A Multilevel Analysis of Agricultural Trade and Socioeconomic Inequality in Rural Mozambique

This study uses a mixed methodology to investigate the relationship between agricultural trade and socioeconomic inequality in Mozambique at multiple geographical scales. The quantitative analysis examines all rural regions of the country and a nationally representative sample of rural households, whereas the qualitative analysis focuses primarily on two case study villages. Research findings suggest that social and geographical context greatly influence the relationships between agricultural trade and regional inequality. Trade-related effects on economic inequality—and the social status of traders—vary across Mozambican regions. Results suggest that trade increases inequality in regions where traders have low social status, but reduces inequality in areas where they have high social status. These findings suggest that social and economic factors work together to shape landscapes of inequality.     

Simulation Study of a Robust Algorithm for Soil Moisture and Surface Roughness Estimation Using L‐Band Radar Backscatter

Abstract

Various inversion algorithms have been developed to obtain estimates of soil moisture and surface roughness parameters from multifrequency, multiangle, and multipolarization radar reflectances. Since the penetration depth for radar signals increases with wavelength, an inversion algorithm using widely separated frequencies does not yield comparable probing depths. Furthermore, existing algorithms assume a linear relationship between the radar backscatter coefficient (in dB) and soil parameters, such as the volumetric soil moisture, soil surface roughness and surface slope. This assumption is valid only over a narrow range of soil parameters, thereby restricting its operational use under realistic conditions. Our research specifically explored the use of inversion algorithms based on L‐Band radar reflectances at 1 GHz and 2 GHz frequencies in order to retain relatively consistent probing depths. In order to extend the range of applicability, a non‐linear exponential‐type relationship was developed between radar reflectance at a specified frequency, polarization and incidence angle combination, and soil parameters of interest, viz., soil moisture, surface roughness, and surface slope. An over‐constrained inversion algorithm using a six‐parameter combination was found to yield relatively accurate estimates of soil parameters over a wide range of soil conditions even in the presence of system error.     

Type C Ca, Al-rich inclusions from Allende: Evidence for multistage formation

The coarse-grained, igneous, anorthite-rich (Type C) CAIs from Allende studied (100, 160, 6-1-72, 3529-40, CG5, ABC, TS26, and 93) have diverse textures and mineralogies, suggesting complex nebular and asteroidal formation histories. CAIs 100, 160, 6-1-72, and 3529-40 consist of Al,Ti-diopside (fassaite; 13-23 wt% Al₂O₃, 2-14 wt% TiO₂), Na-bearing åkermanitic melilite (0.1-0.4 wt% Na₂O; Åk_30-75), spinel, and fine-grained (∼5-10 μm) anorthite groundmass. Most of the fassaite and melilite grains have “lacy” textures characterized by the presence of abundant rounded and prismatic inclusions of anorthite ∼5-10 μm in size. Lacy melilite is pseudomorphed to varying degrees by grossular, monticellite, and pure forsterite or wollastonite. CAI 6-1-72 contains a relict Type B CAI-like portion composed of polycrystalline gehlenitic melilite (Åk_10-40), fassaite, spinel, perovskite, and platinum-group element nuggets; the Type B-like material is overgrown by lacy melilite and fassaite. Some melilite and fassaite grains in CAIs 100 and 160 are texturally similar to those in the Type B portion of 6-1-72. CAIs ABC and TS26 contain relict chondrule fragments composed of forsteritic olivine and low-Ca pyroxene; CAI 93 is overgrown by a coarse-grained igneous rim of pigeonite, augite, and anorthitic plagioclase. These three CAIs contain very sodium-rich åkermanitic melilite (0.4-0.6 wt% Na₂O; Åk_63-74) and Cr-bearing Al,Ti-diopside (up to 1.6 wt% Cr₂O₃, 1-23 wt% Al₂O, 0.5-7 wt% TiO₂). Melilite and anorthite in the Allende Type C CAI peripheries are replaced by nepheline and sodalite, which are crosscut by andradite-bearing veins; spinel is enriched in FeO. The CAI fragment CG5 is texturally and mineralogically distinct from other Allende Type Cs. It is anorthite-poor and very rich in spinel poikilitically enclosed by Na-free gehlenitic melilite (Åk_20-30), fassaite, and anorthite; neither melilite nor pyroxene have lacy textures; secondary minerals are absent. The Al-rich chondrules 3655b-2 and 3510-7 contain aluminum-rich and ferromagnesian portions. The Al-rich portions consist of anorthitic plagioclase, Al-rich low-Ca pyroxene, and Cr-bearing spinel; the ferromagnesium portions consist of fosteritic olivine, low-Ca pyroxene, and opaque nodules.We conclude that Type C CAIs 100, 160, 6-1-72, and 3529-40 formed by melting of coarse-grained Type B-like CAIs which experienced either extensive replacement of melilite and spinel mainly by anorthite and diopside (traces of secondary Na-bearing minerals, e.g., nepheline or sodalite, might have formed as well), or addition of silica and sodium during the melting event. CG5 could have formed by melting of fine-grained spinel-melilite CAI with melilite and spinel partially replaced anorthite and diopside. CAIs ABC, 93, and TS-26 experienced melting in the chondrule-forming regions with addition of chondrule-like material, such as forsteritic olivine, low-Ca pyroxene, and high-Ca pyroxene. Anorthite-rich chondrules formed by melting of the Al-rich (Type C CAI-like) precursors mixed with ferromagnesian, Type I chondrule-like precursors. The Allende Type C CAIs and Al-rich chondrules experienced fluid-assisted thermal metamorphism, which resulted in pseudomorphic replacement of melilite and anorthite by grossular, monticellite, and forsterite (100, 160, 6-1-72, 3592-40) or by grossular, monticellite, and wollastonite (ABC, 93, TS-26). The pseudomorphic replacement was followed or accompanied by iron-alkali metasomatic alteration resulting in replacement of melilite and anorthite by nepheline and sodalite, enrichment of spinel in FeO, and precipitation of salite-hedenbergite pyroxenes, wollastonite, and andradite in fractures and pores in and around CAIs.     

