Reflexive governance: exploring the concept and assessing its critical potential for sustainable development. Introduction to the special issue

ABSTRACT

Elaborated in publications on transition management, sustainability governance and deliberative environmental governance, ‘reflexive governance’ addresses concerns about social-ecological vulnerabilities, flawed conceptualisations of human-nature relations fragmented governance regimes and conditions for a sustainability transition. Key barriers to reflexive government include unavoidable politics; the influence of broader discursive systems that shape actors’ strategic interests; and structural and deliberate limitations to the range of admitted epistemological understandings, normative perspectives and material practices. Against this background, the contributions to the special issue provide novel conceptual linkages between reflexive governance and boundary objects, intercultural dialogue, conflict management heuristics, discourse linguistics, theories of the policy cycle and reflexive law, network and learning theories, and Lasswell’s ‘developmental constructs’. Based on the contributions, we identify five inherent conceptual tensions of reflexive governance: between the openness of horizontal learning processes and the desired direction towards sustainable development; between reflexive governance as a normative or procedural concept; between expected learning orientations and other, strategic orientations; between governance as a precondition for reflexivity and reflexive learning as a precondition for reorganized governance structures; and between reflexivity as an open-ended, evolutionary process and the need to strategically defend the space for reflexivity against powerful groups with an interest in the status quo.     

Fine roots in stands of Fagus sylvatica and Picea abies along a gradient of soil acidification

Root length of naturally grown young beech trees (Fagus sylvatica L.) was investigated in 26 forest plots of differing base saturation and nitrogen deposition. The relative length of finest roots (<0.25 mm) was found to decrease in soils with low base saturation. A similar reduction of finest roots in plots with high nitrogen deposition was masked by the effect of base saturation. The formation of adventitious roots was enhanced in acidic soils. The analysis of 128 soil profiles for fine roots of all species present in stands of either Fagus sylvatica L., Picea abies [Karst.] L. or both showed a decreased rooting depth in soils with < or =20% base saturation and in hydromorphic soils. For base rich, well drained soils an average rooting depth of 108 cm was found. This decreased by 28 cm on acidic, well drained soils. The results suggest an effect of the current soil acidification in Switzerland and possibly also of nitrogen deposition on the fine root systems of forest trees.     

Impact of soil water regime on degradation and plant uptake behaviour of the herbicide isoproturon in different soil types

The environmental fate of the worldwide used herbicide isoproturon was studied in four different, undisturbed lysimeters in the temperate zone of Middle Europe. To exclude climatic effects due to location, soils were collected at different regions in southern Germany and analyzed at a lysimeter station under identical environmental conditions. ¹⁴C-isoproturon mineralization varied between 2.59% and 57.95% in the different soils. Barley plants grown on these lysimeters accumulated ¹⁴C-pesticide residues from soil in partially high amounts and emitted ¹⁴CO₂ in an extent between 2.01% and 13.65% of the applied ¹⁴C-pesticide. Plant uptake and ¹⁴CO₂ emissions from plants were inversely linked to the mineralization of the pesticide in the various soils: High isoproturon mineralization in soil resulted in low plant uptake whereas low isoproturon mineralization in soil resulted in high uptake of isoproturon residues in crop plants and high ¹⁴CO₂ emission from plant surfaces. The soil water regime was identified as an essential factor that regulates degradation and plant uptake of isoproturon whereby the intensity of the impact of this factor is strongly dependent on the soil type.     

Climate change adaptation and mitigation in smallholder crop–livestock systems in sub-Saharan Africa: a call for integrated impact assessments

