Agricultural Sustainability and Resilience in the Portuguese-Speaking World: Precision Agriculture for Resource Optimization in Uíge

Abstract

In the context of family farming in the Uíge province, Angola, characterized by traditional practices, low mechanization, and dependence on variable natural resources, arises the problem of low productivity, waste of inputs such as water and fertilizers, and vulnerability to climate variations, aggravated by the absence of technical tools for soil and climate monitoring. This work aimed to develop the SILMA IoT prototype, a low-cost Internet of Things system to optimize agricultural resources in the SILMA Agricultural Cooperative. The methodology adopted a mixed approach: qualitative, with a questionnaire applied to 41 final-year Agronomic Engineering students from Kimpa Vita University; quantitative, with the collection of 8,640 continuous readings from the CWT 7-in-1 sensor (NPK, pH, moisture, soil temperature) and DHT11 (climate), using the buried measurement method with a 10-second interval and a moving average of 30 readings. The qualitative results revealed a young respondent profile with 68.3% practical experience, challenges such as lack of soil information (43.9%) and inefficient irrigation (80.5% by visual observation), barriers to IoT adoption like high cost (80.5%), and high interest in practical training (100%); the quantitative results confirmed alkaline soils (average pH 8.47) and low fertility (N 14.3 mg/kg), generating automatic recommendations for tolerant crops like cassava and sweet potato. SILMA IoT demonstrated potential to reduce waste by 20-30% and increase productivity, with high social acceptability (82.9% project interest).