Potential for clean yam minisett production by resource-poor farmers in the middle-belt of Nigeria

Yarn minisett technique (YMT) has been promoted throughout West Africa since the 1980s as a sustainable means of producing clean yarn planting material, but adoption of the technique is Often reported as being patchy at best. While there has been much research Oil the factors that influence adoption of the technique, there have been no attempts to assess its economic viability under 'farmer-managed' as distinct from 'on station' conditions. The present paper describes the results of farmer-managed trials employing the YMT (white yarn: Dioscorea rotundata) at two villages in Igalaland, Kogi State, Nigeria. One of the villages (Edeke) is on the banks of the River Niger and represents it specialist yarn environment, whereas the other village (Ekwuloko) is inland, where farmers employ a more general cropping system. Four farmers were selected in each of the two villages and asked to plant a trial comprising two varieties of yam, their popular local variety its well its another variety grown in other parts of Igalaland, and to treat yarn setts (80-100 g) with either woodash or insecticide/nematicide + fungicide mix (chemical treatment). Results suggest that while chemical sett treatment increased yield and hence gross margin compared with woodash, if household labour is costed then YMT is not economically viable. However, the specialist yarn growers of Edeke were far more positive about the use of YMT as they tended to keep the yarn seed tubers for planting rather than sell them. Thus, great care needs to be taken with planning adoption surveys on the assumption that all farmers should adopt a technology.

Social interactions and resource ownership in two private protected areas of Paraguay

This paper describes the results of field research to dissect how social interactions differ between two reserves in Paraguay having very different styles of governance. The two reserves were Mbaracayu Natural Forest Reserve (Reserva Natural del Bosque de Mbaracayti, RNBM) and San Rafael Managed Resource Reserve (Reserva de Recursos Manejados San Rafael, RRMSR). RNBM is a private reserve owned by a non-governmental organisation. while RRNISR is a publicly-managed reserve, albeit with a substantial degree of private land ownership. Both reserves are intended to protect Atlantic Forest, one of the five world biodiversity 'hotspots', and also one of the most highly threatened. Each reserve and its buffer zone comprises a set of stakeholders, including indigenous communities and farmers, and the paper explores the interactions between these and the management regime. Indeed, while the management regimes of the two reserves are different, one being highly top-down (RNBM) and the other more socially inclusive (RRMSR), the issues that they have to deal with are much the same. However, while both management regimes will readily acknowledge the need to address poverty, inequality appears to be a far more sensitive issue. Whereas this may be expected for the privately-owned RNBM it is perhaps more surprising in RRNISR even when allowing for the fact that much of the land in the latter is in private hands. It is argued that the origins of this sensitivity rest within the broader features of Paraguayan society, and the prevalence of private land ownership. Yet ironically, it is the inequality in land ownership that is perhaps the most significant threat to conservation in both reserves. Therefore, while reserve-level analyses can provide some insight into the driving forces at play in the interaction between conservation and sustainable management, larger scales may be necessary to gain a fuller appreciation of the dynamics operating at site level. Even in a society with a history of centralised control these dynamics may be surprising. (c) 2005 Elsevier Ltd. All rights reserved.

A Glacial Geomorphological Map of Victoria Island, Canadian Arctic

Victoria Island lies at the north-western extremity of the region covered by the vast North American Laurentide Ice Sheet (LIS) in the Canadian Arctic Archipelago. This area is significant because it linked the interior of the LIS to the Arctic Ocean, probably via a number of ice streams. Victoria Island, however, exhibits a remarkably complex glacial landscape, with several successive generations of ice flow indicators superimposed on top of each other and often at abrupt (90 degrees) angles. This complexity represents a major challenge to those attempting to produce a detailed reconstruction of the glacial history of the region. This paper presents a map of the glacial geomorphology of Victoria Island. The map is based on analysis of Landsat Enhanced Thematic Plus (ETM+) satellite imagery and contains over 58,000 individual glacial features which include: glacial lineations, moraines (terminal, lateral, subglacial shear margin), hummocky moraine, ribbed moraine, eskers, glaciofluvial deposits, large meltwater channels, and raised shorelines. The glacial features reveal marked changes in ice flow direction and vigour over time. Moreover, the glacial geomorphology indicates a non-steady withdrawal of ice during deglaciation, with rapidly flowing ice streams focussed into the inter-island troughs and several successively younger flow patterns superimposed on older ones. It is hoped that detailed analysis of this map will lead to an improved reconstruction of the glacial history of this area which will provide other important insights, for example, with respect to the interactions between ice streaming, deglaciation and Arctic Ocean meltwater events.

