A non-land policy for global sustainable land use?

What are new ways and future options for the international governance of sustainable land use? Effective policies towards more sustainable land use should not only deal with land and soil. These policies need to address various drivers and different contexts in an integrated manner

Agricultural biomass as provisioning ecosystem service: quantification of energy flows

Agro-ecosystems supply provisioning, regulating and cultural services to human society. This study focuses on the agro-ecosystem provisioning services regarding the production of agricultural biomass. These services strongly respond to the socio-economic demands of human beings, and are characterised by an injection of energy in the ecosystems production cycle which is often exceeding the ecological capacity of the ecosystem, i.e. the overall ability of the ecosystem to produce goods and services linked to its bio-physical structure and processes that take place during the agricultural production. Agricultural production is identified as ecosystem service in widely recognised ecosystem service frameworks, but currently there is no clear agreement within the scientific and policy communities on how the ecological-socio-economic flow linked to this provisioning service should be assessed, beyond a mere accounting of yields. This study attempts to provide a new insight to this issue by proposing an approach based on the energy budget, which takes into consideration the energy needed by the ecosystem to supply the service. The approach is based on the concepts of Energy Return on Investment (EROI) and Net Energy Balance (NEB), and considers different bio-physical structures and processes of agro-ecosystems. The work is structured in three parts: the first aims at estimating inputs (machinery, seeds, fertilizers, irrigation, labour) in energy terms; the second at estimating biomass output in energy terms; the third to compare actual agricultural production with three reference scenarios encompassing a range of human input (no input – low input – high input scenarios). Results show that in general terms cereal and grassland systems have the largest energy gains (both in terms of EROI and NEB). Such systems are characterised by a lower economic value of their output compared to other producing systems such as fruits, which have lower energy gains but a higher embodied energy, which is recognized in the market as valuable. Comparison of actual production systems with the high input scenario confirms that current production in Europe is already highly intensive, and that increasing the energy input would not improve the efficiency of the conversion of such additional energy into biomass. Overall, the proposed approach seems a useful tool to identify which are the factors in the agricultural production process that could be modified to improve the energy efficiency in agricultural systems and the sustainability of their production. This study can be considered as a first step in the assessment of the total energy balance of the agro-ecosystem. In fact it deals with the quantification of energy regarding human inputs and the corresponding output and further analysis should address crucial issues such as the quality of the energy and the embodied energy in the plant production, which will help to understand the full complexity of the agro-ecosystemJRC.H.4-Monitoring Agricultural Resource

Effects of habitat structure and shrub encroachment on bird species diversity in arid savanna in Northern Cape province, South Africa

Bird community diversity was assessed in semi-arid savanna in the Northern Cape province of South Africa and related to vegetation diversity and foliage height diversity. As this is an area in which shrub encroachment is common, the effects of shrub or bush encroachment on bird species diversity were specifically addressed. An experiment in which the dominant encroaching species, Acacia mellifera, was removed from ten 1 ha plots was used and compared with ten controls. A strong positive association with foliage height diversity was shown. No effect of experimental removal of the dominant encroacher, A. mellifera, on bird species diversity or species richness was found. However, four species increased in relative abundance in cut plots and two species decreased in relative abundance in these plots. Ostrich 2008, 79(2): 133–14

European Union Policy on Bioenergy and the Role of Sustainability Criteria and Certification Systems

The EU has set ambitious targets to raise the share of renewable energies, particularly biofuels. With an increasingly controversial public debate and more scientific evidence about the downsites of biofuels, recently the European Unions biofuel targets have been bound to the condition that they have to be produced sustainable. Therefore the European Commission is currently developing sustainability criteria for biofuels.Establishing certification schemes is a possible strategy to ensure that bioenergy crops are produced in a sustainable manner. However, many questions with regard to the design and implementation of sustainability criteria and certification schemes remain unsolved.This article discusses the role that bioenergy plays in the European policy context and the approach the EU is currently following in order to ensure the sustainability of biofuels. It addresses the limits of the chosen approach, concluding that certification schemes can not serve as the only safeguard for sustainable bioenergy, but need to be complemented by other tools and policies.

A Meta Analysis on Farm-Level Costs and Benefits of GM Crops

This paper reviews the evidence on the socio-economic impacts of GM crops and analyzes whether there are patterns across space and time. To this end, we investigate the effect of GM crops on farm-level costs and benefits using global data from more than one decade of field trials and surveys. More specifically, we analyze the effects of GM-crops on crop yields, seed costs, pesticide costs, and management and labor costs and finally gross margins. Based on collected data from studies on Bt cotton and Bt maize, statistical analyses are conducted to estimate the effect of GM crop adoption on these parameters. Our results show that, compared to conventional crops, GM crops can lead to yield increases and can lead to reductions in the costs of pesticide application, whereas seed costs are usually substantially higher. Thus, the results presented here do support the contention that the adoption of GM crops leads on average to a higher economic performance, which is also underlined by the high adoption rates for GM crops in a number of countries. However, the kind and magnitude of benefits from GM crops are very heterogeneous between countries and regions, particularly due to differences in pest pressure and pest management practices. Countries with poor pest management practices benefited most from a reduction in yield losses, whereas other countries benefited from cost reductions. However, our study also reveals limitations for meta-analyses on farm-level costs and benefits of GM crops. In particular, published data are skewed towards some countries and the employed individual studies rely on different assumptions, purposes and methodologies (e.g., surveys and field trials). Furthermore, a summary of several (often) short-term individual studies may not necessarily capture long-term effects of GM crop adoption

A Meta Analysis on Farm-Level Costs and Benefits of GM Crops

This paper reviews the evidence on the socio-economic impacts of GM crops and analyzes whether there are patterns across space and time. To this end, we investigate the effect of GM crops on farm-level costs and benefits using global data from more than one decade of field trials and surveys. More specifically, we analyze the effects of GM-crops on crop yields, seed costs, pesticide costs, and management and labor costs and finally gross margins. Based on collected data from studies on Bt cotton and Bt maize, statistical analyses are conducted to estimate the effect of GM crop adoption on these parameters. Our results show that, compared to conventional crops, GM crops can lead to yield increases and can lead to reductions in the costs of pesticide application, whereas seed costs are usually substantially higher. Thus, the results presented here do support the contention that the adoption of GM crops leads on average to a higher economic performance, which is also underlined by the high adoption rates for GM crops in a number of countries. However, the kind and magnitude of benefits from GM crops are very heterogeneous between countries and regions, particularly due to differences in pest pressure and pest management practices. Countries with poor pest management practices benefited most from a reduction in yield losses, whereas other countries benefited from cost reductions. However, our study also reveals limitations for meta-analyses on farm-level costs and benefits of GM crops. In particular, published data are skewed towards some countries and the employed individual studies rely on different assumptions, purposes and methodologies (e.g., surveys and field trials). Furthermore, a summary of several (often) short-term individual studies may not necessarily capture long-term effects of GM crop adoption.biotechnology; GM crops; food security; technological change