Policy Brief Hay Mulching Icarda

ECONOMIC ASSESSMENT OF HAY MULCHING UNDER DIFFERENT SALINITY LEVEL IRRIGATION WATERS IN SYRDARYA PROVINCE OF UZBEKISTAN

INTRODUCTION Syrdarya province is one of the regions of Uzbekistan most affected by land degradation (ADB, 2004). Land degradation in the province is mainly manifested by secondary salinization. Among the dominant anthropologic reasons for the rise of salinity are the inefficient operation of drainage and irrigation systems, uneven field leveling, non-observance of agronomic practices in terms of their timing and prescribed techniques, low efficiency of on-farm water use, all of which contribute to a rise in groundwater levels and the subsequent mobilization of salts. Syrdarya is also known for the strong natural risk of land degradation due to its climatic and agro-ecological conditions specified by hot summers and low precipitation, leading to rapid evaporation from soil surfaces and induced salinity.

Insufficiency of fresh water resources is the main constraint for agricultural development in the province, even though it is believed that considerable amounts of underground saline and drainage waters do exist. In this regard, the use of mulching and waters with different salinity level (high, medium, low) has been researched by Uzbek scientists and ICARDA partners under the ADB–funded project on “Bright Spots” (2005-2007) at Ak-Altin experimental station in Syrdarya province. This policy brief draws the conclusions from the results of the socioeconomic feasibility analysis of these experiments and makes the recommendations for farmers, administrators and policy-makers on the strengths and weaknesses of using hay mulching and irrigation with different salinity level waters while cultivating cotton.

PROPOSED TECHNOLOGY

Mulching is a well known soil improvement measure. It is effective in improving soil physical properties by reducing water runoff and increasing water infiltration. It also protects the soil against raindrop impact, preventing soil crusting and contributing to soil organic matter and nutrients. Application of hay mulch to soils can reduce tail water generation at the field level, and thus increase water use efficiency. The advantages of hay mulching are numerous: Firstly, hay mulching allows for greater moisture retention in the soil by

preventing rapid evaporation from the soil surface under high summer temperatures, thus reducing the need for increased irrigation. Secondly, the decomposition of hay increases the fertility of soils adding much needed organic matter and nutrients to the soil. Thirdly, mulching reduces cost associated with weeding and inter-row cultivation. Fourthly, the yields under mulching are higher than without mulching as the moisture is kept in the soil uniformly for 1

a longer period, the upper layer of soil does not become hard. Finally, hay mulching is conducive to the development of different microorganisms and insects communities that ensures the soil remains viable without additional costly cultivation.

Hay mulching technology has also constraints for large scale adoption in the province, as well as in Uzbekistan in general: Firstly, the biggest difficulty for promoting this technology is the hay’s competitive use as animal feed. During informal interviews with farmers it was found out that farmers prefer to give it to animals as feed rather than use it as mulch in growing cotton, mainly because they have more direct and

In addition, irrigating cotton with drainage or mixed waters could contribute to the efficient use of water resources, especially in view of growing shortage of fresh water resources. However, it should be stressed that the main requirement for the sustainability of this practice is the efficient operation of the drainage system.

tangible benefits from livestock production than from cotton cultivation. Secondly, farmers’ awareness of the benefits of hay mulching is also quite limited. Finally, hay for mulching is applied manually, necessitating labor costs, though, we have to also consider that hay mulching saves on labor costs related to inter-row cultivation.

METHODS AND MATERIALS The methodology used for economic evaluation is based on cost benefit analysis

of on-farm enterprise budgets for each treatment under the experiment. The cost

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benefit analysis is a technique for evaluating the total costs of one or more technologies with their total benefits. The data, regarding the total costs including the costs of inputs, as variable costs, and fixed costs such as taxes and depreciation, represent the actually incurred costs during the on-farm trials for the treatments under the project. The total

benefits represent the income from all farm outputs sold at given prices. The difference between the total benefits and total costs is the net benefit from the given technology. The following are the definitions of the main indicators applied in the economic evaluation using cost- benefit method:

a. Marginal Rate of Return (MRR): is the ratio between the change in net benefit or net gross margin (Gross Margin “With” - Gross Margin “Without”) – (Total cost “With” – Total Cost “Without”) and the change in total cost. It shows the returns to the additional investment due to technology adoption. b. Benefit Cost Ratio (B/C): this is the ratio between gross margins and total costs, it is a profitability indicator, values > 1 indicate that the technology is profitable, values < 1 suggest the technology is not profitable.

RESULTS AND DISCUSSION During the experiments in 2005-2007, cotton yields under hay mulching were higher than without mulching, on average, by 7%. Cotton yields were adversely affected by the increase in the level of irrigation water salinity. Although, the mulching costs negatively impacted the profitability of options involving mulching,

the most profitable option among those experimented was the use of mulching with low saline waters (Figure 1). The marginal rate of return of the treatment involving mulching and the use of low saline waters was 110% as compared to no-mulching option with the use of low saline waters.

Benefit-Cost Ratios

Profitability of Altrnative Options 1.22 1.20 1.18 1.16 1.14 1.12 1.10 1.08 1.06 1.04 1.02

Low salinity water

Medium salinity water

High salinity Low salinity water water

No mulching

Medium salinity water

High salinity water

Mulching

Treatments

Figure 1. Profitability of growing cotton under alternative options, Ak-Altyn, Uzbekistan (20052007)

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As a whole, the average marginal rate of return of mulching treatments against those without mulching was 37%. This low level of marginal rate of return of mulching treatments against no-mulching treatments is explained by the low profitability levels under mulching with high salinity waters. In fact, mulching and the use of high salinity waters yielded less net benefits than its nomulching equivalent. Similarly, mulching and use of medium saline waters had the

marginal rate of return of 19% against use of medium saline waters without mulching. Finally, use of high saline waters without mulching generated more marginal returns than with mulching. In this regard, mulching can be feasibly used only in combination with the use of low saline waters. In the other two cases, the level of additional returns from mulching are either not sufficient (medium saline waters), or even negative (high saline waters).

CONCLUSIONS AND RECOMMENDATIONS 1. The analysis demonstrated that hay mulching can be applied with sufficiently high profitability only in combination with low saline waters. Mulching in combination with medium saline waters is slightly more profitable than the use of medium saline waters without mulching, but the level of returns is not sufficiently high to encourage farmers to rapidly adopt this management approach. It is not recommended to use mulching in combination with high saline waters because of negative profitability as compared to use of high saline waters without mulching. 2. Hay mulching contributes to the improvement of soil fertility and leads to increased cotton yields. However, hay’s alternative use as animal feed would be the highest constraint for the adoption of this technology by farmers, since the feeding value of hay used for mulching is an important factor that will make it less profitable to apply hay mulching even when irrigating with low saline waters, since the benefit hay can generate when fed to cattle (milk, meat) can be higher than the additional benefit it brings while cultivating cotton. Authors: NARS:

Sadulla Avezbaev, Abdugani Mukumov Tashkent Irrigation Institute

ICARDA: Aden Aw-Hassan, Alisher Mirzabaev Acknowledgements: German Bezborodov, National Coordinator, Bright Spots Project, Uzbekistan

Contacts: Regional Office of the International Center for Agricultural Research in the Dry Areas (ICARDA) for Central Asia and the Caucasus Email: [email protected]. Website: www.icarda.org/cac

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