SciCombinator

Discover the most talked about and latest scientific content & concepts.

Concept: Oak

170

Edge effects represent an inevitable and important consequence of habitat loss and fragmentation. These effects include changes in microclimate, solar radiation, or temperature. Such abiotic effects can, in turn, impact biotic factors. They can have a substantial impact on species, communities, and ecosystems. Here we examine clinal variations in stable carbon and nitrogen isotope values for trees along an edge-interior gradient in the dry deciduous forest at Ankarafantsika National Park. We predicted that soil respiration and differences in solar irradiance would result in stratified δ(13)C values where leaves collected close to the forest floor would have lower δ(13)C values than those growing higher up in the canopy. We also anticipated that plants growing at the savannah-forest boundary would have higher δ(13)C and δ(15)N values than plants growing in the forest interior. As expected, we detected a small but significant canopy effect. Leaves growing below 2 m from the forest floor exhibit δ(13)C values that are, on average, 1.1‰ lower than those growing above this threshold. We did not, however, find any relationship between foliar δ(13)C and distance from the edge. Unpredictably, we detected a striking positive relationship between foliar δ(15)N values and increasing distance into the forest interior. Variability in physiology among species, anthropogenic influence, organic input, and rooting depth cannot adequately explain this trend. Instead, this unexpected relationship most likely reflects decreasing nutrient or water availability, or a shift in N-sources with increasing distance from the savannah. Unlike most forest communities, the trees at Ampijoroa are growing in nutrient-limited sands. In addition to being nutrient poor, these well-drained soils likely decrease the amount of soil water available to forest vegetation. Continued research on plant responses to edge effects will improve our understanding of the conservation biology of forest ecosystems in Madagascar.

Concepts: Plant, Ecology, Soil, Ecosystem, Biome, Oak, Deciduous, Tropical and subtropical dry broadleaf forests

164

Apolygus lucorum (Meyer-Dür) (Hemiptera: Miridae) is one of the most important herbivores in a broad range of cultivated plants, including cotton, cereals, vegetables, and fruit crops in China. In this manuscript, we report on a 6-year long study in which (adult) A. lucorum abundance was recorded on 174 plant species from 39 families from early July to mid-September. Through the study period per year, the proportion of flowering plants exploited by adult A. lucorum was significantly greater than that of non-flowering plants. For a given plant species, A. lucorum adults reached peak abundance at the flowering stage, when the plant had the greatest attraction to the adults. More specifically, mean adult abundance on 26 species of major host plants and their relative standard attraction were 10.3-28.9 times and 9.3-19.5 times higher at flowering stage than during non-flowering periods, respectively. Among all the tested species, A. lucorum adults switched food plants according to the succession of flowering plant species. In early July, A. lucorum adults preferred some plant species in bloom, such as Vigna radiata, Gossypium hirsutum, Helianthus annuus and Chrysanthemum coronarium; since late July, adults dispersed into other flowering hosts (e.g. Ricinus communis, Impatiens balsamina, Humulus scandens, Ocimum basilicum, Agastache rugosus and Coriandrum sativum); in early September, they largely migrated to flowering Artemisia spp. (e.g. A. argyi, A. lavandulaefolia, A. annua and A. scoparia). Our findings underscore the important role of flowering plays in the population dynamics and inter-plant migration of this mirid bug. Also, our work helps understand evolutionary aspects of host plant use in polyphagous insects such as A. lucorum, and provides baseline information for the development of sustainable management strategies of this key agricultural pest.

Concepts: Plant, Annual plant, Fern, Euphorbiaceae, Flowering plant, Flower, Oak, Heteroptera

143

This supplement registry study evaluated the effect of supplementation with Robuvit® on the burnout syndrome (BOS) of patients with significant fatigue and high oxidative stress. Robuvit® (French oak wood extract) is a standardized supplement, effective in treating chronic fatigue syndrome (CFS), post-traumatic stress disorder (PTSD) and convalescence.

