Federal agencies and conservation groups announced Wednesday that they would invest millions of dollars to protect additional lands in the Nanticoke watershed and adjacent Blackwater National Wildlife Refuge.

The areas make up what has been identified as a “Sentinel Landscape” by the departments of Defense, Agriculture and Interior and could attract nearly $10 million in land conservation spending from agencies and land conservation groups through 2017.

The Sentinel Landscapes are areas with rural working lands and valuable natural resource features which also overlap with areas important for national defense. In this case, the landscape is under a portion of the Atlantic Test Range used by aircraft from the Naval Air Station Patuxent River.

The air station and Fort Huachuca in Arizona, which was also announced Wednesday, were the first designated sentinel landscapes.

The designation clears the way for the Department of Defense, as well as the departments of Agriculture and Interior, to increase and coordinate their land protection efforts in the designated area.

Altogether, the agencies — working with the states of Maryland, Delaware the Chesapeake Conservancy, The Nature Conservancy and the Conservation Fund — hope to preserve at least 1,385 additional acres as part of a broader effort to protect a wildlife corridor of forest, wetlands and farmland along the Nanticoke.

The land is under a portion of the 2,360 square miles of restricted air space used for test ranges by the Patuxent station. The goal of the project is to ensure that land under that airspace remains rural in order to reduce conflicts from noise, as well as alleviate safety issues, related to training exercises, while also protecting important resources.

“This is a win-win for both the Atlantic Test Ranges at NAS Patuxent River and the surrounding environment,” said Capt. Heidi Fleming, commanding officer at the Patuxent station. “Designating the Nanticoke Corridor as a Sentinel Landscape maintains our unique flight test and evaluation capabilities at the Atlantic Test Ranges while protecting important habitats for imperiled wildlife species and preserving agricultural land in the area.”

The Nanticoke watershed is one of the most ecologically significant areas in the mid-Atlantic and harbors more than 260 species of rare plants and animals such as the Delmarva fox squirrel and the American burying beetle. The river is also part of the Capt. John Smith Chesapeake National Historic Trail.

“The Nanticoke is a key component of the Captain John Smith Chesapeake National Historic Trail, and one of the few regions that Captain John Smith could still recognize today,” said Joel Dunn, executive director of the Chesapeake Conservancy. “We’re very proud that the Nanticoke was selected as one of the very first Sentinel Landscapes in the country.”

The conservancy is putting $1 million, raised from the Mt. Cuba Foundation, into the effort. DoD is investing $3 million, the Interior Department $150,000, the USDA $1.5 million, and the states of Maryland and Delaware are expected to spend $2 million each.