The researchers compared how much land is needed to support human activities in the Central region over nearly two decades, to see if it's sustainable. They found that from 1990 to 2009, the total land needed increased rapidly, especially in provinces like Shanxi and Henan. They also learned that Shanxi and Henan had high energy needs compared to other regions – 85% in Shanxi! This shows those places need to improve how they use energy and industries. By measuring this, the researchers discovered that Shanxi and Henan had serious environmental problems due to using more land than they should. To keep developing sustainably, these provinces have to change how they produce goods and use technology.