Afforestation of European landscapes: How do different farmer types respond to EU agri-environmental schemes?

This paper investigates how different types of farmers manage the landscape with primary emphasis on farmland afforestation, planned landscape changes, and the extent to which EU agri-environmental schemes take farm type specific characteristics into account in information strategies. The empirical data concern landscape practices of more than 2,000 landowners in 16 European areas in eight countries who were surveyed using quantitative questionnaires. Supplementary in-depth interviews were conducted for two case areas in Denmark to further investigate the role of the policy information environment. The analysis is based on a categorization of the farmers into hobby, part-time, full-time and retired farmers. This study shows that hobby farmers constitute a high proportion of landowners and manage a large part of the rural landscape. At the same time, hobby farmers are relatively more interested in landscape changes and differ from other landowners by considering farmland afforestation more often than full-time landowners, for example. Yet, 40% of the hobby farmers who are considering farmland afforestation are not familiar with the agri-environmental scheme for farmland afforestation. One reason may be their low membership rate in traditional information networks such as farmers’ or foresters’ associations, as revealed by the in-depth analysis of the cases in Denmark. Thus, it is proposed that policy impact may be improved if farmer type specific differences are explicitly taken into account in the scheme logistics for EU agri-environmental schemes.     

Tourmaline Reference Materials for the In Situ Analysis of Oxygen and Lithium Isotope Ratio Compositions

Three tourmaline reference materials sourced from the Harvard Mineralogical and Geological Museum (schorl 112566, dravite 108796 and elbaite 98144), which are already widely used for the calibration of in situ boron isotope measurements, are characterised here for their oxygen and lithium isotope compositions. Homogeneity tests by secondary ion mass spectrometry (SIMS) showed that at sub‐nanogram test portion masses, their ¹⁸O/¹⁶O and ⁷Li/⁶Li isotope ratios are constant within ± 0.27‰ and ± 2.2‰ (1s), respectively. The lithium mass fractions of the three materials vary over three orders of magnitude. SIMS homogeneity tests showed variations in ⁷Li/²⁸Si between 8% and 14% (1s), which provides a measure of the heterogeneity of the Li contents in these three materials. Here, we provide recommended values for δ¹⁸O, Δ’¹⁷O and δ⁷Li for the three Harvard tourmaline reference materials based on results from bulk mineral analyses from multiple, independent laboratories using laser‐ and stepwise fluorination gas mass spectrometry (for O), and solution multi‐collector inductively coupled plasma‐mass spectroscopy (for Li). These bulk data also allow us to assess the degree of inter‐laboratory bias that might be present in such data sets. This work also re‐evaluates the major element chemical composition of the materials by electron probe microanalysis and investigates these presence of a chemical matrix effect on SIMS instrumental mass fractionation with regard to δ¹⁸O determinations, which was found to be < 1.6‰ between these three materials. The final table presented here provides a summary of the isotope ratio values that we have determined for these three materials. Depending on their starting mass, either 128 or 512 splits have been produced of each material, assuring their availability for many years into the future.     

Identification of extreme storm surges with high-impact potential along the German North Sea coastline

Planning and design of coastal protection rely on information about the probabilities of very severe storm tides and the possible changes that may occur in the course of climate change. So far, this information is mostly provided in the form of high percentiles obtained from frequency distributions or return values. More detailed information and assessments of events that may cause extreme damages or have extreme consequences at the coast are so far still unavailable. We describe and compare two different approaches that may be used to identify highly unlikely but still physically possible and plausible events from model simulations. Firstly, in the case when consistent wind and tide-surge data are available, different metrics such as the height of the storm surge can be derived directly from the simulated water levels. Secondly, in cases where only atmospheric data are available, the so called effective wind may be used. The latter is the projection of the horizontal wind vector on that direction which is most effective in producing surges at the coast. Comparison of events identified by both methods show that they can identify extreme events but that knowledge of the effective wind alone does not provide sufficient information to identify the highest storm surges. Tracks of the low-pressure systems over the North Sea need to be investigated to find those cases, where the duration of the high wind is too short to induce extreme storm tides. On the other hand, factors such as external surges or variability in mean sea level may enhance surge heights and are not accounted for in estimates based on effective winds only. Results from the analysis of an extended data set suggest that unprecedented storm surges at the German North Sea coast are possible even without taking effects from rising mean sea level into account. The work presented is part of the ongoing project “Extreme North Sea Storm Surges and Their Consequences” (EXTREMENESS) and represents the first step towards an impact assessment for very severe storm surges which will serve as a basis for development of adaptation options and evaluation criteria.     

