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There is an urgent need to examine the range of ecosystems that is currently protected in national parks and reserves, to point out those examples that are unprotected and to establish a rational programme of priorities for protecting as complete a series as possible. The International Biological Programme has pioneered the field of large-scale survey work for the collection of data of relevance to this need and has contributed to the development of information retrieval techniques for handling the data. The first part of the paper discusses the rationale of the development of the data base and its modus operandi. The system is illustrated by two examples of retrieval and analysis for specific enquiries; the distribution of four species of Pinus, and the occurrence of grazing, logging and burning in national parks and equivalent reserves in the United States. The second part of the paper deals with system design, details of programming for the data base, and retrieval strategy. It is intended as an independent section which may be skipped if the reader has no interest in the finer points of the data base itself. [ABSTRACT FROM AUTHOR]

Two isolates of the ectomycorrhizal fungus Pisolithus tinctorius (Pers.) Coker and Couch were inoculated on to roots of Eucalyptus urophylla S. T. Blake in vitro and a comparison made of the rate of ectomycorrhizal development. Both isolates initiated ectomycorrhizal roots hut the rime of onset of root colonization and the rate of formation varied with the isolate An isolate cultured from a sporocarp collected from under eucalypts in Australia rapidly colonized roots of E. urophylla and initiated mycorrhizas after 2 d incubation, whereas an isolate obtained from sporocarps collected from under pines in the United States developed ectomycorrhizas only after 7 d incubation. Dual inoculation of E. urophylla seedlings using a paper-sandwich technique again showed the rapid colonization of roots by the eucalypt isolate even when roots were inoculated 7 d previously with the pine isolate. These in vitro observations support field observations that there are variable degrees of plant species - fungal isolate compatibility, implying specificity, and this is an important factor influencing successful ectomycorrhiza formation and development. [ABSTRACT FROM AUTHOR]

The article discusses the acetylene reduction in relaxation to levels of phosphate and fixed nitrogen in Green Bay. This paper reports data collected during the summer of 1971 in the southern part of Green Bay of Lake Michigan. This study undertook to characterize acetylene reduction and nutrient levels throughout the summer. Water samples were collected. Phytoplankton characteristically increase rapidly in the spring. A high soluble phosphate concentration in the water preceded all major increases in the population of heterocystous, nitrogen-fixing blue-green algae.