Posts Tagged ‘Crop residues’

Crop residue allocation to livestock feed, soil improvement and other uses along a productivity gradient in Eastern Africa

Posted by gabrielamartinez on , in Journal Articles

57951Author(s): Duncan, A.J.; Bachewe, F.; Mekonnen, K.; Valbuena, D.; Rachier, G.; Lule, D.; Bahta, M.; Erenstein, O.

Published in: Agriculture, Ecosystems and Environment 2016, vol.228, p.101-110


Crop residues are a key livelihood resource in smallholder mixed crop-livestock systems in Sub-Saharan Africa. With expansion of arable land and resultant decline in grazing resources, crop residues are becoming an increasingly important component of livestock feeds. This demand for livestock feeds has implications for the long-term sustainability of such systems since failure to return biomass to soils has implications for soil quality and the capacity of soils to support long-term productivity. Biomass allocation patterns are likely to vary with overall level of productivity and hence availability. In this study we used a household survey to quantify crop residue allocation patterns across a gradient of productivity in Eastern Africa focusing on two sites in Ethiopia and one in Kenya. We assessed the underlying determinants of crop residue allocation patterns with a view to understanding how productivity increases through intensification will influence biomass allocation in Eastern Africa and how livelihood and natural resource management objectives could be optimized. Results showed that farmers strongly favour allocation of residues to livestock feeding but that allocation to soil increases along the productivity gradient. This reduced feeding to livestock and increased allocation to soil fertility is associated with smaller farm sizes leading to reduced animal traction needs for tillage, increased overall livestock productivity, increased use of inputs and a reduced reliance on farm-based activities in overall livelihood strategies. The implications of these trends are that productivity increases in smallholder systems are likely to reduce pressure on biomass in the long term and that measures that enhance the prospects for farmers to intensify their production systems are likely to increase soil health and sustainability objectives in general. A key conclusion of the work is that intensification of livestock production could reduce crop residue allocation to soils with long term implications for soil productivity.

Bacterial community structure in maize residue amended soil with contrasting management practices

Posted by gabrielamartinez on , in Journal Articles

56851Authors: Ramirez Villanueva, D.A.; Bello López, J.M.; Navarro Noya, Y.E.; Luna Guido, M.; Verhulst, N.; Govaerts, B.; Dendooven, L.

Published in: Applied Soil Ecology, 90: 49–59, 2015.


 

Agricultural practices affect the bacterial community structure in soil. It was hypothesized that agricultural practices would also affect the bacteria involved in the degradation of crop residue. Soil was sampled from four different agricultural practices, i.e. conventional agriculture on the flat or on beds, or conservation agriculture on the flat or on beds. Cultivating crops on the flat is done traditionally, but cultivating crops on beds was introduced so as to avoid water logging during the rainy season and its potential negative effect on yields. Soil from these four treatments was amended in the laboratory with maize residue (Zea mays L.) or its neutral detergent fibre (NDF) fraction, mostly consisting of (hemi) cellulose, and incubated aerobically for 14 days. Maize residue was applied to soil as it is left in the field in conservation agriculture and NDF was added to study which bacteria were favoured by application of (hemi) cellulose. Soil was incubated aerobically while the carbon mineralization and the bacterial population were monitored. On the one hand, the relative abundance of phylotypes belonging to bacterial groups that preferred low nutrient environments was higher in soil with conservation agriculture (e.g. Acidobacteria 17.6%, Planctomycetes 1.7% and Verrucomicrobia 1.5%) compared to conventional practices (Acidobacteria 11.8%, Planctomycetes 0.9% and Verrucomicrobia 0.4%). On the other hand, the relative abundance of phylotypes belonging to bacterial groups that preferred nutrient rich environments, such as Actinobacteria, showed an opposite trend. It was 11.9% in conservation agriculture and 16.2% in conventional practices. The relative abundance of Arthrobacter (Actinobacteria) and Bacillales more than doubled when maize residue was applied to soil compared to the unamended soil and that of Actinomycetales when maize or NDF was applied. Application of organic material reduced the relative abundance of a wide range of bacterial groups, e.g. Acidobacteria, Bacteroidetes, Planctomycetes and Verrucomicrobia. It was found that application of organic material favoured the same bacterial groups that were more abundant in the soil cultivated conventionally while it reduced those that were favoured in conservation agriculture.

