E. Ceotto.

Bioresource technology, Vol. 96, No. 2, Jan 2005, pp. 191-196.

This paper focuses on the benefits of an efficient use of animal waste from the standpoint of curbing the rise of anthropogenic carbon dioxide (CO sub(2)) in the atmosphere. An effective use of animal waste resources might provide a partial, but still important, contribution in reducing net CO sub(2) emissions. In particular: the fulfilment of nutrient requirements of crop plants growing in non-limiting conditions and thus sequestering CO sub(2) at their potential level; the chance of diminishing the use of fossil energy, and related CO sub(2) emissions, required for manufacturing industrial fertilizers; the possibility of enhancing carbon sequestration in agricultural soils by the application of farmyard manure. The future success of agriculture in providing these ecosystem services can only be achieved with a changed social awareness of the links between sustainable land use and global environmental change.

J. Faithful and W. Finlayson.

Marine pollution bulletin, Vol. 51, No. 1-4, 2005, pp. 99-112.

A number of studies in north Queensland over the past two decades have concluded that large amounts of nutrients and sediments are exported from agricultural watersheds, particularly during wet season rainfall events. With the co-operation of a number of growers, runoff from Queensland Wet Tropics banana and cane farm paddocks in two distinct tropical river catchments was examined to provide an estimate of nutrient and sediment concentrations and export, with comparison to water quality of flow through a small urban lakes system. Median total nitrogen concentrations in cane drainage runoff (3110 mu g N/L) were higher than for banana paddock drainage (2580 mu g N/L), although the maximum concentration was recorded from a banana paddock (20, 900 mu g N/L). Nitrogen losses during post-event drainage flow were supplemented by high proportions of NO sub(X) (nitrate + nitrite) sourced from groundwater inputs. Banana paddocks had the highest maximum and median total phosphorus and TSS concentrations (5120 and 286 mu g P/L, and 7250 and 75 mg/L respectively) compared to the cane farms (1430 and 50 mu g P/L, and 1840 and 14 mg/L respectively). The higher phosphorus and TSS concentrations in the banana runoff were attributed to higher paddock slopes and a greater proportion of exposed ground surface during the wet season. Highest nutrient and TSS concentrations corresponded with samples collected near the peak discharge periods; however, the rising stage of the drainage flows, where the highest nutrient and TSS concentrations are often reported, were difficult to target because of the manual sampling strategy used. This study shows that high concentrations of nutrients and TSS occur in the runoff from cane and banana paddocks. Median total nitrogen, total phosphorus and TSS concentrations in flow through the urban lakes were 369 mu g N/L, 16 mu g P/L and 11 mg/L, respectively. Flux estimates of 9.2 kg N, 0.8 kg P and 126 kg TSS/ha were determined for drainage runoff from a banana paddock during a single intensive storm event.

L. N. Gachimbi, H. van Keulen and E. G. Thuranira, et al.

Land Use Policy, Vol. 22, No. 1, Jan 2005, pp. 13-22.

A total of 74 farms were selected from Machakos, Mwingi and Makueni districts in Kenya, using participatory techniques and classified in three categories on the basis of soil fertility management (low level, medium and high level). Soil fertility management was monitored, using the NUTrient MONitoring methodology, which appears a suitable and appropriate tool for the diagnostic phase of Farming System Analysis and Design in Arid and Semi-Arid Lands of Kenya. The participatory inventory and monitoring procedures applied, involving the farmers in the analysis of their own situation, forced the farmers to think about the processes and flows associated with the nutrient balances and the associated consequences for the quality of their soil resource base. Farmers' performance during the feedback, through farmers' workshops, of the results of soil analyses and the discussion on possible solutions for the identified problems, creates confidence that in the participatory learning and action phase, farmers will be equally involved and willing to adopt suggested adaptations. The first results of the quantitative analyses of nutrient balances at farm level show that farm balances for NPK are negative. This is in agreement with earlier work in the high-potential areas of Kenya and elsewhere in East Africa, as well as those from semi-arid regions in West Africa. It has been shown that client characterisation, as an emerging component of a research approach towards design of sustainable agricultural production systems, helps in identifying major potential recommendation domains and related research and development problems and opportunities, and potential interventions on which to focus the research agenda.

B. D. Hahn, F. D. Richardson, M. T. Hoffman, R. Roberts, S. W. Todd and P. J. Carrick.

Ecological Modelling, Vol. 183, No. 2-3, Apr 2005, pp. 211-230.

