Objective: The focus of this research is the evaluation of the performance of a microsprinkler irrigation system used in a black pepper plantation in a municipality in the northeast of Pará, with emphasis on standards of uniformity and efficiency of water application. Theoretical Framework: The research is based on the concepts of Christiansen's Uniformity Coefficient (CUC) and Distribution Uniformity Coefficient (CUD), which measure irrigation uniformity; Coefficient of Variation in Flow (CVQ), which evaluates the variation in emitter flow rates; and Application Efficiency (Ea), which assesses the proportion of applied water effectively utilized by plants. These parameters, classified according to expert criteria, are essential for evaluating irrigation system performance and identifying the need for technical improvements to optimize water use in agriculture. Method: The research was conducted in the northeastern region of Pará, in an area of 0.194 hectares cultivated with different varieties of black pepper, where the micro-sprinkler irrigation system was evaluated. The irrigation system, consisting of a main polyethylene line, a PVC distribution line, and six lateral lines with emitters delivering 91.5 L/h installed at a height of 2.90 meters, was analyzed for water distribution uniformity and efficiency. Data collection was performed on 16 emitters, distributed across four selected lateral lines, using precipitation collectors and a stopwatch during 4 hours of system operation. Performance indicators (CUC, CUD, CVQ) were calculated based on the data obtained from the evaluations, following established methodologies. Results and Discussion: The research revealed that the micro-sprinkler system exhibited technical deficiencies in several critical aspects. The average flow rate of the emitters was 99.5% below the manufacturer's specification, indicating service pressure issues. Despite this, the uniformity coefficients (CUC of 87.49% and CUD of 78.83%) were classified as "good," suggesting that the system distributes water relatively uniformly. However, the water application efficiency (Ea) was deemed "unacceptable" at 74.89%. Low pressure and improper emitter height, combined with inadequate maintenance, were identified as primary causes of the low efficiency and flow variation (CVQ of 15.18%). These results underscore the need for adjustments in system sizing and management, as well as interventions to enhance uniformity and efficiency, such as lowering the emitters, which could mitigate wind effects and improve system performance. The study suggests that without technical improvements and more rigorous maintenance, economic and water resource losses may persist, jeopardizing the sustainability of black pepper production in the region. Research Implications: The practical and theoretical implications of this research are substantial, offering critical contributions to the fields of agricultural engineering and irrigation management. The results highlight the need for optimization of micro-sprinkler systems, emphasizing that precise adjustments in system design and rigorous maintenance are crucial to ensuring water distribution uniformity and maximizing hydraulic efficiency. These findings not only reinforce agricultural sustainability but also reveal the interdependence between well-planned irrigation practices and the economic viability of high-value crops, such as black pepper, particularly in regions vulnerable to resource scarcity and technical challenges. Originality/Value: This study makes a significant contribution to the literature by introducing an innovative approach to the evaluation and optimization of micro-sprinkler systems for black pepper, demonstrating how technical adjustments and rigorous maintenance can address practical challenges and enhance water efficiency. The findings have direct implications for agricultural sustainability and economic viability, providing crucial guidelines for professional practices and advancing knowledge in agricultural engineering.

Black pepper (Piper nigrum L.) is an important crop in Pará, Brazil; however, irrigation management remains one of the main constraints to achieving stable productivity and high essential oil yield. By determining soil water tension for rational irrigation management that ensures high agronomic performance of black pepper, it is possible to optimize irrigation water use efficiency through monitoring critical soil moisture with the aid of tensiometers. This study evaluated yield, water use efficiency (WUE) and essential oil yield of two black pepper genotypes under five soil water tensions (15–55 kPa) using a split-plot experimental design. The Uthirankotta genotype showed higher yield and WUE, reaching maximum values at 35 kPa, whereas the highest essential oil extraction yield occurred at 15 kPa. Positive correlations were observed between essential oil yield and the main productive traits. Therefore, cultivation of the Uthirankotta genotype under tensiometer-based irrigation management is recommended under the edaphoclimatic conditions of Pará, using a critical tension of 35 kPa as a reference to increase productivity and optimize irrigation water use efficiency, considering the differential genotype response to irrigation management under humid tropical conditions.