search for: sediment

Hello all, I'm new in R, and I have a data-frame like this (dput information below): Specie Fooditem Occurrence Volume 1 Schizodon vegetal 1 0.05 2 Schizodon sediment 1 0.60 3 Schizodon vegetal 1 0.15 4 Schizodon alga 1 0.05 5 Schizodon sediment 1 0.90 6 Schizodon sediment 1 0.30 7 Schizodon sediment 1 0.90 8 Astyanax terrestrial_insect...

Dear Colleagues, I am attempting to develop an optimization routine for a river suspended sediment mixing model. I have Calcium and Magnesium concentrations (%) for sediments from 4 potential source areas (Topsoil, Channel Banks, Roads, Drains) and I want to work out, based on the suspended sediment calcium and magnesium concentrations, what are the optimal contributions from each source area to...

...t;, "Schizodon intermedius", "Schizodon intermedius"), Weight = c(0.06, 0.01, 0.01, 0.33, 0.01, 3.5, 0.01, 0.04, 0.01, 0.01, 0.38, 0.29, 0.04, 0.03, 0.11, 0.04, 0.04, 0.03, 0.01, 0.01), Food.item = c("Fish", "Vegetal", "Alga", "MNI", "Sediment", "Fish", "Alga", "MNI", "Alga", "MNI", "Vegetal", "Vegetal", "Vegetal", "Alga", "Vegetal", "Alga", "MNI", "Sediment", "Sediment", "Vegetal")),...

Hi, I?m trying to make a barplot with the following dataframe, with information on relative frequency per sediment type (ST) for some species: Species ST1 ST2 ST3 SP_A 10 60 30 ... At x-axis are (should be ...) the species names and at y-axis the frequency per sediment, in stacked bars. I tried to use barplot command but with no results. Could anyone help me on this? Thanks in advance, Samanth...

Dear List, I am thinking about ways in which I might analyse some stratigraphic data. The nature of the data series I have generates a number of issues: 1) The data I have in mind come from a sediment core sequence taken from the bottom of a lake. The sequence is sliced into a priori defined slices, in this case 0.2cm per slice. in this way a sequence of 0.2cm slices is produced for the entire core. 2) Each slice is assigned a date (plus some error) using radiometric dating techniques and a...

Dear all, I would like to create a vertically stacked area chart in R. The data are presented in the attached text file. I would like to see the trend in values for the different groups with sediment depth (that's why I would like to create a vertically stacked chart; normally sed_depth should be = x, but I want it plotted on the y-axis). In the packages available to create stacked area plots, there seems to be an option for horizontally stacked area plots only. Does anybody know how I shou...

Dear everyone, I would like to create a kite chart in which I plot densities (width of the vertical kites) in relation to sediment depth (on reversed y-axis) for 6 different locations (Distances from seep site, on x-axis on top of the plot). The dataset I would like to use is: Distance_from_seep_site Sedimentdepth Density 1100 0 107.8 1100 1 264.6 1100 2 284.2 1100 3 470.4 1...

I currently work on a draft of an aquatic bioassessment. The conditions tested are the following: ER river water T dechlorinated water control 0.5 + 0.5mg / L of malate T + 1 dechlorinated water control + 1g / L of malate T ED dechlorinated water control SED + ER + river water sediment SED ED + sediment + water dechlorinated. It is the result of AChE in muscle (fillet of fish). The production of acetylcholine is followed with a spectrophotometer every 15 seconds for two minutes. The results are presented in the following table: traitement t15 t30 t45 t60 t75 t90 t105 t120 ER 0....

Hello there, Is there a functionality or command that generates axes in the shape of a capital Greek letter gamma (upside down L) ? I use these for making sediment profiles. I have read through help-lists, tried different things and asked several people but never got a satisfactory result. I've tried the following: xx <- c(2,4,6,5.8,5,4,3,1.5,0, 0, 0, 0) yy <- (0:-11) plot(NULL, NULL, ylab="depth (cm)", xlim=c(0,8), ylim=c(-12,1), las=1,...

Dear R helpers, I would like to model temporal trend of biological remains in sediment cores. All samples are temporally auto-correlated and I would like to take this effect into account. Initially I thought that I could use AR(1) or ARIMA functions but these functions only work with regular temporal intervals between samples. Hence I would like to use a continuous time AR(1) that...

