Landscapes in the Anthropocene: State of the art and future directions

Landscapes in the Anthropocene: State of the art and future directions

Anthropocene 6 (2014) 1–2 Contents lists available at ScienceDirect Anthropocene journal homepage: www.elsevier.com/locate/ancene Preface Landscap...

218KB Sizes 7 Downloads 36 Views

Anthropocene 6 (2014) 1–2

Contents lists available at ScienceDirect

Anthropocene journal homepage: www.elsevier.com/locate/ancene

Preface

Landscapes in the Anthropocene: State of the art and future directions

Introduction In the last few years, a new geological epoch, the Anthropocene, has been the object of progressively intense discussions in both the scientific community, and more widely in the popular media. The scientific community is debating the proposition that we are now living in the Anthropocene (Zalasiewicz et al., 2008, 2011; Zalasiewicz, 2013), where human activities leave a significant, if not dominant, signature on Earth. These activities are expected to alter Earth’s topography, climate, ecosystems, and associated earth surface processes (Brown et al., 2013a). Anthropogenic landscapes now cover great extents of Earth’s land surface (Achard et al., 2002; Ellis, 2004; Foley et al., 2005; Tarolli, 2014). In such landscapes, direct human disturbance of surface morphology and processes is significant (Ellis et al., 2006; Ellis, 2011; Vanacker et al., 2014). The progressive increase of intensive farming, industrialisation and urbanization has transformed the natural landscapes by changing topography, vegetation cover, soil physical and chemical properties and soil water balances; thereby inducing major changes in sediment and nutrient retention and export along the hillslopechannel continuum (Tarolli et al., 2014). Recently, various studies (e.g. Liu et al., 2007; Chin et al., 2014) have pointed to the importance of coupled human-landscape dynamics, where changes in landscape functioning affect human systems. The analysis of human-landscape interactions in anthropogenic landscapes represents a real challenge for better understanding the evolution of our present-day environment. This analysis can contribute to steering integrated environmental planning towards sustainable development. Objective of this special issue This special issue brings together studies where the effects of human disturbances on Earth surface processes are quantified? The idea for this issue arose from a session convened by the authors during the European Geoscience Union General Assembly 2013, held in Wien, Austria. The two oral and one poster sessions attracted 30 abstracts on human-landscapes interactions. This special issue includes 8 papers drawn from the conference session. The variety of papers is illustrative for the diversity of methodological approaches in this research field, and exemplifies the extent and impact of human activities on landscapes. Overview of the papers presented Zalasiewicz et al. (2014), in their overview article, highlight the phenomenon of bioturbation by humans (‘anthroturbation’), ranging from surface landscaping to boreholes that penetrate deep into the crust. This phenomenon is without precedent in Earth http://dx.doi.org/10.1016/j.ancene.2014.11.003 2213-3054/ß 2014 Elsevier Ltd. All rights reserved.

history, being orders of magnitude greater in scale than any preceding non-human type of bioturbation. It can range from simple individual structures to complex networks that extend to several kilometers depth, while the extraction of material from underground can lead to topographic subsidence or collapse, with concomitant modification of the landscape. Tarolli et al. (2014) review the current state of terraced agricultural landscapes, thereby underlining critical issues with respect to land management and possible solutions. Three cases are presented in detail: Cinque Terre area (Liguria, Northern Italy), Chianti Classico area (Tuscany, Central Italy), and Amalfi Coast (Salerno, Southern Italy). Macklin et al. (2014) present a meta-analysis of 14C-dated Holocene anthropogenic alluvium in the UK. They suggest that the earliest environmental impacts of human activities on fluvial systems are observed on the hydrological rather than the sedimentological properties. The mediaeval period is confirmed as important with accelerated sedimentation of fine-grained materials, notably in the smallest catchments, as has also been shown by Brown et al. (2013b). Garbarino et al. (2014) examine forest stand structure and composition at the landscape scale in the Sagarmatha National Park and its Buffer Zone in the Khumbu valley (Nepal) to understand human interactions with forest resources. Using biological and historical data sources, a multi-scale approach revealed the influence of human activities on the distribution of tree species and forest structure. Sofia et al. (2014) analyze the modification of artificial drainage networks during the past half-century (from 1955 to 2006) in a reclamation area in the Veneto floodplain (Italy). The effects of the network transformations are quantified using a Network Saturation Index representing how fast an area is saturated by a design rainfall. Valese et al. (2014) present a review on fire, humans and landscape in the European Alpine region during the Holocene. Negative and positive impacts of current fire regimes on ecosystem services in the Alps are described, as well as the incidence of human fire uses and fire suppression policies. The authors also discussed the present and future strategies for fire management for the Alps. Guns and Vanacker (2014) use landslide frequency-area distributions to assess the potential impact of anthropogenic disturbances on landslide denudation. They quantify anthropogenic disturbances through historical land cover analyses. Their data on the Tropical Andes show that human disturbances significantly alter the landslide frequency – area distributions. Human-induced land cover change is associated with an increase of the total number of landslides and a shift of the frequency – area distribution towards smaller landslides.