Boron Isotopic Composition and Concentration of Ten Geological Reference Materials

We present boron isotope and concentration data from magmatic (komatiitic to rhyolitic) and sedimentary geological silicate and artificial glass reference materials that cover a wide spectrum of boron isotope compositions and boron concentrations. Boron isotope compositions were determined by TIMS (Cs₂BO₂⁺ -graphite and BO₂^- method) and boron concentrations by ICP-AES. Boron concentrations ranged from 7 to 159μ g^-1 and agree within 14% with published values. Based on replicate analyses of individually prepared sample aliquots an overall external reproducibility of better than 10% was determined. The obtained δ¹¹B values ranged from -12.6 to +13.6% and were reproducible within 1.1 % (2 RSD; excluding NTIMS) on the basis of individually prepared sample aliquots. The δ¹¹B values of JA-1 (+5.3%), JB-3 (+5.9%) and JR-2 (+2.9%) overlap the published data within analytical uncertainty. For the first time δ¹¹B values for the TB (-12.6%) and the MPI-DING glasses GOR-128-G (+13.6%), GOR-132-G (+7.1 %) and StHs6/80-G (-4.5%) are reported. The δ¹¹B values obtained by the Cs₂BO₂⁺ -graphite and the BO₂^- method as well as the majority of δ¹¹B values obtained using different sample preparation methods agree within analytical uncertainty. Therefore, we conclude that none of these analytical methods introduce any systematic error on the obtained δ¹¹B values.     

Intercalibration of Mg Isotope Delta Scales and Realisation of SI Traceability for Mg Isotope Amount Ratios and Isotope Delta Values

The continuous improvement of analytical procedures using multi‐collector technologies in ICP‐mass spectrometry has led to an increased demand for isotope standards with improved homogeneity and reduced measurement uncertainty. For magnesium, this has led to a variety of available standards with different quality levels ranging from artefact standards to isotope reference materials certified for absolute isotope ratios. This required an intercalibration of all standards and reference materials, which we present in this interlaboratory comparison study. The materials Cambridge1, DSM3, ERM‐AE143, ERM‐AE144, ERM‐AE145, IRMM‐009 and NIST SRM 980 were cross‐calibrated with expanded measurement uncertainties (95% confidence level) of less than 0.030‰ for the δ^25/24Mg values and less than 0.037‰ for the δ^26/24Mg values. Thus, comparability of all magnesium isotope delta (δ) measurements based on these standards and reference materials is established. Further, ERM‐AE143 anchors all magnesium δ‐scales to absolute isotope ratios and therefore establishes SI traceability, here traceability to the SI base unit mole. This applies especially to the DSM3 scale, which is proposed to be maintained. With ERM‐AE144 and ERM‐AE145, which are product and educt of a sublimation–condensation process, for the first time a set of isotope reference materials is available with a published value for the apparent triple isotope fractionation exponent θ_app, the fractionation relationship ln α(^25/24Mg)/ln α(^26/24Mg).     

Cultural barriers to climate change adaptation: A case study from Northern Burkina Faso

Human adaptation to climate change is a heterogeneous process influenced by more than economic and technological development. It is increasingly acknowledged in the adaptation to climate change literature that factors such as class, gender and culture play a large role when adaptation strategies are either chosen or rejected at the local scale. This paper explores adaptation strategies by focusing on livelihood diversification in the face of the most recent of recurrent droughts in the Sahel. It is shown that for Fulbe, one of the two main ethnic groups in the small village in Northern Burkina Faso studied, culture acts as a major barrier to embracing four of the most successful livelihood strategies: labour migration, working for development projects, gardening, and the engagement of women in economic activities.     

Changing local land systems: Implications of a Chinese rubber plantation in Nambak District,Lao PDR

This paper investigates the direct and cascading land system consequences of a Chinese company's land acquisition for rubber cultivation in northern Laos. Transnational land acquisitions are increasingly acknowledged as an important driver of direct land use conversion with implications for local land‐based livelihoods. The paper presents an empirical case study of the village of Na Nhang Neua in Nambak District, Luang Prabang Province, using a mixed methods approach to investigate the positive and negative implications for household agricultural strategies, income generation and food security. Combining the conceptual lenses of land systems and livelihood approaches, this paper demonstrates how the land use system has changed substantially because of the establishment of the rubber plantation by the company, notably in the linkages between livestock rearing, upland shifting cultivation and lowland paddy rice cultivation. The changes go beyond the immediate competition for land caused by the rubber plantation: a penalty scheme introduced by the rubber company for damage to rubber trees caused by browsing animals has led the villagers to abandon livestock rearing, causing a cascade of negative effects on the entire land use system, especially on soil fertility, rice yields and food production.     

