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This study was carried out to evaluate the use of tannin extract from Acacia mearnsii as a strategy to reduce methane (CH4) in two distinct cattle genotypes and its effect on intake, digestibility, microbial efficiency and ruminal fermentation. Four Nellore (Bos indicus) and four Holstein (Bos taurus) dry cows fitted with rumen cannula were assigned to two 4 × 4 Latin square design, in a 2 × 4 factorial arrangement, where each genotype represented a square receiving four tannin levels (commercial extract of A. mearnsii) in the diet (0%, 0.5%, 1.0% and 1.5% of dry matter). Tannin levels used did not cause a reduction in feed intake or rumen passage rate for both genotypes (p > 0.05), although there was a linear reduction in the degradation rate and ruminal disappearance of diet (p < 0.05). The increase in tannin levels reduced the amount of entodiniomorph protozoa in the Nellore cattle (p < 0.05). There was no change in N retention or microbial efficiency (p > 0.05), despite the linear reduction of nutrient digestibility and the synthesis of microbial nitrogen (p < 0.05). The ruminal CH4 production was reduced (p < 0.05) without reducing the short‐chain fatty acid production. The threshold of 0.72% of tannin in the diet was estimated as the starting point for the reduction of ruminal CH4 production with long‐term efficacy. Therefore, the use of low levels of tannin extract from A. mearnsii is a potential option to manipulate rumen fermentation in Nellore and Holstein cattle and needs to be further investigated. [ABSTRACT FROM AUTHOR]

The outcomes of ecosystem restoration projects should be periodically monitored to inform subsequent adaptive management decisions. In 2012, a project was begun to remove both invasive alien plants and fish from the Rondegat River in South Africa. Although the initial post-intervention dynamics of aquatic fauna have been documented, the results of the simultaneous clearing of dense riparian stands of alien trees and shrubs have not been reported. We examined native riparian vegetation recovery over 3 years after alien plant clearing. We documented increased cover of native riparian shrubs, but a simultaneous increase of alien and native weedy grass cover. Secondary invasions, especially by grasses, can have strong effects on ecosystem dynamics and achieving the goals of restoration may therefore require additional active management. Our findings provide an initial baseline reference for future monitoring and adaptive management decisions. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine selected surface properties of varnished beech wood impregnated with natural extracts after exposure to accelerated weathering. Beech wood samples were impregnated with aqueous solutions of 5 and 10% mimosa ( Acacia mollissima) and quebracho ( Shinopsis lorentzii) tannins. After weathering, colour changes (Δ L*, Δ a*, Δ b*, and Δ E*) in addition to scratch resistance and surface hardness values were calculated and evaluated. As a result of the weathering process, greater colour changes (Δ E*) were detected in the beech wood samples impregnated with tannins compared with the unimpregnated control samples. The least colour change occurred in the Tanalith-E-impregnated samples. Total colour change was adversely affected with tannin impregnation after the weathering processes. In terms of surface hardness and scratch resistance, the highest values were observed in the mimosa-solution-impregnated and control samples. Furthermore, it was found that scratch resistance and hardness values tended to increase during the first period of weathering and decreased thereafter. Regarding surface properties, the best results were obtained when polyurethane varnish was employed compared with the other varnish types. [ABSTRACT FROM AUTHOR]

The aim of the present study was to compare the in vitro inhibitory effects on the salivary and pancreatic α-amylases and the in vivo hypoglycemic actions of the hydrolysable tannin from Chinese natural gall and the condensed tannin from Acacia mearnsii. The human salivary α-amylase was more strongly inhibited by the hydrolysable than by the condensed tannin, with the concentrations for 50% inhibition (IC50) being 47.0 and 285.4 μM, respectively. The inhibitory capacities of both tannins on the pancreatic α-amylase were also different, with IC50 values being 141.1 μM for the hydrolysable tannin and 248.1 μM for the condensed tannin. The kinetics of the inhibition presented complex patterns in that for both inhibitors more than one molecule can bind simultaneously to either the free enzyme of the substrate-complexed enzyme (parabolic mixed inhibition). Both tannins were able to inhibit the intestinal starch absorption. Inhibition by the hydrolysable tannin was concentration-dependent, with 53% inhibition at the dose of 58.8 μmol/kg and 88% inhibition at the dose of 294 μmol/kg. For the condensed tannin, inhibition was not substantially different for doses between 124.4 μmol/kg (49%) and 620 μmol/kg (57%). It can be concluded that both tannins, but especially the hydrolysable one, could be useful in controlling the postprandial glycemic levels in diabetes. [ABSTRACT FROM AUTHOR]

