Consequences of altered precipitation, warming, and clipping for plant productivity, biodiversity, and grazing resources at three northern temperate grassland sites
Notice bibliographique
Résumé
There is limited understanding about how altered precipitation and warming associated with climate change affect grassland systems. Also, although grasslands commonly support herbivores, it is unclear how grazing influences responses to climate change. To address these knowledge gaps, I carried out a fully controlled and factorial three-year, multi-site experiment simulating climate change and grazing (via clipping). This experiment was conducted at three sites, chosen to broadly represent northern temperate grassland in the region, and each of Canada’s prairie provinces. I increased air temperature by 2-4°C, reduced precipitation by 60%, and clipped plants at low and high intensity. At one site, I also applied added (+60%) precipitation. I monitored an array of responses, including plant biomass and biodiversity, and grazing resources. Shoot biomass decreased strongly with reduced precipitation and clipping, and tended to decrease with warming. However, shifts in root: shoot ratio and associated root biomass responses enabled stability of total biomass. With respect to grazing resources, herbage availability and quality decreased with reduced precipitation and warming; decline in herbage availability was less pronounced with warming than reduced precipitation. To assess biodiversity responses, I evaluated indirect and direct treatment effects on species richness and evenness. Across sites, richness declined with environmental changes associated with all three treatments. However, evenness responses varied by site, and were overall more resistant. I also assessed changes in similarity between the seed bank and aboveground vegetation at one location. Precipitation and clipping affected similarity between the seed bank and vegetation, while warming did not. Across sites, responses were generally consistent, except for the driest site, which remained largely resistant to reduced precipitation. Generally, the grasslands were highly responsive to warming, altered precipitation, and clipping, with negative implications for ecosystem function and biodiversity. However, productivity and biodiversity responses were asynchronous; productivity was more responsive to precipitation and clipping, while richness was more sensitive to increased air temperature. As well, results suggest that management will not substantially influence responses to climate change. Overall, maintenance of total biomass suggests that ecosystem function is relatively resistant to climate change, but climate change has negative ramifications for biodiversity and grazing resources.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,001 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,000 | 0,000 |
| Études des sciences et des technologies | 0,001 | 0,001 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,001 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,001 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,001 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule source (Gemma direct ou Codex distillé), pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».