African mixed crop–livestock systems are vulnerable to climate change and need to adapt in order to improve productivity and sustain people’s livelihoods. These smallholder systems are characterized by high greenhouse gas emission rates, but could play a role in their mitigation. Although the impact of climate change is projected to be large, many uncertainties persist, in particular with respect to impacts on livestock and grazing components, whole-farm dynamics and heterogeneous farm populations. We summarize the current understanding on impacts and vulnerability and highlight key knowledge gaps for the separate system components and the mixed farming systems as a whole. Numerous adaptation and mitigation options exist for crop–livestock systems. We provide an overview by distinguishing risk management, diversification and sustainable intensification strategies, and by focusing on the contribution to the three pillars of climate-smart agriculture. Despite the potential solutions, smallholders face major constraints at various scales, including small farm sizes, the lack of response to the proposed measures and the multi-functionality of the livestock herd. Major institutional barriers include poor access to markets and relevant knowledge, land tenure insecurity and the common property status of most grazing resources. These limit the adoption potential and hence the potential impact on resilience and mitigation. In order to effectively inform decision-making, we therefore call for integrated, system-oriented impact assessments and a realistic consideration of the adoption constraints in smallholder systems. Building on agricultural system model development, integrated impact assessments and scenario analyses can inform the co-design and implementation of adaptation and mitigation strategies.F     

Transport of a decay chain in homogenous porous media: analytical solutions

With the aid of integral transforms, analytical solutions for the transport of a decay chain in homogenous porous media are derived. Unidirectional steady-state flow and radial steady-state flow in single and multiple porosity media are considered. At least in Laplace domain, all solutions can be written in closed analytical formulae. Partly, the solutions can also be inverted analytically. If not, analytical calculation of the steady-state concentration distributions, evaluation of temporal moments and numerical inversion are still possible. Formulae for several simple boundary conditions are given and visualized in this paper. The derived novel solutions are widely applicable and are very useful for the validation of numerical transport codes.     

Seasonal dynamics of freshwater pathogens as measured by microarray at Lake Sapanca,a drinking water source in the north-eastern part of Turkey

Monitoring drinking water quality is an important public health issue. Two objectives from the 4 years, six nations, EU Project μAqua were to develop hierarchically specific probes to detect and quantify pathogens in drinking water using a PCR-free microarray platform and to design a standardised water sampling program from different sources in Europe to obtain sufficient material for downstream analysis. Our phylochip contains barcodes (probes) that specifically identify freshwater pathogens that are human health risks in a taxonomic hierarchical fashion such that if species is present, the entire taxonomic hierarchy (genus, family, order, phylum, kingdom) leading to it must also be present, which avoids false positives. Molecular tools are more rapid, accurate and reliable than traditional methods, which means faster mitigation strategies with less harm to humans and the community. We present microarray results for the presence of freshwater pathogens from a Turkish lake used drinking water and inferred cyanobacterial cell equivalents from samples concentrated from 40 into 1 L in 45 min using hollow fibre filters. In two companion studies from the same samples, cyanobacterial toxins were analysed using chemical methods and those dates with highest toxin values also had highest cell equivalents as inferred from this microarray study.     

Mineralization and Transfer Processes of <Superscript>14</Superscript>C-labeled Pesticides in Outdoor Lysimeters

A recently designed two-chamber-lysimeter-test-system allows the detailed investigation of degradation, transport and transfer processes of ¹⁴C-labeled substances in soil–plant–atmosphere-systems under outdoor conditions. With this test system it is feasible to distinguish between ¹⁴C-emissions from soil surfaces and ¹⁴C-emissions from plant surfaces in soil monoliths under real environmental conditions. Special soil humidity sensors allow the measurement of soil water content near to the soil surface, in 1 and 5 cm depth. The behavior of organic chemicals can be followed for a whole vegetation period and a mass balance for the applied chemical can be established. Some selected results of the herbicides isoproturon and glyphosate – using the two-chamber-lysimeter-test-system – are presented to demonstrate its applicability for the identification and quantification of the processes that govern pesticide behavior in soil–plant-systems. Mineralization of ¹⁴C-isoproturon was very different in four different soils; the mineralization capacity of the soils ranged from 2 to 60%. Leaching of isoproturon in general was very low, but depending on the soil type and environmental conditions isoproturon and its metabolites could be leached via preferential flow, especially shortly after application. For the herbicide ¹⁴C-glyphosate no accumulation of residues in the soil and no leaching of the residues to deeper soil layers could be observed after three applications. Glyphosate was rapidly degraded to AMPA in the soil. Glyphosate and AMPA were accumulated in soy bean nodules.