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Accueil du site → Master → Etats Unis → 1971 → Effects of watering treatments on emergence of plant species in soil collected from different desert grassland sites

New Mexico State University (1971)

Effects of watering treatments on emergence of plant species in soil collected from different desert grassland sites

Aguirre EL.

Titre : Effects of watering treatments on emergence of plant species in soil collected from different desert grassland sites

Auteur : Aguirre EL.

Université de soutenance : New Mexico State University

Grade : Master of Science (MS) 1971

Résumé
Research reported herein was conducted to determine the emergence of plant species from surface soil collected on black grama (Bouteloua eriopoda) grassland sites in good, fair and poor range condition under various soil moisture levels. The species that emerged and their numbers were compared to the species actually found on the field locations. The potential plants per square meter, represented as viable seed in upper two cms of soil on a black grama range site under the field capacity moisture level, compared with seedlings which emerged in the field locations were, respectively : "fair condition" 993.1 and 103.8 ; "good condition" 409.7 and 87.4 ; "poor condition" 687.5 and 147.5. For the conditons of the present experiment, the following conclusions were drawn : 1) The black grama site in good range condition had less plant potential represented as buried seeds, for total numbers of species, than fair and poor conditions ; 2) There was no difference between fair and poor range conditions for total plants emerged ; 3) Fair condition had more buried grass seed potential than good or poor conditions ; 4) Poor condition had more buried seed potential than good condition, but the species were annuals or perennials of low grazing value ; 5) When black grama grass dominated a given plant community, emergence in greenhouse of seed potential did not reflect total (seedlings and mature plants) vegetation composition. But when seedling numbers alone were compared to the field location vs. emergence on the greenhouse, a fair idea of seed potential was obtained ; 6) Seedlings emerging in the greenhouse reflected the plants of the successsional stage actually sampled in the field locations ; 7) The same species emerged when water equivalent to 1-inch in rainfall (925cc) was applied as when the soil was maintained at field capacity ; 8) Fewer grass plants emerged when water equivalent to 1/2-inch rainfall (460cc) was applied than with 1-inch of water of field capacity ; 9) Water equivalent to 1/4-inch in rainfall (230cc) did not produce significant germination when applied once each four days, but when applied every two days, a significant increase in emergence was observed.

Mots Clés : germination, grassland species, grass, Bouteloua, germination, grass, seed,

Présentation (Jornada bibliography)

Page publiée le 24 mai 2016, mise à jour le 15 décembre 2017