Agricultural Development - Assignment Example

Soil fertility management strategies on the Jos Plateau: the need for integrating 'empirical' and 'scientific' knowledge in agricultural development:A Summary M.W. Pasquini and M.J. Alexander The Geographical Journal, June 2005 171(2): 112-125. An ongoing debate about the integration of farmers' empirical knowledge in agricultural development was sought to be answered by studying soil fertility management strategies in the Jos Plateau of Nigeria. The paper of Pasquini and Alexander (2005) tried to illustrate how farmers collectively can acquire considerable and detailed knowledge, which can be supported by scientific explanations. Through samples of inorganic fertilizers, farmers can make accurate observations of their farming systems and accordingly develop strategies for maintaining and improving output. They argued that scientists should pay closer attention to farmers' knowledge systems when attempting to promote agricultural development. Since time immemorial, the idea that local people could have something to contribute to development is not always considered. Some scholars and scientists often put down local, indigenous knowledge. Often, they dismiss it as 'primitive', 'unscientific' and 'wrong'. Thus, they assigned themselves of 'educating' rural people, using a top-down, transfer-of-technology approach (Okali et al. 1994; Scoones and Thompson 1994a; Sillitoe 2002). Fortunately, Pasquini and Alexander (2005) mentioned that this perspective was challenged with a populist approach that viewed indigenous technical knowledge as a valuable, untapped source, and believed that it had to be 'incorporated' into formal research extension and practices in order to make agricultural development more sustainable. In the late 1980s-early 1990s, a thorough research in the Jos Plateau, Nigeria congruently examined how the knowledge and management of soil fertility by local farmers could be integrated in the development of a viable strategy for the maintenance of soil fertility (Phillips-Howard and Kidd 1991). As a previous site of tin mining since the beginning of the twentieth century, farming systems have been agitated about 320 km2 of cultivable land, much of which was needed for food production, because of the growing population (Alexander and Kidd 2000). In 1949, a series of trials was established to find the best way of restoring the mined land to agriculture, but after three years of trials, the Mines Land Reclamation Unit declared that it was impractical and uneconomic to raise the fertility of the degraded soil to the point that it would be able to sustain traditional arable agriculture (Alexander 1996). Local farmers were unaware of this opinion and continued with their informal reclamation strategy, which proved successful in raising significantly the nutrient status of the soils (Alexander and Kidd 2000). Thus, Phillips-Howard and Kidd (1991) showed that farmers had extensive and detailed knowledge of a variety of traditional (in Hausa: takin gargajiya) and modern (takin zamani) fertilizers, being able to differentiate between them according to their perceived characteristics and usefulness. Inorganic fertilizers are 'modern' fertilizers, whereas various livestock manures and waste ash are classified as traditional fertilizers. In fact, the key to the reclamation strategy was that farmers applied a combination of inorganic fertilizers, different types of animal manure and urban waste ash (Alexander 1996). Also, urban waste ash was regarded as valuable by the farmers, and for this reason one of the conclusions Phillips-Howard and Kidd (1991) came to was that further investigation of the characteristics and supply of this material (tokan bola) (and other unfamiliar fertilizers such as egret manure--kashin balbela) would be worthwhile. Research carried out in the 2000/2001 dry farming season (from September through to May) aimed to provide an appreciation of the role played by urban refuse ash, while highlighting the risks attached to its use. Thus, Pasquini and Alexander (2005) have to identify first the critical characteristics of present soil fertility management practices (i.e. the use of inorganic fertilizers, manure and ash) and acquire an understanding of the rationale behind them in order to prove that their empirical knowledge has a stable basis in complementing the current scientific approach in soil fertility management strategies. Methods In order to understand soil fertility management practices process different techniques were applied, ranging from a questionnaire survey to in-depth, semi-structured interviews about soil fertility management practices, to chemical analyses of fertilizer samples. The research took place on the Jos Plateau in Nigeria, in two locations. The primary location was the Delimi Langalanga farming area, which is located along the Delimi River (the source of irrigation water) on the northern outskirts of the town of Jos. The area has been affected by tin mining, but has been under irrigated cultivation for more than 50 years. The general characteristics of dry season irrigated vegetable farming were explored using a questionnaire survey administered to 52 male farmers in the area (the majority are Hausa and adherents to Islam). The questionnaire also contained questions pertaining to the use of organic and inorganic fertilizers. In addition, 25 male farmers (of varied ages) were interviewed in detail on their soil fertility management practices, and the activities of the area as a whole were monitored closely for the whole dry season farming period from September 2000 through to May 2001. The secondary location of the research was Rayfield, to the southwest of Jos, which has developed agriculturally because of the abandoned, flooded mine workings (ponds) which are used for irrigation. This area has developed particularly in the last 25 years or so. There was also a follow up by interview of 18 male farmers, specifically questioning their use of poultry manure and refuse ash, as the questionnaire had revealed that, unlike Delimi farmers, farmers in this area used large quantities of these inputs. With regards to knowing the viability of fertilizers they use, refuse ash and inorganic fertilizer samples were collected in the field, and transported to the UK for chemical analyses. Fifty-nine ash samples were collected from nine sites in Jos town. The following properties were determined: pH on a saturated paste using a Jenway glass electrode pH meter (Rowell 1994); and total sodium, potassium, calcium, magnesium, iron, manganese, zinc, copper, nickel, cadmium