The communal areas of the semi-arid (200 mm) winter-rainfall Namaqualand region of South Africa are heavily utilised by a large number of subsistence farmers who keep sheep and goats. For several decades, farmers have maintained, on average, more than twice the number of animals on the rangeland than the number recommended by the Department of Agriculture for neighbouring commercial enterprises. As a result of the continuous high stocking densities, significant changes in the vegetation have taken place. Farmers are now heavily reliant on an annual flush of vegetation following winter rains to keep their livestock alive. Using a combination of empirical data and consensus agreement, a computer model is developed to describe the long-term climate, livestock and vegetation interactions on the communal rangelands and to investigate the impacts of a range of management strategies. The model suggests that the system (including livestock) is sustainable although not stable, and that its sustainability could be due to climatic variability. The model supports the view that when livestock numbers vary in a manner consistent with recorded observations herbivory has little long-term impact on productivity of the system. This supports recent views of rangelands in semi-arid and arid environments where non-equilibrium conditions are thought to dominate ecosystem processes.

D. G. Hole, A. J. Perkins, J. D. Wilson, I. H. Alexander, P. V. Grice and A. D. Evans.

Biological Conservation, Vol. 122, No. 1, Mar 2005, pp. 113-130.

The intensification and expansion of modern agriculture is amongst the greatest current threats to worldwide biodiversity. Over the last quarter of the 20th century, dramatic declines in both range and abundance of many species associated with farmland have been reported in Europe, leading to growing concern over the sustainability of current intensive farming practices. Purportedly 'sustainable' farming systems such as organic farming are now seen by many as a potential solution to this continued loss of biodiversity and receive substantial support in the form of subsidy payments through EU and national government legislation. This paper assesses the impacts on biodiversity of organic farming, relative to conventional agriculture, through a review of comparative studies of the two systems, in order to determine whether it can deliver on the biodiversity benefits its proponents claim. It identifies a wide range of taxa, including birds and mammals, invertebrates and arable flora, that benefit from organic management through increases in abundance and/or species richness. It also highlights three broad management practices (prohibition/reduced use of chemical pesticides and inorganic fertilisers; sympathetic management of non-cropped habitats; and preservation of mixed farming) that are largely intrinsic (but not exclusive) to organic farming, and that are particularly beneficial for farmland wildlife. However, the review also draws attention to four key issues: (1) It remains unclear whether a 'holistic' whole-farm approach (i.e. organic) provides greater benefits to biodiversity than carefully targeted prescriptions applied to relatively small areas of cropped and/or non-cropped habitats within conventional agriculture (i.e. agri- environment schemes); (2) Many comparative studies encounter methodological problems, limiting their ability to draw quantitative conclusions; (3) Our knowledge of the impacts of organic farming in pastoral and upland agriculture is limited; (4) There remains a pressing need for longitudinal, system-level studies in order to address these issues and to fill in the gaps in our knowledge of the impacts of organic farming, before a full appraisal of its potential role in biodiversity conservation in agroecosystems can be made.

S. Kamel and C. Dahl.

Energy (Oxford), Vol. 30, No. 8, Jun 2005, pp. 1271-1281.

Egypt has embarked on an ambitious desert land reclamation program in order to increase total food production. Energy planners for these desert agriculture locations have chosen diesel generation power technology because minimization of the initial capital cost of a power supply system is their top priority. This heavy reliance on diesel generation has negative effects on the surrounding environment including soil, groundwater, and air pollution. Although good solar and wind resource prospects exist for the use of cleaner hybrid power systems in certain desert locations, little research has been done to investigate the economic potential of such systems in Egypt's desert agriculture sector. Using optimization software, we assess the economics of hybrid power systems versus the present diesel generation technology in a remote agricultural development area. We also consider the emission reduction advantages of using hybrid systems. Interestingly enough, optimization results show that hybrid systems are less costly than diesel generation from a net present cost perspective even with the high diesel fuel price subsidies. Since hybrids are also more environmentally friendly, they represent a strong step towards achieving sustainable desert agriculture.

L. S. Kriflik and H. Yeatman.

Health, Risk & Society, Vol. 7, No. 1, Mar 2005, pp. 11-24.

Health campaigns have focused on lifestyle decisions such as physical inactivity, diet and smoking to minimise health risks. The links between health, environmental sustainability and consumer food choices have less prominence. Reported here are Australian consumer perceptions of environmental health issues related to the food system. Interviews with 26 participants explored the environmental implications of food choices. Concerns included conflicting information, related health risks, and the blaming of individuals for `poor' choices. Participants recognised that focussing on the individual overlooked the structural context of food production. They requested information about food production processes to assist decision-making and identified the need for an influential body to advocate for their interests in food production decisions. The results indicate a need for government, industry and consumer collaboration to develop and implement practical communication strategies about food production for communities.

Dong Lu, Liang-gang Zong, Xing-ji Xiao, Yong-gang Yang, Ze-jiang Zhou and Yun-guan Xi.

