparison to other parcels. The tool’s report shows your proposed parcel’s scores relative to the scores of two comparison sets; the average of all viable parcels in the state, and the average of past LCCMR-funded easements. To define parcels we used the statewide map of 40 acre public land survey parcels. These boundaries conform well to the shape of major features, and offer a good approximation of the scale at which land management and ownership operates. We defined viable parcels as >50% privately held and >50% undeveloped. These 330,000 parcels are not necessary an exact representation of land management or ownership, but represent a realistic comparison set of all viable parcels in the state.
The second comparison set is all LCCMR-funded conservation easements which have spatial and cost data available, representing around 100 acquisitions from 2005 to present. Instead of just comparing the average environmental benefit scores for this set to a proposed acquisition, we calculate their scores divided by their price per acre to produce a metric of return on investment. If the user provides an estimate of the price per acre for a proposed acquisition, they can compare its benefits to those of past acquisitions when cost is taken into account. The cost used for past LCCMR-funded acquisitions is the total project cost, which includes closing costs, and contributions from other organizations.
Our comparison parcel sets filter out parcels that are developed, but the tool does not check whether or not a proposed acquisition is already developed or not. We chose not to mask out developed land in the underlying metrics because inaccuracies in a mask could exclude viable parcels. The user must ensure that the parcel they are proposing is undeveloped for the scores to be meaningful.
Differences between web and desktop tools
We provide a web and desktop interface to the tool. Both tools produce the same report format, but the desktop tool allows users to score the exact boundaries of their parcel, while the web version returns the scores of the nearest 40 acre public land survey parcel to the input point. Both tools assume that the proposed parcel is undeveloped, if the user proposes an already developed parcel, the output scores are not valid. For more information or to download the desktop version, see the desktop version page.