This thesis deals with greenhouse gas emissions (GHGE) from dairy production with a focus on specific protein feedstuffs and on land use and land use change (LULUC). An extension of system boundaries, especially including GHGE related to LULUC, resulted in advantages for dairy production systems (PS) which hardly utilise the LULUC-burdened soybean meal. Within different production methods, PS with a higher milk output generally showed better results for GHGE per kg of milk but higher emissions per ha of land as compared to PS with a lower milk output. The regional location of the farm and a broader setting of system boundaries additionally influenced emission loads. Furthermore, the consequences were estimated of a substitution of protein feedstuffs which are specifically loaded with high GHGE from land use change (LUC). Highest GHGE were found for extracted soybean meal, medium GHGE were found for distillers dried grains with solubles, for cake and extracted meal from rapeseed and for lucerne cobs. Cake and extracted meal from sunflower seeds as well as faba beans were connected to the lowest GHGE. Substituting soybean meal by nutritionally equivalent mixtures of alternative protein feedstuffs, resulted in an average reduction of GHGE of 42 %. With a focus on emissions from LULUC, this work suggests that GHGE which are included in assessments should be restricted to physically occurring fluxes of greenhouse gases and should exclude hypothetical sources. The results show that almost a quarter of the increase in CO2 concentration which occurred during the last 250 years originates from LULUC with a rather drastic impact of LUC occurring during the last few decades. Thus, CO2 emitted from both soil and vegetation due to LUC shall be considered within accounting periods of ten or 20 years. The length of these accounting periods is consistent with the timescale of soil carbon losses from isolated areas, remaining in the atmosphere.