The Effects of Habitat Structure and Floristics on the Densities of Bird Species in Wandoo Woodland.

1988 ◽  
Vol 15 (5) ◽  
pp. 499 ◽  
Author(s):  
GW Arnold

Censuses were taken in the springs of 3 consecutive years of the birds in twelve 2-ha sites in remnants of wandoo woodland in SW Western Australia. The sites were distributed between 3 vegetation types: (a) Eucalyptus wandoo open forest; (b) E. accedens open forest with Dryandra sessilis; and (c) Casuarina/Acacia low open forest. The 3 vegetation types had similar numbers of birds but different species diversities. Although the relative numbers in each group of species changed from year to year, the relative numbers were the same each year in the different vegetation types. The avian communities of (a) and (c) had a higher diversity than in (b). In (c) there were significantly fewer nectar and bark feeders than in (a) or (b), but more ground insectivores. In (a) there were significantly more parrots and leaf gleaners than in the other vegetation types, whereas (b) had very high numbers of nectar feeders but low numbers of ground/low shrub insectivores. Statistically significant relationships were established between the abundance of 13 of the most common bird species and habitat variables. These regressions showed that both floristics and structure strongly affected the abundance of a species. Between 42 and 95% of the variance in numbers was accounted for.

OENO One ◽  
2004 ◽  
Vol 38 (2) ◽  
pp. 131
Author(s):  
Samir Chebil ◽  
Jean Roudet ◽  
Abdelwahed Ghorbel ◽  
Bernadette Dubos

<p style="text-align: justify;">Grey rot, caused by <em>Botrytis cinerea</em>, is nowadays the most damaging disease of the Tunisian vineyard. The fungus attacks berries at the maturation stage and causes important economic losses. The protection of vineyard against this disease is very difficult due to the fungus characteristics. In fact <em>B. cinerea</em> is in the border of parasitism and saprophytism, in pre-veraison it usually survive as saprophyte then it attacks berries before their maturation. The purpose of this study is to highlight the role of pre-veraison’s contamination by <em>B. cinerea</em> on the development of the Grey rot on the berries after veraison.</p><p style="text-align: justify;">The results revealed that at the pre-veraison stage, <em>B. cinerea</em> grows as a saprophyte. The fungus’s rate presence is low on the barks (less than 10 %), very high on the floral buds (between 5 and 27 %) and relatively high in the immature berries (about 20 %). The quantification of bunches pollution, showed that the rate of contaminations by <em>B. cinerea</em> is very high (more than 70 %).</p><p style="text-align: justify;">On the other hand, the mapping out showed up that outbreak of the disease happened after veraison on Muscat d’Italie. Also, the rate of berries’ rot, were different each year, in relation to the climatic conditions and plant’s physiology. We found that the rate of rot inside bunches is relatively high (between 15 and 40 %) due to condia on stem or <em>B. cinerea</em> latent. The statistical analysis showed significant relationships between the rate of latent <em>B. cinerea</em> and the appearance of the disease after the veraison stage. Also, the scoring of conidia observed in the air showed a big activity of the fungus during flowering and the maturation of berries.</p>


2003 ◽  
Vol 30 (4) ◽  
pp. 321 ◽  
Author(s):  
Ian Abbott ◽  
Amanda Mellican ◽  
Michael D. Craig ◽  
Matthew Williams ◽  
Graeme Liddelow ◽  
...  

In 1985 new silvicultural prescriptions for managing jarrah (Eucalyptus marginata) forest in south-west Western Australia came into operation. The most extreme logging treatment (gap release) involved removal of most of the overstorey from patches no larger than 10 ha, followed by a regeneration fire. In the other logging treatment (shelterwood), less wood was removed from a larger area, also followed by a fire. This study examined the impact of these disturbances on the avifauna by monitoring species richness and abundance of birds one year before logging, one year before burning, and for five years after burning. Although 68 bird species were recorded during the seven years of the study, 29 of these were detected fewer than 15 times. Of the other 39 bird species recorded, only two (Gerygone fusca and Acanthiza apicalis) showed a statistically significant treatment effect over time on their abundance. The abundance of G. fusca initially declined in the disturbed treatments and by Year 7 of the study (5 years post-fire) in the gap-release treatment had not recovered its original abundance. A. apicalis increased its abundance in both shelterwood and gap-release treatments. By Year 7, both species in the logged treatments had abundances similar to those in the unlogged treatments. Total abundance of all species varied little across treatments. Species richness was highest by Year 7 in the shelterwood and lowest in the gap-release treatment. In some years community structure varied more at the external-reference sites (not recently logged or burnt) than at the gap-release sites. In particular, there was little overlap in community structure in the external-reference treatment between the first and final years, whereas the pre-logging and final year in the gap-release treatment showed a high degree of overlap. These differences are suggestive of overriding short-term annual variation in broad-scale factors rather than local factors. Yearly variation in rainfall and temperature was documented; during low rainfall periods, populations of foliage arthropods may have been reduced.


