The whole-farm benefits of controlled traffic farming: An Australian appraisal

Controlled traffic farming (CTF) uses a range of technologies to confine traffic-induced compaction to permanently defined tramlines within a farm’s cropping area. CTF concentrates and improves trafficability whilst simultaneously supporting soil structure improvement between tramlines, thereby raising crop yields and offering other advantages such as reduced overlap that saves on crop inputs. This study uses whole-farm modelling to assess the profitability and role of CTF in different farming systems in Australian dryland agriculture. Farming system scenarios with and without the CTF are compared. Stepwise analysis, combined with sensitivity analysis, reveals the characteristics of CTF that most affect its value. Results indicate that the most valuable aspect of the technology is its beneficial impact on the yield and quality of crops grown on soils most subject to compaction. Hence, on farms dominated by these soils and where their faming system emphasizes cropping, CTF forms an especially valuable role. For a typical farm in the study region, employing conservative measures, farm profit increases by around 50% through use of CTF. Hence, CTF represents a remarkably profitable innovation for farming systems, offering input savings and output increases.     

Traditional cropping systems in northwestern Spain (Galicia)

Traditional crops and cropping systems in small-farm agriculture are the result of many years of evolution and selection by the farmers, generally directed towards self-consumption. These systems have been normally based on multiple cropping and intercropping and have been described in areas of Africa, America and Asia, but not generally in Europe. This paper presents the case of Galicia, a region, located in the northwestern corner of Spain, where traditional family land division and other sociological factors have led to a small-farm situation. Surveys conducted in Galicia previous to a thorough investigation of cropping systems show that multiple cropping and intercropping have been the basis of agricultural systems and they are still used extensively. At present, there are three basic crop rotations which differ in the degree of cropping intensity. The three rotations are the annual sequence of corn-Italian ryegrass (intercropped), a 2-year system consisting of corn or potatoes-wheat or rye-turnips and a 2-year system of rye (fallow). A variety of intermediate forms is found that can be considered as having evolved from the three basic rotations. The study also shows how climatic conditions and other factors such as soil fertility, type of farming and labour requirements affect cropping intensity and how the level of intensification influences the total annual dry matter yield per unit of land. These yields can vary from 17–21 t ha⁻¹ in rainfed conditions in the most intensive areas to 2·4 to 3·5 t ha⁻¹ in the rye (fallow) system. At present, the cropping systems of many areas of Galicia are rapidly changing toward a more commercial type of agriculture, because of technical, economic or sociological factors.     

The effect of system innovations on water productivity in subsistence rainfed agricultural systems in semi-arid Tanzania

Rainfed subsistence farming systems in sub-Saharan Africa generally obtain low crop yields as a result of highly erratic rainfall seasons. This paper presents results of research conducted to test the effects of improvements in farming techniques for subsistence rainfed systems. The research was carried out in the Makanya catchment of northern Tanzania where rainfall of less than 600 mm a⁻¹ and spread over two agricultural seasons per year is clearly insufficient to support staple food crops under the present farming systems in the area. The research sought to prove that, with improved efficiency in tillage techniques, grain yields can improve even under the existing challenging hydro-climatic conditions. The research tested farming system innovations (SIs) at four sites located within a spatial distance of 10 km where a combination of runoff diversion (RD), on-site rain water harvesting (WH) and conservation tillage (CT) were compared against the traditional farming methods of hand-hoeing under strict rainfed conditions (Control). For RD, runoff generated from natural storms was directed into infiltration pits dug along the contour with the excavated soil deposited upward of the trenches (fanya juus). The impact of these techniques on maize yields under different SIs was investigated.The results showed that the innovations resulted in increased maize grain yields of up to 4.8 t ha⁻¹ compared against current averages of less than 1 t ha⁻¹. The average productivity of the available water over four seasons was calculated to range between 0.35 and 0.51 kg m⁻³. For the SIs that were tested, the distribution of yields within a cultivated strip showed variations with better yields obtained on the down slope side of the cultivated strip where ponding effects resulted in higher water availability for infiltration and storage. However, due to the large seasonal climate variability, statistical analysis did not show significant differences in the yields (p < 0.05) between different cultivation techniques.The study showed that there is scope to improve grain yields with the little available rainfall through the adoption of techniques which promote water availability and retention within the field. The re-partitioning of water within the field creates mitigation measures against the impact of dry spells and allows alternative cropping in addition to the traditional maize cultivated in the rainfall seasons.     