Ceratocystis albifundus is the most important fungal pathogen of black wattle ( Acacia mearnsii) grown in plantations in southern and eastern Africa. It is a homothallic fungus but also undergoes unidirectional mating type switching. As a result, the ascospore progeny can be either self-fertile or self-sterile. The only apparent difference between these mating types is the deletion of the MAT1-2-1 gene in self-sterile isolates. There is some evidence suggesting that self-sterile isolates grow more slowly than self-fertile isolates, but this has not been tested rigorously. The aim of this study was to determine whether self-sterile isolates are less fit by examining growth rate, relative germination rate and pathogenicity. Five self-sterile isolates were generated from each of five self-fertile isolates of C. albifundus and these 30 isolates were compared. The results showed that the self-sterile isolates grew consistently slower and were less pathogenic than the self-fertile isolates. The germination ratio of self-fertile to self-sterile isolates from single ascospores collected from the ascomata of five self-fertile isolates was on average 7:3. This could be a consequence of the self-sterile isolates having a lower germination rate. This observation, and the lower growth and pathogenicity levels, suggests that self-sterile isolates are not likely to compete effectively in nature, raising intriguing questions regarding their role and value to C. albifundus and other fungi having a similar mating system. [ABSTRACT FROM AUTHOR]

The relationship between species richness and productivity is important from both a basic, theoretical perspective and also because it has important ramifications for applied ecology including ecosystem restoration and the design of carbon offset plantings. While a more species-rich community is often believed to be more productive than a species-poor community, findings from observational and experimental studies differ and our understanding of the relationship comes largely from grasslands. Consequently, we aimed to determine for the first time the nature of the species richness-productivity relationship in a southern-hemisphere dry sclerophyll ecosystem. We investigated the impact of species richness on productivity, plant density and mean plant biomass at three sowing densities in three species assemblages. E ucalyptus globulus, A cacia mearnsii and A llocasuarina verticillata were each grown as monocultures and included in every subsequent level of species richness, forming three distinct species assemblages. Communities were grown in a glasshouse pot experiment for four months, then harvested and above-ground biomass measured. We found no general species richness-productivity relationship in the communities studied. There were no overall increases in productivity as species richness increased and in fact in most cases the productivity of communities with 4 and 8 species was lower than monocultures of the dominants. Importantly, density influenced the way richness affected productivity and this effect was dependent upon assemblage, indicating that species identity is a key determinant of productivity. These results demonstrate important ecological principles in a previously untested system. A key outcome of this experiment is that density alters the relationship between species richness and initial productivity in assemblages of Australian dry sclerophyll species. [ABSTRACT FROM AUTHOR]

This paper reports an investigation into the use of condensed black wattle tannin as an environmental friendly sealer after zinc phosphating of carbon steel. In order to verify the sealer efficiency against corrosion, electrochemical impedance spectroscopy, potentiodynamic polarisation and salt spray tests were performed. To verify the pore modifications and phase compositions, SEM, electron dispersive spectroscopy and X-ray diffraction analysis were carried out. The influence of the sealer on the adherence of finishing coatings was analysed. The results show that the tannin/sealer did not affect the final coating adhesion and improved the corrosion resistance of sealed samples. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A field mesocosm experiment was conducted at the Three Gorges Reservoir to investigate the utility of black wattle extract in controlling blue algal blooms. The mesocosm experiment was divided into two parts: (1) a short-term test to evaluate how black wattle extract inhibits algal blooms in an emergency and (2) a long-term test to evaluate how black wattle extract maintains water quality and prevents algal blooms over a 1-year period. In the short-term test, the results showed that 3 to 4 mg L-1 black wattle extract could reduce algal biomass in 1 week, whereas serious algal blooms occurred in the untreated control mesocosm. More importandy, the long-term test suggested that black wattie extract played a significant role in plankton structure optimization at lower concentrations of 1 to 2 mg L-1. In this test, phytoplankton diversity increased, with the dominant species shifting from cyanobacteria to diatoms and other algae. Meanwhile, as water quality improved through the presence of plant extract treatment, the numbers of smaller Zooplankton decreased and larger species increased. Therefore, this investigation founded a novel nature plant agent that not only has good effects on algal bloom control, but also restores the aquatic ecosystem. [ABSTRACT FROM AUTHOR]

