In February of 1861, Alexander II emancipated serfs in Russia. Serfs were very much like slaves, but different in that they were attached to the land. If a piece of land was sold, serfs stayed with it and served the new landowner. Before the emancipation (what Fiers calls "the disaster"), there were more than 22 million serfs in Russia, 44% of the population. This new freedom affected not only the serfs, now unemployed, but also the landowners, who couldn't thrive without the cheap labor. Rural areas were still adjusting to the shock forty years later, when Chekhov wrote The Cherry Orchard.
Setting the first scene in the nursery, Chekhov immediately establishes Lubov's intense emotional relationship with the past. Her first line is "The nursery!" Looking around, she feels like a little girl again. It's going to be very hard for her to part with this place.
This act feels like a pastoral scene from Shakespeare. Love is in the air, servants tease each other, a guitar strums, and Trofimov muses on the future of man. The outdoor setting allows us to spy on interactions that could never happen in the house: the tryst between Dunyasha and Yasha, the flirtation of Trofimov and Anya, and, of course, the encounter with the homeless man. In this act, we get more closely acquainted with the beauty of the orchard, the main subject of contention.
How typical: Lubov throws a party while others decide the fate of the estate. The party in the ballroom serves a number of purposes. With dancing, Charlotta's magic tricks, and a few moments of slapstick, it's a theatrical contrast to the pensive mood of Act 1. It highlights the decline of the household (as Fiers mentions, "At our balls some time back, generals and barons and admirals used to dance, and now we send for post-office clerks and the Station-master, and even they come as a favour" [4.75]). It's also a last hurrah for the household, as though Lubov knows her fate is sealed.
The empty nursery, stripped and filled with luggage, visually represents the change that has come over the house and family since Act 1. Lubov had been so delighted, so comforted to return to the nursery, and now she's leaving it forever.