Analysis of Intra and Interseasonal Rainfall Variability and Its Effects on Pearl Millet Yield in a Semiarid Agroclimate: Significance of Scattered Fields and Tied Ridges

Establishing food security in sub-Saharan African countries requires a comprehensive and high resolution understanding of the driving factors of crop production. Poor soil and adverse climate conditions are among the major drivers of poor regional crop production. Drought and rainfall variability challenges are not fully being addressed by rainfed producers in semiarid areas. In this study, we analysed the spatiotemporal rainfall variability (STRV) and its effects on pearl millet yield using two seasons of data collected from 38 rain gauge stations scattered randomly in farm plots within a 1500 ha area of semiarid central Tanzania. The STRV effects on pearl millet yield under flat and tied ridge management were analysed. Our results show that seasonal rainfall can vary significantly for neighboring fields at distances of less than 200 m, which impacts yield. The STRV for daily rainfall was found to be more critical than for total seasonal rainfall amounts. Scattering fields can help farmers avoid total harvest loss by obtaining at least some yield from the areas that received adequate rain. The use of tied ridges is recommended to conserve soil moisture and improve yields more than flat cultivation in semiarid areas.Peer Reviewe

Is dry soil planting an adaptation strategy for maize cultivation in semi-arid Tanzania?

Agriculture has the greatest potential to lift the African continent out of poverty and alleviate hunger. Among the countries in sub-Saharan Africa, Tanzania has an abundance of natural resources and major agricultural potential. However, one of the most important constraints facing Tanzania’s agricultural sector is the dependence on unreliable and irregular weather, including rainfall. A strategy to cope with climate uncertainty in semi-arid regions is to proceed with the sowing of the crop before the onset of the rainy season. The advantage is that when the rains start, seeds are already in the soil and can begin immediately the process of germination. The objective of this paper was to assess the effectiveness of dry-soil planting for maize as an adaptation strategy in the context of a changing climate in Dodoma, a semi-arid region in Tanzania. For this assessment, the DSSAT crop model was used in combination with climate scenarios based on representative concentration pathways. A probability of crop failure of more than 80% can be expected when sowing occurs during the planting window (of 21 days) starting on 1st November. The next planting window we assessed, starting on 23rd November (which was still before the onset of rain), presented significantly lower probabilities of crop failure, indicating that sowing before the onset of the rainy season is a suitable adaptation strategy. Results also indicated that, despite not reaching the highest maize grain yields, fields prepared for dry-soil planting still produced adequate yields. The cultivation of several fields using the dry planting method is a strategy farmers can use to cope with low rainfall conditions, since it increases the chances of harvesting at least some of the cultivated fields. We conclude that dry-soil planting is a feasible and valid technique, even in scenarios of climate change, in order to provide acceptable maize yields in semi-arid Tanzania

A framework for a European network for a systematic environmental impact assessment of genetically modified organisms (GMO)

The assessment of the impacts of growing genetically modified (GM) crops remains a major political and scientific challenge in Europe. Concerns have been raised by the evidence of adverse and unexpected environmental effects and differing opinions on the outcomes of environmental risk assessments (ERA). The current regulatory system is hampered by insufficiently developed methods for GM crop safety testing and introduction studies. Improvement to the regulatory system needs to address the lack of well designed GM crop monitoring frameworks, professional and financial conflicts of interest within the ERA research and testing community, weaknesses in consideration of stakeholder interests and specific regional conditions, and the lack of comprehensive assessments that address the environmental and socio economic risk assessment interface. To address these challenges, we propose a European Network for systematic GMO impact assessment (ENSyGMO) with the aim directly to enhance ERA and post-market environmental monitoring (PMEM) of GM crops, to harmonize and ultimately secure the long-term socio-political impact of the ERA process and the PMEM in the EU. These goals would be achieved with a multi-dimensional and multi-sector approach to GM crop impact assessment, targeting the variability and complexity of the EU agro-environment and the relationship with relevant socio-economic factors. Specifically, we propose to develop and apply methodologies for both indicator and field site selection for GM crop ERA and PMEM, embedded in an EU-wide typology of agro-environments. These methodologies should be applied in a pan-European field testing network using GM crops. The design of the field experiments and the sampling methodology at these field sites should follow specific hypotheses on GM crop effects and use state-of-the art sampling, statistics and modelling approaches. To address public concerns and create confidence in the ENSyGMO results, actors with relevant specialist knowledge from various sectors should be involved

Assessment of selected analytical steps undertaken across participatory research actions (Steps (1) Mapping stakeholders across FVC; (2) Inventorying FVC constraints & strategies; (3) Identifying food security criteria; (4) Identifying 3–5 UPS per FVC component; (5) Prioritising UPS in CSS for testing; (6) UPS groups formation; (7) UPS implementation, testing, adaptation; (8) Creation of potential future scenarios; (9) UPS monitoring & impact assessment; (10) UPS out and up-scaling.

<p>Assessment of selected analytical steps undertaken across participatory research actions (Steps (1) Mapping stakeholders across FVC; (2) Inventorying FVC constraints & strategies; (3) Identifying food security criteria; (4) Identifying 3–5 UPS per FVC component; (5) Prioritising UPS in CSS for testing; (6) UPS groups formation; (7) UPS implementation, testing, adaptation; (8) Creation of potential future scenarios; (9) UPS monitoring & impact assessment; (10) UPS out and up-scaling.</p

Pearson correlations of nationality, gender and institutional status across participative steps and different assessment parameters (S1 Table).

<p>Pearson correlations of nationality, gender and institutional status across participative steps and different assessment parameters (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0196790#pone.0196790.s001" target="_blank">S1 Table</a>).</p

Cultural background, gender, and institutional status have an effect on the evaluation of multi-disciplinary participatory action research - Table 2

<p>Cultural background, gender, and institutional status have an effect on the evaluation of multi-disciplinary participatory action research</p> - Table

Intensity levels of participation [23, modified].

<p>Intensity levels of participation [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0196790#pone.0196790.ref023" target="_blank">23</a>, modified].</p

Determining success factors for improving rural livelihood strategies: how can participatory social network mapping help?

International audienceThe integration of upgrading strategies (UPS) as part of the livelihood strategies of small farmers is vital for enhancing their food systems. The success of the UPS implementation largely relies on the interactions among key actors. Understanding the complex social realities of farmers is essential for adapting strategies to the local context. Therefore, the objective of this study is to determine the impact of UPS on the livelihood of participants in two case study areas in Tanzania. We used a mixed-method approach to understand the relations between, roles, and motivations of relevant actors in the participatory implementation of their UPS using the Net-Map tool for social network analysis and focus group discussions. Our results reveal why the implementation of UPS improved people´s livelihoods and allowed us to derive some success factors. Motivations for participating in a UPS group differed to some extent among all UPS groups and all types of actors. Based on our results, we found that UPS allow participants to enhance their social networks within their communities and develop skills that improve their livelihood strategies , resulting in more diverse livelihood outcomes. This research provides a knowledge base for UPS considerations and other participatory actions with local subsistence stakeholders. ARTICLE HISTOR