Farming systems methodology for efficient resource management at the farm level: a review from an Indian perspective

Farming systems research is a multi-disciplinary holistic approach to solve the problems of small farms. Small and marginal farmers are the core of the Indian rural economy Constituting 0.80 of the total farming community but possessing only 0.36 of the total operational land. The declining trend of per capita land availability poses a serious challenge to the sustainability and profitability of farming. Under such conditions, it is appropriate to integrate land-based enterprises such as dairy, fishery, poultry, duckery, apiary, field and horticultural cropping within the farm, with the objective of generating adequate income and employment for these small and marginal farmers Under a set of farm constraints and varying levels of resource availability and Opportunity. The integration of different farm enterprises can be achieved with the help of a linear programming model. For the current review, integrated farming systems models were developed, by Way Of illustration, for the marginal, small, medium and large farms of eastern India using linear programming. Risk analyses were carried out for different levels of income and enterprise combinations. The fishery enterprise was shown to be less risk-prone whereas the crop enterprise involved greater risk. In general, the degree of risk increased with the increasing level of income. With increase in farm income and risk level, the resource use efficiency increased. Medium and large farms proved to be more profitable than small and marginal farms with higher level of resource use efficiency and return per Indian rupee (Rs) invested. Among the different enterprises of integrated farming systems, a chain of interaction and resource flow was observed. In order to make fanning profitable and improve resource use efficiency at the farm level, the synergy among interacting components of farming systems should be exploited. In the process of technology generation, transfer and other developmental efforts at the farm level (contrary to the discipline and commodity-based approaches which have a tendency to be piecemeal and in isolation), it is desirable to place a whole-farm scenario before the farmers to enhance their farm income, thereby motivating them towards more efficient and sustainable fanning.

Arthropod community structure in pastures of an island archipelago (Azores): looking for local-regional species richness patterns at fine-scales

The arthropod species richness of pastures in three Azorean islands was used to examine the relationship between local and regional species richness over two years. Two groups of arthropods, spiders and sucking insects, representing two functionally different but common groups of pasture invertebrates were investigated. The local-regional species richness relationship was assessed over relatively fine scales: quadrats (= local scale) and within pastures (= regional scale). Mean plot species richness was used as a measure of local species richness (= alpha diversity) and regional species richness was estimated at the pasture level (= gamma diversity) with the 'first-order-Jackknife' estimator. Three related issues were addressed: (i) the role of estimated regional species richness and variables operating at the local scale (vegetation structure and diversity) in determining local species richness; (ii) quantification of the relative contributions of alpha and beta diversity to regional diversity using additive partitioning; and (iii) the occurrence of consistent patterns in different years by analysing independently between-year data. Species assemblages of spiders were saturated at the local scale (similar local species richness and increasing beta-diversity in richer regions) and were more dependent on vegetational structure than regional species richness. Sucking insect herbivores, by contrast, exhibited a linear relationship between local and regional species richness, consistent with the proportional sampling model. The patterns were consistent between years. These results imply that for spiders local processes are important, with assemblages in a particular patch being constrained by habitat structure. In contrast, for sucking insects, local processes may be insignificant in structuring communities.

Leaving final-cut grass silage in situ overwinter as a seed resource for declining farmland birds

The loss of seed-rich wintering habitats has been a major contributory cause of farmland bird population declines in western Europe. Agricultural grasslands are particularly poor winter foraging habitats for granivorous birds, which have declined most in the pastoral farming regions of western Britain. We describe an experiment to test the utility of fertile ryegrass (Lolium) swards as a potentially rich source of winter seed for declining farmland birds. Four patches of final-cut grass silage were allowed to set seed and were left in situ overwinter. Half of each patch was lightly aftermath grazed in an attempt to increase the accessibility of the seed to foraging birds and reduce the perceived predation risk. Large numbers of yellowhammers (Emberiza citrinella) and reed buntings (E. schoeniclus) foraged on the seeded plots throughout the winter. They preferred to forage on ungrazed seeded plots, where the accumulation of senescent foliage resulted in a 14% average loss in silage yield in the following season. However, seed produced on the plots also led to sward regeneration, increasing subsequent yields on some plots. The technique offers clear benefits as a potential future agri-environment measure for declining granivorous birds, with wide applicability, but requires further development to minimise sward damage and costs to the farmer. Autumn grazing should reduce sward damage, but at the cost of reduced usage by buntings. Using the technique just prior to reseeding would be one way of avoiding any costs of sward damage.