2

Preface / Anthropocene 6 (2014) 1–2

Madricardo and Donnici (2014) reconstructed past and recent landscapes of the Venice Lagoon, extending from the period before its formation up to present day. The analyses were based on geophysical surveys and historical maps. Using radiocarbon dating and acoustical sub-bottom reconstruction, the authors mapped a dense network of palaeochannels corresponding to different hydrologic conditions. Results show that the number of channels has decreased substantially over the past centuries. This reduction was due to natural processes, such sea level rise and natural subsidence, as well as human activities, such as artificial diversion of rivers and modification of the inlets. Concluding remarks and future directions This special issue contributes to the growing insight and understanding of how human activities have altered different landscapes at a variety of spatial and temporal scales. The resulting signature on the landscape with direct consequences on processes and ecosystems can extend beyond the area of direct impact. This signature, often cumulative over time, is irreversible, and may persist after direct human forcing has stopped. The recognition and analysis of these human-induced signatures could help to improve environmental planning, and should be considered in the development of different measures for the mitigation of humaninduced environmental change. Future directions should follow this line that probably represents one the most interesting challenges of this century, not only for the Earth science community, but also for society. Acknowledgments We would like to thank the authors of the papers for their contribution to the EGU 2013 session and to this Special Issue, and all the reviewers involved. We are also grateful to the Editor in Chief Anne Chin, and James Timothy Horscroft for both their support and help. References Achard, F., Eva, H.D., Stibig, H.J., Mayaux, P., Gallego, J., Richards, T., 2002. Determination of deforestation rates of the world’s humid tropical forests. Science 297, 999–1002. Brown, A.G., Tooth, S., Chiverrell, R., Rose, J., Thomas, D.S.G., Wainwright, J., Bullard, J., Thorndycraft, V., Aalto, R., Downes, P., 2013a. The Anthropocene: is there a geomorphological case? Earth Surf. Process. Landf. 38, 431–434. Brown, A.G., Toms, P., Carey, C., Rhodes, E., 2013b. Geomorphology of the Anthropocene: time-trangressive discontinuities of human-induced alluviation. Anthropocene 1, 3–13. Chin, A., Florsheim, J.L., Wohl, E., Collins, B.D., 2014. Feedbacks in human-landscape systems. Environ. Manage. 53, 28–41.

Ellis, E.C., 2004. Long-term ecological changes in the densely populated rural landscapes of China. In: DeFries, R.S., Asner, G.P., Houghton, R.A. (Eds.), Ecosystems and Land Use Change. American Geophysical Union, Washington, DC, pp. 303–320. Ellis, E.C., Wang, H., Xiao, H., Peng, K., Liu, X.P., Li, S.C., Ouyang, H., Cheng, X., Yang, L.Z., 2006. Measuring long-term ecological changes in densely populated landscapes using current and historical high resolution imagery. Remote Sens. Environ. 100, 457–473. Ellis, E.C., 2011. Anthropogenic transformation of the terrestrial biosphere. Philos. Trans. R. Soc. A 369, 1010–1035. Foley, J.A., DeFries, R., Asner, G.P., Barford, C., Bonan, G., Carpenter, S.R., 2005. Global consequences of land use. Science 309, 570–574. Garbarino, M., Lingua, E., Marzano, R., Urbinati, C., Bhuju, D., Carrer, M., 2014. Human interactions with forest landscape in the Khumbu valley. Nepal Anthropocene 6, 39–47. Guns, M., Vanacker, V., 2014. Shifts in landslide frequency-area distribution after forest conversion in the tropical Andes. Anthropocene 6, 60–70. Liu, J., Dietz, T., Carpenter, S.R., Alberti, M., Folke, C., Moran, E., Pell, A.N., Deadman, P., Kratz, T., Lubchenco, J., Ostrom, E., Ouyang, Z., Provencher, W., Redman, C.L., Schneider, S.H., Taylor, W.W., 2007. Complexity of coupled human and natural systems. Science 317, 1513–1516. Macklin, M.G., Lewin, J., Jones, A.F., 2014. Anthropogenic alluvium: an evidencebased meta-analysis for the UK Holocene. Anthropocene 6, 26–38. Madricardo, F., Donnici, S., 2014. Mapping past and recent landscape modifications in the Lagoon of Venice through geophysical surveys and historical maps. Anthropocene 6, 71–81. Sofia, G., Prosdocimi, M., Dalla Fontana, G., Tarolli, P., 2014. Evidences and effects of changes in the artificial drainage network during the past half-century: a case study in the Veneto floodplain (Italy). Anthropocene 6, e1–e15. Tarolli, P., 2014. High-resolution topography for understanding Earth surface processes: opportunities and challenges. Geomorphology 216, 295–312. Tarolli, P., Preti, F., Romano, N., 2014. Terraced landscapes: From an old best practice to a potential hazard for soil degradation due to land abandonment. Anthropocene 6, 10–25. Valese, E., Conedera, M., Held, A.C., Ascoli, D., 2014. Fire, humans and landscape in the European Alpine region during the Holocene. Anthropocene 6, 48–59. Vanacker, V., Bellin, N., Molina, A., Kubik, P.W., 2014. Erosion regulation as a function of human disturbances to vegetation cover: a conceptual model. Landsc. Ecol. 29, 293–309. Zalasiewicz, J., Waters, C.N., Williams, M., 2014. Human bioturbation, and the subterranean landscape of the Anthropocene. Anthropocene 6, 3–9.

Paolo Tarollia Veerle Vanackerb Hans Middelkoopc Antony G. Brownd a University of Padova, Department of Land and Agroforest Environments, Agripolis, viale dell’Universita` 16, 35020 Legnaro (PD), Italy b Universite´ catholique de Louvain, Earth and Life Institute, Georges Lemaıˆtre Centre for Earth and Climate Research, Place Louis Pasteur 3 boıˆte L4.03.08, 1348 Louvain-la-Neuve, Belgium c Utrecht University, Department of Physical Geography, 3508 TC Utrecht, Netherlands d University of Southampton, Palaeoenvironmental Laboratory, Southampton SO17 1BJ, United Kingdom