Most soil quality measurements have been limited to laboratory-based
methods that suffer from time delay, high cost, intensive labor requirement,
discrete data collection, and tedious sample pretreatment. Real-time
continuous soil monitoring (RTCSM) possesses a great potential to
revolutionize field measurements by providing first-hand information
for continuously tracking variations of heterogeneous soil parameters
and diverse pollutants in a timely manner and thus enable constant
updates essential for system control and decision-making. Through
a systematic literature search and comprehensive analysis of state-of-the-art
RTCSM technologies, extensive discussion of their vital hurdles, and
sharing of our future perspectives, this critical review bridges the
knowledge gap of spatiotemporal uninterrupted soil monitoring and
soil management execution. First, the barriers for reliable RTCSM
data acquisition are elucidated by examining typical soil monitoring
techniques (e.g., electrochemical and spectroscopic sensors). Next,
the prevailing challenges of the RTCSM sensor network, data transmission,
data processing, and personalized data management are comprehensively
discussed. Furthermore, this review explores RTCSM data application
for updating diverse strategies including high-fidelity soil process
models, control methodologies, digital soil mapping, soil degradation,
food security, and climate change mitigation. Finally, the significance
of RTCSM implementation in agricultural and environmental fields is
underscored through illuminating future directions and perspectives
in this systematic review.