Determining superior cropping patterns for small farms in a dryland rice environment: Test of a methodology

A methodology for cropping systems research was proposed in 1975. It involved the farmer as an active participant in the research, with test patterns grown on his land under joint farmer-research management. Experience with the use of this methodology in developing a dryland rice-based cropping systems test site in the Philippines is discussed.The potential for increased crop productivity in the major dryland rice-producing region of eastern Batangas province, where the predominant cropping pattern involves dryland rice followed by field corn, was studied by testing the impact of these cropping pattern alternatives: following rice with field crops other than the local Orange flint corn, an intercrop pattern, and a three-crop-per-year pattern. Cooperating farmers applied the alternative patterns on 1000 m² plots adjacent to their rice-corn plots. Some patterns showed yield instability and poor pest resistance. None had any adverse effect on the yield of the next rice crop when compared with the traditional pattern.The research opened several directions in which dryland rice-based patterns may be improved. A shift to an improved corn variety showed promise as an effective means of increasing pattern productivity. Soybeans and sorghum were the outstanding alternative crops to follow rice. Intercrops with corn were productive, but may fit only if labour requirements are not excessive and labour productivity is fairly high.     

Crop–animal interactions in mixed farming systems in Asia

The integration of crop and animal production is well developed in the farming systems of Asia, particularly those in small-scale agriculture. There is marked complementarity in resource use in these systems, with inputs from one sector being supplied to others. Specific examples of the main crop–animal interactions are given for different countries, and reference is made to the results of a number of case studies. These have demonstrated the important contribution that animals make to increased production, income generation, and the improved sustainability of annual and perennial cropping systems.     

Does the adoption of zero tillage reduce greenhouse gas emissions? An assessment for the grains industry in Australia

The Australian Government has recommended that farmers move from cultivation-based dryland farming to reduced or zero tillage systems. The private benefits could include improvements in yields and a decrease in costs while the public benefits could include a reduction in greenhouse gas (GHG) emissions due to a diminution in the use of heavy machinery. The aim of this study is to estimate and compare total on-farm GHG emissions from conventional and zero tillage systems based on selected grain crop rotations in the Darling Downs region of Queensland, Australia. The value chain was identified, including all inputs, and emissions. In addition, studies of soil carbon sequestration and nitrous oxide emissions under the different cropping systems were reviewed.The value chain analysis revealed that the net effect on GHG emissions by switching to zero tillage is positive but relatively small. In addition though, the review of the sequestration studies suggests that there might be soil-based emissions that result from zero tillage that are being under-estimated. Therefore, zero tillage may not necessarily reduce overall GHG emissions. This could have major implication on current carbon credits offered from volunteer carbon markets for converting conventional tillage to reduced tillage system.     

Assessing the impact of the Nitrate Directive on farming systems using a bio-economic modelling chain

Bio-economic models can be used to assess the impact of policy and environmental measures through economic and environmental indicators. Focusing on agricultural systems, farmers’ decisions in terms of cropping systems and the associated crop management at field scale are essential in such studies. The objective of this paper is to present a study using a bio-economic model to assess the impact of the Nitrate Directive in the Midi-Pyrenees region (France) by analyzing, at the farm scale, farm income and three environmental indicators: nitrate leaching, erosion and water consumption. Two scenarios, the 2003 CAP reform (baseline scenario) and the Nitrate Directive (policy scenario), with a 2013 time horizon, were developed and compared for three representative arable farm types in the Midi-Pyrenees region. Different types of data characterizing the biophysical context in the region (soil, climate), the current cropping systems (rotation, crop management) and farm resources (irrigated land, labor) were collected to calibrate and run the models. Results showed that the implementation of the Nitrate Directive may not affect farm income. However, significant modifications to cropping systems and crop allocation to soil types were simulated. Contrary to expectations, nitrogen leaching at the farm scale did not change. Overall water consumption increased and soil erosion decreased due mainly to a modification in cropping patterns and management by soil type. This study provides an example of unanticipated effects of policy and trade-offs between environmental issues.     

Increasing animal productivity on small mixed farms in South Asia: a systems perspective

Smallholder crop–animal systems predominate in south Asia, and most of the projected future demands for ruminant meat and milk are expected to be met from the improved productivity of livestock in these mixed farming systems. Despite their importance in the sub-region, there is a paucity of information on research that incorporates animals interactively with cropping. Livestock research has tended to highlight component technologies, often treating diverse and complex mixed farming operations as a single system. Furthermore, little attention has been paid to social, economic or policy issues. Thus, many of the technological interventions have either failed to become adopted at farm level or their uptake has proved unsustainable. This paper reviews aspects of animal production in South Asia; the trends and forecasts for animal populations and products, constraints to productivity, research opportunities and some key examples of technologies that have failed to achieve their full potential on farm. A systems analysis of small-scale crop–livestock operations is advocated, as a precursor for targeting appropriate interventions at farm level to increase animal productivity and protect the natural resources base.     

