Livestock water productivity in mixed crop–livestock farming systems of the Blue Nile basin: Assessing variability and prospects for improvement

Water scarcity is a major factor limiting food production. Improving Livestock Water Productivity (LWP) is one of the approaches to address those problems. LWP is defined as the ratio of livestock’s beneficial outputs and services to water depleted in their production. Increasing LWP can help achieve more production per unit of water depleted. In this study we assess the spatial variability of LWP in three farming systems (rice-based, millet-based and barley-based) of the Gumera watershed in the highlands of the Blue Nile basin, Ethiopia. We collected data on land use, livestock management and climatic variables using focused group discussions, field observation and secondary data. We estimated the water depleted by evapotranspiration (ET) and beneficial animal products and services and then calculated LWP. Our results suggest that LWP is comparable with crop water productivity at watershed scales. Variability of LWP across farming systems of the Gumera watershed was apparent and this can be explained by farmers’ livelihood strategies and prevailing biophysical conditions. In view of the results there are opportunities to improve LWP: improved feed sourcing, enhancing livestock productivity and multiple livestock use strategies can help make animal production more water productive. Attempts to improve agricultural water productivity, at system scale, must recognize differences among systems and optimize resources use by system components.     

Satisfying future water demands for agriculture

The global demand for water in agriculture will increase over time with increasing population, rising incomes, and changes in dietary preferences. Increasing demands for water by industrial and urban users, and water for the environment will intensify competition. At the same time, water scarcity is increasing in several important agricultural areas.We explore several pathways for ensuring that sufficient food is produced in the future, while also protecting the environment and reducing poverty. We examine four sets of scenarios that vary in their focus on investments in rainfed agriculture and irrigation, and the role of international trade in adjusting for national disparities in water endowments. Rainfed agriculture holds considerable potential but requires adequate mechanisms to reduce inherent risks. Irrigation expansion is warranted in places where water infrastructure is underinvested such as sub-Saharan Africa. In South Asia the scope for improving irrigation performance and water productivity is high. International trade can help alleviate water problems in water-scarce areas, subject to economic and political considerations. We examine also a regionally optimized scenario that combines investments in rainfed and irrigated agriculture with strategic trade decisions. Compared to ‘business as usual’, this scenario reduces the amount of additional water required to meet food demands by 2050 by 80%. Some of that water could be made available for the environment and other sectors. We conclude that there are sufficient land and water resources available to satisfy global food demands during the next 50 years, but only if water is managed more effectively in agriculture.     

Water harvesting and supplemental irrigation for improved water productivity of dry farming systems in West Asia and North Africa

In the dry areas, water, not land, is the most limiting resource for improved agricultural production. Maximizing water productivity, and not yield per unit of land, is therefore a better strategy for dry farming systems. Under such conditions, more efficient water management techniques must be adopted. Supplemental irrigation (SI) is a highly efficient practice with great potential for increasing agricultural production and improving livelihoods in the dry rainfed areas. In the drier environments, most of the rainwater is lost by evaporation; therefore the rainwater productivity is extremely low. Water harvesting can improve agriculture by directing and concentrating rainwater through runoff to the plants and other beneficial uses. It was found that over 50% of lost water can be recovered at a very little cost. However, socioeconomic and environmental benefits of this practice are far more important than increasing agricultural water productivity. This paper highlights the major research findings regarding improving water productivity in the dry rainfed region of West Asia and North Africa. It shows that substantial and sustainable improvements in water productivity can only be achieved through integrated farm resources management. On-farm water-productive techniques if coupled with improved irrigation management options, better crop selection and appropriate cultural practices, improved genetic make-up, and timely socioeconomic interventions will help to achieve this objective. Conventional water management guidelines should be revised to ensure maximum water productivity instead of land productivity.     

