1.        Lavergne, A., Daux, V.,Villalba, R., Pierre, M., Stievenard, M., & Srur, A. M. (2016). Improvementof isotope-based climate reconstructions in Patagonia through a betterunderstanding of climate influences on isotopic fractionation in tree rings.Earth and Planetary Science Letters.

Very few studies of stable isotopes existacross the Andes in South America. This study is the first presenting annuallyresolved chronologies of both δ18O and δ13C in Nothofagus pumilio and Fitzroyacupressoides   trees from NorthernPatagonia. Interannual variability in δ18O and δ13C was assessed over theperiod 1952–2011. Based on these chronologies, we determined the primary climaticcontrols on stable isotopes and tree physiological responses to changes inatmospheric CO2 concentrations (ca), temperature and humidity. Changes inspecific intrinsic water use efficiency (iWUE) were inferred from variations inδ13C whereas the effects of CO2 increase on stomatal conductance were exploredusing δ18O. Over the 60-year period, iWUE increased significantly (by ca. 25%)in coincidence with the rise of ca. The two species appear to have differentstrategies of gas-exchange. Whereas iWUE variations were likely driven by bothstomatal conductance and photosynthetic assimilation rates in F. cupressoides,they were largely related to stomatal conductance in N. pumilio  . After removing the low-frequency trendsrelated to increasing ca, significant relationships between δ13C and summertemperatures were recorded for both species. However, δ13C variations in F.cupressoides were more strongly influenced by summer temperatures than in N.pumilio. Our results advocate for an indirect effect of summer temperatures onstable isotope ratios, which is mostly influenced by sunlight radiation in F.cupressoides and relative humidity/soil moisture in N. pumilio  . δ13C variations in F. cupressoides   were spatially correlated to a large areasouth of 35°S in southern South America. These promising results encourage theuse of δ13C variations in F. cupressoides for reconstructing past variations intemperature and large-scale circulation indexes such as the Southern AnnularMode (SAM) in the Southern Hemisphere.

http://www.sciencedirect.com/science/article/pii/S0012821X16306793/pdfft?md5=8c2de405037edc858e64548a433b4529&pid=1-s2.0-S0012821X16306793-main.pdf

2.        Friesen, J., Sinobas, L. R.,Foglia, L., & Ludwig, R. (2016). Environmental and socio-economicmethodologies and solutions towards integrated water resources management.

Semi-arid regions are facing the challengeof managing water resources under conditions of increasing scarcity anddrought. These are recently pressured by the impact of climate change favoringthe shifting from using surface water to groundwater without taking sustainabilityissues into account. Likewise, water scarcity raises the competition for wateramong users, increasing the risk of social conflicts, as the availability offresh water in sufficient quality and quantity is already one of the majorfactors limiting socio-economic development.

In terms of hydrology, semi-arid regionsare characterized by very complex hydro- and hydrogeological systems. Thecomplexity of the water cycle contrasts strongly with the poor dataavailability, (1) which limits the number of analysis techniques and methodsavailable to researchers, (2) limits the accuracy of models and predictions,and (3) consequently challenges the capabilities to develop appropriatemanagement measures to mitigate or adapt the environment to scarcity anddrought conditions.

Integrated water resources management is aholistic approach to focus on both environmental as well as on socio-economicfactors influencing water availability and supply. The management approachesand solutions adopted, e.g. in form of decision support for specific waterresources systems, are often highly specific for individual case studies.

http://www.sciencedirect.com/science/article/pii/S0048969716327383/pdfft?md5=2e9c81b4ae8a6bda6def14876adeecaf&pid=1-s2.0-S0048969716327383-main.pdf

3.        Shi, J., Li, J., Zhang, D. D.,Zheng, J., Shi, S., Ge, Q., ... & Lu, H. (2016). Two centuries ofApril-July temperature change in southeastern China and its influence on grainproductivity. Science Bulletin.

China is a traditional agriculture basedcountry and one main region for crop production is southeastern China wheretemperature is a dominant climate variable affecting agriculture. Temperatureand social disturbances both influence crop production, yet distinguishingtheir relative impacts is difficult due to a lack of reliable, high-resolutionhistorical climatic records before the very recent period. Here we present thefirst tree-ring based warm-season temperature reconstruction for southeasternChina, a core region of the East Asian monsoon, for the past 227 years. Thereconstruction target was April-July mean temperature, and our model explained60.6% of the observed temperature variance during 1953–2012. Spatialcorrelation analysis showed that the reconstruction is representative ofApril-July temperature change over most of eastern China. The reconstructedtemperature series agrees well with China-scale (heavily weighted in easternChina) agricultural production index values quite well at decadal timescales.The impacts of social upheavals on food production, such as those in the period1920–1949, were confirmed after climatic influences were excluded. Our studyshould help distinguish the influence of social disturbance and warm-seasontemperature on grain productivity in the core agricultural region of Chinaduring the past two centuries.

http://www.sciencedirect.com/science/article/pii/S2095927316305679/pdfft?md5=8d0ac949a981452fafa9c5cba1361327&pid=1-s2.0-S2095927316305679-main.pdf

4.        Haasan, M. (2016). Tree-ringgrowth modelling applied to Bayesian dendrochronology (Doctoral dissertation,University of Sheffield).