Journal of Agro-Environment Science, Vol. 24, No. 1, 20 Feb 2005, pp. 143-147.

To assess the effect of organic farming on soil heavy metals, concentrations of heavy metals including Cu, Zn, Pb, Cd, Cr and Ni were detected for the soils under the practices of organic and conventional farming. Three sites in eastern China where organic farming has been performed are involved, including organic spring onion and cauliflower in Xinghui of Fengxian County, Shanghai City, organic rice farms in Lishui County of Jiangsu Province, and organic kiwifruit orchards in Yuexi County of Anhui Province. The results indicate that concentrations of the six heavy metals in soils accord with the first class standard of Environmental Quality Criterion in Soil (GB15618-1995) for the three sites. Compared with the conventional farming, the concentrations of Pb, Cd and Ni decreased remarkably, while that of Cu increased obviously in the organic farming soils. The concentrations of Cr and Zn in the organic farming soils are a little higher than that in the conventional farming in the plots of Fengxian and Lishui counties. The increase of Cu, Cr and Zn might attribute to the application of chicken and pig manure for some heavy metals are feedstuff additives. By contrast, the concentrations of Cr and Zn are lower in the organic kiwifruit orchards in Yuexi County where green manure is usually amended as organic fertilizer. These suggest that the quality of organic fertilizers should be carefully controlled to promote the development of organic agriculture in China.

V. Mintcheva.

Journal of Cleaner Production, Vol. 13, No. 7, Jun 2005, pp. 717-731.

Following the recent developments in supply chain management and environmental policy integration, it became evident that for successfully addressing the environmental challenges a holistic approach is necessary. After identifying a lack of sufficient information on the environmental performance and the uptake of the respective policy measures from food supply chain perspective, a research has been undertaken for designing indicators on these issues. As a concrete case, a tomato ketchup chain and the Integrated Product Policy framework have been examined. This paper presents the results of the study performed. After identifying and analysing the respective policy measures, a set of environmental indicators have been proposed and a discussion on their applicability and role in policy-making is raised.

G. A. O'Connor, H. A. Elliott and N. T. Basta, et al.

Journal of environmental quality, Vol. 34, No. 1, Jan-Feb 2005, pp. 7-17.

Man has land-applied societal nonhazardous wastes for centuries as a means of disposal and to improve the soil via the recycling of nutrients and the addition of organic matter. Nonhazardous wastes include a vast array of materials, including manures, biosolids, composts, wastewater effluents, food-processing wastes, industrial by-products; these are collectively referred to herein as residuals. Because of economic restraints and environmental concerns about land-filling and incineration, interest in land application continues to grow. A major lesson that has been learned, however, is that the traditional definition of land application that emphasizes applying residuals to land in a manner that protects human and animal health, safeguards soil and water resources, and maintains long-term ecosystem quality is incomplete unless the earning of public trust in the practices is included. This overview provides an introduction to a subset of papers and posters presented at the conference, "Sustainable Land Application," held in Orlando, FL, in January 2004. The USEPA, USDA, and multiple national and state organizations with interest in, and/or responsibilities for, ensuring the sustainability of the practice sponsored the conference. The overriding conference objectives were to highlight significant developments in land treatment theory and practice, and to identify future research needs to address critical gaps in the knowledge base that must be addressed to ensure sustainable land application of residuals.

S. Payraudeau and H. M. G. Van der Werf.

Agriculture, Ecosystems & Environment, Vol. 107, No. 1, May 2005, pp. 1-19.

The methods currently used for assessing the environmental impact of agriculture on the scale of a farming region cover a wide range of objectives, users and concepts. To illustrate this variety, this article provides an analysis of six main types of method: environmental risk mapping, life cycle analysis, environmental impact assessment, multi-agent system, linear programming and agro-environmental indicators. Eleven case studies, in which one of the six methods was applied, are used as data in this review. All methods are based on a set of environmental objectives. Some methods also take account of economic and social objectives to produce a more wide-ranging assessment of the sustainability of the agricultural system studied. Each method relies on indicators serving as criteria to evaluate whether the objectives have been attained. These indicators take account of local impacts such as noise, regional impacts such as eutrophication, or global impacts like the greenhouse effect. The characteristics required to develop a method for the environmental impact assessment of a farming region are discussed. The analysis of the interactions between farms is indispensable at this scale of analysis. Indicators based on the environmental effects of farming practices should take precedence over those based on the practices themselves, which do not provide a direct evaluation of environmental impact. Indicators which express an impact both per kg of product and per unit of land area used bring together the essential functions of agriculture, namely production and the occupation of the countryside. The assessment methods should include an analysis of the uncertainty associated with the results. Lastly, the method should be validated with respect to (i) the conception of the method and its indicators, (ii) the consistency of the values of the indicators in relation to observed values, and finally (iii) the suitability of the indicators and more generally of the assessment method for the end users.