Managing water by managing land: Addressing land degradation to improve water productivity and rural livelihoods

The premise of this paper is that the key to effective water resources management is understanding that the water cycle and land management are inextricably linked: that every land use decision is a water use decision. Gains in agricultural water productivity, therefore, will only be obtained alongside improvements in land use management. Expected increases in food demands by 2050 insist that agricultural production - and agricultural water use - must increase. At the same time, competition for water between agricultural and urban sectors will also increase; and the problem is further compounded by land degradation. A global survey suggests that 40% of agricultural land is already degraded to the point that yields are greatly reduced, and a further 9% is degraded to the point that it cannot be reclaimed for productive use by farm level measures. Soil erosion, nutrient depletion and other forms of land degradation reduce water productivity and affect water availability, quality, and storage. Reversing these trends entails tackling the underlying social, economic, political and institutional drivers of unsustainable land use. This paper is based on a review of global experiences, and its recommendations for improving water management by addressing land degradation include focusing on small scale agriculture; investing in rehabilitating degraded land to increase water productivity; and enhancing the multifunctionality of agricultural landscapes. These options can improve water management and water productivity, while also improving the livelihoods of the rural poor.     

Accounting for water use: Terminology and implications for saving water and increasing production

Scarcity and competition for water are matters of increasing concern, as are potential shortages of food. These issues intersect both within the agricultural sector and across all water using sectors. Irrigation is by far the largest user of water in most water-scarce countries, and is under pressure to reduce utilisation (to release water to other sectors, including the environment) and use water more productively to meet demands for food and fibre.The terminology for such intra- and inter-sectoral analysis must be unambiguous across sectors so that interventions and their impacts are properly understood. Such terminology, based on previous work and debate, is set out. Implications for a better understanding of the scope for improved productivity of water in agriculture are traced, and some examples are given using data from recent research submissions, demonstrating the benefits of precise water accounting.     

Improving agricultural water productivity: Between optimism and caution

In its broadest sense, water productivity (WP) is the net return for a unit of water used. Improvement of water productivity aims at producing more food, income, better livelihoods and ecosystem services with less water. There is considerable scope for improving water productivity of crop, livestock and fisheries at field through to basin scale. Practices used to achieve this include water harvesting, supplemental irrigation, deficit irrigation, precision irrigation techniques and soil-water conservation practices. Practices not directly related to water management impact water productivity because of interactive effects such as those derived from improvements in soil fertility, pest and disease control, crop selection or access to better markets.However, there are several reasons to be cautious about the scope and ease of achieving water productivity gains. Crop water productivity is already quite high in highly productive regions, and gains in yield (per unit of land area) do not necessarily translate into gains in water productivity. Reuse of water that takes place within an irrigated area or a basin can compensate for the perceived losses at the field-scale in terms of water quantity, though the water quality is likely to be affected. While crop breeding has played an important role in increasing water productivity in the past, especially by improving the harvest index, such large gains are not easily foreseen in the future. More importantly, enabling conditions for farmers and water managers are not in place to enhance water productivity. Improving water productivity will thus require an understanding of the biophysical as well as the socioeconomic environments crossing scales between field, farm and basin.Priority areas where substantive increases in water productivity are possible include: (i) areas where poverty is high and water productivity is low, (ii) areas of physical water scarcity where competition for water is high, (iii) areas with little water resources development where high returns from a little extra water use can make a big difference, and (iv) areas of water-driven ecosystem degradation, such as falling groundwater tables, and river desiccation. However, achieving these gains will be challenging at least, and will require strategies that consider complex biophysical and socioeconomic factors.     

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.     

An optimization model for zero-excess phosphorus management

Livestock production in the 21st century is moving in the direction of higher animal densities. Accompanying livestock expansion is the challenge of manure handling and utilization. A model for zero-excess phosphorus (ZEP) management has been developed for a dairy-crop operation that is based on multicriteria optimization. ZEP management practices are identified by simultaneously minimizing excess manure phosphorus, feed cost, and cropland requirement. System components include commercial fertilizer application, feed crop production, P storage in the soil profile, surface runoff, procurement of feed supplements, ration formulation, dairy herd structure and dynamics, manure handling, manure storage, and manure spreading. Manure is recycled as a fertilizer nutrient source in crop production. ZEP management practices include a cropping system, nutrient applications, and animal rations which are characterized by low feed cost and maximum use of land resources.     

