Examining the effects of mowing, irrigation, and fertilization on plant productivity and soil carbon levels of perennial cropping systems

With the growing concern of climate change, there is increasing pressure on the agricultural industry to alter management techniques to become more environmentally sustainable while still maintaining production of quality crop yields. Three commonly used management techniques, mowing, irrigation, and fertilization, were tested on plant and soil characteristics to determine the best practices for managing land to be both productive and sustainable. Two enclosures were established on a perennial cropping system in the interior of British Columbia. One enclosure was constructed on active cropland that was irrigated and fertilized. A second enclosure was located on abandoned cropland which had not been irrigated or fertilized for over twenty years. Within the active enclosure, different mowing heights were implemented, ranging from zero to thirty centimetres at five-centimetre intervals. Treatments were applied twice throughout both 2020 and 2021 growing seasons. Measures of plant community dynamics, plant productivity, forage quality, and soil properties were taken from within both enclosures throughout the duration of the study. Results showed that each of these three management techniques effected plant productivity and soil carbon. Mowing height altered forage species composition, plant productivity, forage quality, and soil properties. Use of a 10 cm cutting height produced highest levels of plant productivity and soil carbon. The abandonment of irrigation and fertilization was shown to cause unfavourable plant community changes along with decreases in plant productivity, forage quality, and soil carbon. These results provide insight on the use of these three management techniques within perennial cropping systems and their effects on levels of plant productivity and soil carbon. The implications of this study allow producers throughout interior British Columbia to make informed decisions on how to manage their land for optimum productivity and environmental sustainability.