Social and income trade-offs of conservation agriculture practices on crop residue use in Mexico’s central highlands

Posted by gabrielamartinez on , in Journal Articles

56872Authors: Beuchelt, T.D.; Camacho Villa, C.T.; Göhring, L.; Hernández Rodríguez, V.M.; Hellin, J.; Sonder, K.; Erenstein, O.

Published in: Agricultural Systems, 134: 61–75, 2015.


 

Conservation agriculture (CA) is promoted worldwide to enhance soil quality, improve farmers’ incomes and increase the resilience of rainfed agro-ecosystems under climate change. A major constraint to the adoption of CA is crop residue management in mixed crop–livestock systems. Farmers have competing uses of crop residues – for soil cover, as fodder or as additional income source – which may explain low CA adoption rates in some countries. This paper describes the social and income trade-offs of different crop residue uses in Mexico at regional, community and household level associated with the introduction of CA. We first spatially analyze the importance of crop residues for fodder supply and identify municipalities with fodder surplus at national and regional level. Second, we assess the likely social trade-offs and implications for farming communities of changing a typical farm households’ residue allocation. Third, we identify the effects of crop residue uses on gross margins of maize and barley and assess the economic optimal crop residue allocation at the farm level with short planning horizons.
The paper focuses on maize and barley producers in the central Mexican highlands and combines primary quantitative and qualitative data with secondary data.
Analysis shows that at a national level, Mexico has a fodder surplus while the central highlands have a deficit. Crop residues are a major fodder source in Mexico, contributing up to 40% of fodder availability.
Crop residues are also an important income source which implies costs for introducing CA in the central highlands. Our analysis indicates that retaining crop residues in-situ influences gross margins and that retention of roughly 45% of residues maximizes gross margins in situations where opportunity costs for the use of crop residues exist. Partial residue retention, sequential introduction and combination of technologies may facilitate CA uptake but CA remains a challenge for resource-poor farmers given their limited liquidity, risky production environment and difficulty to forego current income for future benefits.
More interdisciplinary research is needed around economic optimal residue retention levels under different farming and production conditions, to identify the ecological needed minimum cover of crop residues for CA and to develop alternative low-cost sustainable technologies with short-term benefits.

Economic trade-offs of biomass use in crop-livestock systems : exploring more sustainable options in semi-arid Zimbabwe

Posted by gabrielamartinez on , in Journal Articles

56873Authors: Homann-Kee Tui, S.; Valbuena, D.; Masikati, P.; Descheemaeker, K.; Nyamangara, J.; Claessens, L.; Erenstein, O.; Rooyen, A.; Nkomboni, D.

Published in: Agricultural Systems , 134: 48–60, 2015.


 

In complex mixed crop-livestock systems with limited resources and biomass scarcity, crop residues play an important but increasingly contested role. This paper focuses on farming systems in the semi-arid areas of Zimbabwe, where biomass production is limited and farmers integrate crop and livestock activities.
Conservation Agriculture (CA) is promoted to intensify crop production, emphasizing the retention of surface mulch with crop residues (CR). This paper quantifies the associated potential economic tradeoffs and profitability of using residues for soil amendment or as livestock feed, and explores alternative biomass production options. We draw on household surveys, stakeholder feedback, crop, livestock and economic modeling tools. We use the Trade-Off Analysis Model for Multi Dimensional Impact Assessment (TOA-MD) to compare different CR use scenarios at community level and for different farm types: particularly the current base system (cattle grazing of maize residues) and sustainable intensification alternatives based on a CA option (mulching using maize residues ± inorganic fertilizer) and a maize–mucuna (Mucuna pruriens) rotation. Our results indicate that a maize–mucuna rotation can reduce trade-offs between CR uses for feed and mulch, providing locally available organic soil enhancement, supplementary feed and a potential source of income. Conservation Agriculture without fertilizer application and at non-subsidized fertilizer prices is not financially viable; whereas with subsidized fertilizer it can benefit half the farm population. The poverty effects of all considered alternative biomass options are however limited; they do not raise income sufficiently to lift farmers out of poverty. Further research is needed to establish the competitiveness of alternative biomass enhancing technologies and the socio-economic processes that can facilitate sustainable intensification of mixed crop-livestock systems, particularly in semi-arid environments.