Exante assessment of dual-purpose sweet potato in the crop–livestock system of western Kenya: A minimum-data approach

Mixed crop–livestock systems have a crucial role to play in meeting the agricultural production challenges of smallholder farmers in sub-Saharan Africa. Sweet potato is seen as a potential remedial crop for these farmers because of its high productivity and low input requirements, while its usefulness for both food and feed (dual-purpose) make it attractive in areas where land availability is declining. In this paper, we develop and apply a ‘minimum-data’ methodology to assess exante the economic viability of adopting dual-purpose sweet potato in Vihiga district, western Kenya. The methodology uses and integrates available socio-economic and bio-physical data on farmers’ land use allocation, production, and input and output use. Spatially heterogeneous characteristics of the current system regarding resources and productivity are analyzed to assess the profitability of substituting dual-purpose sweet potato for other crops currently grown for food and feed. Results indicate that a substantial number of farmers in the study area could benefit economically from adopting dual-purpose sweet potato. Depending on assumptions made, the adoption rate, expressed as the percentage of the total land under adopting farms, is between 55% and 80%. The analysis shows that the adoption rate is likely to vary positively with the average total yield of dual-purpose sweet potato, the harvest index (the ratio between tuber and fodder yields), the price of milk, and the nutritional value of available fodder. This study demonstrates the usefulness of the minimum-data methodology and provides evidence to support the hypothesis that dissemination of the dual-purpose sweet potato could help improve the livelihoods of smallholder farmers operating in mixed crop–livestock systems in east Africa.     

Reducing poverty in sub-Saharan Africa through investments in water and other priorities

Water resources are essential to human development processes and to achieve the Millennium Development Goals that seek, inter alia, to eradicate extreme poverty and hunger, achieve universal literacy, and ensure environmental sustainability. Expanding irrigation is essential to increase agricultural production, which is needed to achieve economic development and attain food security in much of sub-Saharan Africa. Water resources and irrigated agriculture are not developed to their full potential. Currently less than 4% of renewable water resources in Africa are withdrawn for agriculture. Barriers include the lack of financial and human resources to build irrigation and related rural infrastructure and acquire agricultural technology, and inadequate access to markets. This constrains progress towards poverty reduction. We examine the linkages between agricultural water, education, markets and rural poverty through a review of published studies. We argue that, linking agricultural water, education, and market interventions, which are so often implemented separately, would generate more effective poverty reduction and hunger eradication programs. Investments in agricultural water management and complementary rural infrastructure and related policies are the pathways to break the poverty trap in smallholder African agriculture.     

畜禽设施精细养殖中信息感知与环境调控综述

畜禽设施精细养殖是现代畜牧业发展的前沿领域,其核心在于物联网与传统设施养殖的深度融合。近年来,随着传统家庭式养殖模式逐渐退出,中国畜禽养殖场的管理方式已逐步迈向集约化、规模化和设施化,基于养殖动物个体管理和质量保障且满足动物福利要求的畜禽设施精细化养殖已成为畜禽养殖业的最新发展趋势。本文在阐述畜禽设施精细养殖信息感知与环境调控的重要性的基础上,介绍了信息感知与环境调控相关前沿技术,分析了面临的问题与挑战,指出智能传感器技术将成为推动畜禽设施精细养殖进步的底层驱动技术,兼顾畜禽福利和生产性能的动物拟人化智能调控技术和策略等是面临的重要挑战。最后,就中国畜禽设施精细养殖关键技术如何落地提出了相关建议,旨在为中国畜禽设施养殖业的转型升级和可持续发展提供理论参考和技术支撑。     

Exploring changes in the spatial distribution of livestock in China

China's livestock sector is very dynamic as a consequence of increasing demands for animal products. This paper explores the spatial distribution of different groups of livestock in China. Relations between the spatial pattern of livestock distribution and a large number of socio-economic and biophysical variables have been derived by correlation and regression analysis. The thus derived relations are used in a spatially explicit, dynamic simulation model to explore near-future changes in land use and livestock distribution. A baseline scenario and a scenario with improved management of grasslands are evaluated. The results indicate that for both scenarios most increases in livestock numbers are to be expected in China's agricultural region.     

