Restoration 
Plantations and tree crop commodities 
Enhanced nutrition and food security 
Biodiversity, safeguarding and conservation 
Nationally determined contributions 
Bioenergy and biomaterials 
Blue carbon and peatlands 
Climate change adaptation 
Landscape governance 
Gender 
Silvopastoral systems 
Market-based agroforestry-forestry 
Farm-forest policy interface 
Agroecology 
Livelihood trajectory modelling and assessment 
Inclusive finance and business models 
Innovating finance for sustainable landscapes 
Public and private commitments to zero deforestation 
Orphan tree crops 
Effectiveness of approaches to sustainable supply 
Quality of FTA research for development 
Sentinel landscapes 
Foresight 
Seeds and seedlings delivery systems 
Smallholder tree-crop commodities 
Leaf area index (LAI), a measure of canopy density, is a key variable for modelling and understanding primary productivity, and also water use and energy exchange in forest ecosystems. However, LAI varies considerably with phenology and disturbance patterns, so alternative approaches to quantifying stand-level processes should be considered. The carbon isotope composition of soil organic matter (C-13(SOM)) provides a time-integrated, productivity-weighted measure of physiological and stand-level processes, reflecting biomass deposition from seasonal to decadal time scales. Our primary aim was to explore how well LAI correlates with C-13(SOM) across biomes. Using a global data set spanning large environmental gradients in tropical, temperate and boreal forest and woodland, we assess the strength of the correlation between LAI and C-13(SOM); we also assess climatic variables derived from the WorldClim database. We found that LAI was strongly correlated with C-13(SOM), but was also correlated with Mean Temperature of the Wettest Quarter, Mean Precipitation of Warmest Quarter and Annual Solar Radiation across and within biomes.Synthesis. Our results demonstrate that C-13(SOM) values can provide spatially explicit estimates of leaf area index (LAI) and could therefore serve as a surrogate for productivity and water use. While C-13(SOM) has traditionally been used to reconstruct the relative abundance of C-3 versus C-4 species, the results of this study demonstrate that within stable C-3- or C-4-dominated biomes, C-13(SOM) can provide additional insights. The fact that LAI is strongly correlated to C-13(SOM) may allow for a more nuanced interpretation of ecosystem properties of palaeoecosystems based on palaeosol C-13 values.
Authors:
Ladd, B.; Peri, P.L.; Pepper, D.A.; Silva, L.C.R.; Sheil, D.; Bonser, S.P,; Laffan, S.W.; Amelung, W.; Ekblad, A.; Eliasson, P.; Bahamonde, H.; Duarte-Guardia, S.; Bird, M.
Subjects:
canopy, carbon, soil organic matter, biomass production, climate change, ecosystems
Publication type:
ISI, Journal Article, Publication
Year:
2014
ISSN:
1365-2745