Irrigation modernization and water conservation in Spain: The case of Riegos del Alto Aragón

This study analyzes the effects of irrigation modernization on water conservation, using the Riegos del Alto Aragón (RAA) irrigation project (NE Spain, 123354 ha) as a case study. A conceptual approach, based on water accounting and water productivity, has been used. Traditional surface irrigation systems and modern sprinkler systems currently occupy 73% and 27% of the irrigated area, respectively. Virtually all the irrigated area is devoted to field crops. Nowadays, farmers are investing on irrigation modernization by switching from surface to sprinkler irrigation because of the lack of labour and the reduction of net incomes as a consequence of reduction in European subsidies, among other factors. At the RAA project, modern sprinkler systems present higher crop yields and more intense cropping patterns than traditional surface irrigation systems. Crop evapotranspiration and non-beneficial evapotranspiration (mainly wind drift and evaporation loses, WDEL) per unit area are higher in sprinkler irrigated than in surface irrigated areas. Our results indicate that irrigation modernization will increase water depletion and water use. Farmers will achieve higher productivity and better working conditions. Likewise, the expected decreases in RAA irrigation return flows will lead to improvements in the quality of the receiving water bodies. However, water productivity computed over water depletion will not vary with irrigation modernization due to the typical linear relationship between yield and evapotranspiration and to the effect of WDEL on the regional water balance. Future variations in crop and energy prices might change the conclusions on economic productivity.     

An analysis of commercial vegetable farms in relation to sustainability in the uplands of Southeast Asia

Commercial vegetable production systems in the uplands of Southeast Asia are important to supplement the demand for fresh vegetables in lowland Asian cities. A farm survey and soil sampling was done to characterise and identify major factors limiting vegetable productivity in the uplands of the Manupali watershed, Mindanao, the Philippines. Large yield differences were found among the four most common crops: tomato (Lycopersicon esculentum), cabbage (Brassica oleracea var. capitata), potato (Solanum tuberosum), and Chinese cabbage (Brassica pekinensis). The most closely correlated factors with crop yields were: nitrogen application rates for tomato and cabbage; topsoil per cent sand and fungicide usage for potato; and reliance on family labor for Chinese cabbage. Following multivariate data analysis, two vegetable farming systems were identified: the higher external nutrient (HEN) and the lower external nutrient (LEN) systems. To enhance their sustainability, both systems should adopt more appropriate soil conservation practices, cropping sequences, and plant protection techniques. Additionally, the LEN farmers should increase nutrient application, while the HEN farmers would benefit from labor saving technologies, crop diversification, and more judicious fertiliser application.     

Evaluating crop-livestock-based farming systems: A village level study in the dry zone rainfed district of Sri Lanka

In Sri Lanka cropping enterprises interact with livestock production on peasant farms. This analysis of the crop-livestock farming system aims at understanding the existing constraints and interactions between crops and livestock in these farms. The main objective of the study is to describe the crop-livestock integrated farming systems in three rainfed villages in the Moneragala district of Sri Lanka, and to evaluate these systems in terms of maximizing farm incomes from the different crop and livestock components of the systems. A field survey was conducted to collect data from 153 farming families for the Maha season of 1982/83. A linear programming model was formulated to test the hypothesis.The results show that in general the activities for lowland rice, highland rice, sugar cane, labour, farm cash cost, and MVP (compost) are higher in the optimal farm plan than in the actual farm situation. The livestock in the optimal plan is mainly confined to milch cattle. However, with the present high level of manutrition among rural livestock industry emphasis should be placed on the expansion of the rural livestock industry in the study villages. The optimal plan also suggests the use of crop residues as a substitute for compost for farm crops. Hence, in the context of escalating prices of chemical fertilizers, research is required to find the suitability of crop residues and household residues as substitutes for compost. Increases in supplementary irrigation may result in the expansion of the farm area and hence the farm income. Other methods of increasing farm income include: replacing hired labour with non-utilized family labour, increased agricultural research, and extension activity regarding the use of modern inputs by farmers on crops.     

