No abstract

With a new ‘technosphere’ concept, Peter Haff offers a provocative reconceptualization of technology in Anthropocene, not as derivative consequence of human activity, but as a new ‘quasi-autonomous’ sphere of the environment that conditions human survival within the Earth System. Paying attention to the expansion of the orbital satellites in outer space, this paper suggests that technosphere analysis needs to conceptualize specific histories of the planetary-scale technology while considering how these technologies provide the epistemological basis and limitations for the technosphere. Satellites enhance the capacity of the technosphere as a system and provide systemic knowledge that is the basis for the meaning of the technosphere concept. Yet, this expansion is rooted in the contingencies of earthly geopolitics and the continual breakdown of technology – in this instance as a space debris layer formed in orbit around Earth that endangers the technosphere itself.

The abundance and properties of small standing water bodies (SSWB) is globally not well known for their ecological importance is undervalued and their detection suffers from technical limitations. In the current study, we used a combination of GIS-based methods (satellite, orthophoto, ground validation) to evaluate regional estimates of standing water body (SWB) inventories in two geographically different parts of Europe – France, and Estonia. In our study the SWBs surface area threshold limit was 0.00001 km2, exceeding the limits of previous studies (>0.002 km2). The total number of SWBs in Estonia is 111 552 (2.5 per km2) and in France 598 371 (1.1 per km2). Our estimates show that the median size of SWBs in Estonia and France is 0.0003 km2 and 0.0007 km2 respectively, meaning that most of the SSWBs are not included in the global inventories, and their number is therefore underestimated. SSWBs (area below 0.01 km2) form a significant share of the total shoreline length of SWBs, 70.3% in Estonia and 58.8% in France. As nearshore areas are often very productive with diverse habitats, the SSWBs hold a crucial role in maintaining biodiversity. Our results provide quantitative evidence that SSWBs are vital and abundant landscape elements, freshwater resources, and habitats that should not be ignored in global inventories.

In order to assess the geochemical and stable isotopic response of recent sediments to the changing anthropogenic influence on Lake Nõmmejärv, bulk geochemistry determined by XRF spectroscopy and carbon and oxygen stable isotopes in carbonates (δ 13 C carb and δ 18 O carb ) were analysed. A time scale was defined by the 210 Pb dating method. The most significant change in sediment composition was a steep transition from organic to mineral rich sediment at the beginning of the 1970s. Our data confirm that this shift was caused by an abrupt influx of allochthonous mineral matter (Si, Al, K, Rb, Ti, Zr) derived from mine waters that started to be drained from an oil shale mine into the lake through an artificial channel. Since then, the minerogenic sedimentation remains high but after the initial peak, the proportion of siliciclastic matter decreases in favour of CaCO 3 accumulation. During the last 40 years the carbonate content increased from 7% to 40%. Geochemical evidence supports the assumption that the key mechanism in the formation of carbonates was biologically mediated authigenic CaCO 3 precipitation. In addition, decrease in sediment organic matter due to high minerogenic sedimentation forms more favourable conditions for the preservation of the accumulated CaCO 3 . The shift in the δ 13 C carb values during the 1970s and 1980s indicates potential links between CaCO 3 precipitation and the increase in lake productivity.

Palaeolimnological techniques were utilized to determine the extent of the effect of anthropogenic pollutants or other environmental stressors on three lake ecosystems over the last 200 years. The ecology of the study sites has experienced significant changes due to various activities such as (1) extensive catchment drainage and using poisoning as a fish management measure, (2) seepage of urban waste water due to establishment and growth of a town and (3) artificial inflow of oil-shale mining waters. Sediment geochemical composition, fossil pigments and Cladocera remains from the sediment cores were analysed to demonstrate that sufficient information can be derived from sediments to permit a historical reconstruction. The integrated use of archival maps, historical records and lake monitoring data confirmed links to anthropogenic pollutants, primarily on the catchment level. The examples show how the sediment indicators provide unique insights into the causes and temporal dynamics of lake ecosystem changes relevant for environmental management decisions. This study demonstrates that palaeolimnology has great potential to assist in eutrophication assessment and management efforts in waterbodies.