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Recent studies have raised concerns regarding the reconstruction of glacier mass balance using tree-ring data. The method relies on a stable relationship between both variables and summer (June–August) or melt season (May–September) temperature. However, with recent anthropogenic climate change the stability of this relationship is challenged by both, a divergence between tree-ring and temperature, as well as mass balance and temperature data. Establishing to what extent this divergence influences the reconstruction of mass balance using tree-ring data is important to assess the future viability and applicability of the method. In this paper we analyze the relationship between the Torneträsk tree-ring and Storglaciären mass balance records, their response to climate change, and investigate changes in the relationship. We provide evidence for a sensitivity loss in the Torneträsk record and quantify its impact on the reconstruction of summer mass balance of Storglaciären. We find that by including years post 1980, the amplitude of reconstructed variability is reduced, but it remains possible to explain the variance of the record significantly. Our results suggest that for glaciers without an extensive mass balance record the applicability of the method is challenged. [ABSTRACT FROM AUTHOR]

The Asian Alpine Belt (AAB) region extends from the Tibetan Plateau to the Caucasus. Rapid climate change and increasing anthropogenic pressures in the ecologically sensitive alpine area are making the achievement of sustainable development goals in the AAB more challenging. The water--food--energy--ecosystem (WFEE) nexus describes the trade-offs and synergies among the various elements of water, food, energy resources, and natural ecosystems relevant for sustainable development. The optimization of the WFEE nexus in the AAB region has become a vital issue for reaching sustainability in this ecologically fragile Eurasian region and its developing countries. In this paper, we broadly classify research into four types based on a compilation of recent research on the WFEE nexus in the AAB region: ecohydrological processes, agriculture and livestock, clean energy, and local social adaptation. We use the classification--coordination--collaboration approach to build an optimized conceptual framework to indicate a future research path. The outlook includes enhanced identification of the WFEE nexus, scientifically rational decision-making, and attention to cross-sector and transnational collaboration to support the realization of sustainable development goals in the AAB region. [ABSTRACT FROM AUTHOR]

Quantifying the relative influences of anthropogenic activities and climate change on soil erosion and deposition during the Holocene, when both forces have been interacting is a complex problem. Analysis of long-term patterns in soil erosion and lake deposition in a basin can provide the basis for untangling the complexities of climate and anthropogenic forcings. In this paper, sedimentary sequences from Xingyun Lake are compared with simulated soil erosion rates in the basin to explore the relationship between river basin soil erosion and lake deposition during the Holocene in Yunnan, China. Modern soil erosion rates are calculated using RUSLE, while Holocene soil erosion rates are estimated using modern rates with reconstructed precipitation and vegetation cover sequences. Through this investigation, we found the following results. First, Holocene vegetation in the lake basin was mainly affected by climate change, and the vegetation experienced the same pattern of changes as the climate. Soil erosion and lake deposition rates, along with changes to vegetation cover, were synchronous with precipitation trends during the Holocene. Second, soil erosion and lake deposition have been exacerbated by human activities, such as deforestation and land reclamation in the Xingyun Lake basin. Finally, this study provides new insights into the effects by anthropogenic impacts and climate forcing on the processes of soil erosion and lake deposition on the millennium scale. [ABSTRACT FROM AUTHOR]

This paper examines the hypothesis that human landscape modifications involving early agriculture contributed to greenhouse gas emissions in preindustrial times, a proposal that has significant implications for the timing of the Anthropocene era. In synthesizing recent papers that both advocate and challenge this hypothesis, we identify a major bias in the ongoing debate, which focuses on the land clearance practices of agrarian people, with insufficient consideration of a diverse range of hunter-gatherer societies who regularly utilized landscape-scale burning for various purposes. Employing California as a case study, we examine how the exclusion of hunter-gatherers from this debate may have shortchanged estimates of human biomass burning in preindustrial times. We also suggest that human population size may be a poor proxy for the degree of land clearance and anthropogenic burning, and we describe how previous approaches to these questions may have underplayed the importance of variation in the timing and magnitude of depopulation in different regions of the Americas. [ABSTRACT FROM AUTHOR]