ABSTRACT Concerns exist over increasing sediment yields in areas of South Africa with a Mediterranean climate that result from the clearing of invasive woody vegetation from steep slopes, as part of the Working for Water Programme. Erosion rates were monitored with erosion pins over a 26-month period. Measurements were made on slopes covered with indigenous fynbos vegetation, intact Acacia mearnsii stands (the invasive species) and on slopes from which A. mearnsii had been cleared either within the last 2 years or 11 years ago. Net erosion was observed at all sites following the largest storm during the monitoring period, whereas smaller storms were often accompanied by net deposition. Cleared locations showed the most variable response through time and sites with native fynbos vegetation the least. A stepwise multiple regression showed that vegetation cover, slope gradient and stone cover were the main variables affecting soil loss, but the relationship varied between sites and measuring periods. Soil loss was negatively related to vegetation cover and stone cover, as could be expected; the negative relationship with slope was more surprising. Stone cover, which increases with slope gradient, is considered to be an important control on soil loss. The findings of this study suggest that the rehabilitation of hillslopes invaded by alien woody vegetation needs to take into account the slow recovery of vegetation after initial clearing as, 11 years since clearing, significant erosion still occurs during severe storms. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A new coagulant obtained through the polymerisation of Acacia mearnsii de Wild. tannin extract has been characterised in the removal of a dangerous dye pollutant: Erioglaucine (also called Acid Blue 9 or FD&C Blue 1). This coagulant was laboratory synthesised according to the etherification of tannins using glycidyltrimethylammonium chloride and formaldehyde and its performance in dye removal in terms of efficiency was high. Reasonably low coagulant dosages ( ca. 50 mg l−1) reach high capacity levels (approximately 0.7 mg dye mg−1 of coagulant) and pH and temperature are not extremely affecting variables. A design of experiments using response surface methodology led to the evaluation of the influence of parameters such as coagulant dosage and initial dye concentration, and reliable data were collected in order to maximise the removal capacity. The whole coagulant-dye system was successfully modelled by applying the Langmuir hypothesis. Parameters qmax and b were obtained with an adjusted correlation factor ( r2) above 0.8. [ABSTRACT FROM AUTHOR]

In order to reduce the environmental impacts caused by chemical substances harmful to the environment and human health, the black wattle tannin can be used as an environmentally friendly corrosion inhibitor in acid and near neutral media. This paper provides information on the application of black wattle tannin as an inhibitor against the corrosion of carbon steel. The inhibition was evaluated using potentiodynamic polarization (PP) and electrochemical impedance spectroscopy (EIS) at room temperature in aerated 0.1mol L-1 Na2SO4 (pH 6.0 and 2.5). The black wattle tannin when used as a corrosion inhibitor is more effective at acidic pH, its efficiency being dependent on its concentration. At the higher pH value (pH 6.0), a blue-black film (ferric tannate) with a short-term protection against corrosion was formed in aerated aqueous solution. At pH 2.5, this blue-black film was not observed. [ABSTRACT FROM AUTHOR]

