If you preserve something, you take action to save it or protect it from damage or decay.
保护 We will do everything to preserve peace. 我们将竭尽全力维护和平。
If you say that a job or activity is the preserve of a particular person or group of people, you mean that they are the only ones who take part in it.
独揽之事; 独占的活动 ...the preservation of the status quo. …现状的维护。