2013 ◽  
Vol 61 (3) ◽  
pp. 187 ◽  
Author(s):  
T. L. Moore ◽  
L. E. Valentine ◽  
M. D. Craig ◽  
G. E. StJ. Hardy ◽  
P. A. Fleming

Globally, many forests and woodlands are in decline. The marked loss of canopy foliage typical of these declines results in reduced foraging resources (e.g. nectar, pollen, and insects) and, subsequently, can reduce habitat quality for woodland birds. In south-west Western Australia, patches of Eucalyptus wandoo woodlands have shown a decline in condition since at least 2002. We investigated how changes in E. wandoo condition affect the woodland bird community. Foraging activities of three bird species were recorded for 20 sites in Dryandra State Forest and Wandoo Conservation Park either by conducting watches on focal trees (‘sitting’ method), or following individuals through the woodland (‘following’ method). Condition assessments of trees used by the birds were compared with those for trees available at the study site. Weebills (Smicrornis brevirostris; canopy insectivore) displayed preference for healthy trees (low amounts of canopy dieback), whereas rufous treecreepers (Climacteris rufa; bark-foraging insectivore) preferred trees with a higher proportion of dead branches. Yellow-plumed honeyeaters (Lichenostomus ornatus; insectivore/nectarivore) foraged in older, larger E. wandoo trees having full canopies with few signs of tree decline. Tree declines, such as that happening in E. wandoo, alter the foraging resources and habitat available to woodland birds.


1979 ◽  
Author(s):  
J. G. Kelton ◽  
P. B. Neame ◽  
I. Walker ◽  
A. G. Turpie ◽  
J. McBride ◽  
...  

Thrombotic thrombocytopenic purpura (TTP) is a rare but serious illness of unknown etiology. Treatment by plasmapheresis has been reported to be effective but the mechanism for benefit is unknown. We have investigated the effect of plasmapheresis in 2 patients with TTP by quantitating platelet associated IgG (PAIgG) levels prior to and following plasmapheresis. Both patients had very high levels of PAIgG at presentation (90 and A8 fg IgG/platelet respectively, normal 0-5). in both, the PAIgG levels progressively fell to within the normal range and the platelet count rose following plasmapheresis. One patient remained in remission with normal platelet counts and PAIgG levels. The other relapsed after plasmapheresis and the PAIgG level rose prior to the fall in platelet count. Plasmapheresis was repeated and resulted in normalization of both the platelet count and PAIgG level. It is suggested that plasmapheresis removes antiplatelet antibody or immune complexes which may be of etiological importance in this illness.


1994 ◽  
Vol 29 (7) ◽  
pp. 327-333
Author(s):  
Y. Matsui ◽  
F. Yamaguchi ◽  
Y. Suwa ◽  
Y. Urushigawa

Activated sludges were acclimated to p-nitrophenol (PNP) in two operational modes, a batch and a continuous. The operational mode of the PNP acclimation of activated sludges strongly affected the physiological characteristics of predominant microorganisms responsible for PNP degradation. Predominant PNP degraders in the sludge in batch mode (Sludge B) had lower PNP affinity and were relatively insensitive to PNP concentration. Those of the sludge in continuous mode (Sludge C), on the other hand, had very high PNP affinity and were sensitive to PNP. MPN enumeration of PNP degraders in sludge B and C using media with different PNP concentrations (0.05, 0.2,0.5 and 2.0 mM) supported the above results. Medium with 0.2 mM of PNP did not recover PNP degraders in sludge C well, while it recovered PNP degraders in sludge B as well as the medium with 0.05 mM did. When switching from one operational mode to the other, the predominant population in sludge B shifted to the sensitive group, but that of sludge C did not shift at the given loading of PNP, showing relative resistance to inhibitive concentration.


