Climate change can have an impact on ecosystems, overwhelming their capacity to mitigate extreme climatic and disturbance events. These may lead to an alteration of the structure, distribution and composition as well as changes in phenology at the species level. Annual plant populations may be particularly affected by these events, as they must regenerate each year primarily by seed. Here, we studied the phenology and composition of annual plant communities while accounting for the species phylogenetic relatedness and their functional traits. We used as a study model the interdunal annual communities of fixed dunes present in the northern coasts of Tuscany. This study is part of a two-year lasting project aimed at analyzing the impact of climate change on coastal and marine ecosystems, financed by the University of Pisa. To achieve our objectives, we identified 10 permanent transects visited once a month for an entire vegetative year with the aim of monitoring the presence and abundance of annual plant species. Each 20 m long transect was randomly selected to ensure homogeneity and representativeness of the study area. Within each transect we annotated environmental characteristics (distance from the sea, altitude, disturbance) and selected ten plots of 0.25 m2 each to quantify plant community composition. For each species we gathered information concerning the following vegetative and reproductive traits that likely influence plant responses to climate conditions: plant height, SLA, LDMC, seed mass and seed dormancy class, as well as seed dispersal and pollination strategy. In September 2020, no annual plants were detected in any plot. The first seedling emergences occurred in the first half of October soon after the early autumn rains. These seedlings belong to Festuca fasciculata Forssk., Marcus-Kochia ramosissima (Desf.) Al-Shehbaz, Medicago littoralis Rhode ex Loisel. and Lagurus ovatus L., which also dominated the communities throughout the year until the end of the vegetative and reproductive phases (July). During the autumn and winter months other frequently occurring species were Cerastium ligusticum Viv. and Draba verna L., which completely disappeared when spring temperatures raised, while M. ramosissima increased its coverage. An even different pattern characterizes Odontites luteus (L.) Clairv., detected since mid-autumn but its frequencies decreased in the winter months, increased in early spring and then decreased again. Catapodium balearicum (Willk.) H. Scholz was instead observed only in May. By using a comprehensive multivariate approach, considering plant co-occurrences and their vegetative and reproductive traits, we will be able to evaluate covariances and trade-offs explaining plant responses to interannual variations in climatic conditions. Specifically, we expect to track phenology and composition of the communities and to understand annual plant species responses to extreme climatic events.

Phenology and composition of annual interdunal plant communities in a climate change context

Daniela Ciccarelli;Angelino Carta
Ultimo
2021-01-01

Abstract

Climate change can have an impact on ecosystems, overwhelming their capacity to mitigate extreme climatic and disturbance events. These may lead to an alteration of the structure, distribution and composition as well as changes in phenology at the species level. Annual plant populations may be particularly affected by these events, as they must regenerate each year primarily by seed. Here, we studied the phenology and composition of annual plant communities while accounting for the species phylogenetic relatedness and their functional traits. We used as a study model the interdunal annual communities of fixed dunes present in the northern coasts of Tuscany. This study is part of a two-year lasting project aimed at analyzing the impact of climate change on coastal and marine ecosystems, financed by the University of Pisa. To achieve our objectives, we identified 10 permanent transects visited once a month for an entire vegetative year with the aim of monitoring the presence and abundance of annual plant species. Each 20 m long transect was randomly selected to ensure homogeneity and representativeness of the study area. Within each transect we annotated environmental characteristics (distance from the sea, altitude, disturbance) and selected ten plots of 0.25 m2 each to quantify plant community composition. For each species we gathered information concerning the following vegetative and reproductive traits that likely influence plant responses to climate conditions: plant height, SLA, LDMC, seed mass and seed dormancy class, as well as seed dispersal and pollination strategy. In September 2020, no annual plants were detected in any plot. The first seedling emergences occurred in the first half of October soon after the early autumn rains. These seedlings belong to Festuca fasciculata Forssk., Marcus-Kochia ramosissima (Desf.) Al-Shehbaz, Medicago littoralis Rhode ex Loisel. and Lagurus ovatus L., which also dominated the communities throughout the year until the end of the vegetative and reproductive phases (July). During the autumn and winter months other frequently occurring species were Cerastium ligusticum Viv. and Draba verna L., which completely disappeared when spring temperatures raised, while M. ramosissima increased its coverage. An even different pattern characterizes Odontites luteus (L.) Clairv., detected since mid-autumn but its frequencies decreased in the winter months, increased in early spring and then decreased again. Catapodium balearicum (Willk.) H. Scholz was instead observed only in May. By using a comprehensive multivariate approach, considering plant co-occurrences and their vegetative and reproductive traits, we will be able to evaluate covariances and trade-offs explaining plant responses to interannual variations in climatic conditions. Specifically, we expect to track phenology and composition of the communities and to understand annual plant species responses to extreme climatic events.
2021
978-88-85915-26-8
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11568/1121518
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus ND
  • ???jsp.display-item.citation.isi??? ND
social impact