Comparison of spring and summer clutches of Great Crested Grebes (Podiceps cristatus)

The intensively farmed fishponds of the Třeboň Basin in South Bohemia, Czech Republic host a substantial number Great Crested Grebe (Podiceps cristatus) pairs that nest later than the expected spring season and instead in summer, which may be associated with fishpond farming. A two-factor nested ANOVA of Great Crested Grebe egg and clutch characteristics showed no differences between spring (May-June) and summer (July - August) seasonal clutches. High egg total volume in spring nests was significantly related to both decreasing distance between nests and decreasing number of nests on the fishpond. The increase of total egg volume in summer nests was significantly related to the distance to the edge of littoral vegetation. There is no substantial difference between spring and summer egg characteristics, but total egg volume in spring nests is dependent on other characteristics that those in summer nests.

Model diagnostics for detecting and identifying method repeatability outliers in precision studies: application to a homogeneity study under a two-stage nested ANOVA

In this paper we illustrate the use of statistical model diagnostics as an approach to identifying method repeatability outliers in precision experiments. We describe how this approach addresses the well-known shortcomings of Cochran’s test which is prescribed for this purpose in ISO 5725-2:1994.

Parameter Analysis of Electromagnetic Braking Using Fully Nested and Two Way ANOVA

This paper presents the statistical analysis that was used to define optimized parameter for the electromagnetic braking using eddy current study. It illustrates parametric study on four different parameters affecting the braking performance using eddy current which are air-gap, number of electromagnet turns, current induced and disc thickness. These four parameters are defined as the factors which contribute to the reduction of RPM speed as the effect. Fully nested ANOVA was used as the first analysis to determine two most significant factors to eddy current braking system. Then, two-way ANOVA was applied to clarify the most significant factors to be used as the controllable parameters in the verification study. Results from both ANOVA test shows that current induced and air-gap are the two most significant factors that affected braking using eddy current.

Measuring relative flower size in Anthurium (Araceae) as a continuous quantitative character

Relative flower size (RFS) was studied quantitatively in natural populations of Anthurium erskinei (one population) and A. talmonii (two populations) to investigate its potential as a taxonomic descriptor. RFS is defined as the ratio of spadix diameter and transverse floral width in the same region of the spadix. Variation was examined within and between inflorescences, populations and species. Within a single spadix, RFS may vary significantly between basal and upper spadix zones but usually not between basal and middle zones. Within populations, RFS does not differ significantly between spadix zones. Log-transformed RFS values showed significant inter-population differences. In nested ANOVA, between-species variance accounted for >90% of total variance. In A. talmonii between-population within-species variance amounted to >78% of total variance (mean RFS values), and within-spadix-zone within-spadix variance accounted for >31% of total variance (individual values). Bootstrap sampling showed that five pairs of flower and spadix diameter measurements per spadix would provide an adequate estimate of mean RFS for each population. The study suggests that RFS can be a useful quantitative taxonomic floral character for comparing species and populations in the genus Anthurium.

KESUBURAN PERAIRAN DITINJAU DARI KANDUNGAN KLOROFIL-A FITOPLANKTON : STUDI KASUS DI SUNGAI WEDUNG, DEMAK

Perairan Sungai Wedung merupakan ekosistem pesisir yang banyak dimanfaatkan untuk berbagai kegiatan manusia. Hal tersebut tentunya berpengaruh terhadap kesuburan perairan Sungai Wedung. Kesuburan di perairan tersebut dipengaruhi oleh plankton, faktor kimia, fisika dan juga kandungan Klorofil-A. Pengukuran kandungan klorofil-a fitoplankton merupakan salah satu alat pengukuran kesuburan suatu perairan. Klorofil-a fitoplankton adalah suatu pigmen aktif dalam sel tumbuhan yang mempunyai peran penting dalam berlangsungnya proses fotosintesis perairan. Penelitian dilakukan pada bulan April – Mei 2013 di Sungai Wedung, Demak bertujuan untuk mengetahui aktivitas manusia terhadap sebaran klorofil-a, keterkaitan antara klorofil-a dan kelimpahan fitoplankton dan tingkat kesuburan perairan berdasarkan kandungan klorofil-a fitoplankton. Metode yang digunakan adalah metode studi kasus dengan teknik pengambilan sampel menggunakan metode “Sample Survey Method”. Hasil penelitian menunjukkan bahwa hasil analisis data klorofil menggunakan metode anova tersarang (nested anova) diperoleh nilai P untuk stasiun cukup besar sehingga tidak memberikan perbedaan yang nyata pada taraf kepercayaan 95 %. Akan tetapi perbedaan akan nyata pada taraf 90%. Hubungan antara klorofil-a dengan kelimpahan fitoplankton secara linear menunjukkan nilai keeratan yang tinggi dengan nilai koefisien korelasi sebesar 0,93 dan koefisien determinasi sebesar 0,8633 dimana 86% klorofil-a dipengaruhi oleh kelimpahan fitoplankton. Berdasarkan nilai rata-rata klorofil-a yang diperoleh sebesar 1,039863 mg/l dapat disimpulkan bahwa perairan Sungai Wedung tergolong kedalam perairan yang bersifat oligotrofik.

Function of coprophagous beetles (Coleoptera: Scarabaeidae, Geotrupidae, Hydrophilidae) in cattle pastures inferred from pitfall trapping data

Function of coprophagous beetles (Coleoptera: Scarabaeidae, Geotrupidae, Hydrophilidae) in cattle pastures inferred from pitfall trapping dataAn analysis of data on the dry weight biomass of coprophagous beetles in standardized dung (4.5 l) was conducted in order to characterize the spatial and the seasonal distribution of the beetles' biomass in cattle pastures and to elucidate their function in dung decomposition. Nested Anova with factors of farm, site (nested in farm), seasonal period and year was used to evaluate the effect of these factors on the biomass of four functional species groups: the dung dwellers ofScarabaeidae(subfamilyAphodiinae), the dung dwellers ofHydrophilidae, the small tunnellers ofScarabaeidae(subfamilyCoprinae) and the large tunnellers ofGeotrupidae. The spatial variation of biomass (between the sites and the farms) was insignificant (P>0.05) in the two dung-dweller groups and in the large-tunnellers group. On the other hand, a significant (P<0.05) seasonal variation of biomass was found in all but the large tunneller group. In dung dwellers, the spring biomass was formed mainly by two species,Aphodius prodromusandA. sphacelatus. In summer, most of the biomass was accounted for bySphaeridium lunatum, S. scarabaeoidesandA. rufipes. In the two tunneller groups,Onthophagus fracticornis, Geotrupes stercorariusandG. spinigerformed a majority of the biomass in dung.