A short-term mechanistic model of forage and livestock in the semi-arid Succulent Karoo: 1. Description of the model and sensitivity analyses

This series of two papers describes a mechanistic model that simulates within years the productivity of vegetation and livestock on the communal semi-arid rangeland of the Succulent Karoo of South Africa. The model enables users to evaluate short-term management decisions on the production of milk and meat and to develop sets of equations and rules for long-term models designed to examine the effects of different strategies on the sustainability of the ecosystem.A soil moisture module partitions daily rainfall between runoff, infiltration and drainage and also simulates the loss of soil moisture by evaporation and transpiration. Forage production by different types of plant is modelled in relation to soil moisture and the present potential for growth. Three factors are assumed to influence the animal’s preference for a specific type of plant or part of a plant: relative abundance, ease of harvesting and digestibility. The model combines three mechanisms of food intake regulation: the rate at which the animal is able to eat forage, physical capacity of the digestive system, and, in young animals, their growth potential. Metabolisable energy intake is partitioned between maintenance, accretion/depletion of body protein and fat, conceptus growth and milk production. Reproductive and survival rates are simulated in relation to predicted liveweight and liveweight changes for the different age classes of livestock.     

家畜饲喂机器人研究进展与发展展望

家畜养殖的生产模式已由粗放型向集约型转变,生产水平不断提高,但较低的劳动生产率和劳动力短缺等问题严重制约中国家畜养殖业的快速发展。利用现代信息和人工智能技术,研发家畜饲喂机器人,包括喂料、推料等机器人,实现数字化、智能化的家畜养殖,提高畜牧养殖生产力是解决上述问题的主要途径。为深入分析机器人技术在家畜养殖中的研究现状,本文收集了国内外家畜机器人研究实例和文献资料,从轨道式喂料机器人、自走式喂料机器人和推料机器人3个方面重点介绍家畜饲喂机器人的研究进展,分析了饲喂机器人的技术特点和实际应用情况,从技术和应用两个方面对国内外饲喂机器人进行了比较,并从战略规划制定、核心技术发展和产业发展趋势三个方面进行展望并提出发展建议,为家畜饲喂机器人在中国的进一步发展和应用提供参考。     

The potential contribution of forage shrubs to economic returns and environmental management in Australian dryland agricultural systems

In face of climate change and other environmental challenges, one strategy for incremental improvement within existing farming systems is the inclusion of perennial forage shrubs. In Australian agricultural systems, this has the potential to deliver multiple benefits: increased whole-farm profitability and improved natural resource management. The profitability of shrubs was investigated using Model of an Integrated Dryland Agricultural System (MIDAS), a bio-economic model of a mixed crop/livestock farming system. The modelling indicated that including forage shrubs had the potential to increase farm profitability by an average of 24% for an optimal 10% of farm area used for shrubs under standard assumptions. The impact of shrubs on whole-farm profit accrues primarily through the provision of a predictable supply of ‘out-of-season’ feed, thereby reducing supplementary feed costs, and through deferment of use of other feed sources on the farm, allowing a higher stocking rate and improved animal production. The benefits for natural resource management and the environment include improved water use through summer-active, deep-rooted plants, and carbon storage. Forage shrubs also allow for the productive use of marginal soils. Finally, we discuss other, less obvious, benefits of shrubs such as potential benefits on livestock health. The principles revealed by the MIDAS modelling have wide application beyond the region, although these need to be adapted on farm and widely disseminated before potential contribution to Australian agriculture can be realized.     

