important-plant-areas-of-new-mexico

The New Mexico Energy, Minerals and Natural Resources Department was created in 1987 through a merger between the Natural Resources Department and the Energy and Minerals Department. The individual administrative pieces of the department have been around much longer than that, though.

The State Parks Commission was established in 1933, followed by the Oil Conservation Commission in 1935 and the Soil and Water Conservation Commission in 1937. The latter group was transferred in 1997 to the Department of Agriculture.

The Department of State Forestry was created in 1957. The Coal Surface Commission was formed in 1972.

Both the original Energy and Minerals Department and the Natural Resources Department came into being in 1977 and existed as separate agencies until the 1987 merger.

The New Mexico Youth Conservation Corps was established and administratively attached to EMNRD in 1992. The following year marked the creation of the Mining Commission.

The present-day Energy, Minerals and Natural Resources Department consists of seven divisions and employs approximately 415 people at 48 different work sites around the state.

nm-environment-minerals-natural-resources-department

New Mexico Energy Minerals & Natural Resources Department

Important Plant Areas (IPAs) are a product of The New Mexico Rare Plant Conservation Strategy. The strategy is an integral part of the State of New Mexico’s Energy, Minerals, and Natural Resources Department, Forestry Division’s Forest Action Plan, which identifies natural resource conditions, needs and opportunities across all land ownerships in the state and guides long-term Division management. What follows is an in-depth explanation of the methodology used to create the IPAs. 

Methodology
IPAs are specific places across New Mexico that support either a high diversity of sensitive species or are the last remaining locations of our most endangered plants. The IPAs were developed using a combination of spatial modeling of the Strategy species observation data in a GIS and expert review followed by the assignment of a Biodiversity Rank (Table 1) to assist in prioritizing areas for conservation planning. 

IPA Delineation 
We downloaded Strategy plant observation data from NHNM Biotics on February 1, 2017 and intersected all Strategy species occurrences with a one-mile hexagonal grid covering the state of New Mexico. This resulted in about 3,000 occupied hexagons attributed by Strategy species composition. This dataset was the foundation for aggregating spatially proximal and compositionally similar hexagons into coherent IPAs. 

Initial clusters representing incipient IPAs were created by visually grouping hexagons in close physical proximity to each other. We deliberately made the initial clusters small with the goal of combining initial clusters into larger clusters in later steps. Hexagons that were completely isolated (>5km from the nearest hexagon) were given their own group identities. 

To reduce the number of small isolated hexagons, we removed any hexagons that fit the following criteria: (1) >5km from the nearest hexagon, (2) no more than 1 Strategy species occurring in the hexagon with a (2) NHNM G-rank of 4 or 5 and an S-rank of 3, 4, or 5. This effectively removed isolated hexagons with low species richness that lacked highly-ranked species. 

We summarized plant occurrence data per initial group as simple presence/absence data for each of the Strategy species. We calculated the geometric centroid of each initial group by calculating the mean x and y coordinates of all hexagons within that group. We then calculated the physical distance between each initial group and every hexagon in the state. Additionally, we estimated the floristic distance between each initial group and every hexagon in the state by using a Euclidean distance metric based on all species. We flagged as potential outliers hexagons within a group that were further than 5,000 m from the geometric center of group and that had a floristic distance to their own group >50. For each of these hexagons, we estimated the next best grouping using a combination of physical and floristic distance and reassigned the hexagons as needed. 

Final hexagon groupings were created using expert knowledge of local geography and general Strategy species habitat requirements, while taking into account pairwise floristic and physical distances. After assigning hexagons into final groups, we used Fixed r Local Convex Hulls in ArcGIS to define the final IPA boundaries. We estimated the r parameter individually for each group by calculating the median of all pairwise distances between hexagons within each group. This allowed a more inclusive wrapping for hexagons that were spread over a large geographic area and tighter, more exclusive wrapping for hexagons that were tightly clumped. We hand edited individual IPA boundaries to prevent adjacent IPAs from overlapping.