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Our planet is facing a variety of serious threats from climate change that are unfolding unevenly across the globe. Uncovering the spatial patterns of ecosystem stability is important for predicting the responses of ecological processes and biodiversity patterns to climate change. However, the understanding of the latitudinal pattern of ecosystem stability across scales and of the underlying ecological drivers is still very limited. Accordingly, this study examines the latitudinal patterns of ecosystem stability at the local and regional spatial scale using a natural assembly of forest metacommunities that are distributed over a large temperate forest region, considering a range of potential environmental drivers. We found that the stability of regional communities (regional stability) and asynchronous dynamics among local communities (spatial asynchrony) both decreased with increasing latitude, whereas the stability of local communities (local stability) did not. We tested a series of hypotheses that potentially drive the spatial patterns of ecosystem stability, and found that although the ecological drivers of biodiversity, climatic history, resource conditions, climatic stability, and environmental heterogeneity varied with latitude, latitudinal patterns of ecosystem stability at multiple scales were affected by biodiversity and environmental heterogeneity. In particular, α diversity is positively associated with local stability, while β diversity is positively associated with spatial asynchrony, although both relationships are weak. Our study provides the first evidence that latitudinal patterns of the temporal stability of naturally assembled forest metacommunities across scales are driven by biodiversity and environmental heterogeneity. Our findings suggest that the preservation of plant biodiversity within and between forest communities and the maintenance of heterogeneous landscapes can be crucial to buffer forest ecosystems at higher latitudes from the faster and more intense negative impacts of climate change in the future. [ABSTRACT FROM AUTHOR]

Estimating forest above‐ground biomass (AGB) productivity constitutes one of the most fundamental topics in forest ecological research. Based on a 30‐ha permanent field plot in Northeastern China, we modeled AGB productivity as output, and topography, species diversity, stand structure, and a stand density variable as input across a series of area scales using the Random Forest (RF) algorithm. As the grain size increased from 10 to 200 m, we found that the relative importance of explanatory variables that drove the variation of biomass productivity varied a lot, and the model accuracy was gradually improved. The minimum sampling area for biomass productivity modeling in this region was 140 × 140 m. Our study shows that the relationship of topography, species diversity, stand structure, and stand density variables with biomass productivity modeled using the RF algorithm changes when moving from scales typical of forest surveys (10 m) to larger scales (200 m) within a controlled methodology. These results should be of considerable interest to scientists concerned with forest assessment. [ABSTRACT FROM AUTHOR]

Aim: Understanding the biodiversity–stability relationship has become a central issue in ecology and conservation biology. Although the stabilizing effects of tree species diversity on ecosystem productivity are well recorded in small local communities, they remain poorly understood across scales (from local to larger spatial scales). This study evaluates biodiversity–stability effects from local to larger spatial scales in a large temperate forest region, considering a range of environmental conditions and environmental heterogeneity. Location: North‐eastern China (c. 700,000 km2). Time period: 2005–2017. Major taxa studied: Woody plants. Methods: We define stability as the temporal invariability of biomass productivity. Regional metacommunities representing larger spatial scales were developed by aggregating multiple sets of local field plots. Simple regression analysis was used to test biodiversity–stability relationships in metacommunities. Piecewise structural equation modelling was then used to disentangle the effects of diversity and abiotic variables on forest stability at local and larger spatial scales. Multiple mixed‐effects regression models were used to determine the relative contribution of individual predictive variables to stability across spatial scales. Results: We found that local diversity (alpha diversity) was positively related to the stability of local communities (alpha stability), whereas species turnover across space (beta diversity) was positively related to asynchronous dynamics among local communities (spatial asynchrony), regardless of whether abiotic factors were considered or not. We also found that environmental conditions and environmental heterogeneity affected forest stability across scales. The effect of spatial asynchrony on gamma stability was greater than that of alpha stability. Main conclusions: Our results imply that spatial asynchrony is a key to maintaining the stability of ecosystem productivity within a large temperate forest region. We suggest that diverse forests and heterogeneous landscapes should be sustained at multiple spatial scales to buffer the negative effects of climate change and forest degradation. [ABSTRACT FROM AUTHOR]