Available online
Description
This programme describes various methods of sampling small animals from grassland vegetation and from the soil. Insects are collected from grassland with the help of a vacuum sampler which sucks in...sects into a collecting bag in a hoover like fashion. Two methods of extracting small soil animals from core samples of agricultural soil are described. The first relies on active movement by animals through physical gradients of temperature, humidity and light: the second involves a passive separation of animals from soil by flotation and differential wetting. The programme concludes by introducing the statistical treatment of ecological samples.
This programme describes various methods of sampling small animals from grassland vegetation and from the soil. Insects are collected from grassland with the help of a vacuum sampler which sucks in...sects into a collecting bag in a hoover like fashion. Two methods of extracting small soil animals from core samples of agricultural soil are described. The first relies on active movement by animals through physical gradients of temperature, humidity and light: the second involves a passive separation of animals from soil by flotation and differential wetting. The programme concludes by introducing the statistical treatment of ecological samples.
| Module code and title: | S323, Ecology |
|---|---|
| Item code: | S323; 04; 1975 |
| First transmission date: | 04-04-1975 |
| Published: | 1975 |
| Rights Statement: | |
| Restrictions on use: | |
| Duration: | 00:24:00 |
| + Show more... | |
| Producer: | Jim Stevenson |
| Contributors: | Neil Chalmers; Jim Newman; Walter Wilkinson; Mike Morris |
| Publisher: | BBC Open University |
| Keyword(s): | Agricultural soil; Core samples; Grassland; Humidity; Physical gradients of temperature; Sampling; Small animals; Soil; Statistics; Vacuum sampler |
| Footage description: | Film shots of leaf hoppers. Jim Newman introduces the programme. Film shots of Mike Morris using a vacuum sampler to collect leaf hoppers in the field. Commentary by Jim Newman explains the technique. Shots of the catch being sieved in the laboratory to sort out the rubbish. Shots of specimen being counted. Commentary by Newman. Newman explains a method for sampling small soil animals. Film shots of soil core samples being taken with a power assisted corer. Newman, in the laboratory, demonstrates the technique of separating animals from soil samples using the McFadion High Gradient Extraction Apparatus. He explains how the apparatus works as he demonstrates and points out some of the deficiencies of this technique. Newman, in the laboratory, demonstrates the techniques of wet sieving and differential floatation for separating organic fractions from the soil. He explains the method as he goes along. Walter Wilkinson, in the laboratory, demonstrates and explains the differential wetting technique for separating animal from plant life in the organic fraction obtained above. Newman demonstrates a counting procedure using a counting sieve and microscope. He explains what he is doing each step of the way. Results of a sampling experiment are shown on a bar graph. Newman explains the data and results. Neil Chalmers uses a hypothetical example of an experiment on insecticide efficiency to explain some statistical treatments of ecological samples. He introduces and explains some elementary statistical techniques such as arithmetic mean, variance, standard deviation and some statistical notations. Animated captions are used throughout this sequence. |
| Master spool number: | 6HT/71754 |
| Production number: | 00525_1190 |
| Videofinder number: | 1028 |
| Available to public: | no |