P. Ramesh, M. Singh and A. S. Rao.

Current science, Vol. 88, No. 4, 25 Feb 2005, pp. 561-568.

Increasing consciousness about conservation of environment as well as health hazards associated with agrochemicals and consumers' preference to safe and hazard-free food are the major factors that lead to the growing interest in alternate forms of agriculture in the world. Organic agriculture is one among the broad spectrum of production methods that are supportive of the environment. The demand for organic food is steadily increasing both in the developed and developing countries with an annual average growth rate of 20-25%. Organic agriculture, without doubt, is one of the fastest-growing sectors of agricultural production. However, there are certain issues that should be clarified before we go for a large-scale conversion to organic agriculture. The most important issues are - Can organic farming produce enough food for everybody? Is it possible to meet the nutrient requirements of crops entirely from organic sources? Are there any significant environmental benefits that accrue from organic farming? Is the food produced by organic farming superior in quality? Is it economically feasible? In this article, we review these aspects of organic farming. In India, vast stretches of arable land, which are mainly rain-fed and found in the Northeastern region where negligible amount of fertilizers and pesticides are being used and have low productivity, could be exploited as potential areas for organic agriculture. Considering the potential environmental benefits of organic production and its compatibility with integrated agricultural approaches to rural development, organic agriculture may be considered as a development vehicle for developing countries like India, in particular.

Damodar D. Reddy, Subba A. Rao and Muneshwar Singh.

Journal of Plant Nutrition and Soil Science, Vol. 168, No. 2, Apr 2005, pp. 241-247.

With the emphasis on sustainable agriculture, attention has been increasingly turning to recycling of crop residues as a component of fertility management strategies for tropical soils. We assessed the effects of soybean residue (SR) and wheat residue (WR) applied either alone or in combination with fertilizer P (FP) on dynamics of labile P, distribution of P fractions, and P sorption in a semiarid tropical Alfisol by conducting a 16 w long incubation experiment. The amount of P added through crop residues, FP or their combinations was kept constant at 10 mg P (kg soil) super(-1). Addition of SR or WR resulted in net increase of labile inorganic (P sub(i)) and organic P (P sub(o)) and microbial P throughout the incubation period, except that the WR decreased labile P sub(i) during first 2 w due to P sub(i) immobilization. The P immobilization associated with WR addition was, however, offset when fertilizer P was combined with WR. Generally, the increases in labile-P fractions were larger with the SR and SR+FP than with the WR and WR+FP. The sequential fractionation of soil P at the end of 16 w indicated that a major part of added fertilizer P transformed into moderately labile and stable P fractions as evident from the increased NaOH-P sub(i) and HCl-P in the FP treatment. In contrast, the addition of SR and WR alone or in combination with FP favored a build-up in NaHCO sub(3)-P sub(i) and-P sub(o) and NaOH-P sub(o) fractions while causing a decrease in NaOH-P sub(i) and HCl-P fractions. The addition of these crop residues also effectively decreased the P-sorption capacity and hence reduced the standard P requirement of the soil (i.e. the amount of P required to maintain optimum solution P concentration of 0.2 mg P l super(-1)) by 24%-43%. Results of the study, thus, imply that soybean and wheat crop residues have the potential to improve P fertility of Alfisols by decreasing P-sorption capacity and by redistributing soil P in favor of labile-P fractions and promoting accretion of organic P.

Yeqiao Wang, J. Tobey and G. Bonynge, et al.

Coastal Management, Vol. 33, No. 1, Jan-Mar 2005, pp. 87-99.

This article provides the first comprehensive scientific data on land-use and land-cover change in the coastal zone of Tanzania over the 1990 and 2000 time periods. The research was part of an African region initiative to demonstrate the practical application of geographic information for sustainable development. Remotely sensed images from close to 1990 Landsat Thematic Mapper (TM) sensor and 2000 Landsat-7 Enhanced Thematic Mapper Plus (ETM+) sensor and geographic information system (GIS) technologies are applied to discern changes in land cover and land use along the mainland Tanzania coast. Change detection results show that urban land area has increased dramatically. Mangrove forest area declined modestly, but field verification shows severe deterioration of their conditions near urban areas. While the area of dense woodland decreased, the area of open woodland and the area of woodland interspersed with agriculture increased. This study demonstrates how geospatial information science and technologies provide critical information and tools for coastal resource managers who work at the crossroads of resource use, land-cover change, poverty alleviation, and environmental management.