...high which are based upon percent seagrass regrowth into the injury over time. I wish to be able to predict the level of recovery of future vessel grounding sites based upon a number of categorical / continuous predictor variables used here including (but not limited to) such parameters as: sediment grain size, wave exposure, original size (volume) of the injury, injury age, injury location. When I run /rpart/, the data is split into only two terminal nodes based solely upon values of the original volume of each injury. No other predictor variables are considered, even though I have inclu...

Working - among other things- in the field of (short & long term) electricity forecast, we are now using too many & too expensive pieces of licensed software: SAS, SPSS, EViews. This "sedimentation" is due to the fact that my predecessors in the past used different consultant companies to manage each procedure. Having attended the useR2004! Conference with the aim of assessing if R ALONE could "glue" all those fragmented and isolated procedures, I'm almost convinced n...

Hi all, I hope that i've posted this in the correct place. if not, please accept my apologies (where should this go?) I have carried out experimental removal of bivalves at 2 intertidal shores. Bivalves were removed by raking of surface sediments. I wish compare the biomass values of for a total of 8 species between the 2 shores My 3 treatments are: Undisturbed Controls (Cont), Procedural Controls (Proc) and Experimetnally Fished (Fished). As Fished and Proc have both experienced disturbance, I set the model using 2 factors as follows:...

Fellow R users, I'm using the BCE {BCE} function to run a Bayesian sediment mixing model. The aim is to find the optimum % contribution from each of the 4 source areas that can yield the target geochemistry. I have geochemistry for 4 source areas called Rat: Rat<-read.table(text="CaO MgO Na2O Al2O3 Topsoils 2.511250 0.7445500 0.7085500 14.10375...

...13694 Global Ocean Sampling Expedition Metagenome 2 20823 13696 5-Way (CG) Acid Mine Drainage Biofilm Metagenome 3 - 13699 Waseca County Farm Soil Metagenome 4 - 13702 Methane-Oxidizing Archaea from Deep- Sea Sediments 5 - 13729 Pacific Beach Sand Metagenome Thanks for your help. Hopefully this is something simple that I missed in the documentation/help. Chris -- ------------------- Chris Stubben Los Alamos National Lab BioScience Division MS M888 Los Alamos...

...the image (line 2), # converts the image to grayscale data (line 3), and calculates the autocorrelation curve # for offset distances of one pixel to 99 pixels (lines 7–10). This code can be used to # perform steps (4) and (6) listed above in the Summary of Steps to Calculate Grain # Size of Natural Sediment. ColorData = imread(‘ImageName.jpg’); x <- read.jpeg("sed2.jpg")# opens the image imshow(ColorData); plot(x) # plot image data = double(rgb2gray(ColorData)); x=rgb2grey(x) # transform in grayscale, the image ; # example of a similar data matrix: data = double(0.54878431372549,0.468,0....

I am trying to use the glm.nb proceedure in the new MASS library. I have count data (of snails) taken from a number of habitats (artesian springs). I want to model the abundances, including an effect of the organic content of the sediment. When I try to fit a model like: nb.model.p <- glm.nb(abundance~Organics.per.wt) I get the error message: Error: no valid set of coefficients has been found:please supply starting values I looked in the help for the glm proceedure and found the "start()" statement for specifying c...

Hello, I would like to know if there is a function in an R library that allows to do cluster analysis under contiguity constraints ? Thank you very much for your answer ! Lise Bellanger -- Lise Bellanger, Universit? de Nantes D?partement de Math?matiques, Laboratoire Jean Leray UMR CNRS 6629 2, Rue de la Houssini?re BP 92208 - F-44322 Nantes Cedex 03 T?l. : (33|0) 2 51 12

Dear All, I am a researcher doing research in plant growth and I have a statistical problem that seems to not be able to handle. Recently, I conducted an experiment about plant growing in three different nutrient-level sediments. I harvested these every three week (three harvests in all). Some growth traits of these plants were recorded (e.g. total biomass, leaf biomass and stem biomass). In addition, I found that the total plant biomass may also influence these traits. So, I am going to use total biomass as covariate...

Dear All, I am using a specific approach for my master thesis. In essence, a supervised reclassification is used as an intermediate step to find chemical parameters which are able to reclassify defined groups. These variables will be used in a next step where location and scale estimators of the groups are important. Traditionally linear discriminant analysis is used for reclassification which