Ex-ante economic analysis of alternative mulch-based management systems for sustainable plantain production in Southeastern Nigeria

Due to rapid loss of soil fertility in traditional cropping systems and subsequent yield decline, plantain fields in Southeastern Nigeria are usually reverted to fallow after three years. This study investigates the potential of mulch-based systems for long term plantain production: alley cropping with Dactyladenia barteri and natural bush, and a cut-and-carry technique with Pennisetum purpureum. Model results simulate yields decline observed under traditional cropping systems due to a decrease in soil fertility. The adoption of mulch-based technologies is conditioned by capital availability. However, when adequate capital is available, mulch-based systems are quite profitable. Under baseline conditions, the alley cropping system with natural bush outperforms the other two improved technologies with a 154% and 72% increase in net returns over continuous and shifting traditional systems, respectively. The traditional system had the worst performance without fertilizer use. A sensitivity analysis shows that the increase in net return due to fertilizer in the alley cropping and traditional systems is at least 25%. This analysis indicates that credit programs that reach small farmers and land reform that gives them secure title are essential to widespread adoption of mulch-based plantain systems.     

Life cycle assessment of Swiss farming systems: I. Integrated and organic farming

Organic farming (OF) is considered a promising solution for reducing environmental burdens related to intensive agricultural management practices. The question arises whether OF really reduces the environmental impacts once lower yields and all the changes in farming methods are taken into consideration. This question is addressed in a comprehensive study of Swiss arable cropping and forage production systems comparing OF to integrated production (IP) systems by means of the life cycle assessment (LCA) method.The LCA study investigated the environmental impacts of two long-term farming system experiments: the DOC experiment comparing bio-dynamic, bio-organic and conventional/integrated farming and the “Burgrain” experiment encompassing integrated intensive, integrated extensive and organic production. All treatments received similar amounts of farmyard manure. The system boundary encompasses the plant production system; storage and application of farmyard manure is included in the system boundary, the animal husbandry is not included. The Swiss Agricultural Life Cycle Assessment method (SALCA) was used to analyse the environmental impacts.In the overall assessment OF was revealed to be either superior or similar to IP in environmental terms. OF has its main strengths in better resource conservation, since the farming system relies mainly on farm-internal resources and limits the input of external auxiliary materials. This results in less fossil and mineral resources being consumed. Moreover the greatly restricted use of pesticides makes it possible to markedly reduce ecotoxicity potentials on the one hand, and to achieve a higher biodiversity potential on the other. This overall positive assessment is not valid for all organic products: some products such as potatoes had higher environmental burdens than their counterparts from IP.The main drawbacks identified for Swiss OF systems are lower yields. As a consequence some production factors are used less efficiently, thus partly negating the advantages of OF. Furthermore, the different manure management strategy leads to relatively high nutrient losses in relation to yield. These two points were shown to be the main priorities for the environmental optimisation of OF systems. The differences between the bio-organic and the bio-dynamic farming systems consisted in a slightly higher input of organic matter, a few applications of mineral fertilisers and copper applications in the former.The eco-efficiency analysis led to the conclusion that the optimisation of OF is mainly output-driven, i.e. that higher yields of good quality should be achieved with the available (limited) resources. On the contrary, optimisation of IP was found to be input-driven; the inputs should be used in a quantity and manner which minimise the environmental burdens per unit produced. The study showed that despite the efforts of recent years, there is still considerable room for the environmental optimisation of Swiss farming systems.     

Water productivity in rainfed systems: overview of challenges and analysis of opportunities in water scarcity prone savannahs

Addressing the Millennium Development Goals on food and poverty over the coming decade puts enormous pressure on the world’s finite freshwater resources. Without water productivity (WP) gains, the additional freshwater in agriculture will amount to 5,600 km³ year⁻¹ in 2050. This is three times the current global irrigation use. This paper focuses on the underlying processes and future opportunities of WP gains in water scarcity prone and poverty stricken savannah regions of the world. The paper studies the consumptive (green) WP dynamics rainfed farming systems, and shows that the often assumed linear relationship between evapotranspiration (ET) and yield (Y) does not translate into constant WP over a wide range of yields. Similarly, crop transpiration (T) and Y show non-linearity under on-farm and low yield conditions. This non-linearity is validated against several on-farm research experiments in semi-arid rainfed farming systems. With integrated soil and water management, focusing on dry spell mitigation and soil fertility can potentially more than double on-farm yields, while simultaneously improve green (ET) WP and productive green (T) WP. Through the adoption of appropriate soil and water management in semi-arid smallholder farming systems, crop yields improve and result in improved livelihoods and WP gains.     

