The effect of precipitation, temperature, humidity, and length of the day on the growth of forage grass and soil pH on an organic farm in Kanta-Häme (Southern Finland)

Abstract

This study was conducted at a farm in the Kanta-Häme region of Finland, which is associated with HAMK University of Applied Sciences and focuses on producing feed for dairy cows. Due to declining forage grass yields over the last three years, the study aimed to investigate external factors influencing grass growth and soil pH. The research considered weather data such as precipitation, humidity, length of the day, and atmospheric temperature, which were correlated with the height, sample weight, canopy cover, chlorophyll count of grass, and soil pH from six selected forage grass fields. Field selection was based on the perennial year of growth, comparing 1st-year and 2nd-year grass fields. Data from the selected fields were collected weekly on Mondays before 10:00h to be precise with the timing of data collection. In contrast, weather data were collected daily from May 6th to July 22nd using local weather station data in Jokioinen. The collected weather data was then converted to a weekly basis for analysis and visualization. The study utilizes Pearson correlation to examine the relationship between weather factors, grass growth, and soil pH. The results indicated that humidity significantly influences forage grass growth and soil pH. Furthermore, the length of the day positively impacts grass growth and soil pH. At the same time, atmospheric temperature significantly affects canopy cover and soil pH, particularly in the Kanta-Häme region of Finland. However, precipitation does not considerably affect either grass growth or soil pH.

Keywords forage grass, precipitation, humidity, atmospheric temperature, day length, soil pH.