Climate Change Effects on Temperate Grassland and Its Implication for Forage Production: A Case Study from Northern Germany

Abstract

The effects of climate change on agricultural ecosystems are increasing, and droughts affect many regions. Drought has substantial ecological, social, and economic consequences for the sustainability of agricultural land. Many regions of the northern hemisphere have not experienced a high frequency of meteorological droughts in the past. For understanding the implications of climate change on grassland, analysis of the long-term climate data provides key information relevant for improved grassland management strategies. Using weather data and grassland production data from a long-term permanent grassland site, our aims were (i) to detect the most important drought periods that affected the region and (ii) to assess whether climate changes and variability significantly affected forage production in the last decade. For this purpose, long-term daily weather data (1961–2019) and the standardized precipitation index (SPI), De Martonne index (IDM), water deficit (WD), dryness index (DI), yield anomaly index (YAI), and annual yield loss index (YL) were used to provide a scientific estimation. The results show that, despite a positive trend in DI and a negative trend in WD and precipitation, the time-series trends of precipitation, WD, and DI indices for 1961–2019 were not significant. Extreme dry conditions were also identified with SPI values less than −2. The measured annual forage yield (2007–2018) harvested in a four-cut silage system (with and without organic N-fertilization) showed a strong correlation with WD (R = 0.64; p ˂ 0. 05). The main yield losses were indicated for the years 2008 and 2018. The results of this study could provide a perspective for drought monitoring, as well as drought warning, in grassland in northwest Europe.

Climate Change Can Accelerate Depletion of Montane Grassland C Stocks

“…Plant stress in the drier 2015 as compared to 2014 is further supported by significant yield (ANPP) reductions mainly under intensive grassland management (Table 2), indicating a higher resistance of extensively used grasslands to drought. Yield reductions (2015 vs. 2014) of 35% compare well with numbers reported for a four-cut grassland system in N-Germany (Emadodin et al, 2021). We found that GPP between intensive and extensive treatments was not statistically different but ANPP (Table 3) was significantly lower in extensive treatments.…”

Effects of dry spells on soil moisture and yield anomalies at a montane managed grassland site: A lysimeter climate experiment

“…Similarly, Emadodin et al (2021) found large annual fluctuations in the occurrence of wet and dry events based on the analysis of SPI in Northern Germany. In almost all decades between 1961 and 2019, severe droughts with SPI values lower than À2 were recorded, but three of the five most severe events occurred in the period from 1990 to 2020 (Emadodin et al, 2021). The statistical analysis showed no significant trend for SPI and PDSI at our study site.…”

“…The dry matter yield was determined using a method adapted from the Association of German Agricultural Inspection and Research Institutes (VDLUFA, 2013). Three samples of fresh aboveground biomass were taken for each lysimeter (12 samples in total for six lysimeters) and each biomass sample ($600 g) was filled 1) was transformed to the YAI (3) after Emadodin et al (2021).…”

Climate changes in recent decades, the evolution of the drought phenomenon and their influence on vineyards in north-eastern Romania

“…Monitoring the monthly distribution of accessible soil moisture during 2000-2020 has highlighted the low values in the dry and very dry years : 2000: , 2007: , 2009: , 2011: , 2012: , 2017). Among these, the years 2015 and 2020 stand out with extremely low values registered in almost all the months of the growing season -between 23-39%, on the whole depth of the soil profile (0-150 cm).…”