Is Ocean Acidification an Open-Ocean Syndrome? Understanding Anthropogenic Impacts on Seawater pH

Ocean acidification due to anthropogenic CO₂ emissions is a dominant driver of long-term changes in pH in the open ocean, raising concern for the future of calcifying organisms, many of which are present in coastal habitats. However, changes in pH in coastal ecosystems result from a multitude of drivers, including impacts from watershed processes, nutrient inputs, and changes in ecosystem structure and metabolism. Interaction between ocean acidification due to anthropogenic CO₂ emissions and the dynamic regional to local drivers of coastal ecosystems have resulted in complex regulation of pH in coastal waters. Changes in the watershed can, for example, lead to changes in alkalinity and CO₂ fluxes that, together with metabolic processes and oceanic dynamics, yield high-magnitude decadal changes of up to 0.5 units in coastal pH. Metabolism results in strong diel to seasonal fluctuations in pH, with characteristic ranges of 0.3 pH units, with metabolically intense habitats exceeding this range on a daily basis. The intense variability and multiple, complex controls on pH implies that the concept of ocean acidification due to anthropogenic CO₂ emissions cannot be transposed to coastal ecosystems directly. Furthermore, in coastal ecosystems, the detection of trends towards acidification is not trivial and the attribution of these changes to anthropogenic CO₂ emissions is even more problematic. Coastal ecosystems may show acidification or basification, depending on the balance between the invasion of coastal waters by anthropogenic CO₂, watershed export of alkalinity, organic matter and CO₂, and changes in the balance between primary production, respiration and calcification rates in response to changes in nutrient inputs and losses of ecosystem components. Hence, we contend that ocean acidification from anthropogenic CO₂ is largely an open-ocean syndrome and that a concept of anthropogenic impacts on marine pH, which is applicable across the entire ocean, from coastal to open-ocean environments, provides a superior framework to consider the multiple components of the anthropogenic perturbation of marine pH trajectories. The concept of anthropogenic impacts on seawater pH acknowledges that a regional focus is necessary to predict future trajectories in the pH of coastal waters and points at opportunities to manage these trajectories locally to conserve coastal organisms vulnerable to ocean acidification.     

