human activity speeding the decline of Earth’s biodiversity

 "Healing Earth is an environmental science e-textbook written by women and men who share this awe and concern for the natural world. We are an international group of scientists and humanists who imagine—and work for—a cleaner and healthier planet. We are delighted you are exploring Healing Earth and we invite you to join your hopes for a healthy planet with ours."

 A "second aim of Healing Earth is to help you think ethically as you study environmental science, to reflect on the major moral questions in each chapter topic from the standpoint of a coherent environmental ethic."

Here is the chapter on Biodiversity and Ethics:
https://healingearth.ijep.net/biodiversity/biodiversity-and-ethics

See the entire online resource at  https://healingearth.ijep.net/