If an ancestor owned over 1 acre of land in the UK, including Ireland, in the 1870s they will likely appear in the Return of Owners of Land records.
England & Wales, Return of Owners of Land 1873
Scotland, Return of Owners of Land 1873
Ireland, Return of Owners of Land 1876
According to Wikipedia, the returns, for England and Wales it excludes London, list holdings by size (in acres, roods and poles) and estimated yearly rental of all holdings over one acre. It is laid out by county and landowner, with an identifying address for each landowner.
Wikipedia also mentions that the 1873 Return had inaccuracies (some significant), and a revised edition—The Great Landowners of Great Britain and Ireland—was published in 1883. It’s available through the Internet Archives at https://archive.org/details/greatlandownerso00bateuoft/mode/2up/.