Local grassland restoration affects insect communities

1. It is hypothesised that ecological restoration in grasslands can induce an alternative stable state shift in vegetation. The change in vegetation influences insect community assemblages and allows for greater functional redundancy in pollination and refuge for native insect species. 2. Insect community assemblages at eight coastal California grassland sites were evaluated. Half of these sites had undergone restoration through active revegetation of native grassland flora and half were non‐restored. Insects were collected from Lupinus bicolor (Fabaceae) within 2 × 2‐m² plots in spring 2017. Lupinus bicolor is a common native species that is used in California restoration projects, and home and state landscaping projects. 3. Ordination demonstrated that insect community assemblages were different between restored and non‐restored sites. These differences were seen in insect functional groups as well as taxa‐specific differences and were found to be driven by environmental characteristics such as non‐native forb cover. 4. Functional redundancy of herbivores decreased at restored sites, while pollinators became more redundant compared with non‐restored sites. The assemblages of the common species found at restoration sites contained more native insects than those found at non‐restored sites, including species such as Bombus vosnesenskii. 5. Local grassland restoration has the potential to induce an alternative stable state change and affect insect community assemblages. Additionally, it was found that grassland restoration can be a potential conservation tool to provide refugia for bumblebees (Bombus), but additional studies are required to fully understand its broader applicability.     

Antiplasmodial activity of Artemisia annua plant cell cultures

Extracts of Artemisia annua cultures have been assessed for in vitro activity against the malarial parasite Plasmodium falciparum. Callus and suspension cells and medium were analysed and examined for their activity at different stages of growth and development. Time-course experiments were carried out to investigate the influence of various basal media, plant growth regulators and light on both growth and possible artemisinin production. Two active fractions were obtained but artemisinin was not detected.     

Map analysis of ligand binding to a linear lattice

A one-dimensional mapping of the binding properties of a linear lattice offers an exact analytical solution for the site-specific properties of the lattice once the length N and the parameter for nearest neighbor interactions are specified. The solution is derived independent of the definition of the partition function or the transfer matrix, nor does it involve combinatorial arguments. This result provides a simple and effective way of analyzing experimental data for protein-ligand interactions and broadens our understanding of site-specific properties in biological macromolecules.     

Enchytraeid numbers,biomass and respiratory metabolism in a beech woodland - Wytham Woods,Oxford

Summary The mean annual population density of enchytraeids in the litter and upper 6 cm of soil was found to be 14,590 m^-2. Mean individual weights approximated 116, 158 and 151 g wet wt. in the litter, 0–3 cm and 3–6 cm strata respectively. The mean biomass was estimated to be 1.908 g wet wt m^-2. Vertical migration was shown to occur, the upward migration in late Autumn was a response to temperatures in the litter being temporarily higher than those of the 0–3 cm stratum. As a result of upward vertical migration and possibly recruitment, numbers reached a maximum in the litter during Winter. On an annual basis the litter, 0–3 and 3–6 cm strata contained 41.43, 46.44 and 12.12% respectively of the extracted enchytraeids. The equivalent biomass values were 33.18, 52.46 and 14.36%. Total numbers and biomass revealed a general picture of high values in late Autumn to Winter which gradually decreased through Spring and Summer except for a minor peak in May–June. The annual oxygen consumption of the enchytraeids approximated 4.285 l O₂ m^-2 yr^-1 (20.461 kcal85.610 kJ) and accounted for 1.63% of the total soil metabolism. A production/biomass (P/B) ratio of 4.93 was estimated as was a net population efficiency of 32%. For this site the contribution by enchytraeids to total soil respiration is about one-third that of the earthworms and an order of magnitude greater than that of the nematodes.     

Alkaloids of Uncaria attenuata from Thailand

The major alkaloids of a sample of leaves of Uncaria attenuata obtained from Thailand have been identified as the pentacyclic heteroyohimbine alkaloids tetrahydroalstonine, rauniticine and the novel 14-β-hydroxy-3-iso-rauniticine. Evidence for the structure of the new alkaloid was obtained from a study of UV, IR, MS, ¹H NMR and ¹C NMR spectra.     

Burrowing,feeding, egestion and energy budgets of Allolobophora rosea (Savigny) (Lumbricidae)

Summary Allolobophora rosea (Savigny) was found to be common in mull type soils beneath bramble (Rubus fruticosus L.). Burrow construction in this soil type in the laboratory at 4.4, 10.0 and 14.8°C ranged between 133 and 516 mm g^-1 fresh wt of worm day^-1. Burrowing was affected by both body size and temperature. Rates of soil displacement during burrowing were estimated from burrowing rates, burrow dimensions and soil density; depending on body size and temperature they were in the range 809–1,928 mg dry wt of soil g^-1 fresh wt of worm day^-1. These values were in reasonable agreement with measured egestion rates (range: 1,000–2,000 mg dry wt of egesta g^-1 fresh wt of worm day^-1). It was concluded that A. rosea eats its way through the soil and is adapted to its rapid turnover. Gut turnover times were calculated to be between 1 and 2.5 h.Direct observation indicated that feeding was by a grazing procedure and it was shown that A. rosea preferentially selects the more organic fractions of the soil for ingestion.The evaluation of energy budgets for individual small immature, large immature and adult worms at 10°C revealed respiration to production ratios (R/P) of 1.0, 1.8 and 4.1, respectively. Assimilation efficiencies (A/C) were always less than 2.5%.