# Life Cycle Assessment of Land Use Trade-Offs in Indoor Vertical Farming +
## 3 Results and Discussion
### LANCA Results
particular, the PV scenario shows notably higher values for Erosion Potential (EP) (0.50 kg vs. 0.22 kg in GM) and Groundwater Regeneration Reduction Potential (GRRP) for both Occupation and Reversible transformation (\(-3.24\times 10^{-3}\) m\({}^{3}\) and \(-1.86\times 10^{-3}\) m\({}^{3}\), respectively, compared to \(-7.03\times 10^{-3}\) m\({}^{3}\) and \(-4.11\times 10^{-3}\) m\({}^{3}\) in GM). These values indicate that while rooftop PV reduces operational land pressure, its component manufacturing and material sourcing can contribute to adverse effects on soil stability and groundwater recharge. Other major contributors to these impacts are seed production and transportation, followed by carton box production. Seed production is the primary driver in both EP and GRRP, accounting for 152% of land occupation and 112% of land transformation in EP, and 289% of land occupation in GRRP. In GRRP for land transformation, the carton box process leads, contributing 60% of the total impact. For the Soil Organic Carbon Reduction Potential (SOCRP) indicator, the GM scenario shows greater contributions for land occupation, driven by seed production (195%) and photovoltaic electricity production from open-ground systems (150%). Conversely, PV exhibits clear advantages in SOCRP, showing a beneficial negative value under occupation, suggesting that processes, including composting, may contribute to soil organic storage. For land transformation in this same indicator, the PV scenario is majorly influenced by the seed process, which contributes 110% of the impact. These findings emphasize that although PV systems offer significant benefits in minimizing operational land occupation and climate change impacts, a full life cycle perspective is essential. It is important to note that contributions exceeding 100% occur when other processes in the system yield negative impacts, often referred to as avoided burdens. These compensatory effects are discussed in more detail below. Figure 5 below presents the relative contributions to each category from the main system processes: Construction, Installation, Cultivation, Packaging and Delivery. Here, the relative shares are normalized to the total value of the respective indicator. As can be seen, Cultivation emerged as the primary contributor across nearly all categories in both GM and PV scenarios. It accounted for the vast majority of impacts on the Reversible transformation categories, particularly in EP and SOCRP, demonstrating almost total influence. Packaging also contributed significantly to the BLP of land occupation,  
Figure 5: LANCA relative contributions from the five life cycle processes. The indicators are grouped by land use type: Occupation and Reversible transformation. Each bar displays the percentage contribution of each process to the total impact per indicator and scenario. BLP = Biodiversity Loss Potential; EP = Erosion Potential; GRRP = Groundwater Regeneration Reduction Potential; IRP = Infiltration Reduction Potential; PFRP = Physicochemical Filtration Reduction Potential; SOCRP = Soil Organic Carbon Reduction Potential. where in the PV scenario it exceeded the contribution of Cultivation, representing 58% of the total relative impact in this category. Delving deeper into the analysis, the negative impact on biodiversity is primarily linked to the carton box production used for packaging. Although outcomes may vary depending on management practices, producing cartons from forest fiber extraction can result in species displacement, habitat fragmentation, and ecosystem loss [56; 57]. Interestingly, the same process also contributes positively (negative values in Figure 5 representing environmental benefits or avoided impacts) to the EP and GRRP indicators for land occupation. Those benefits refer to avoided impacts associated with packaging. These benefits arise from the origin of carton boxes in forestry, which can enhance soil stability, support groundwater recharge, and reduce erosion.