2019 ◽  
Vol 11 (3) ◽  
pp. 328-341
Author(s):  
Rifki Ismal ◽  
Nurul Izzati Septiana

Purpose The demand for Saudi Arabian real (SAR) is very high in the pilgrimage (hajj) season while the authority, unfortunately, does not hedge the hajj funds. As such, the hajj funds are potentially exposed to exchange rate risk, which can impact the value of hajj funds and generate extra cost to the pilgrims. The purpose of this paper is to conduct simulations of Islamic hedging for pilgrimage funds to: mitigate and minimize exchange rate risk, identify and recommend the ideal time, amount and tenors of Islamic hedging for hajj funds, estimate cost saving by pursuing Islamic hedging and propose technical and general recommendations for the authority. Design/methodology/approach Forward transaction mechanism is adopted to compute Islamic forward between SAR and Rupiah (Indonesian currency) or IDR. Findings – based on simulations, the paper finds that: the longer the Islamic hedging tenors, the better is the result of Islamic hedging, the decreasing of IDR/USD is the right time to hedge the hajj funds and, on the other hand, the IDR/SAR appreciation is not the right time to hedge the hajj funds. Findings Based on simulations, the paper finds that: the longer the Islamic hedging tenors, the better is the result of Islamic hedging, the decreasing of IDR/USD is the right time to hedge the hajj funds and, on the other hand, the IDR/SAR appreciation is not the right time to hedge the hajj funds. Research limitations/implications The research suggests the authority to (and not to) hedge the hajj fund, depending on economic conditions and market indicators. Even though the assessment is for the Indonesian case, other countries maintaining hajj funds might also learn from this paper. Originality/value To the best of author’s knowledge, this is the first paper in Indonesia that attempts to simulate the optimal hedging of hajj funds.


2005 ◽  
Vol 495-497 ◽  
pp. 603-608 ◽  
Author(s):  
Atsushi Todayama ◽  
Hirosuke Inagaki

On the basis of Taylor-Bishop-Hill’s theory, many previous theoretical investigations have predicted that, at high rolling reductions, most of orientations should rotate along theβfiber from {110}<112> to {123}<634> and finally into the {112}<111> stable end orientations. Although some exceptions exist, experimental observations have shown, on the other hand, that the maximum on the β fiber is located still at about {123}<634> even after 97 % cold rolling. In the present paper, high purity Al containing 50 ppm Cu was cold rolled up to 99.4 % reduction in thickness and examined whether {112}<111> stable end orientation could be achieved experimentally. It was found that, with increasing rolling reduction above 98 %, {110}<112> decreased, while orientations in the range between {123}<634> and {112}<111> increased, suggesting that crystal rotation along the βfiber from {110}<112> toward {123}<634> and {112}<111> in fact took place. At higher rolling reductions, however, further rotation of this peak toward {112}<111> was extremely sluggish, and even at the highest rolling reduction, it could not arrive at {112}<111>. Such discrepancies between theoretical predictions and experimental observations should be ascribed to the development of dislocation substructures, which were formed by concurrent work hardening and dynamic recovery. Since such development of dislocation substructures are not taken into account in Taylor-Bishop-Hill’s theory, it seems that they can not correctly predict the development of rolling textures at very high rolling reductions, i. e. stable end orientations. On annealing specimens rolled above 98 % reduction in thickness, cube textures were very weak, suggesting that cube bands were almost completely rotated into other orientations during cold rolling. {325}<496>, which lay at an intermediate position between {123}<634> and {112}<111> along theβfiber, developed strongly in the recrystallization textures.


1985 ◽  
Vol 12 (3) ◽  
pp. 461 ◽  
Author(s):  
I Abbott ◽  
PV Heurck

A study of foraging by 10 bird species suggests that selective logging of large Eucalyptus marginata will only have affected Melithreptus lunatus, but that proposed silvicultural treatments, including removal of Banksia grandis, may affect several other bird species.


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