Land system changes in the context of urbanisation: Examples from the peri-urban area of Greater Copenhagen

Peri-urban areas are characterised by great heterogeneity and rapid changes of land use. Furthermore, population composition changes as peri-urban areas offer attractive residential alternatives to city centres or more remote locations. The dynamic processes leave peri-urban areas in an in-between situation, neither city nor countryside and home to a range of functions, spanning from agricultural production to residential and recreational areas. The paper investigates the urbanisation of agricultural areas in the Greater Copenhagen region based on quantitative data collected on agricultural properties in nine study areas between 1984 and 2004. The overall conclusion is that agricultural land use has continued largely unaffected by the processes of urbanisation. However, most of the production is concentrated on a few very large full-time farms. In addition, the economic activities have been greatly diversified over the last three decades. The structural components of the areas (land use and landscape elements) thus appear more resilient than the socio-economic system (declining number of full-time farmers and increasing number of owners engaged in other gainful activities). However, at some point this discrepancy will disappear and rapid land use changes may be expected.     

Elemental dispersion and stable isotope fractionation during reactive fluid-flow and fluid immiscibility in the Bufa del Diente aureole,NE-Mexico: evidence from radiographies and Li,B, Sr,Nd, and Pb isotope systematics

The 31.6±0.3 Ma old Bufa del Diente alkali-syenite (NE Mexico) intruded a sequence of Cretaceous limestones with intercalated sub-horizontal chert layers. The cherts acted as aquifers that facilitated transport of brines and pegmatitic melts within the shallow-level (<1 kbar) contact-metamorphic aureole. Fluid-driven reactions between chert and marble wallrock, and the influx of late melts and various fluids gave rise to distinct chemical and isotopic signatures within the aquifer and across the zones of infiltration and fluid-driven reaction. Aqueous brines of magmatic origin produced thick wollastonite mantles around the chert layers. Wollastonite formation occurred at the expense of limestone and chert and generated CO₂. This CO₂-induced fluid unmixing into an aqueous brine and a low-density CO₂-rich fluid, which was lost to the overlying marble where it oxidized organic matter and caused ¹³C and ¹⁸O shifts in a zone some 5–10 cm wide. After wollastonite formation, the chert aquifers were locally intruded by pegmatite veins carrying alkali feldspar, quartz, aegirine-augite, eudialyte, zircon, and apatite. Aqueous fluids that exsolved during crystallization of the pegmatite veins escaped along late cross-fractures and migrated along the inner and outer borders of the wollastonite margins. Chemical dispersion patterns of U, Al, Na + K, P, S, Fe, and REE across the chert-to-marble boundary and its metasomatic rims are shown by autoradiography and neutron-induced radiography. Scavenging of cations at mineralogical contacts and cation transport into the marbles occurred only on the mm to cm scale. Isotopic data for Pb and Sr across a simple metachert-marble boundary and for Pb, Sr, Nd, B, and Li across a metachert-pegmatite-marble sequence demonstrate the following: (1) The Pb and Sr isotopic signature of early fluids was buffered by the carbonate wallrock. Only late fluids, shielded from wallrock interaction by a wollastonite mantle, variably preserved a memory of their initial magmatic signature. (2) Since the Nd isotope signature of marble and chert is bound to calcite and clay minerals, systematic shifts to unradiogenic Nd in marble reflect loss of carbonate-bound Nd as the wollastonite margin is approached. Nd in the wollastonite margin is dominated by Nd originally bound to clay minerals. The later emplacement of the pegmatite, which carried the Nd isotope signature of its alkali-syenite source, had little effect on the Nd isotopic composition of the wollastonite rim. (3) Although the Li and B isotopic compositions reflect the alkali-syenite source, they are also affected by isotopic fractionation and partitioning between melt, fluid, and solids.Editorial responsibility J. Hoefs     

Historical footprints in contemporary land use systems: forest cover changes in savannah woodlands in the Sudano-Sahelian zone

The paper analyses land use trajectories in savannah woodlands in the Central-West Region, Burkina Faso and the Upper East Region in northern Ghana by use of satellite images and historical archives. Observed trends differ in terms of spatial location and correlation with population pressure from normally accepted characterizations. Colonial forestry policies are proposed as key determinants of present-day land use patterns. However, these reinforced pre-colonial land use patterns inasmuch as land gazetted as forest reserves were tracts affected by vectors of human and livestock disease. It is suggested that the transformation of wooded agricultural landscapes in the Sudano-Sahelian region is the outcome of historically and culturally embedded interactions between complex social, economic and ecological processes which operate at widely varying scales and which change over time; the implications hereof for modelling of global environmental issues is discussed.