Interdependent effects of habitat quality and climate on population growth of an endangered plant

Abstract

Summary 1.To predict the viability of populations, it is essential to clarify how performance depends both on large-scale environmental changes, such as climate warming, and on the local habitat. However, in spite of their potential importance, effects of interactions between large-scale environmental changes and the local environment on population viability have rarely been examined. 2. We investigated how population dynamics of the endangered alpine plant Dracocephalum austriacum depend on local habitat quality and climatic variation, as well as how effects of climate depend on local habitat. We used lasso regression shrinkage and integral projection models to identify effects on vital rates and population growth rates in seven populations over seven annual transitions. 3. Populations on steeper slopes had lower survival and stochastic population growth rate than populations on more gentle slopes. In years with low spring temperatures and high summer temperatures, survival and population growth rate were lower. In addition, the negative effects of high summer temperatures did depend on local habitat quality, being more negative in populations on steeper slopes. 4. Combining the net positive effects of high spring temperature and the net negative effects of high summer temperature on plant vital rates with predicted climate change over the next 30 years suggested that effects on D. austriacum would be relatively small. 5. Synthesis. Our results show that different aspects of a warmer climate may have opposing effects on populations, and that climatic effects may depend on local habitat quality. Such interactive effects should be accounted for when determining effects of large-scale environmental changes on population and community dynamics.

Predicting population viability of the narrow endemic Mediterranean plant Centaurea corymbosa under climate change

“…In contrast to some studies reporting both negative and positive effects of climate change 444 on vital rates (Meer et al, 2016;Meisner et al, 2014;Nicolè et al, 2011), our study documents a 445 consistent negative effect of increased temperature and drought on lower-level vital rates in C.…”

“…In contrast, several studies 46 have documented negative effects of summer temperature on growth rates for other plant species (Aragón-Gastélum et al, 2017;Riba et al, 2002;Shryock et al, 2014). In some cases, a given 48 climatic variable has been shown to have diverging effects on separate vital rates within a species 49 life-history (Csergő et al, 2017;Jolls et al, 2015;Nicolè et al, 2011;Peñuelas et al, 2004;50 Treurnicht et al, 2016). For example, a warm summer increased the flowering probability of 51 Dracocephalum austriacum, whereas it decreased plant survival, leading to reduced effects of 52 climate on population growth rates (Nicolè et al, 2011).…”

“…In some cases, a given 48 climatic variable has been shown to have diverging effects on separate vital rates within a species 49 life-history (Csergő et al, 2017;Jolls et al, 2015;Nicolè et al, 2011;Peñuelas et al, 2004;50 Treurnicht et al, 2016). For example, a warm summer increased the flowering probability of 51 Dracocephalum austriacum, whereas it decreased plant survival, leading to reduced effects of 52 climate on population growth rates (Nicolè et al, 2011). Such opposite effects on population 53 dynamics and demographic processes make it difficult to predict the net consequences of climate 54 change on population viability (Meer et al, 2016;Nicolè et al, 2011).…”

“…For example, a warm summer increased the flowering probability of 51 Dracocephalum austriacum, whereas it decreased plant survival, leading to reduced effects of 52 climate on population growth rates (Nicolè et al, 2011). Such opposite effects on population 53 dynamics and demographic processes make it difficult to predict the net consequences of climate 54 change on population viability (Meer et al, 2016;Nicolè et al, 2011).…”

Using Gaussian Bayesian Networks to disentangle direct and indirect associations between landscape physiography, environmental variables and species distribution

“…These negative and hump shaped relationships to maximum temperature were unexpected since the ranges of H. nobilis and C. majalis extend as far as the Mediterranean Sea (Anderberg and Anderberg, 2015) where both annual and summer maximum temperatures are expected to be much higher than in Sweden. It has been argued that the effect of summer maximum temperatures may be indicative of species responses to summer drought (Ashcroft et al, 2008;Nicolè et al, 2011) as it has been reported that maximum temperature is a better predictor of soil moisture than Topographic Wetness Index (our proxy for soil moisture) during dry periods (Lookingbill and Urban, 2004). Similarly, we cannot exclude the possibility that the negative effects of maximum temperature on H. nobilis and C. majalis were caused by lower soil moisture at the warmer sites, especially in the absence of onsite measurements of soil moisture in the analyses.…”