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This issue of WeltTrends features the debate about the future of the transatlantic relationship and world order after the Iraq war. It was started by Thomas Risse with his article in the previous edition. Thomas Risse elaborated on three main points of contention between the United States and Europe: the role of international law and multilateralism, democracy and human rights, and the strategy towards new security threats. Most of the scholars, contributing to the debate in this issue agree with Risse in that there is no alternative to the transatlantic partnership and offer possible paths towards its renewal. The debate will be continued with additional comments and a rebuttal by Thomas Risse in the next Winter issue.
Carbon (C) sequestration in soils plays a key role in the global C cycle. It is therefore crucial to adequately monitor dynamics in soil organic carbon (Delta SOC) stocks when aiming to reveal underlying processes and potential drivers. However, small-scale spatial (10-30 m) and temporal changes in SOC stocks, particularly pronounced in arable lands, are hard to assess. The main reasons for this are limitations of the well-established methods. On the one hand, repeated soil inventories, often used in long-term field trials, reveal spatial patterns and trends in Delta SOC but require a longer observation period and a sufficient number of repetitions. On the other hand, eddy covariance measurements of C fluxes towards a complete C budget of the soil-plant-atmosphere system may help to obtain temporal Delta SOC patterns but lack small-scale spatial resolution.
To overcome these limitations, this study presents a reliable method to detect both short-term temporal dynamics as well as small-scale spatial differences of Delta SOC using measurements of the net ecosystem carbon balance (NECB) as a proxy. To estimate the NECB, a combination of automatic chamber (AC) measurements of CO2 exchange and empirically modeled aboveground biomass development (NPPshoot / were used. To verify our method, results were compared with Delta SOC observed by soil resampling.
Soil resampling and AC measurements were performed from 2010 to 2014 at a colluvial depression located in the hummocky ground moraine landscape of northeastern Germany. The measurement site is characterized by a variable groundwater level (GWL) and pronounced small-scale spatial heterogeneity regarding SOC and nitrogen (Nt) stocks. Tendencies and magnitude of Delta SOC values derived by AC measurements and repeated soil inventories corresponded well. The period of maximum plant growth was identified as being most important for the development of spatial differences in annual Delta SOC. Hence, we were able to confirm that AC-based C budgets are able to reveal small-scale spatial differences and short-term temporal dynamics of Delta SOC.
The United States, despite impressive efforts, have not reduced Colombian drug supplies over the recent years. Policy ineffectiveness results from problems in Colombia, including poverty, strong non-state actors, as well as a weak state and society. On the US side, ineffectiveness results from a geographically selective approach, a reliance on coercion, and bilateralism. The US has exacerbated human rights violations, environmental destruction, the displacement of the drug industry within Colombia, and the spread of Colombian problems to neighbouring countries.