Classical dendrochronology involves usingstandard statistical methods, such as correlation coefficients and t-values tocrossmatch undated tree-ring width sequences to dated 'master' chronologies.This crossmatching process aims to identify the 'best' offset between the datedand undated sequences with a view to providing a calendar date estimate for theundated trees. Motivated by the successful and routine use of Bayesianstatistical methods to provide a fully probabilistic approach to radiocarbondating, this thesis investigates the practicality of using a process-basedforward model known as 'VSLite' at the core of Bayesian dendrochronology. Themechanistic VSLite model has the potential to capture key characteristics ofthe complex system that links climate to tree-ring formation. It allowssimulated, dated tree-ring chronologies to be generated at any geographicallocation where historical climate records exist. Embedding VSLite within aBayesian approach to tree-ring dating allows combination of both ring-widthdata and any available prior information. Additionally, instead of identifyingthe `best' calendar date estimate, the Bayesian approach allows provision ofprobabilistic statements about a collection of possible dates, each with a specific(posterior) probability. The impact of uncertainty in the VSLite inputparameters on the model output has been systematically investigated in thisthesis, and the VSLite-based approach to Bayesian tree-ring dating has beenexplored using both simulated and real data. Results of implementing the newVSLite-based approach are compared with those using current classical andBayesian approaches. An option for reducing the need for preprocessing data isalso investigated via a data-adaptive rescaling approach. Having establishedthe effectiveness of using the mechanistic forward model as the core forBayesian dendrochronology, the practicality of adopting it to aid in dating inthe absence of suitable local master chronologies is also explored.

http://etheses.whiterose.ac.uk/15746/1/PhD_Thesis_Masoud_Hassan_2016.pdf

5.        Gea‐Izquierdo,G., Nicault, A., Battipaglia, G., Dorado‐Liñán, I., Gutiérrez, E.,Ribas, M., & Guiot, J. (2016). Risky future for Mediterranean forestsunless they undergo extreme carbon fertilization. Global Change Biology.

Forest performance is challenged by climatechange but higher atmospheric [CO2] (ca) could help trees mitigate the negativeeffect of enhanced water stress. Forest projections using data-assimilationwith mechanistic models are a valuable tool to assess forest performance.Firstly, we used dendrochronological data from 12 Mediterranean tree species (6conifers, 6 broadleaves) to calibrate a process-based vegetation model at 77sites. Secondly, we conducted simulations of gross primary production (GPP) andradial growth using an ensemble of climate projections for the period 2010-2100for the high-emission RCP8.5 and low-emission RCP2.6 scenarios. GPP and growthprojections were simulated using climatic data from the two RCPs combined with:(i) expected ca; (ii) constant ca = 390 ppm, to test a purely climate-drivenperformance excluding compensation from carbon fertilization. The modelaccurately mimicked the growth trends since the 1950s when, despite increasingca, enhanced evaporative demands precluded a global net positive effect ongrowth. Modeled annual growth and GPP showed similar long-term trends. UnderRCP2.6 (i.e. temperatures below +2°C with respect to preindustrial values) theforests showed resistance to future climate (as expressed by non-negativetrends in growth and GPP) except for some coniferous sites. Using exponentiallygrowing ca and climate as from RCP8.5, carbon fertilization overrode thenegative effect of the highly constraining climatic conditions under thatscenario. This effect was particularly evident above 500 ppm (which is alreadyover +2°C), which seems unrealistic and likely reflects model miss-performanceat high ca above the calibration range. Thus, forest projections under RCP8.5preventing carbon fertilization displayed very negative forest performance atthe regional scale. This suggests that most of western Mediterranean forestswould successfully acclimate to the coldest climate change scenario but bevulnerable to a climate warmer than +2°C unless the trees developed anexaggerated fertilization response to [CO2].

http://onlinelibrary.wiley.com/doi/10.1111/gcb.13597/epdf

6.        Kueppers, L. M., Conlisk, E.,Castanha, C., Moyes, A. B., Germino, M. J., Valpine, P., ... & Mitton, J.B. (2016). Warming and provenance limit tree recruitment across and beyond theelevation range of subalpine forest. Global Change Biology.

Climate niche models project that subalpineforest ranges will extend upslope with climate warming. These projectionsassume that the climate suitable for adult trees will be adequate for forestregeneration, ignoring climate requirements for seedling recruitment, apotential demographic bottleneck. Moreover, local genetic adaptation isexpected to facilitate range expansion, with tree populations at the upperforest edge providing the seed best adapted to the alpine. Here, we test theseexpectations using a novel combination of common gardens, seeded with twowidely distributed subalpine conifers, and climate manipulations replicated atthree elevations. Infrared heaters raised temperatures in heated plots, butraised temperatures more in the forest than at or above treeline because strongwinds at high elevation reduced heating efficiency. Watering increasedseason-average soil moisture similarly across sites. Contrary to expectations,warming reduced Engelmann spruce recruitment at and above treeline, as well asin the forest. Warming reduced limber pine first-year recruitment in theforest, but had no net effect on fourth-year recruitment at any site. Wateringduring the snow-free season alleviated some negative effects of warming,indicating that warming exacerbated water limitations. Contrary to expectationsof local adaptation, low-elevation seeds of both species initially recruitedmore strongly than high-elevation seeds across the elevation gradient, althoughthe low-provenance advantage diminished by the fourth year for Engelmannspruce, likely due to small sample sizes. High- and low-elevation provenancesresponded similarly to warming across sites for Engelmann spruce, butdifferently for limber pine. In the context of increasing tree mortality, lowerrecruitment at all elevations with warming, combined with lower quality,high-provenance seed being most available for colonizing the alpine, portendsrange contraction for Engelmann spruce. The lower sensitivity of limber pine towarming indicates a potential for this species to become more important insubalpine forest communities in the coming centuries.

http://onlinelibrary.wiley.com/doi/10.1111/gcb.13561/epdf