and lead were determined on a nitric acid-extractable microwave-assisted digestion (CEM's MARSX Microwave system) using the Environmental Protection Agency's Method 3051 (CEM 2000), and samples were analysed on a Varian SpectrAA 220FS Atomic Absorption Spectrophotometer. Three samples of NPK 15:15:15 and one each of NPK 20:10:10, NPK 27:13:13 and triple super-phosphate and urea were purchased from market sellers. They were tested for soluble N, P and K (by dissolving the fertilizer in de-ionized water); also for total N and P, using the potassium persulphate digestion method (Johnes and Heathwaite 1992). Additionally, elemental N was also determined on a CHN CE440 elemental analyser. It should be noted that although fertilizer samples were finely ground and mixed thoroughly, it is very difficult to obtain a homogenous sample, particularly because of the small quantities used in their analysis (0.1 g). Findings The interviews of Pasquini and Alexander (2005) in Delimi and Rayfield generated a vast amount of information on soil fertility management practices. As previously reported by Phillips-Howard and Kidd (1991), the farmers have a wide and complex collective body of knowledge about soil fertility management practices. Pasquini and Alexander (2005) have generalized that the basic soil fertility maintenance strategy described by previous authors had not changed substantially. Phillips-Howard and Kidd (1991) reported that the traditional strategy consisted of a mixture of sawdust, ash and cow manure. With the arrival of inorganic fertilizers, farmers incorporated these into their strategy and started using complex combinations of inorganic fertilizers, ash (various types) and manure (various types). These remain the most common approach to soil fertility management. The general consensus is that the best results (in terms of satisfactory crop development and cost-effectiveness) are obtained with a combination of inputs, because every kind of fertilizer plays a specific role within the soil fertility management strategy. Many farmers stressed that the application of organic materials, particularly ash, reduced the crop's requirement for inorganic fertilizer. Pasquini and Alexander (2005) found it striking that farmers who have no knowledge about the constituents of inorganic fertilizer already know about the benefits of the increasingly popular concept that is labelled in the 'scientific' world as integrated plant nutrition (Alexandratos, 1995). In view of their fertilizer use, Pasquini and Alexander (2005) found out that farmers have the tendency to mix different inorganic fertilizers at application. They cited one farmer had a 'recipe' that consisted of a mixture of NPK 15:15:15, urea and super-phosphate in the ratio of 2:1:1. Pasquini and Alexander (2005) theorized that this practice is probably learnt from the experience that for particular soils no single inorganic fertilizer type is adequate. Indeed, as Alexander and Kidd (2000) have observed, the compound inorganic fertilizers marketed on the Plateau are invariably of the wrong formula for the granite-derived soils. What was peculiar was the fact that some farmers made a distinction in the effectiveness between different brands of NPK 15:15:15, including one educated farmer, who knew that they were nominally identical inorganic fertilizers (the results of laboratory analysis of different samples of inorganic fertilizers reported). A related point is that a few farmers complained that inorganic fertilizers seemed to be getting 'weaker'. This could be a manufacturing problem or the first sign of declining soil fertility, or a possible 'dilution'/adulteration of fertilizers by traders, especially when not bought by whole sacks. Pasquini and Alexander (2005) also informed that farmers found the application of ash softened the soil, making it easier to break up and prepare. The improvement of soil structure meant that the growth of a crop's roots through the soil was facilitated. There was no strong consensus as to the situations that required ash application. Some farmers advocated the use of ash in all circumstances, while others explained that it was unnecessary on soft soil. Some farmers applied ash to all crops, other farmers targeted specific crops, and although it was agreed that tomatoes required ash. Thus, Pasquini and Alexander (2005) concluded that empirical knowledge has an important contribution in knowing the appropriate soil fertility management strategies. Although they claimed that this should not be the sole driver of agricultural research. Scientific knowledge clearly has a role to play, as is demonstrated by the farmers' ignorance of the dangers posed by the use of town refuse ash. Ash has been an important component of the reclamation strategy, through its neutralizing properties. As Alexander (1996) has pointed out, unless they are carefully managed, most inorganic fertilizers are acidifying (particularly those commonly available to Jos farmers) so, without the counteracting action of the ash, the soils are likely to acidify quickly, reducing the availability of nutrients, and in the long term causing reduced yields. Thus, it is important to encourage farmers to continue using this amendment, while alerting them to its dangers (a difficult task when farmers are mostly illiterate and the problem is 'invisible'), and helping them to regulate their activities to minimize the health hazards. Pasquini and Alexander (2005) attained their objectives of proving the significance of empirical knowledge to complement scientific findings to improve the soil fertility management practices in Jos. They have proven it by conducting surveys and interviews and combined the what they have collected to come up with scientific basis for these empirical knowledge. In knowing the viability of the combinations of different fertilizers the farmers use, they obtained laboratory results to prove that these could promote the growth of their crops. There is a slight stumbling block on the health risk of using ash because the findings were just based on other studies and not really hospital records to prove that there is indeed a health risk that is involved through using ash. But, their hypotheses were clearly answered and it is deemed that the methods they used could be applicable in other areas where indigenous knowledge of soil fertility management practices is widely used, in order for their knowledge to complement and further enrich the current scientific knowledge on strategies to improve soil fertility management practices. Read More