What are some ways to preserve land?

I am not sure I understand what you are looking for.  Are you asking about ways to preserve land for the future?

One way to preserve or conserve our land is to stop deforestation. ...

Before we think of ways of preserving land we need to be clear about the exact nature o preserving the land. Preservation of land may mean preserving specific qualities or features of land or it may also mean actual reduction of land area nu flooding from sea water or by other water  bodies.

The means of preserving the land will depend on exact nature of threat posed to the land. The biggest threat to flooding of land is posed by the likely melting of polar ice caps. Preserving land from this threat requires stopping further increase in global warming levels, and possibly reducing. Many initiatives to do this are already underway. Though the progress is not much so far, it is hoped that good sense will prevail ultimately and this great threat to humanity will be averted.

Another major damage to land is because of deforestation. This causes many other problems lie changing the pattern of balance of ecosystem and land erosion. Deforestation also contributes to global warming. The steps to reduce this problem is to avoid clearing of forests for industry, human habitation for any other use, and undertaking plantation of trees.

There are many other threats to land with different solutions to handling them. These are too numerous to be even listed on this forum.