What group conquered Jerusalem in 1071?

Seljuk Turks

Beginning in the 11th century, Christians in Jerusalem were increasingly persecuted by the city's Islamic rulers, especially when control of the holy city passed from the relatively tolerant Egyptians to the Seljuk Turks in 1071.

these conditions long with a short growing season made farming difficult.

explanation:

the north has a climate of warm summers and snowy cold winters. the terrain is rocky, hilly, and not good for farming.