Concepts: Oxidative stress, Complex post-traumatic stress disorder, Cognitive behavioral therapy, Posttraumatic stress disorder, Stress, Chronic fatigue syndrome, Oak

100

The ecological impact of night-time lighting is of concern because of its well-demonstrated effects on animal behaviour. However, the potential of light pollution to change plant phenology and its corresponding knock-on effects on associated herbivores are less clear. Here, we test if artificial lighting can advance the timing of budburst in trees. We took a UK-wide 13 year dataset of spatially referenced budburst data from four deciduous tree species and matched it with both satellite imagery of night-time lighting and average spring temperature. We find that budburst occurs up to 7.5 days earlier in brighter areas, with the relationship being more pronounced for later-budding species. Excluding large urban areas from the analysis showed an even more pronounced advance of budburst, confirming that the urban ‘heat-island’ effect is not the sole cause of earlier urban budburst. Similarly, the advance in budburst across all sites is too large to be explained by increases in temperature alone. This dramatic advance of budburst illustrates the need for further experimental investigation into the impact of artificial night-time lighting on plant phenology and subsequent species interactions. As light pollution is a growing global phenomenon, the findings of this study are likely to be applicable to a wide range of species interactions across the world.

Concepts: Biology, Plant, Ecology, Urban area, Tree, Lighting, Oak, Deciduous

30

The phenology of growth in temperate deciduous forests, including the timing of leaf emergence and senescence, has strong control over ecosystem properties such as productivity and nutrient cycling, and has an important role in the carbon economy of understory plants. Extended leaf phenology, whereby understory species assimilate carbon in early spring before canopy closure or in late autumn after canopy fall, has been identified as a key feature of many forest species invasions, but it remains unclear whether there are systematic differences in the growth phenology of native and invasive forest species or whether invaders are more responsive to warming trends that have lengthened the duration of spring or autumn growth. Here, in a 3-year monitoring study of 43 native and 30 non-native shrub and liana species common to deciduous forests in the eastern United States, I show that extended autumn leaf phenology is a common attribute of eastern US forest invasions, where non-native species are extending the autumn growing season by an average of 4 weeks compared with natives. In contrast, there was no consistent evidence that non-natives as a group show earlier spring growth phenology, and non-natives were not better able to track interannual variation in spring temperatures. Seasonal leaf production and photosynthetic data suggest that most non-native species capture a significant proportion of their annual carbon assimilate after canopy leaf fall, a behaviour that was virtually absent in natives and consistent across five phylogenetic groups. Pronounced differences in how native and non-native understory species use pre- and post-canopy environments suggest eastern US invaders are driving a seasonal redistribution of forest productivity that may rival climate change in its impact on forest processes.

Concepts: Plant, Temperate broadleaf and mixed forests, Season, Leaf, Abscission, Invasive species, Oak, Deciduous

28

The butanol-HCl spectrophotometric assay is widely used for quantifying extractable and insoluble condensed tannins (CT, syn. proanthocyanidins) in foods, feeds, and foliage of herbaceous and woody plants, but the method underestimates total CT content when applied directly to plant material. To improve CT quantitation, we tested various cosolvents with butanol-HCl and found that acetone increased anthocyanidin yields from two forage Lotus species having contrasting procyanidin and prodelphinidin compositions. A butanol-HCl-iron assay run with 50% (v/v) acetone gave linear responses with Lotus CT standards and increased estimates of total CT in Lotus herbage and leaves by up to 3.2-fold over the conventional method run without acetone. The use of thiolysis to determine the purity of CT standards further improved quantitation. Gel-state 13C and 1H-13C HSQC NMR spectra of insoluble residues collected after butanol-HCl assays revealed that acetone increased anthocyanidin yields by facilitating complete solubilization of CT from tissue.

Concepts: Plant, Fern, Leaf, Enzyme assay, Tannin, Proanthocyanidin, Oak, Vascular tissue

28

The discovery of plant polyphenols in food is perhaps one of the biggest breakthroughs in modern food science. Plant polyphenols are known for their role in food quality and safety, since they contribute significantly to taste, flavour, colour, stability etc., while they are increasingly recognised as important factors in long-term health, contributing towards reducing the risk of chronic disease. Almost 200years ago, hydrolyzable tannins (HTs) were the first group of plant polyphenols subjected to analytical chemical research. Despite the lack of commercially available standards, food analysis research offers a wealth of papers dealing with extraction optimisation, identification and quantification of HTs. The object of this review is to summarise analytical chemistry applications and the tools currently used for the analysis of HTs in food.

