## 4 Discussion  
Degraded lands have limitations related to soil depth, nutrient deficiencies, moisture issues, etc., and for this reason, these lands are inhospitable for carrying out restoration activities [31]. The present study shows that both the _A. saligna_ and _C. equisetifolia_ species planted in the \(T\) had relatively good  
Figure 7: Mean above-ground biomass (AGB), (**A**,**B**), belowground biomass (BGB), (**C**,**D**), and total biomass (TB), (**E**,**F**), of _A. saligna_ (AS) and _C. equisetifolia_ (CE) planted and grown in a trench (_T_) and a plantation pit (_P_) in 2020. Grouping letters are given above the bars (species-wise comparisons via _t_-test at \(p=0.05\)).  
growth (DBH and height increment) as compared with that of the same species planted and grown in the \(P\). This could indicate that the moisture harvesting structure (trench) established in the degraded land served as one of the treatments to facilitate the growth of the planted species. Such a facilitation role of the trench in improving the growth and the biomass of the trees could be associated with its ability to trap runoff water and infiltrate it into the soil, which could help the planted trees utilize it for growth also during a substantial part of the dry season. [PERSON] et al. [32] and [PERSON] et al. [33] described that soil moisture conservation structures reduce runoff and help the infiltration of rainwater during the rainy season. Rainwater is then available for plants during the dry period, which vigorously enhances plant growth and increases plant biomass compared with that of trees planted without moisture harvesting structures, i.e., planting pit only. [PERSON] and [PERSON] [34] reported that the performance of tree species increased in continuous trenches, which was attributed to increased moisture availability for the growth of plants. The present study result is in line with the findings of [PERSON] et al. [32], who reported that _Acacia auriculiformis_ planted with a soil and water conservation structure had better growth and productivity than those of species grown only in a tree-planting pit. [PERSON] et al. [27] also reported that rainwater harvesting structures resulted in higher growth of _Emblica officinalis_ on degraded land than in only a pit. [PERSON] et al. [21] also found that compared with that planted in a normal pit, _A. saligna_ species planted in a trench and eyebrow basin structures produced 68%, 95%, and 52% increases in root collar diameter, DBH, and height, respectively.  
BGB and AGB values of _A. saligna_ planted in the \(T\) were greater than those planted only in the \(P\). The rainwater harvesting structure therefore not only favours diameter and height increments in the studied species but also facilitates their biomass productivity on the degraded land. [PERSON] [23], in a study on the restoration of degraded lands, recorded higher biomass production of _Acacia catechu_ in a contour trench and V-ditch than in a plantation pit. Similarly, [PERSON] et al. [35] found that soil and water conservation measures such as terraces and trenches contributed to relatively high biomass production in _Achras zapota_ trees. Our study results showed no significant differences between the biomass production of _A. saligna_ and _C. equisetifolia_ planted in the \(T\). Similarly, there were no significant differences between the total biomass production of _A. saligna_ and _C. equisetifolia_ planted in the \(P\). These results could further indicate that the two studied species performed equally on the degraded land of a semi-arid region. However, there were significant differences between the species planted in \(T\) and \(P\), which shows that the differences in the biomass values were much more influenced by the rainwater harvesting structure than the planted species. In contrast to the results of our study, [PERSON] et al. [36] reported a variation in the performance of 45 native tree species on degraded land.