Jan Verhagen

The development and climate nexus: the case of sub-Saharan Africa

Abstract This paper explores an alternative approach to future climate policies in developing countries. Although climate change seems marginal compared to the pressing issues of poverty alleviation and economic development, it is becoming clear that the realisation of development goals may be hampered by climate change. However, development can be shaped in such a way as to achieve its goals and at the same time reduce vulnerability to climate change, thereby facilitating sustainable development that realises economic, social, local and global environmental goals. This approach has been coined the ‘development first approach’, in which a future climate regime should focus on development strategies with ancillary climate benefits and increase the capability of developing countries to implement these. This is anticipated to offer a possible positive way out of the current deadlock between North and South in the climate negotiations. First, elements are presented for an integrated approach to development and climate; second, the approach is elaborated for food and energy security in sub-Saharan Africa; and third, possibilities are outlined for international mechanisms to support such integrated development and climate strategies.

Integrating development and climate policies: national and international benefits

What lessons for policy makers at national and international level can be drawn from the growing experiences of reconciling development and climate change? The key to achieving this is to approach the problem from the development perspective, since that is where in most countries the priority lies. Current knowledge on how to realize the benefits of such an integrated approach is assessed. The focus is on the main national development priorities, such as poverty reduction, disaster reduction, rural development, energy supply and transportation. Barriers and promising approaches are identified, based on the experience gained in several countries. The potential is explored for enhancing the global impact of such integrated approaches through replication of national experiences, supported by international organizations. Opportunities for large-scale initiatives are considered at national or regional level. The role of international agreements in fostering integrated development and climate policies is analysed, showing opportunities for achieving large co-benefits for addressing climate change by making use of existing policy frameworks for development and going beyond the UNFCCC framework.

Olivine Weathering in Soil, and Its Effects on Growth and Nutrient Uptake in Ryegrass (lolium perenne L.): A Pot Experiment

Mineral carbonation of basic silicate minerals regulates atmospheric CO2 on geological time scales by locking up carbon. Mining and spreading onto the earths surface of fast-weathering silicates, such as olivine, has been proposed to speed up this natural CO2 sequestration (‘enhanced weathering’). While agriculture may offer an existing infrastructure, weathering rate and impacts on soil and plant are largely unknown. Our objectives were to assess weathering of olivine in soil, and its effects on plant growth and nutrient uptake. In a pot experiment with perennial ryegrass (Lolium perenne L.), weathering during 32 weeks was inferred from bioavailability of magnesium (Mg) in soil and plant. Olivine doses were equivalent to 1630 (OLIV1), 8150, 40700 and 204000 (OLIV4) kg ha−1. Alternatively, the soluble Mg salt kieserite was applied for reference. Olivine increased plant growth (+15.6%) and plant K concentration (+16.5%) in OLIV4. At all doses, olivine increased bioavailability of Mg and Ni in soil, as well as uptake of Mg, Si and Ni in plants. Olivine suppressed Ca uptake. Weathering estimated from a Mg balance was equivalent to 240 kg ha−1 (14.8% of dose, OLIV1) to 2240 kg ha−1 (1.1%, OLIV4). This corresponds to gross CO2 sequestration of 290 to 2690 kg ha−1 (29 103 to 269 103 kg km−2.) Alternatively, weathering estimated from similarity with kieserite treatments ranged from 13% to 58% for OLIV1. The Olsen model for olivine carbonation predicted 4.0% to 9.0% weathering for our case, independent of olivine dose. Our % values observed at high doses were smaller than this, suggesting negative feedbacks in soil. Yet, weathering appears fast enough to support the ‘enhanced weathering’ concept. In agriculture, olivine doses must remain within limits to avoid imbalances in plant nutrition, notably at low Ca availability; and to avoid Ni accumulation in soil and crop.

Science for agriculture and rural development in low-income countries

Preface, Executive Summary, List of Abbreviations. 1. Agriculture in a dynamic world, R.P. Roetter, H. Van Keulen, J. Verhagen and M. Kuiper. 2. Historical context of agricultural development, H. Van Keulen. 3. Food security, R.P. Roetter and H. Van Keulen. 4. Agriculture and environment, J. Verhagen, H. Wosten and A. De Jager. 5. Rural livelihoods: Interplay between farm activities, non-farm activities and the resource base, M. Kuiper, G. Meijerink and D. Eaton. 6. Lessons learned, R.P. Roetter, M. Kuiper, H. Van Keulen, J. Verhagen and G. Meijerink. 7. Project assessments, A. De Jager, C. Ritsema, M. Mosugu, G. Meijerink, P. Van den Brink, H. Van den Bosch, E. Van der Elsen, R.P. Roetter, S. Van Wijk, S. Verzandvoort-Van Dijck, C.A. Van Diepen and B. Kamphuis. Project NUTSAL, Project EroChinut, Project PIMEA, Project INMASP, Project MAMAS, Project EROAHI, Project Himalaya, Project IRMLA, Project VEGSYS, Project VINVAL, Project RMO-Beijing, Project SEARUSYN

Climate change and drought risks for agriculture

Changes in rainfall patterns and risk of crop failure are discussed in this chapter. Agriculture is by far the most important economic activity in the region. The success of this economic activity relies heavily on water availability during the growing season. For rainfed production systems timing and the amount of precipitation determine to a large extent the success of the growing season. The projected changes in the variability and total amount of rainfall are expected to worsen the situation.

Surface water sanitation and biomass production in a large constructed wetland in the Netherlands

In Western-Europe, agricultural practices have contributed to environmental problems such as eutrophication of surface and ground water, flooding, drought and desiccation of surrounding natural habitats. Solutions that reduce the impact of these problems are urgently needed. Common reed (Phragmites australis) is capable of sanitizing surface water and may function as green energy source because of its high productivity. Here, the results of an experiment in a constructed wetland in the Netherlands are presented where two different sanitation treatments were compared. Depending on the residence time and volume per unit area, reed is capable to reduce the total amount of nitrogen in the water with average efficiencies from 32 to 47% and the total amount of phosphorous with 27–45%. Although biomass production still varies largely between different parts of the constructed wetland, a rapid increase in biomass was observed since planting. Constructed wetlands with reed provide opportunities to improve water quality and reed produces enough biomass to serve as green energy source. Moreover, these wetlands also function as a flood water reservoir and are possibly advantageous for biodiversity. The optimal moment of reed harvesting depends on the goal of the owner. This moment should be chosen wisely, as it may have consequences for reed filter regeneration, biomass production, biodiversity, methane emission and water sanitation efficiency.

Agriculture in a Dynamic World

Through a combination of technological progress and economic policy convergence, globalization has markedly changed the setting for agriculture during the last decade. Through trade and international agreements, global changes increasingly affect development options for both industrialized and developing economies. At national level, continued population growth, expanding economies and urbanization have, especially in densely-populated areas, led to unprecedented competition for land and water resources between agriculture and other uses such as infrastructure, urban, industry and recreation/nature. This challenges the agricultural sector to produce sufficient, more diverse and safe food, fibre products and feedstocks for biofuel in a sustainable manner. This has to be achieved in an increasingly competitive and globalizing economy. Meeting these challenges requires significant changes in the way agriculture and the value chain are organized. Some of the major changes affecting agriculture are:

Climate Change in Dryland West Africa

A short analysis of rainfall trends for West Africa is presented in this chapter. Changes in aridity class and the related drought risk are calculated.