Modeling selected ecological interactions of Panicummaximum in a semi-dry environment enhanced with in situ rainwater harvesting systems

Enabling ecosystems is central to achieving sustainable development goals (SDGs), for which understanding, assessing and modeling ecosystems’ interactions remained proactive research agenda and difficult tasks, especially the agroecosystems of semi-dry environments. This study evaluated and modeled the ecological interactions of Panicummaximum in semi-dry environments enhanced with in situ rainwater harvesting systems (RWH). The field experiment (10 m × 10 m per plot) included two treatments (ridges and terraces RWH) with three replicates in a randomized complete block design in the Gezira State, Sudan. Meteorological, phenological, and soil moisture (0–100 cm) datasets were routinely collected along the season (2020) and statistically analyzed (P = 0.05) using spreadsheets. The adopted in situ RWH systems have significantly ameliorated interactions of P. maximum with the semi-dry environment compared to the control, attested by its increased biomass production (558–635%), improved water use efficiency (85%), and better-quality soil hydrological properties (a reduction of 9–17% in the soil bulk density). Coupled with improved chemical components (crude protein, nitrogen and organic carbon) of P. maximum. The quadratic function provided the best-fitted model (R2 > 0.97) for the leaf area index (LAI) and the plant height (RMSE 0.19–4.1 m2 m−2), with cautions at establishment and peak crop stages. Also, the fresh biomass was significantly regressed on LAI, minimum and maximum air temperatures (RMSE = 1.1–1.6 t ha−1), among which the minimum temperature negatively interacted with the fresh biomass. Plants’ growth development modelers shall consider the essential differences between rainfed and irrigation conditions in modeling LAI.