Thinking inside the neoliberal box: The micro-politics of agro-food philanthropy

This paper examines a philanthropy-led initiative which has as its objective to jump start the transition to a more sustainable and just food system in California. The first major project funded was a “vivid picture” of California’s food system twenty-five years in the future. The outcome of the project is a report that is glossed with the tropes of neoliberalism in all of its key organizing frameworks, analytics, cognitive maps, and idioms and argues for “opportunities-based approaches” as the engine of change. Yet, as described in the paper, this outcome was initially under-determined, and, in fact, the funders had originally intended to leverage their resources for large scale transformation. By examining four moments in the development of the Vivid Picture project, the grantee selection, the modeling exercise, the stakeholder meetings, and the qualitative interviews, this paper will show how existing techniques of neoliberal governance such as modeling, audit, best-practices, and stakeholder participation, as well as current norms of philanthropy, shaped what is thinkable and hence actable. It will also show how “stakeholders” played a constitutive role in producing the outcomes of the project, in part because their input reflected already-developed notions of the possible within the current climate of neoliberalism. In the end it will argue that the failure of the Vivid Picture to look beyond the neoliberal present is itself evidence of the proliferation of neoliberal governmentalities. Still, the entire process galvanized many of the movement actors who were left out of the funding process and, in that way, produced political openings.     

Electron Microprobe/SIMS Determinations of Al in Olivine: Applications to Solar Wind,Pallasites and Trace Element Measurements

Electron probe microanalyser measurements of trace elements with high accuracy are challenging. Accurate Al measurements in olivine are required to calibrate SIMS implant reference materials for measurement of Al in the solar wind. We adopt a combined EPMA/SIMS approach that is useful for producing SIMS reference materials as well as for EPMA at the ~ 100 µg g^?1 level. Even for mounts not polished with alumina photoelectron spectroscopy shows high levels of Al surface contamination. In order to minimise electron beam current density, a rastered 50 × 100 µm electron beam was adequate and minimised sensitivity to small Al‐rich contaminants. Reproducible analyses of eleven SIMS‐cleaned spots on San Carlos olivine agreed at 69.3 ± 1.0 µg g^?1. The known Al mass fraction was used to calibrate an Al implant into San Carlos. Accurate measurements of Al were made for olivines in the pallasites: Imilac, Eagle Station and Springwater. Our focus was on Al in olivine, but our technique could be refined to give accurate electron probe measurements for other contamination‐sensitive trace elements. For solar wind, it is projected that the Al/Mg abundance ratio can be determined to 6%, a factor of 2 more precise than the solar spectroscopic ratio.     

Re-analysis of late Quaternary dust mass accumulation rates in Serbia using new luminescence chronology for loess–palaeosol sequence at Surduk

Despite numerous palaeoenvironmental investigations of loess–palaeosol sequences across the Carpathian Basin, well-dated high-resolution records are scarce. This paper presents a new high-resolution chronology for the loess-palaeosol sequence at Surduk (Serbia), based on optically stimulated luminescence (quartz) and post-infrared infrared stimulated luminescence (polymineral) dating. The presented record spans 53–19 ka, with primary loess deposition occurring after 52±2 ka, and differs from previously published chronologies that relied on less precise and now superseded dating protocols. Based on the new chronology, mass accumulation rates (MARs) for Surduk were constructed and compared with sites in the Carpathian Basin. The results demonstrate that accumulation periods across this area are not consistent in timing or rates. The high-resolution dating strategy identifies a disturbance in sediment deposition that occurred after 45±2 ka and implies that site contains a hiatus. Finally, we show samples that failed routine dose recovery and preheat plateau tests, and had low fast ratios. Supported by bulk sample geochemical analysis it is proposed that a potential abrupt source shift, during the Last Glacial Maximum, may be the cause of the anomalous luminescence behaviour.     