Concepts: Nutrition, Plant, Catechin, Tannin, Polyphenol, Oak, Tannic acid

28

After an initial survey on feeds and feeding practices at Kumaon Himalaya, the potential of oak leaves feeding was evaluated in six native heifers (Bos indicus; 101.5 kg BW, 18-24 months) in a partial switch-over design involving two animals each on each treatment at a time. The feeding treatments involved high and low levels of oak leaves (Quercus leucotrichophora, oak leaves (OL)) supplemented to local mixed grass hay (GH) which were GH (G1), GH + low level (42.5 %) of OL (G2) and GH + high level (63.6 %) of OL (G3). The feeding trial for each treatment was conducted for 40 days that ended with a digestibility trial of 6-day duration. The dry matter (DM) intake (kg/day) was non-significantly higher in G3 (3.52) than G2 (3.11) and G1 (2.96). Intake of crude protein (CP) (g/day) was significantly (P < 0.001) higher in both G2 and G3 than G1. The digestibility of DM, CP, organic matter, ether extract and total carbohydrates increased (P < 0.001) linearly in OL-fed groups as compared to control. The total digestible nutrients (TDN) (kg/day) intake was significantly higher (P < 0.05) in G3 compared to G1, but it was comparable between G1 and G2. Intake of DM, CP, digestible CP (DCP) and TDN/metabolizable energy (ME) per kilogram metabolic body weight was significantly higher (P < 0.01) in G3 than G2 which in turn was also higher (P < 0.01) than G1. The animals under G1 had negative gain (-50 g/day) compared to 146 and 306 g/day in G2 and G3, respectively. Feeding of OL reduced serum urea and creatinine level and supported serum protein concentration better in G3 compared to G2. The feeding of cattle on GH alone was lacking in both energy and protein for sustaining minimum levels of production, whereas in combination with OL at 36.4:63.6 ratios supported minimum level of production (ADG 300 g) with near nutritional adequacy for major nutrients (CP, DCP, TDN, ME) but with a caution for the minor nutrients like calcium and phosphorus that need to be supplemented.

Concepts: Protein, Metabolism, Nutrition, Animal, Nitrogen, Digestion, Serum total protein, Oak

27

Wine aging is an important process to produce high-quality wines. Traditionally, wines are aged in oak barrel aging systems. However, due to the disadvantages of the traditional aging technology, such as lengthy time needed, high cost, etc., innovative aging technologies have been developed. These technologies involve aging wines using wood fragments, application of micro-oxygenation, aging on lees, or application of some physical methods. Moreover, wine bottling can be regarded as the second phase of wine aging and is essential for most wines. Each technology can benefit the aging process from different aspects. Traditional oak barrel aging technology is the oldest and widely accepted technology. The application of wood fragments and physical methods are promising in accelerating aging process artificially, while application of micro-oxygenation and lees is reliable to improve wine quality. This paper reviews recent developments of the wine aging technologies. The impacts of operational parameters of each technology on wine quality during aging are analyzed, and comparisons among these aging technologies are made. In addition, several strategies to produce high-quality wines in a short aging period are also proposed.

Concepts: Wine, Oenology, Fermentation, Cabernet Sauvignon, Oak, Chardonnay, Sangiovese, Chilean wine

27

Chemical profiles of anthocyanin and non-anthocyanin phenolics of Cabernet Sauvignon wine made by two different winemaking techniques (traditional vinification and Ganimede method) were determined by high performance liquid chromatography-mass spectrometry (HPLC-MS). Particularly, effect of extraction on and subsequent stability of the phenolic compounds from the end of fermentation to bottling were investigated. The results showed that the total anthocyanin content was higher in the young wines produced in the Ganimede fermenter. The anthocyanin contents in these wines subsequently decreased significantly after two years of ageing. By contrast, the traditional vinification was slightly better than the Ganimede to yield the non-anthocyanin phenolics. This indicates that the Ganimede fermenter might be suitable for the production of brightly coloured red wines for early consumption, which could save time and labour cost for industrial production of highquality wines.

Concepts: Yeast, Wine, Oenology, Fermentation, Cabernet Sauvignon, Oak, Winemaking, Chilean wine