Determinants of maize stover utilization as feed, fuel and soil amendment in mixed crop-livestock systems, Ethiopia

Posted by Carelia Juarez on , in Journal Articles

Published in Agricultural Systems, 2014.

Jaleta Debello Moti; Kassie, M.; Erenstein, O.

Crop residues have several uses in smallholder mixed crop-livestock systems. This paper examines determinants of households’ maize stover use as livestock feed, fuel and soil amendment in maize-based systems in Ethiopia. In these systems maize stover is primarily used as feed (56% of biomass) and fuel (31%), with the feed use share negatively associated with maize production potential. We develop a Seemingly Unrelated Regression model to capture the interdependence of crop residue uses. Results show extension training on crop residue retention in the field results in more residue use for soil amendment and less for feed. Farmers with more livestock tend to use more residues for feed and less for soil mulch. Cropping pattern, farm size, agro-ecology and crop residue production also influence crop residue utilization. Conservation agriculture interventions have implications for crop residue use and need to consider access to information, cropping patterns, resources endowments and other socio-economic factors in their development and targeting.

Rastrojos: manejo, uso y mercado en el Centro y Sur de Mexico

Posted by Carelia Juarez on , in CIMMYT Publications

Rastrojos: manejo, uso y mercado en el Centro y Sur de Mexico2013Velez Izquierdo, A.Guevara Hernandez, F.Gomez Castro, H.Ovando Cruz, J.Hellin, J.Espinosa Garcia, J.A.Sonder, K.Rodriguez Larramendi, L.A.Reyes Muro, L.Fonseca Flores, M.Ocaña Grajales, M.Borja Bravo, M.Pinto Ruiz, R.Camacho, C.Beuchelt, T.D.Hernandez Rodriguez, M. 1. ed.Aguascalientes, Ags. (Mexico)INIFAP / SAGARPA / CIMMYT / Centro de Investigacion Regional Norte Centro vii, 242 p. Series: Libro Tecnico. No. 7 

99007Los residuos de cosecha, también conocidos como rastrojos, desempeñan un papel preponderante en los sistemas agrícolas y pecuarios, y han sido estudiados desde diferentes perspectivas temáticas y metodológicas a nivel mundial.

Understanding the impact and adoption of conservation agriculture in Africa: A multi-scale analysis

Posted by Carelia Juarez on , in Journal Articles

Published in  Agriculture, Ecosystems and  Environment, 2013

Corbeels, M.; Graaff, Jan de; Ndah, T.H.; Penot, E.; Baudron, F.; Naudin, K.; Andrieu, N.; Chirat, G.; Schuler, J.; Nyagumbo, I.; Rusinamhodzi, L.;Traore, K.; Mzoba, H.D.; Adolwa, I.S.

Conservation agriculture (CA) is increasingly promoted in Africa as an alternative for coping with the need to increase food production on the basis of more sustainable farming practices. Success with adopting CA on farms in Africa has been limited, despite more than two decades of research and development investments. Through analyzing past and on-going CA experiences in a set of case studies, this paper seeks to better understand the reasons for the limited adoption of CA and to assess where, when and for whom CA works best. CA is analyzed and understood within a framework that distinguishes the following scales of analysis: field, farm, village and region. CA has a potential to increase crop yields in the fields, especially under conditions of erratic rainfall and over the long-term as a result of a gradual increase of overall soil quality. The impact on farm income with the practice of CA on some fields of the farm is far less evident, and depends on the type of farm. The lack of an immediate increase in farm income with CA explains in many cases the non-adoption of CA. Smallholders have often short-term time horizons: future benefits do not adequately outweigh their immediate needs. Another key factor that explains the limited CA adoption in mixed crop-livestock farming systems is the fact that crop harvest residues are preferably used as fodder for livestock, preventing their use as soil cover. Finally, in most case studies good markets for purchase of inputs and sale of produce – a key prerequisite condition for adoption of new technologies – were lacking. The case studies show clear evidence for the need to target end users (not all farmers are potential end user of CA) and adapt CA systems to the local circumstances of the farmers, considering in particular the farmer’s investment capacity in the practice of CA and the compatibility of CA with his/her production objectives and existing farming activities. The identification of situations where, when and for whom CA works will help future development agents to better target their investments with CA.