It is well known that species of Ceratocystis, which cause canker and wilt diseases on trees, require wounds for infection. In this regard, a number of physical and environmental factors influence the success of wound colonization by these fungi. The aim of this study was to consider the influence of wound age, stem diameter and colonization of wounds by Ophiostoma quercus on the success of infection by Ceratocystis albifundus, an important wilt pathogen of Acacia mearnsii in southern and eastern Africa, under field conditions. This was performed by doing controlled inoculations on Acacia mearnsii trees, of different diameters, with C. albifundus at different time intervals after wounding and after pre-inoculation of wounds with O. quercus at the time of wounding. The success of infection by C. albifundus decreased significantly from 8 h after wounding and was higher on stems of greater diameter. Pre-infection of wounds by O. quercus reduced the infection success of C. albifundus. The overall results showed that managing wounds created during forestry operations by treating wounds with naturally occurring, non-virulent fungi, such as O. quercus, could reduce the prevalence of infections by C. albifundus. [ABSTRACT FROM AUTHOR]

There is need for documenting the long-term effects of plant invasions at the landscape scale. We investigated the possible catalytic effect of invasive Acacia mearnsii De Wild. on the colonization of rural landscapes by native plant species on Réunion Island (Mascarene Archipelago, Indian Ocean). Data were recorded from 182 circular plots of 50 m2 within a set of 48 large invasion patches, aged from 1 to 48+ years. Only eighteen native plant species were present in the invaded patches and these in only 21 of the 48 patches. The Acacia invasion patches colonized by native flora were older and closer to the closest forest remnant. Most invasion patches colonized by native species were located <200 m from forest remnants. Results are consistent with studies on colonization rates of nonindigenous forest plantations, which increase with age and decrease with distance to seeds sources. Yet, the rate of Acacia invasion patches colonized by native flora remained very low compared to studies on the colonization of exotic plantations in other tropical countries. We conclude that invasion patches of Acacia mearnsii are poor colonizing sites for native plant species. Allelopathy is suspected as one of the strongest factors, which prevent this colonization. [ABSTRACT FROM AUTHOR]

The article offers information on a study which examined the inhibitory effect of Acacia mollissima or wattle and Terminalia chebula or myrobalan on the action of collagenase against collagen. A review of the related literature is given. The kinetics of the inhibition of collagenase by wattle and myrobalan was derived from the scope of hydrolysis of 2-furanacryloyl-L-leucyl-glycyl-L-prolyl-L-alanine. It discusses in detail the research findings.

As part of an eradication program, field searches were conducted to verify the geographical extent of the painted apple moth (PAM; Teia anartoides Walker: Lepidoptera: Lymantriidae) incursion and to determine which plants were being attacked. Most PAM were found on the wattle species, in particular Paraserianthes lophanta and Acacia mearnsii. Other species with large numbers of PAM included the native Corynocarpus laevigatus (karaka) and Avicennia marina (grey mangrove). The large number of PAM on these New Zealand species would not have been predicted from the known unrelated Australian hosts. The relatively high number of PAM found on inanimate objects demonstrated the mobility of PAM larvae and that plants upon which few larvae were found may not be suitable hosts for PAM. [ABSTRACT FROM AUTHOR]

Ceratocystis albifundusis an important fungal pathogen ofAcacia mearnsiitrees in South Africa. In a previous study, a high level of gene diversity was demonstrated in a South African population ofC. albifundus. This, together with the occurrence of the pathogen on nativeProteaspecies and its exclusive occurrence in South Africa, led to the hypothesis thatC. albifundusis probably native to that country. More recently,C. albifundushas been reported fromA. mearnsiiin south-western Uganda. The aim of this study was to compare the populations ofC. albifundusfrom Uganda and South Africa based on genetic diversity, population structure and possible gene flow. This was achieved using codominant microsatellite markers developed for the closely related speciesCeratocystis fimbriata. Available isolates for comparison were from six different areas of South Africa and six jungle stands in Uganda. Eight of the 11 available markers amplified loci inC. albifundus. Gene diversity was higher in the Ugandan population, but genotypic diversity was greater for the South African isolates. There were no common genotypes between the two populations and they shared only 22% of the total alleles. The populations were genetically isolated from each other and highly substructured within. There was no association between isolates collected from the same geographic locations, and gene flow between the two populations was low. Results suggest thatC. albifunduswas probably not introduced into Uganda from South Africa but rather that an ancestral population, yet to be discovered, is the source of both populations. [ABSTRACT FROM AUTHOR]

