*2.2. Experimental Design*

The experiment was laid as a paired t-design to compare the effects of conservation practices and irrigation systems. The paired t-test is mathematically powerful in comparing two-paired measurements that have intrinsic relationships and allows good control of individual differences without necessarily having a large sample size [46]. De Winter [47] proved the applicability of paired t-test as low as two replicates. Several studies, including Yimam et al. [22], Belay et al. [26], and Assefa et al. [11] have used paired-t design for similar purposes. The experimental design and setup were described for each site (i.e., Alefa and Affesa) separately as shown below.

**Figure 1.** Location map of experimental sites in the northern part of Ethiopia.
