Policy conditions for sustainable agriculture in the Netherlands

Summary Sustainability as a goal is widely accepted and ranked high on the political agenda. Although the operationalization of this concept differs, the range of opinions shows a pseudo-consensus. Sustainable agriculture is defined in this paper as an agriculture that fulfils functions with regard to food production, nature and landscape, and the development of the rural areas now and in the future. This requires a set of ecological criteria for the agricultural sector. Besides the ecological aspects, sustainable agriculture has consequences for the economic, cultural and socio-political aspects of society. This paper concentrates on the socio-political conditions for sustainable agriculture. An important strategy for the realisation of sustainable agriculture is the stimulation of sustainable initiatives of (groups of) farmers, in particular on a regional level. The future perspectives of such a bottom-upwards approach are described by giving some examples of initiatives of Dutch farmers. It will be argued that the national governmental policy has to enlarge the scope for the development of farming practices.Dr Ing L.G. (Ina) Horlings studied land and water management at the Larenstein International Agricultural College in Velp before studying geography at the University of Nijmegen. She currently works at this university as a researcher and lecturer in the Department of Environmental Policy Sciences at the University. She is writing her thesis on agricultural policy. Her publications relate to environmental aspects of spatial research, farmer's initiatives and agricultural landuse.     

Humanitarians' ethics: the role of face-to-face experiences in humanitarian aid workers' motivation

This paper analyses the significance of specific ethical experiences for humanitarian aid workers' motivation. Following Emmanuel Levinas's understanding of ethics as arising from intersubjective face-to-face encounters, the study illuminates the experiential origins of the humanitarian commitment by analysing James Orbinski's memoir entitled An Imperfect Offering: Dispatches from the Medical Frontline. Orbinski, a former International Council President at Médecins Sans Frontières, was directly involved in humanitarian responses to several major crises during the 1990s, including those in Somalia, Afghanistan, Rwanda, and what was then Zaire. This paper explores three formative experiences from Orbinski's childhood and teenage years to analyse the personal ethics of humanitarian aid workers and to illuminate the intersection of the personal and professional level of humanitarian aid work. Illustrating that Orbinski's humanitarian commitment is a surrendering to the other's call, the paper argues for stronger inclusion of aid workers' lives and experiences to achieve a comprehensive understanding of humanitarian work.     

Human impact on wild firewood species in the Rural Andes community of Apillapampa, Bolivia

Firewood is the basic fuel source in rural Bolivia. A study was conducted in an Andean village of subsistence farmers to investigate human impact on wild firewood species. A total of 114 different fuel species was inventoried during fieldtrips and transect sampling. Specific data on abundance and growth height of wild firewood species were collected in thirty-six transects of 50 ×2 m². Information on fuel uses of plants was obtained from 13 local Quechua key participants. To appraise the impact of fuel harvest, the extraction impact value (EIV) index was developed. This index takes into account local participants?? appreciation of (1) decreasing plant abundance; (2) regeneration capacity of plants; (3) impact of root harvesting; and (4) quality of firewood. Results suggest that several (sub-)woody plant species are negatively affected by firewood harvesting. We found that anthropogenic pressure, expressed as EIV, covaried with density of firewood species, which could entail higher human pressure on more abundant and/or more accessible species. The apparent negative impact of anthropogenic pressure on populations of wild fuel species is corroborated by our finding that, in addition to altitude, several anthropogenic variables (i.e. site accessibility, cultivation of exotics and burning practices) explain part of the variation in height of firewood species in the surroundings of Apillapampa.     

Linkages in Ghana's gold mining industry: Challenging the enclave thesis

By 2009, Ghana was the second-ranked African producer after South Africa, and had become the world's ninth largest producer of gold, at some 3.8% of global production, up from 2.6% five years earlier. Gold production volumes and revenues rose significantly over the decade from 2000. Yet gold mining tends to be perceived negatively in Ghana, and is seen as providing far less than it should in terms of public revenue, employment, skills development and spillovers, and localised economic development. Gold mining is often depicted as having an enclave status, disconnected and isolated from the rest of the economy. In contrast, the research findings here demonstrate that after a period of strong investment and growth, gold mining can no longer be viewed as an enclave activity: it is in fact more deeply linked into the Ghanaian economy than hitherto understood, through a set of as yet under-researched but promising economic linkages, notably backward linkages, which can potentially be strengthened by policy and support measures.     