A study of the regeneration of an afromontane forest was carried out in Mgahinga Gorilla National Park (MGNP), south-western Uganda. The area landscape has been subjected to agricultural encroachment for the last 50 years. The landscape was changed by terracing and removing the indigenous vegetation and replacing it with exotic tree species. Stratified random sampling was employed in sampling the vegetation. There was a significant difference in species richness and density in the three habitat types. The natural forest supported the highest stem density (75%) and the lowest stem density (4%) was recorded under exotic woodlots. Seedlings (<2 cm, diameter at breast height) accounted for the majority of juveniles in the three habitats. The natural forest had the highest density (24,625 seedlings ha−1) and exotic woodlots supported the lowest stem density (1350 seedlings ha−1). The level of regeneration in the encroachment area is influenced by the intensity of cultivation and soil nutrients. The advanced growth beneath the exotic woodlots, especially black wattle ( Acacia mearnsii) and Eucalyptus sp. stands is relatively impoverished. This condition beneath the exotic species suggests that a low diverse community of native species is able to exploit this environment. [ABSTRACT FROM AUTHOR]

A method of analysis of small volumes of gases from bulky plant organs, using mass spectrometry, is described. Results obtained from woody stems of Acacia mearnsii indicate that the most actively metabolizing tissues exist in an environment whose gaseous component is almost exclusively carbon dioxide. This observation is consistent with previous observations on the effect of carbon dioxide on the formation of compounds characteristic of heartwood in A. mearnsii. [ABSTRACT FROM AUTHOR]

A dieback of Acacia mearnsii trees was observed in the Mkomasi river valley. Natal Province, South Africa. A fungus, tentatively identified as Ceratocystis fimbriata, was consistently isolated from affected twigs and branches. Reinoculation of the pathogen resulted in the development of typical wilt and dieback of A. mearnsii seedlings and saplings and in a dieback of Protea cynaroides plants. This is the first report of this disease in South Africa. [ABSTRACT FROM AUTHOR]

The state of knowledge of the transition of sapwood into heartwood in trees is reviewed, and attention is drawn to the composition of the gas mixture available to such cells as remain alive in wood. The probable effect of such a mixture is postulated and experiments indicate that the high concentrations of carbon dioxide known to exist inside wood are conducive to formation of compounds known to be typical of the heartwood of Acacia mearnsii. [ABSTRACT FROM AUTHOR]

The article focuses on habitat fragmentation and the increasing mortality of the endangered Squirrel glider due to collision with vehicles. Measures to migrate the barrier effect on the crossing rate across the Goulburn valley highway of the squirrel glider are presented. The Goulburn valley freeway influences the foraging movement of Squirrel Gliders. The study also represents the gliding ability of the male squirrel glider, and the building of trialling rope bridges and strategically located poles to facilitate gliding.

Invasive alien trees increase native tree stress and may increase attack by herbivores and pathogenic fungi. Alien tree removal should ameliorate such impacts. Here we compared the levels of damage by phylopathogenic fungi and folivorous insects on Brabejum stellatifolium and Metrosideros angustifolia (native trees) and Acacia mearnsii (invasive tree species) among near-pristine, invaded and restored sites. Generally, foliar damage levels were higher at invaded than at near-pristine sites. Damage levels at restored sites were similar, or even higher than those at invaded sites. Decreased native tree species richness did not explain these patterns, as restored sites had native tree species richness levels similar to those of near-pristine sites. Increased host abundance and leaf nitrogen content did not significantly correlate with increased damage in most cases. Therefore, plant species richness recovers following restoration, but native trees still experience increased pressure from folivores and phylopathogenic fungi, which may even exceed levels experienced at invaded sites, thus impacting recovery trajectories. [ABSTRACT FROM AUTHOR]

An abstract of the article "First report of Phytophthora boehmeriae on black wattle in Brazil" is presented. Phytophthora nicotianae is the main disease of black wattle in the country and is characterized by lesions at the trunk base with gum exudation. Different symptoms were observed in other plantations and were characterized by dark lesions without gum exudation on trunks. Isolates were studied and it showed that it matched two isolates of Phytophthora boehmeriae. Other results are cited.