Question

descriptions
a long - term variance in the average weather patterns that have come to define earths local, regional and global conditions
a biological community of interacting organisms and their physical environment; a complex network of interconnected elements
the application of ecological principles to agricultural systems and practices, or the branch of science concerned with this
the application of operations, practices, and treatments to protect land and enhance its performance
answers

Explanation:

1. Climate change: The description mentions a long - term variance in average weather patterns (which is a key aspect of climate change).
2. Ecosystem: A biological community of interacting organisms and their physical environment is the definition of an ecosystem.
3. Agroecology: It is the application of ecological principles to agricultural systems.
4. Land management: The application of operations, practices, and treatments to protect land and enhance its performance is land management.

Answer:

1. Climate change
2. Ecosystem
3. Agroecology
4. Land management