A simple bioassay for feeding-stimulants for the young seahare Aplysia juliana

Water extracts of a green alga (Ulva sp.) are known to elicit phagostimulatory responses against a seahare Aplysia sp. In 1984 we happened, however, to find that a seahare shows its feeding preference for filter paper on which an ether extract of Ulva sp. had been absorbed. We succeeded in establishing a simple and reliable bioassay procedure for the feeding-stimulants for the seahare A. juliana, which is applicable to isolation of the active principles.Chemical Studies on Phagostimulants for Marine Gastropods, Part V. For Part IV, see Sakata et al. (1985)     

Aerobic and anaerobic transformations of sulfide in a sewer system--field study and model simulations.

The formation and fate of sulfide in a force main and a downstream-located gravity sewer were investigated in an extensive field study. Sulfide formation in the force main was significant. However, during 14 minutes of transport in the gravity sewer, the sulfide concentration decreased 30%, on average. An application of a conceptual sewer process model for simulating the formation and fate of sulfide was demonstrated. Overall, the model predicted that approximately 90% of the decrease of the sulfide concentration in the gravity sewer was the result of sulfide oxidation and that only a small fraction entered the sewer atmosphere, causing odor and corrosion. Even so, the model predicted concrete corrosion rates of up to 1.2 mm/y in the gravity sewer section.     

Verteilung chemischer Elemente in der Nahrung und Milch stillender Mütter

Goal and Scope

The transfer of various chemical elements from maternal food into human milk was investigated. Transfer factors (hereafter TF) food/mother’s milk were taken to represent those nuclides pertinent to radiation protection in order to estimate possible radioactive burdens of breast-fed babies.

Methods

A total of 23 mothers, mainly from the Euroregion Neisse (PL, CZ, D; all being in their mature phases of lactation), took part in this study (1998–2001), for time periods between two to eight weeks (8805 samples were analyzed). The diurnal uptake of elements was determined by the duplicate method.

Results and Conclusions

TF values determined for Ag, Au, Ba, Cd, Ce, Co, Cr, Cs, Cu, Fe, Ga, I, La, Mn, Mo, Nb, Ni, P, Pb, Ra, Rb, Re, Ru, Sb, Sr, Te, Th, Ti, U_o, Y, Zn, Zr were theoretically analyzed with the following result: metal ions transfer into mother’s milk mainly in coordinated states (i.e. bound to anionic ligands), with TF values which increase according to complex stabilities. Therefore it can be assessed that neither Cd nor Ba, both forming only weak complexes, pose hazards to breastfed children.

Outlook

There are relationships between transfer factors pertaining to certain elements and the amounts of others consumed by the mother; i.e. (changes in) consumption of one element influence the transfer towards women’s milk of another element. Accordingly, strategies can be developed to keep off hazardous substances — including fissiogenic radionuclides — from milk which is far more efficient than traditional isotopic dilution; however, iodide tablets are useful here, too.     

The effect of queen-worker conflict on caste determination in the bumblebee Bombus terrestris

Endocrine analyses were used to investigate the well-known association between queen production and the onset of worker reproduction (termed the competition phase, CPh) in Bombus terrestris. Larvae that reached the age of 5 days before the CPh had a worker-like profile: low juvenile hormone (JH) biosynthesis rates and low JH hemolymph titers. In contrast, larvae that reached the age of 5 days during the CPh had a queen-like profile: high JH biosynthesis rates and high hemolymph JH levels. Larval fate could be manipulated by transplanting egg cells into host colonies with different social structures. There was a steep rise in JH production in larvae transplanted into colonies near or during the CPh. This indicates that during colony development, larvae switch from the ”worker developmental pathway” to the ”queen developmental pathway,” and that the switch is socially regulated. In small rearing groups, larvae reared with queens before the CPh developed into workers, whereas those reared with queens after the CPh developed into queens. Variation in worker type (naive or experienced) did not affect caste determination. Therefore, we hypothesize that queens produce a pheromone that directly inhibits queen differentiation by larvae. We also present two alternative scenarios that explain the timing of gyne production in B. terrestris, one based on ecological constraints and the other based on queen-worker competition. Received: 20 October 1999 / Received in revised form: 18 December 1999 / Accepted: 23 January 2000