Life cycle assessment of Swiss farming systems: II. Extensive and intensive production

Extensive or low-input farming is considered a way of remedying many problems associated with intensive farming practices. But do extensive farming systems really result in a clear reduction in environmental impacts, especially if their lower productivity is taken into account? This question is studied for Swiss arable cropping and forage production systems in a comprehensive life cycle assessment (LCA) study.Three long-term experiments (DOC experiment comparing bio-dynamic, bio-organic and conventional farming, the “Burgrain” experiment including integrated intensive, integrated extensive and organic systems and the “Oberacker” experiment with conventional ploughing and no-till soil cultivation, are considered in the LCA study. Furthermore, model systems for arable crops and forage production for feeding livestock are investigated by using the Swiss Agricultural Life Cycle Assessment method (SALCA).The analysis covers an overall extensification of cropping systems and forage production on the one hand and a partial extensification of fertiliser use, plant protection and soil cultivation on the other. The overall extensification of an intensively managed system reduced environmental impacts in general, both per area unit and per product unit. In arable cropping systems medium production intensity gave the best results for the environment, and the intensity should not fall below the environmental optimum in order to avoid a deterioration of eco-efficiency. In grassland systems, on the contrary, a combination of both intensively and extensively managed plots was preferable to medium intensity practices on the whole area. The differences in yield, production intensity and environmental impact were much more pronounced in grassland than in arable cropping systems.Partial extensification of a farming system should be conceived in the context of the whole system in order to be successful. For example, the extensification solely of fertiliser use and soil cultivation resulted in a general improvement in the environmental performance of the farming system, whereas a reduction in plant protection intensity by banning certain pesticide categories reduced negative impacts on ecotoxicity and biodiversity only, while increasing other burdens such as global warming, ozone formation, eutrophication and acidification per product unit. The replacement of mineral fertilisers by farmyard manure as a special form of extensification reduced resource use and improved soil quality, while slightly increasing nutrient losses.These results show that a considerable environmental improvement potential exists in Swiss farming systems and that a detailed eco-efficiency analysis could help to target a further reduction in their environmental impacts.     

Application of a simulation model for assessing integration of smallholder shifting cultivation and sheep production in Yucatán, Mexico

Simulation models are effective tools to examine interactions between livestock, cropping systems, households, and natural resources. Our study objective was to use an integrated livestock and crop model to assess the outcomes from selected suites of management decisions observed in smallholder sheep-cropping systems of Yucatán, Mexico. The scenarios contrasted specialized systems versus mixed farming, and evaluated the outcomes of increased crop-livestock integration. Mixed enterprise scenarios involving sheep provided more income than specialized enterprises, and capitalized on a lower price of on-farm maize grain, efficient utilization of surplus labor, and availability of common land. Labor and management income was greatest for the unintegrated and partially integrated crop and livestock scenarios. It was more profitable for producers to sell excess grain and maize stover, and use common land to feed the livestock, suggesting that increased integration does not always result in improved outcomes. The results are consistent with a system not yet pushed to the point where integration is inevitable. For all sets of scenarios, the model structure was able to accommodate subtle management differences to produce appropriate biophysical, labor, and economic outcomes. We conclude there is potential to use similar model development methods to describe other crop-livestock systems, thus providing tools for learning, scenario analysis, and impact assessment.     

Crop–animal systems in Asia: socio-economic benefits and impacts on rural livelihoods

Traditionally, small farmers in Asia have practiced mixed farming. To improve crop and animal productivity, increase farm incomes and maintain the ecological balance, several technology options have been developed through on-station and on-farm research by international organisations and national agricultural research systems. However, a review of the research reveals a paucity of information, particularly in South Asia, on the socio-economic benefits and impacts of these technologies and interventions for poor farming households. This paper presents the few case studies available which document the benefits of new technologies to improve crop–animal systems. Additionally, the paper suggests reasons for the neglect of socio-economics in these studies, and ways to strengthen this dimension.     

The origin and hazard of inputs to crop protection in organic farming systems: are they sustainable?

Sustainability is defined as the ability of a system to ‘continue’. In view of this definition, several aspects of the crop protection activity in organic farming are reviewed according to their ability to ‘continue’. As no absolute measure of sustainability is available, this analysis takes the form of a comparison between organic and conventional crop protection methods. Two elements of crop protection are considered: one being the source of the inputs to crop protection and the other being the environmental hazard of the chemicals used in crop protection. In addition, the sustainability of some of the wider issues related to crop protection methods in organic farming are discussed. It is concluded that organic farming systems are not sustainable in the strictest sense. Considerable amounts of energy are input to organic farming systems, the majority of the compounds utilised in crop protection are derived from non-renewable sources and incur processing and transport costs prior to application. Further, these compounds are not without toxicological hazards to ecology or humans. Despite these problems, it is concluded that organic farming is probably more sustainable than conventional farming in a bio-physical sense. However, an assessment of the overall sustainability of farming systems may depend upon the valuation given by society to their inputs and outputs, and in this sense it is extremely difficult to assess which farming system is most sustainable.