Effects of conservation agriculture on runoff, soil loss and crop yield under rainfed conditions in Tigray, Northern Ethiopia

Posted by on , in Journal Articles

Published in Soil Use and Management 27(3): 404-414, 2011

Effects of conservation agriculture on runoff, soil loss and crop yield under rainfed conditions in Tigray, Northern Ethiopia

Tesfay Araya, W. M. Cornelis, J. Nyssen, B. Govaerts, H. Bauer, Tewodros Gebreegziabher, Tigist Oicha, D. Raes, K. D. Sayre, Mitiku Haile and J. Deckers

The aim of conservation agriculture (CA) is to improve soil quality and crop yield whilst reducing runoff and topsoil erosion. An experiment was carried out in a rainfed field using a permanent raised bed planting system for 3 yr (2005–2007) in Adigudem, northern Ethiopia in order to evaluate the effect of CA on runoff, soil loss and crop yield. CA practices were introduced in fields with Vertisols in a randomized complete block design on permanent 5 × 19 m plots. Three treatments were evaluated: (1) conventional tillage (CT) with a minimum of three tillage operations and removal of crop residues, (2) terwah (TER) that was similar to CT except that contour furrows were included at 1.5 m intervals, and (3) derdero+ (DER+), which consists of permanent raised beds with a furrow and bed system, retention of 30% of standing crop residues and zero tillage on the top of the bed. All ploughing as well as the maintenance of the furrows of the permanent raised beds was done using a local ard plough called maresha. Results from monitoring over 3 yr showed that soil loss and runoff were significantly higher (< 0.05) in CT followed by TER and DER+. Average soil losses of 5.2, 20.1 and 24.2 t/ha were recorded from DER+, TER and CT, respectively. Runoff was 46.3, 76.3 and 98.1 mm from DER+, TER and CT, respectively. Grain yield was significantly lower (< 0.05) in DER+ under teff in 2006, probably due to the high sensitivity of teff to weeds. The yield of wheat in 2007 was significantly higher in DER+ followed by TER. The terwah system is recommended as a first measure for wider adoption to reduce runoff and soil loss and to increase crop yield. The long-term goal is to achieve a derdero+ system, i.e. a permanent raised bed planting system along with the application of crop residues.

Soil water content, maize yield and its stability as affected by tillage and crop residue management in rainfed semi-arid highlands

Posted by on , in Journal Articles

Published in Plant and Soil, 344(1-2):73-85, 2011

Soil water content, maize yield and its stability as affected by tillage and crop residue management in rainfed semi-arid highlands

Nele Verhulst, Victoria Nelissen, Niels Jespers, Heleen Haven, Ken D. Sayre, Dirk Raes, Jozef Deckers and Bram Govaerts

Rainfed crop management systems need to be optimized to provide more resilient options to cope with projected climatic scenarios forecasting a decrease in mean precipitation and more frequent extreme drought periods in Mexico. Soil water content (0–60 cm) was measured during three crop cycles in maize plots with different agronomic management practices in a long-term rainfed experiment (established in 1991) in the highlands of Mexico. Maize yields of 1997–2009 were reported. Crop management practices varied in (1) tillage (conventional [CT] vs. zero tillage [ZT]) and (2) residue management (full or partial retention and removal). ZT with residue retention had higher soil water content than management practices involving CT and ZT with residue removal which provided a buffer for drought periods during the growing seasons. In 2009, a cycle with a prolonged drought during vegetative growth, this resulted in yield differences of up to 4.7 Mg ha−1 between ZT with (partial) residue retention and the other practices. Averaged over 1997–2009, these practices had a yield advantage of approximately 1.5 Mg ha−1 over practices involving CT and ZT with residue removal. ZT with (partial) residue retention used rainfall more efficiently and resulted in a more resilient agronomic system than practices involving either CT or ZT with residue removal.