Determination of Precise and Accurate 51V/50V Isotope Ratios by MC‐ICP‐MS,Part 1: Chemical Separation of Vanadium and Mass Spectrometric Protocols

We present the first technique to obtain precise and accurate vanadium (V) stable isotope compositions by chemical isolation and multi‐collector inductively coupled plasma‐mass spectrometry (MC‐ICP‐MS). Separation of V from matrix elements was achieved via five separate ion exchange columns. The procedure quantitatively removed Ti and Cr, which contain direct isobaric interferences on the minor isotope ⁵⁰V. Isotope compositions were determined using a conventional standard solution‐sample bracketing technique. The V isotope composition for an in‐house secondary standard solution from BDH Chemicals was δ⁵¹V = ?1.19 ± 0.12‰ (2s, n = 600), measured as the per mil deviation relative to the composition of a widely available Specpure Alfa Aesar (AA) vanadium solution. This represents an improvement in measurement precision on previous techniques of almost two orders of magnitude. The effects of adding Cr, Ti and S to standard solutions were explored to determine the robustness of protocols. Only very low levels of these elements could be tolerated to obtain precise and accurate isotope compositions and was achieved with the chemical purification procedure. Standard solutions from AA and BDH processed as unknowns through the entire chemical separation and measurement protocols returned 100% yields and the same isotopic compositions as those of unprocessed standard solutions.     

Assessment of USGS BCR-2 as a Reference Material for Silicate Rock U-Pa Disequilibrium Measurements

The accuracy of ²³¹Pa-²³⁵U measurements can be readily assessed using a secular equilibrium reference material (RM), but a secular equilibrium RM is also required to calibrate the ²³³Pa spike used in ²³¹Pa determinations. The only silicate RM commonly accepted to be in secular equilibrium is Table Mountain Latite (TML) and so an additional reference is required. Our measurements on the widely available USGS BCR-2 (Basalt Columbia River) rock powder yielded (²³¹Pa/²³⁵U) = 0.997 ± 0.013 2s (n = 10), indicating its value as a secondary reference to test the fidelity of U-Pa determinations. Such a reference material additionally provides a useful check on data reduction, which our literature survey highlights can lead to discrepancies of up to 53% between reported (²³¹Pa/²³⁵U) activity ratios and corresponding U and Pa concentration data.     

Circulation on the West Antarctic Peninsula derived from 6 years of shipboard ADCP transects

Over the past 30 years, shelf circulation on the West Antarctic Peninsula (WAP) has been derived from hydrographic data with a reasonable level of confidence. However, with the exception of a very few drifter tracks and current-meter timeseries from moorings, direct velocity measurements have not previously been available. In this article, shelf and shelf-edge circulation is examined using a new velocity dataset, consisting of several years of acoustic Doppler current profiler transects, routinely collected along the ship tracks of the R/V Gould and the R/V Palmer since the fall of 1997. Initial processing and quality control is performed by Dr. Teresa Chereskin and Dr. Eric Firing, who then place the data in an archive accessible by public website, resulting in the broad availability of the data for a variety of uses. In this study, gridded Eulerian means have been calculated to examine circulation on the shelf and slope off the South Shetland Islands, in Bransfield Strait, and on the shelf and slope south of these regions, including Marguerite Bay and the adjacent shelf and shelf-edge. Shelf-edge flow is northeastward in the study area from the offshore of northern Alexander Island to Smith Island, while a southward flowing shelf-edge feature, probably the shallow component of the polar slope current, appears between Elephant Island and Livingston Island. The shallow polar slope current appears to turn shoreward to pass through Boyd Strait between Smith and Livingston Islands. In Bransfield Strait, there is cyclonic circulation. The previously identified northeastward-flowing South Shetland Island jet is strong and present in all seasons, with a large barotropic component not revealed by the hydrography-based velocities derived in the past. On the shelf seaward of Adelaide, Anvers and Brabant Islands, the strong along-shelf Antarctic Peninsula coastal current flows southwestward, with strongest velocities in winter (June–September) off Anvers and Brabant Islands, but stronger in summer (December–March) off Adelaide Island. Seaward of Marguerite Bay, there is seaward flow in the upper 400 m of the water column over the southwest bank of Marguerite Trough, strongest in summer, and shoreward flow near the northeast bank and adjacent shallower shelf areas.