Given prior evidence for local ecotypic and species-specific adaptation in trees, we hypothesized that: (1) Acer rubrum and Quercus rubra provenances with different climate origins should differ in photosynthetic temperature optimum (T opt ) even after long-term growth in a common environment; (2) congeneric species Populus tremuloides and Populus deltoides with differing but overlapping ranges should not differ in T opt when co-occurring, due to the likelihood of both ecotypic thermal adaptation and phenotypic thermal acclimation. To address these questions, we investigated the temperature responses of pairs of A. rubrum and Q. rubra provenances planted in a common garden and the temperature responses of P. tremuloides and P. deltoides at four sites where the species ranges overlap in Minnesota, USA. Both studies showed significant signals of temperature adaptation. The provenances of both A. rubrum and Q. rubra that originated from northern sites with lower ambient temperature had lower T opt . This supported the hypothesis about the dominance of local ecotypic adaptation of photosynthesis to temperature despite opportunity for both long-term (12-year) acclimation to the common-garden temperature regime and short-term temperature acclimation. However, acclimation capacity to the temperatures experienced in the days and weeks before the gas exchange measurements differed among the contrasting provenances suggesting that the observed differences in T opt could be due to either fixed genotypic differences (e.g., adaptive T opt ), acclimation of T opt , or both. In contrast, the Populus species with the colder home range, P. tremuloides, showed significantly (P \ 0.05) lower T opt on average than co-occurring P. deltoides. Thus, despite the opportunity for both ecotypic adaptation and local acclimation, phylogenetic inertia still constrained the species with the colder overall range to a different temperature optimum than the one with a warmer overall range. Our results also imply that rapid but modest climate change may create mismatches between photosynthetic physiology and local climate because of lags in population or species-level adaptation.Electronic supplementary material The online version of this article

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Efficient provenance storage is an essential step towards the adoption of provenance. In this paper, we analyze the provenance collected from multiple workloads with a view towards efficient storage. Based on our analysis, we characterize the properties of provenance with respect to long term storage. We then propose a hybrid scheme that takes advantage of the graph structure of provenance data and the inherent duplication in provenance data. Our evaluation indicates that our hybrid scheme, a combination of web graph compression (adapted for provenance) and dictionary encoding, provides the best tradeoff in terms of compression ratio, compression time and query performance when compared to other compression schemes.

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This paper presents results from a series of model tests of single vertical piles subjected to lateral monotonic pile head loading. Model tests were carried out in sand under a simulated field stress condition using the hydraulic gradient similitude technique. Studies were focused on examining various factors that affect the soil-pile interaction in terms of P–y curves. It was found that the P–y curves are highly nonlinear and stress-level dependent but are insensitive to the pile head loading conditions. The P–y curves at depths below one pile diameter were found to be normalized by the maximum soil Young's modulus Emax and the pile diameter. Comparison was made between the experimental P–y curves and those recommended by the American Petroleum Institute (API). It was found that the experimental P–y curves were significantly different from the API P–y curves. New procedures for constructing P–y curves are proposed and verified by numerical analyses of the observed model pile response. The results indicate that the API P–y curves based on a hyperbolic tangent function tend to overestimate the pile head stiffness, especially for fixed-head piles due to their stiffer shape in the small to medium pile deflection range. The proposed parabolic P–y curves can better resemble experimental P–y curves and consequently give a better prediction of pile response for both free- and fixed-head conditions. Finally, the proposed procedures were applied to analyze a full-scale pile load test, and good agreement was found between the predictions using the proposed parabolic P–y curves and the field test data. Key words : lateral loads, piles, model tests, sands.

Using the constituent elements of vulnerability, an evaluation index system for the ecological vulnerability of coastal areas under oil spill stress is established based on "Sensitivity-Adaptive Capacity-Exposure". After selecting a gulf in China as the main case study in this work, the cluster analysis and reference method were applied in grading and value assigning for all indexes. In addition, the analytic hierarchy process and expert evaluation method were used to determine the index weighting. Finally, a comprehensive evaluation method was adopted in the evaluation studies on the ecological vulnerability of the gulf coastal zone under oil spill stress. Results show the differences between the gulf area and areas that belong to different ecologically-vulnerable areas under oil spill stress.

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