284 research outputs found
Organic amendment increases arbuscular mycorrhizal fungal diversity in primary coastal dunes
Plastic pots were inserted beneath seedlings of a shallow-rooted C4 grass species, Ischaemum indicum, with and without a root-impenetrable nylon sachet filled with organic matter (OM) amendment, at seven stations along an interrupted belt transect in which plant community and soil chemistry had been previously surveyed. The transect was perpendicular to mean high-water mark (MH-WM) across a primary coastal dune system in Goa, India, where summer monsoon is the predominant weather feature. The Quadrat survey of plant frequency was made in stations when the above-ground biomass was estimated to be highest. Arbuscular mycorrhiza fungal (AMF) spore density and diversity were determined morphologically in amended and control pots soils, and in OM sachet residues, after host-plant desiccation when monsoon rains had ceased. Twenty-seven AM fungal spore morphotypes were isolated from the pots containing OM amended rhizosphere soils, 19 from controls and 14 from OM residues in the sachets. Gigaspora margarita proved to be the dominant spore in all treatments. Eight morphotypes recovered from amended pots were not recovered from the controls. There was an increasing trend in species diversity in amended pots away from MH-WM. Spore recovery from the three regimes showed variable distribution that indicated differing AMF species strategies
Internal and external match loads of university-level soccer players: a comparison between methods
The aim of this study was to use individualized intensity zones to compare the external (velocity and player load, PL) and internal loads (heart rate, HR) of a cohort of university-level soccer players. Thirteen soccer players completed a 40-m maximum speed test and the Yo-Yo intermittent recovery test 1 (Yo-Yo IR1) to determine individualized velocity and HR thresholds. Heart rate values and global positioning system (GPS) data of each player were recorded during 5 league matches. A large (r = 0.46; p </= 0.01) correlation was found between time spent in the low-intensity (LI) velocity zone (LIVZ) and the LI HR zone. Similarly, there were moderate (r = 0.25; p </= 0.01) to large (r = 0.57; p </= 0.01) correlations between the relative and absolute time spent in the moderate-intensity (MI) velocity zone (MIVZ) and the MI HR zone. No significant correlations (p </= 0.01) existed between the high-intensity (HI) velocity zones (HIVZ) and the HI HR zone. On the other hand, PL showed significant correlations with all velocity and HR (absolute and relative) variables, with the exception of a nonsignificant correlation between the HI HR variables and PL. To conclude, PL showed good correlations with both velocity and HR zones and therefore may have the potential to serve as a good indicator of both external and internal soccer match loads
The role of climate change and food supply on winter populations of seed-eating birds
We studied the populations of four seed-eating bird species throughout the winter during a 30-year study in the forests of the Tatarstan Republic, Russia. Numbers of all species fluctuated from year-to-year by several orders of magnitude but with a significant underlying trend for increased numbers associated with rising temperatures and a greater food supply. We question whether the traditional view that such birds move further south only after exhausting the food supply is too simplistic. We believe that the severity of winter, or lack of it, is highly influential on the mortality and movements of these characteristic birds of the boreal forest zone
Primary sand-dune plant community and soil properties during the west-coast India monsoon
A seven-station interrupted belt transect was established that followed a previously observed plant zonation pattern across an aggrading primary coastal dune system in the dry tropical region of west-coast India. The dominant weather pattern is monsoon from June to November, followed by hot and dry winter months when rainfall is scarce. Physical and chemical soil characteristics in each of the stations were analysed on five separate occasions, the first before the onset of monsoon, three during and the last post-monsoon. The plant community pattern was confirmed by quadrat survey. A pH gradient decreased with distance from the shoreline. Nutrient concentrations were deficient, increasing only in small amounts until the furthest station inland. At that location, there was a distinct and abrupt pedological transition zone from psammite to humic soils. There was a significant increase over previous stations in mean organic matter, ammonium nitrate and soil-water retention, although the increase in real terms was small. ANOVA showed significant variation in electrical conductivity, phosphorus, calcium, magnesium and sodium concentrations over time. There was no relationship between soil chemistry characteristics and plant community structure over the transect. Ipomoea pes-caprae and Spinifex littoreus were restricted to the foredunes, the leguminous forb Alysicarpus vaginalis and Perotis indica to the two stations furthest from the strand. Ischaemum indicum, a C4 perennial grass species adopting an ephemeral strategy was, in contrast, ubiquitous to all stations
The contrasting invertebrate fauna of freshwater habitats in the Swavesey fens of East Anglia
During July and August 1988, 21 ponds and 33 ditch sites were sampled at Swavesey fens in East Anglia. Water from each site was collected and analysed at monthly intervals in the year preceding faunal sampling. Temperature and oxygen were measured on site. The "quality" of the faunal community was assessed by three approaches: a modification of the BMWP scoring system (Biological Monitoring Working Party); faunal richness was calculated as the number of faunal "groups" at each site; and by using Simpson's index of diversity. Statistical analysis was carried out to explore the relationships between sites, environmental variables and faunal diversity. The survey clearly showed the detrimental effects of elevated nitrate and phosphate from agricultural sources and the localised impacts of treated sewage effluent on invertebrates in ditches
Synchrony in the phenology of a culturally iconic spring flower
We examine the flowering phenology of the cultural iconic Spring Snowflake Leucojum vernum, a considerable tourist attraction, recorded from two sites in western Poland. Flowering dates at the two sites were closely correlated but about 6 days later at the more natural area. The end of flowering was associated with the start of canopy leafing. Early flowering was related to a longer flowering season which may benefit ecotourism under future climate warming
Birds crossing over roads: species, flight heights and infrastructure use
How high do birds fly above roads, and how do they use the road infrastructure (bridges, lampposts etc.)? These questions are rarely explored in ecological studies but were addressed by us during research in 2016–2018 in southern Poland. In total, 1665 individual birds belonging to 24 species were recorded. Species differed significantly in the height at which they crossed over roads, but about 30% of all crossings were at heights below 12 m, hence at potential collision heights. The proportion of birds perching on lampposts in the central reservation between carriageways also differed significantly between species. The surrounding landscape and road infrastructure, especially lampposts, modified the species composition associated with roads. This knowledge has practical importance, not only in regard to collisions, but also to much less studied aspects such as plant seed dispersal and/or corrosion of the infrastructure. Lampposts, as a taller component of the infrastructure, may not directly affect vehicle-bird collisions, but a flight to them may be a risky business, and we recommended higher lampposts to discourage low-level flights. This information may need to be incorporated into future studies on road ecology, as well as in mitigation programs
Out of sight, out of mind: ethnic inequalities in child protection and out-of-home care intervention rates
This paper examines the interlocking roles of ethnicity and deprivation in producing inequities in the proportion of children who are subject to state child protection interventions. In contrast to the USA, ethnic inequities have had little attention in research or policy in the UK and across Europe, and administrative data are limited and methodologically weak. A study of over 10 per cent of all children on child protection plans or who were looked after in out-of-home care in England in March 2012 is reported. Children from ethnic minority categories were much more likely than 'White' children to be living in disadvantaged areas and this has to be taken into account when examining intervention rates. Controlling for deprivation and examining small subgroups of the broad ethnic categories radically alters the simple understanding that 'Black' children are overrepresented compared to White amongst children in out-of-home care, while 'Asian' children are underrepresented. While this study could not explain these patterns, it reinforces the importance of both socio-economic circumstances and ethnicity for understanding inequities in intervention rates. The evidence underlines the powerful moral and economic case for action to reduce inequities in powerful state interventions in family life, not only in England, but internationally
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