Read the passage and answer the questions that follow.
We should preserve nature to preserve life and beauty. A beautiful landscape, full of green vegetation, will not just attract our attention but will fill us with infinite satisfaction. Unfortunately, because of modernization, much of nature is now yielding to towns, roads and industrial areas In a few places, some natural reserves are now being carved out to avert the danger of destroying nature completely. Man will perish without nature, so modern man should continue this struggle to save plants, which give us oxygen, from extinction. Moreover, nature is essential to man's health.
What does "Nature" in the passage mean?