The Role of Organic Fertilizers in Transition to Sustainable Agriculture in the MENA Region

*Helen Avery*

## **Abstract**

Organic fertilizers can serve as an element of transitions to sustainable low-input agriculture in semi-arid regions of the MENA region. They play a key role in supporting soil biota and soil fertility. Yield improvements, availability and relatively low costs make organic fertilizers an attractive alternative for farmers. In semi-arid regions, important considerations are improved soil quality, which in turn affects soil water retention, while better root development helps crops resist heat and water stress. Organic fertilizers thus support climate adaptation and regional food security. Soil quality is crucial for carbon sequestration, at the same time that increased nutrient retention reduces impacts of agricultural runoff on groundwater and water bodies. Factors that impede the generalised use of organic fertilizers include lack of expertise, subsidy structures, constraints of the wider food and agricultural systems, and difficulties in transitioning from conventional agriculture. Such obstacles are aggravated in countries affected by security issues, financial volatility or restrictions in access to market. Against the background of both general and local constraints, the chapter examines possible pathways to benefit from organic fertilizers, in particular synergies with other sustainable agricultural practices, as well as improved access to expertise.

**Keywords:** organic fertilizers, sustainable agriculture, transition pathways, smallholder farmers, semi-arid regions, low-input agriculture, soil health, soil carbon, GHG emissions, conservation agriculture, water management, climate adaptation and mitigation

### **1. Introduction**

Organic fertilizers are a highly diverse family of products used in agriculture for soil improvement and to provide nutrients. Their characteristics and benefits will depend on their origin and processing, as on how they are used or combined in particular contexts [1–5]. The main common denominator is therefore that organic fertilizers provide a sustainable option to avoid the negative impacts of chemical fertilizers for long term soil fertility [6], decrease vulnerability to climate stress and weather variability, while reducing the impacts of agriculture on the environment [7, 8].

The term 'organic fertilizers' refers to a very wide range of products, as do the terms chemical, inorganic or synthetic fertilizers. It is therefore exceedingly difficult to make sweeping generalisations concerning the respective benefits or characteristics of these types of fertilizers. The task becomes all the more challenging, since

outcomes will depend on numerous factors. These include how the fertilizer matches soil characteristics, crops, climatic and topographical questions, landscape characteristics, but also irrigation and tilling practices, time and manner of application of the fertilizer, as well as details concerning source and manner of producing the fertilizer. Undesirable effects may result from inappropriate fertilizer production processes, and the presence of metals and other contaminants in source materials is a major concern [9, 10]. There are also challenges linked to the overall or local availability of source materials.

Using organic matter to improve soils is not only related to fertility, but also to effects on physical, chemical and biological soil properties, including aeration, permeability, water-holding capacity and nutrient preserving capacity [11]. Benefits will depend on the exact type of organic fertilizer used, as well as on soil characteristics [7, 11]. Organic fertilizers can be used alone, or in combination with other fertilizers. For instance, a study under experimental conditions suggests that under deficit irrigation conditions, a combination of chemical fertilizer with vermicompost produced better results than chemical fertilizer alone [12]. The use of organic fertilizers appears particularly interesting in conditions of stress and weather variability, while a tailored combination with micro-nutrients suitable for crop and soil enhances yields (see e.g., Parmar et al. [13]). However, much of the literature on fertilizers reduces outcome to the question of crop yield rather than resilience, and more specifically short-term gains in crop yield under normal circumstances.

The use of synthetic fertilizers was generalised as part of the so-called green revolution [14, 15], which stood for a vision of modernising agriculture through use of agricultural machinery, synthetic fertilizers, pesticides, and systematic improvement of crop varieties. The ambition was to dramatically increase food production, and thereby alleviate hunger globally, so the focus on short term crop yield is therefore not surprising. The vision of the green revolution was also very much part of an industrial paradigm, with a simplified vision of agriculture as resembling other industrial production processes, with a flow consisting of input and output, controlled process, and output, where success was measured in production units. Today, however, we have come to a realisation that this oversimplification brought with it a very high cost to the environment, human health, as well as a degradation of planetary conditions necessary for food production in the long term. Crop yields remain important, of course, but there are other implications of our choice of agricultural practices that equally need to be considered. While much of agronomical research investigates linear correlations between a small set of isolated factors under relatively stable conditions, Hou et al. [16] argue for the need to consider soil health holistically, dynamically and from an interdisciplinary perspective.

Besides the narrow focus on productivity, the industrial paradigm within which agriculture was placed has tended to favour a comparatively linear and mechanistic understanding, while disregarding the complexity of ecosystems below ground, above ground, and in water bodies. Soil exchanges gases and chemical substances with air, and aerosols from erosion, burning and vegetation affect cloud formation, precipitation and greenhouse effects [17–19]. Also, as farmers have always known, weather is highly unpredictable, and far from the controlled conditions that industrial production supposes. In view of current rapid climate change [20], farmers are facing increasing weather variability, a greater number of extreme events, and a greater extent of uncertainty with respect to future developments [21, 22]. The use of organic fertilizers alone is not sufficient to address these challenges but can, in combination with other sustainable agricultural practices, constitute an important ingredient in farmers' climate adaptation and mitigation strategies.

*The Role of Organic Fertilizers in Transition to Sustainable Agriculture in the MENA Region DOI: http://dx.doi.org/10.5772/intechopen.101411*
