Abstract Detail

Ecological Section

Mears, Marietta [1], Asahl, Derick [2], Downing, Lyndsey [1], Skornia, Erin [3], Stephan, Kirsten [4].

Germination rates of Callirhoe bushii and Lespedeza cuneata under future climate conditions in Missouri.

Climate change, comprising changes in temperature and precipitation regime, may cause the extirpation of native species highly adapted to their current habitat and may cause the proliferation of invasive plant species tolerant of a wide range of environmental conditions. In this study we compared how modeled future climatic conditions in Missouri affected germination and initial growth rates for native Callirhoe bushii (Bush’s poppy mallow), a species of conservation concern, and invasive Lespedeza cuneata (sericea lespedeza). Average maximum temperature and total precipitation during germination (March) were obtained for the years 2081 to 2100 (future climate) and 1961 to 1990 (baseline climate) using online climate tools developed by The Nature Conservancy. Growth chambers were used to simulate these different climatic conditions: Baseline climate (13ºC, 91 mm precipitation, 12 wet days), Future (F1) climate with even moisture (21ºC, 91 mm precipitation, 8 wet days), and Future (F2) climate with downpour and drought (precipitation applied on 2 wet days). After four weeks, germination rate and seedling mass were assessed by counting and weighing seedlings that had emerged from the 200 seeds that had been sown into each of five planting trays per treatment per species. C. bushii had significantly (P<0.05) higher germination under baseline climate (56 seedlings) than either future climate (F1: 20 seedlings, F2: 37 seedlings) condition, potentially making this species more susceptible to local extinction in the future. Germination of L. cuneata (on average 39 seedlings) did not differ between climate conditions. Seedlings of C. bushii were larger in future climates (F1: 5.5, F2: 6.1 mg/seedling) than in baseline climate (2.4 mg/seedling) (P<0.05). Presumably, once germinated, higher temperatures of the future climate promoted seedling growth. If this resulted in higher survival rates to maturity, it could offset lower germination rates under future climate. Seedlings of L. cuneata were smaller (P<0.05) under Future-with-Drought/Flood (F2) conditions (0.49 mg/seedling) than under Baseline (0.82 mg/seedling) or Future-without-Drought (F1) (0.77 mg/seedling) conditions, indicating that L. cuneata seedlings may be sensitive to the moisture regime. Loss of biodiversity, attributed primarily to habitat loss and secondarily to invasive plants, could be exacerbated by a decline in germination rate of C. bushii, and potentially other of native species, under future climate conditions. Thus, in the light of climate change, protection of existing habitats is imperative to the conservation of C. bushii along with intensified eradication efforts of L. cuneata.

1 - Lincoln University, Life and Physical Sciences, 816 Chestnut St, Jefferson City, MO, 65101, USA
2 - Lincoln University, Agriculture and Environmental Sciences , 820 Chestnut St, Jefferson City, MO, 65101, USA
3 - Lincoln University, Life and Physical Sciences, 820 Chestnut St, Jefferson City, MO, 65101, USA
4 - Lincoln University, Life and Physical Sciences, 816 Chestnut Sst, Jefferson City, MO, 65101, USA

Keywords:
climate change
native
invasive
germination percentage
seedling mass.

Presentation Type: Poster:Posters for Sections
Session: P
Location: Hall D/The Shaw Conference Centre
Date: Monday, July 27th, 2015
Time: 5:30 PM
Number: PEC024
Abstract ID:289
Candidate for Awards:Ecological Section Best Undergraduate Presentation Award