Processing Ecological Data in R with the mefa Package

mefa is an R package for multivariate data handling in ecology and biogeography. It provides object classes to represent the data coded by samples, taxa and segments (i.e., subpopulations, repeated measures). It supports easy processing of the data along with relational data tables for samples and taxa. An object of class mefa is a project specific compendium of the dataset and can be easily used in further analyses. Methods are provided for extraction, aggregation, conversion, plotting, summary and reporting of mefa objects. Reports can be generated in plain text or LaTex. This paper presents worked examples on a variety of ecological analyses.

Data on the recent mollusc fauna of the western part of the Villány Hills, S Hungary

The western part of the Villány Hills hasn’t been investigated in a quantitative malacological way since before. This paper presents data on the recent mollusc fauna of the area based on 20 soil samples with equal volumes from 5 different sampling sites. Comparison of the newly and previously surveyed areas of the hills is also presented

Data on the recent mollusc fauna of the Fekete Hill (Villány Hills, S Hungary)

Mollusc assemblages of the Fekete Hill (5 sampling areas) were analysed on the basis of 20 soil samples taken in the years 1997–1999. The author presents data on the mollusc fauna of the Fekete Hill with new localities of some species

A test on the effectiveness and selectivity of three sampling methods frequently used in orthopterological field studies

To obtain unbiased data in entomological samplings the selectivity and effectiveness of methods should be known. Sweepnetting, direct search and dish trap, which are frequently used in orthopterology, were tested to get data on selectivity and effectiveness. Based on the number of collected individuals, sweepnetting was the most labour efficient, while the highest number of species was collected by direct search. Dish traps were most selective to ground-dwelling species. Sweepnetting and direct search were sensitive to grass-dwelling species. Our results underlines that none of the methods is universal, and a combination of sweepnetting and direct search provides the greatest benefits

Terepi adatlap a hazai epigeikus makrogerinctelenek elterjedésének és élõhelyi preferenciájának vizsgálatára

A jelen dolgozatban egy új terepi adatlapot ismertetünk, amely elsősorban a felszínen aktív gerinctelen állatok vizsgálatára alkalmas. Segítségével adatok gyűjthetők a terepi mintavétel körülményeiről és a vizsgált élıhely háttértényezőiről. Az így nyert adatok számítógépes adatbázisba kerülve sokoldalúan elemezhetők. Az elemzések eredményeképpen képet alkothatunk egyes fajok élőhelyi preferenciájáról és a fajgazdagságot, fajösszetételt meghatározó tényezőkről, a fajok különböző skálájú földrajzi elterjedéséről

A possible connection between macroclimate and shell morphometry of Granaria frumentum (Draparnaud, 1801) (Gastropoda: Chondrinidae)

We measured 726 specimens of Granaria frumentum (Draparnaud, 1801) from Szársomlyó and Oltárkő, and this was completed with earlier data from Kereszteskő. We aimed to show the relationship between macroclimatic factors and shell morphometry of Granaria frumentum.We found differences among the populations came from the three different localities according to the macroclimatic trend. Correlation between mode of height of the shells in the populations and mean temperature is positive, correlation between mode of height of the shells in the populations and the ammount of precipitation is negative

Multiple-Table Data in R with the multitable Package

Data frames are integral to R. They provide a standard format for passing data to model-fitting and plotting functions, and this standard makes it easier for experienced users to learn new functions that accept data as a single data frame. Still, many data sets do not easily fit into a single data frame; data sets in ecology with a so-called fourth- corner problem provide important examples. Manipulating such inherently multiple-table data using several data frames can result in long and difficult-to-read workflows. We introduce the R multitable package to provide new data storage objects called data.list objects, which extend the data.frame concept to explicitly multiple-table settings. Like data frames, data lists are lists of variables stored as vectors; what is new is that these vectors have dimension attributes that make accessing and manipulating them easier. As data.list objects can be coerced to data.frame objects, they can be used with all R functions that accept an object that is coercible to a data.frame

Data on the terrestrial Isopoda fauna of the Alsó-hegy, Aggtelek National Park, Hungary

Field surveys in dolines of Alsó-hegy, Aggtelek Karst (Hungary) yielded 10 terrestrial isopod species. Despite of the relatively low species richness, we would like to emphasize the high naturalness of the area indicated by the presence of endemic and rare species