Microbial Community of Saline, Alkaline Lakes in the Nebraska Sandhills Based on 16S rRNA Gene Amplicon Sequence Data

The Nebraska Sandhills region contains over 1,500 geochemically diverse interdunal lakes, some of which are potassium rich, alkaline, and hypersaline. Here, we report 16S rRNA amplicon pyrosequencing data on the water and sediment microbial communities of eight alkaline lakes in the Sandhills of western Nebraska.

A new species of Oecetis McLachlan (Trichoptera, Leptoceridae) from the Sandhills region of South Carolina, USA

A new species Oecetis McLachlan, O. psammophila sp. nov., is described from the Sandhills ecoregion of South Carolina. Illustrations of male and female genitalia and wing photographs are provided. Following the classification of Chen (1993), O. psammophila belongs to the O. parva Species-group of the subgenus Pseudosetodes Ulmer. Adult specimens were taken at ultraviolet lights near or immediately adjacent to impounded streams or spring-fed wetlands. The larva remains unknown, but other Nearctic members of the O. parva Species-group inhabit lentic habitats.

Within-stand variation in understorey vegetation affects fire behaviour in longleaf pine xeric sandhills

The frequent fires typical of the longleaf pine ecosystem in the south-eastern USA are carried by live understorey vegetation and pine litter. Mature longleaf pine stands in the xeric sandhills region have a variable understorey vegetation layer, creating several fuel complexes at the within-stand scale (20 m2). We identified three fuel complexes found in frequently burned stands on the Carolina Sandhills National Wildlife Refuge, and used prescribed fire to test whether distinct sets of fire conditions were associated with each fuel complex. Study plots were dominated by either turkey oak or wiregrass in the understorey, or lacked understorey vegetation and contained only longleaf pine litter. Turkey oak-dominated plots had the highest fuel loads, and during burns they had higher total net heat flux than wiregrass- or longleaf pine litter-dominated plots, and longer burn durations than wiregrass-dominated plots. Across all plots, the quantity of litter fragments had the greatest effect on fire temperature and duration of burn. These results show that the patchy understorey vegetation within longleaf pine stands will create heterogeneous fires, and areas dominated by turkey oak may have increased fire intensity and soil heating compared with the other two fuel complexes.

490 Toward Conserving a Threatened Orchid (Platanthera praeclara)

Platanthera praeclara, commonly called western prairie fringed orchid, is a showy forb native to seven states and one Canadian province. The species had resisted previous attempts at propagation. Small, isolated populations in the sandhills region of western Nebraska are disjunct and visitation by natural pollen vectors appears to be in decline. Modern cultivation practices and other habitat encroachment factors, including urban development, recreational activities, and natural fluctuations in seasonal water availability all have the potential to exert pressure on current populations. Federal and state permits have allowed a limited hand-pollination study to be conducted on federal land. Hand-pollinated plants showed a greater fruit production compared to control plants receiving no human pollination assistance. Germination studies were conducted using aseptic in vitro techniques. The microscopic seeds possess testa that are extremely hard and resistant to liquid absorption, which presents challenges to germination in vitro. These challenges will be discussed. Alternating cold treatments with room temperatures appeared necessary to promote protocorm development after germination. Three media tested produced varying germination responses. Juvenile plants produced through micropropagation can offer propagules for possible future reintroduction efforts of this protected species.