Beyond irrigation efficiency

Parameters for accounting for water balance on irrigation projects have evolved over the past century. Development of the classic term irrigation efficiency is summarized along with recent modifications such as effective irrigation efficiency. The need for terms that describe measurable water balance components of irrigated agriculture is very important, as demands and competition for available renewable water supplies continue to increase with increasing populations. Examples of irrigation efficiency studies conducted during the past few decades are summarized along with related irrigation terminology. Traditional irrigation efficiency terminology has served a valid purpose for nearly a century in assisting engineers to design better irrigation systems and assisting specialists to develop improved irrigation management practices. It still has utility for engineers designing components of irrigation systems. However, newer irrigation-related terminology better describes the performance and productivity of irrigated agriculture. On a river-basin level, improved terminology is needed to adequately describe how well water resources are used within the basin. Brief suggestions for improving irrigation water management are presented.     

Transformation toward agricultural sustainability in New Zealand hill country pastoral landscapes

A multi-stakeholder representative group was established to oversee a project examining the economic and environmental performance of a representative North Island hill country catchment farm at Whatawhata in the western Waikato region of New Zealand. The group included representation from landowners, government agencies and scientists. The group was facilitated through an action research approach incorporating three phases: (1) awareness; (2) forecasting; and (3) implementation. The group identified a set of goals and indicators relevant to achieving a “well managed rural hill catchment” The indicators were used to (a) assess the current state of the catchment farm in relation to the goals; (b) evaluate a range of strategies for improving system performance and (c) evaluate progress toward the goals following land use changes implemented within the catchment farm. Key issues for the group included the availability of data and the setting of appropriate performance benchmarks. From both economic and environmental points of view, the existing farm system was failing to meet the goals set by the management group. Key factors driving these outcomes included the physical and productivity limitations of the soil resource, poor livestock performance and poor water quality. A mixture of research observations, decision support models and expert stakeholder knowledge indicated scope for improving performance through forestry, riparian management, erosion control and livestock intensification options. Based on their evaluation of the forecasting results, the group developed a new land use plan, which depended on significant capital investment in land use and enterprise change. Subsequent monitoring of soils, vegetation, water quality, animal production and financial results over four years showed marked improvement in a number of key performance indicators. In particular, sediment and phosphorus loads and faecal coliform levels decreased rapidly, native forest fragments showed early signs of restoration, lamb and beef productivity increased and the per hectare financial returns of the pastoral component increased. Better matching of land use to land capability has led to short-term improvement in some aspects of the economic and environmental performance of the catchment farm. Progress toward a more sustainable agricultural system was achieved, but at a substantial cost for transformation of the biophysical system, which has implications for the wider sector.     

On-farm labour allocation and irrigation water use: case studies among smallholder systems in arid regions

On-farm measurements and observations of water flow, water costs and irrigation labour inputs at the individual parcel level were made in case studies of smallholder irrigation systems in sub-Saharan Africa and south-eastern Arabia. The systems, in which the water source supplied either single or multiple users, were analysed to address the fundamental issues of labour allocation for on-farm water management as this has important consequences for the success of such systems. Results show that the costs associated with accessing water influenced labour input, because when they were low the farmers tended to increase the irrigation rate and reduce the amount of time they spent distributing the water within their parcels. Conversely when water costs were high, lower flow rates and more time spent in water distribution were observed, and this resulted in more uniform irrigation and higher irrigation efficiency. Also, opportunities and demands for farmers to use their labour for activities other than irrigation can lead them to modify operational or physical aspects of the system so that they can reduce the time they spend distributing water within the parcels, particularly when the water is relatively cheap. Awareness and better understanding of how farmers may allocate their labour for water management will lead to more effective planning, design and management of smallholder irrigation systems.     

基于国外经验的我国畜牧业农产品质量安全管理对策

农产品质量安全管理关乎人民生命健康,是各国长期坚持抓好的一件大事。目前,我国畜牧业快速发展,产销量位居世界第1位,但质量安全管理问题突出。对我国畜牧业农产品质量安全管理的现状进行梳理,总结了国外畜牧业农产品质量安全管理经验,并提出我国畜牧业农产品质量安全管理水平提升的对策。