This paper is based on a multidisciplinary study using both paleoenvironmental methods (biological, sedimentological, magnetic and geochemical) and archaeological data in order to characterize landscape and hydrological network changes as well as human impact on a littoral catchment in the Western Mediterranean area. Sedimentary records obtained around a coastal alluvial plain (Cassis, Southeastern France) reveal local environmental changes and human activities since the Neolithic (ca. 6000 cal. BP). Anthropogenic impact is already noticeable in the earliest record, and we follow its evolution through time. According to biological markers, the Holocene landscape of the Calanques is dominated by a mosaic of open herbaceous formations partly generated by human activity. The prevalence of Cernuella virgata in malacofauna successions and of coprophilous fungal spores in the pollen record testifies to the spread of agro-pastoral activities. Two increases of anthropogenic impact are highlighted during the Roman (ca. 2000 cal. BP) and Modern (from ca. 1450 to today) periods. Lead isotope analyses indicate an anthropogenic release of lead, possibly originating from the Greek Cyclades (ca. 2000 cal. BP). Hydrographic and agricultural work is also enhanced during the Roman period. Magnetic parameters and lead isotopes indicate that the Modern anthropogenic impact may be associated with high temperature activities (e.g. lime kiln, fossil fuel). [ABSTRACT FROM AUTHOR]

Discharge from the largest karst spring in north China, the Niangziguan Springs, has been declining since the 1950s. This paper examines the response of these springs to climatic change and anthropogenic influence by attempting a model-based discrimination between phases in the stream discharge record. In Niangziguan Springs Basin, the exploitation of karst groundwater began in 1979. Accordingly, the spring discharge data were divided into two phases: pre-1979 and post-1979. In the first phase (1957-78) the spring discharge was believed to be affected solely by climate change, and in the second phase (1979-2007) the spring discharge was influenced by both climate change and human activities. Using grey system theory, a discharge model was estimated for the first phase. Extrapolating the model, we obtained a projection of the spring discharge during the second phase. Using a water balance calculation, we discerned the respective effects of climate change and human activities on depletion of spring discharge for the second phase. The results show that the contribution of climate change to depletion of Niangziguan Springs is 2.30m3/s and the contribution of anthropogenic activities ranges from 1.89 to 2.90 m3/s, although this assumes a constant for the climate change effect. Accordingly, the anthropogenic effects have been approaching and surpassing the effects of climate change during the second phase. With respect to the impact of human activities on spring discharge, groundwater abstraction accounts for only about 34-52% of the declines; 48-66% of the declines are related to other human activities, such as dewatering from coal mining, dam building and deforestation. [ABSTRACT FROM AUTHOR]

This paper interprets macroscopic charcoal (>250 μm), humification and loss-on-ignition over the last ∼14 200 cal. BP from Goochs Swamp, located to the west of Sydney in the Greater Blue Mountains World Heritage Area. This study aimed to investigate relationships between humans, climate and fire through time, primarily by comparison of these palaeoenvironmental indices with archaeological evidence from the region. Climatic forcing can explain all periods of change in the history of fire at Goochs Swamp: fire activity was variable during the Lateglacial-Holocene transition, low during the relatively stable climate of the early Holocene, and high but variable after the onset of modern El Niño from the mid Holocene. Although the dominant control on fire in this environment during the Holocene appears to be climate, fluctuations in the late Holocene may reflect anthropogenic fire or human responses to climate change. The archaeological record of the Blue Mountains and other parts of the Sydney Basin illustrates that Aboriginal people altered subsistence, resource and land-use patterns in the late Holocene. We propose that these cultural measures were adopted to overcome new risks as the frequency of ENSO events increased, and the natural fire regime and resource reliability changed. These strategies perhaps included a more systematic use of fire. The most parsimonious interpretation of the evidence for changes in fire activity at Goochs Swamp in the light of nearby archaeological evidence is that Aboriginal people used fire within a changing climatic framework. [ABSTRACT FROM AUTHOR]