Effects of Elevated Temperature and High and Low Rainfall on the Germination and Growth of the Invasive Alien Plant Acacia mearnsii

Abstract

The impact of climate change on the germination and growth of invasive alien plants varies depending on the plant species and invasion process. We experimentally assessed the responses of the invasive alien plant Acacia mearnsii to future climate change scenarios—namely, elevated temperature as well as high and low rainfall. Acacia mearnsii was grown at an elevated air temperature (+2 °C), high rainfall (6 mm per day), and low rainfall (1.5 mm per day), and its germination and growth performance were measured over five months. We further examined changes in soil nutrients to assess if the above-mentioned climate change scenarios affected soils. Both elevated temperature and high rainfall did not influence A. mearnsii germination and seedling growth. In contrast, we observed reductions in A. mearnsii germination and growth in the low rainfall treatment, an indication that future drought conditions might negatively affect A. mearnsii invasion. We noted that elevated temperature and rainfall resulted in varied effects on soil properties (particularly soil C, N, Ca, and Mg content). We conclude that both elevated temperature and high rainfall may not enhance A. mearnsii invasion through altering germination and growth, but a decrease in A. mearnsii invasiveness is possible under low rainfall conditions.

Potential distribution of selected invasive alien plants under current and future climate change scenarios in South Africa

“…However, the real case of Prosopis spp to decrease in its expansion in higher emission levels needs further investigation. There are some reports that A. mearnsii may proliferate in changing climate scenarios due to its peculiar traits to adapt to climate change [ 22 , 62 , 64 , 65 ]. Most of these traits are related to the breaking of seed dormancy from soil seed banks [ 22 , 65 , 66 ], increase in water-use efficiency [ 64 ] and nutrient (nitrogen) recycling [ 62 ].…”

“…There are some reports that A. mearnsii may proliferate in changing climate scenarios due to its peculiar traits to adapt to climate change [ 22 , 62 , 64 , 65 ]. Most of these traits are related to the breaking of seed dormancy from soil seed banks [ 22 , 65 , 66 ], increase in water-use efficiency [ 64 ] and nutrient (nitrogen) recycling [ 62 ]. Others [ 51 ] indicate that extreme temperature and lower relative humidity may disrupt its reproduction process.…”

“…Others [ 51 ] indicate that extreme temperature and lower relative humidity may disrupt its reproduction process. Also, extreme precipitation and high rainfall may not enhance the invasive potential of A. mearnsii [ 65 ]. However, all these studies are based on small scale experiments that are not supported by a detailed species distribution study.…”

Protective enzyme activity regulation in cotton (Gossypium hirsutum L.) in response to Scirpus planiculmis stress

“…Moreover, temperature and rainfall are considered to be important climatic factors affecting plant growth ( Khan et al., 2022 ; Kharivha et al., 2022 ). In order to adapt to abiotic stresses such as drought, high temperature and low temperature, plants also reduce the impact of climatic conditions on themselves by regulating defense responses ( Akpinar and Cansev, 2022 ; Vital et al., 2022 ).…”

Vegetation diversity and habitat suitability modeling of the invasive plant Bellucia pentamera in conservation forests of West Sumatra, Indonesia

“…Rainfall played a significant role in shaping the presence and prevalence of invasive plant species, with alterations in the seasonal precipitation patterns due to climate change affecting their growth, survival, and reproductive success. The interplay between rainfall and invasive plant distribution is contingent upon temperature, soil nutrients, and competitive interactions (Kharivha et al 2022). Generally, invasive plant species are expected to expand their distribution beyond their native habitats towards warmer areas in response to changes in climate conditions.…”