Available online
Description
This programme examines the characteristics of grass and cereal ecosystems.
This programme examines the characteristics of grass and cereal ecosystems.
| Module code and title: | S323, Ecology |
|---|---|
| Item code: | S323; 15 |
| First transmission date: | 24-09-1974 |
| Published: | 1974 |
| Rights Statement: | |
| Restrictions on use: | |
| Duration: | 00:23:53 |
| + Show more... | |
| Producer: | Neil Cleminson |
| Contributors: | Dick Morris; G. R. Potts |
| Publisher: | BBC Open University |
| Keyword(s): | Cereal crops; Early photographs; Fertilizers; Food chain; Gramineae; Herbage grasses; Herbicides; Partridges; Rice; Rothamsted Experimental Station |
| Footage description: | Shots of the Broadbalk Wilderness experiment during the 19th century. Shot of wheat field taken in 1882 and another shot of the same field in 1886 after 4 years without cultivation. R.M. Morris introduces the programme. He shows a series of photographs which give a record (incomplete) of the Broadbalk Wilderness experiment. This shows that over the past 80 years, the area has changed from a wheat field to a mature woodland. Richard Morris discusses the importance and extent of grassland and cereal areas in Britain. Several photographs aid. Morris examines several species of grasses in the studio. He points out their characteristic features. Morris restricts himself mainly to U.K. grasses. Morris uses a model of a grass to show the reason for its regenerative capability after being cut (as by grazing animals). He also shows an electron micrograph of the stem base area of a grass to amplify his argument. Morris, in the studio, next examines several examples of cereals, mainly British (oats, barley, wheat and rice). He points out their characteristic features. Morris rubs wheat seeds between his hands to demonstrate how starch is removed from wheat seeds. Shots of wheat being harvested. Shots of a field being plowed using a horse drawn plough. Shots of a root crop being harvested. Shots of grass being harvested for hay. The above shots illustrate the commentary which describes the 'classic' Norfolk four course rotation. Commentary by Morris. Shots of cattle being fed in stalls. Shots of fields being sprayed, from a tractor, with a selective herbicide to remove charlock, corn poppy and corn cockle. Shots of large modern machines harvesting a cereal crop. Shots of stubble being burned in the fields. Shots of aerial herbicide spraying. Morris, with an 1890-1970 wheat yield histogram, demonstrates the effect of selective herbicides and fertilisers on cereal production system. Shots of grey part ridges in the wild. Commentary by Morris discusses the effect of intensive cereal production, through use of herbicides and fertilisers, on the grey partridge population. He describes the habits of these birds as he does so. Dick Notts, Game Conservancy, discusses his research on the population dynamics of the grey partridge. He shows a graph which quantifies the number of kills from 1880 to 1970. This provides a sensitive index to total partridge population. The graph shows a dramatic drop in kills in the late 1960s. Potts uses a graph to correlate spring (March-May) temperatures with partridge chicks survival rate. (Temperature in the spring determines insect abundance later in the year). He concludes that pesticides have lowered the general level of insect numbers and thereby the partridge chick population which feeds off them. Potts correlates saw fly larvae population with partridge chick population. |
| Master spool number: | 6HT/71524 |
| Production number: | 00525_1135 |
| Videofinder number: | 1039 |
| Available to public: | no |
