Climatic reconstruction at the Miocene Shanwang basin, China, using leaf margin analysis, CLAMP, coexistence approach, and overlapping distribution analysis

Abstract

The reconstruction of the climate in the Miocene Shanwang basin is an important link in understanding past climate and environmental changes in East Asia. A recent study showed that the mean annual temperature (MAT) estimates derived from leaf margin analysis (LMA) and the Climate Leaf Analysis Multivariate Program (CLAMP) conflicted with and were remarkably lower than those estimated by the coexistence approach (CA). Overlapping distribution analysis (ODA), a new method introduced here, is used to reconstruct the Shanwang Miocene climate based explicitly on local plant distribution data and associated meteorological stations. The Shanwang flora (17-15.2 Ma) suggests a MAT of 10.9-14.5°C and a mean annual precipitation (MAP) of 1107.3-1880.0 mm. This result is closer to the values derived from CLAMP and LMA than that obtained by CA. This report is the first comprehensive intercomparison of foliar physiognomic and nearest living relative climate proxies in a Chinese context and provides important cross validation of results.

Refining CLAMP — Investigations towards improving the Climate Leaf Analysis Multivariate Program

“…Since CLAMP was first published by Wolfe (1993), a number of improvements to this method have been proposed (e.g., Kovach and Spicer, 1995;Stranks and England, 1997;Yang et al (2007), but not all of these improvements have been widely accepted. Stranks and England (1997) proposed the use of only ~20 modern sites that are physiognomically most similar to the fossil flora under investigation (nearest neighbours based on the Euclidean distance to determine temperature), in general an approach that is very similar to the procedure proposed by us, but based on different and more complicated mathematics.…”

“…Techniques for the quantitative reconstruction of palaeoclimatic conditions during the Cenozoic and the Cretaceous, in particular, have attracted a considerable amount of scientific interest. Although much work has been devoted to this kind of research, it has to be kept in mind that so far all methods and approaches have their own limitations and shortcomings and that perhaps there will never be an optimal, universally applicable and absolutely reliable technique for the quantitative estimation of palaeoclimatic parameters from fossil plants (e.g., Mosbrugger and Utescher, 1997;Wilf, 1997;Wilf et al, 1998;Wiemann et al, 1998;Uhl et al, 2007aUhl et al, , 2007bTraiser et al, 2005Traiser et al, , 2007Spicer et al, 2004;Spicer, 2000Spicer, , 2007Yang et al, 2007). This is largely due to complex spatial and temporal variations in the natural environment and plant adaptations that require finite time to equilibrate, and ultimately are compromise solutions to often conflicting environmental constraints (Spicer, 2007;Spicer et al, 2009).…”

Floristic composition and comparison of middle Eocene to late Eocene and Oligocene floras in North America

“…However, there continue to be more efforts to integrate both NLR and leaf physiognomic methods in a meaningful way and many studies incorporate a combination of approaches. One such effort recently proposed by Yang et al (2007) is Overlapping Distribution Analysis (ODA). This method uses both NLR and the MAT (of NLRs) methodologies, but is based on local plant distributions of living relatives and data from meteorological stations located in a determined area representing the region of overlap of the NLRs.…”

Palaeoclimate analysis of the flora of the Klikov Formation, Upper Cretaceous, Czech Republic

“…The Nearest Living Relative methods (Heer 1855-1859, Mosbrugger 1999 Wing & Greenwood 1993, Wilf 1997, Wilf et al 1998; and Climate Leaf Analysis Multivariate Program (CLAMP) (Wolfe 1990(Wolfe , 1993Spicer 2006;Yang et al 2007). CLAMP is a far more precise method for Cretaceous floras, because it does not require living relatives which are extremely uncommon for Cretaceous taxa.…”