促进粮食作物适度规模化生产的关键问题及解决方法

通过对我国农作物规模化种植现状的分析和思考,结合我国农业现代化发展趋势,发现我国在发展粮食作物适度规模化种植中存在的问题。通过分析土地流转与集中、新型农业经营主体的建设与管理以及政府扶持政策等问题,结合我国基本国情,提出促进粮食作物适度规模化生产经营的解决方法与建议,以保障规模化生产经营的可持续健康发展。      

有机肥对我国盐碱地土壤改良及作物生长影响的研究进展

盐碱地是我国重要的后备耕地战略资源，盐碱地的绿色改良与合理有效利用对于保障我国粮食安全具有重要意义。近年来，有机肥在农业生产中的应用越来越广泛，有机肥改良盐碱地的研究也备受关注。然而有机肥对盐碱地的改良效果受盐碱类型、原料种类、施用方式（单施、配施）、施用量、作物种类以及施用年限等因素的影响，不同研究得出的结论具有差异且缺乏系统总结，限制了有机肥在盐碱地中的发展与应用。基于此，本文综述了有机肥对我国盐碱地土壤理化性质、土壤微生物、作物产量及品质等方面影响的研究成果，从环境友好角度分析有机肥改良盐碱地的效果及存在的问题，并结合我国国情提出有机肥在盐碱地中进一步研究的方向，以期为我国盐碱地绿色生态治理提供参考。     

我国热带作物机械的发展现状与对策

热带作物机械化是农业机械化和农业工程学科的一个主要组成部分,发展热带作物机械化对全国热区农垦乃至新农村建设都具有现实意义。为此,依据历年统计数据,阐述了热带作物机械的发展现状及存在的问题,并结合当前热带作物机械行业发展形势,提出针对热带作物机械发展的建议与对策。     

突破“瓶颈”制约又好又快发展现代农业

黑龙江省农业已进入新的历史发展机遇期,年粮食生产能力已稳定在4000万t左右,在全国粮食安全格局中的作用更加突出,成为不可替代的全国商品粮生产战略基地。为此,回顾了黑龙江省农业的发展现状和历史经验,重点分析了制约农业发展的"瓶颈"问题,即农村土地经营规模问题、农业基础设施落后问题、农机服务体系建设滞后问题以及农业机械化发展不平衡等问题,指出发展现代农业的唯一出路是全面落实科学发展观、深化农村综合改革、调整农业生产关系和进一步解放农业生产力。     

An evaluation of the structure and function of tropical homegardens

Homegardens represent land use systems involving deliberate management of multipurpose trees and shrubs in intimate association with annual and perennial agricultural crops and, invariably, livestock, within the compounds of individual houses, the whole crop-tree-animal unit being intensively managed by family labour. Known by different names in various places, these agroforestry systems are common in all ecological regions of the tropics and subtropics, especially in humid lowlands with high population density.An analysis of the structural and functional aspects of ten selected homegarden systems from different ecological and geographical regions shows that the average size of the homegarden units is less than 0·5 ha; yet they are composed of a large number of woody and herbaceous species, carefully structured to form 3–5 vertical canopy strata, with each component having a specific place, as well as function.Food production is the primary function of most homegardens, the vast majority of them being subsistence production systems. While there is a remarkable similarity among the different homegardens with respect to the type and nature of the herbaceous crops, the nature of woody perennials varies, depending on environmental and ecological factors. In general, most woody components produce fruits or other types of food in addition to other outputs such as fuelwood, timber, etc. These various food products provide a substantial proportion of nutritive and energy requirements of the local diet. Moreover, the species diversity and varying production cycles of the different components ensure continuous production throughout the year from the homegarden unit.Little or no research has been done to improve homegarden systems. Structural complexity, species diversity, multiple output nature, tremendous variability from farm to farm, etc., are some of the main characteristics that make the homegardens extremely difficult models to work with according to the currently available research procedures.     

Water management and crop production for food security in China: A review

Food security is a high priority issue on the Chinese political agenda. China’s food security is challenged by several anthropogenic, sociopolitical and policy factors, including: population growth; urbanization and industrialization; land use changes and water scarcity; income growth and nutritional transition; and turbulence in global energy and food markets. Sustained growth in agricultural productivity and stable relations with global food suppliers are the twin anchors of food security. Shortfalls in domestic food production can take their toll on international food markets. Turbulence in global energy markets can affect food prices and supply costs, affecting food security and poverty. Policy safeguards are needed to shield food supply against such forces. China must make unremitting policy responses to address the loss of its fertile land for true progress towards the goal of national food security, by investing in infrastructure such as irrigation, drainage, storage, transport, and agricultural research and institutional reforms such as tenure security and land market liberalization. The links between water and other development-related sectors such as population, energy, food, and environment, and the interactions among them require reckoning, as they together will determine future food security and poverty reduction in China. Climate change is creating a new level of uncertainty in water governance, requiring accelerated research to avoid water-related stresses.     

How much land is needed for global food production under scenarios of dietary changes and livestock productivity increases in 2030?

Growing global population figures and per-capita incomes imply an increase in food demand and pressure to expand agricultural land. Agricultural expansion into natural ecosystems affects biodiversity and leads to substantial carbon dioxide emissions.Considerable attention has been paid to prospects for increasing food availability, and limiting agricultural expansion, through higher yields on cropland. In contrast, prospects for efficiency improvements in the entire food-chain and dietary changes toward less land-demanding food have not been explored as extensively. In this study, we present model-based scenarios of global agricultural land use in 2030, as a basis for investigating the potential for land-minimized growth of world food supply through: (i) faster growth in feed-to-food efficiency in animal food production; (ii) decreased food wastage; and (iii) dietary changes in favor of vegetable food and less land-demanding meat. The scenarios are based in part on projections of global food agriculture for 2030 by the Food and Agriculture Organization of the United Nations, FAO. The scenario calculations were carried out by means of a physical model of the global food and agriculture system that calculates the land area and crops/pasture production necessary to provide for a given level of food consumption.In the reference scenario - developed to represent the FAO projections - global agricultural area expands from the current 5.1 billion ha to 5.4 billion ha in 2030. In the faster-yet-feasible livestock productivity growth scenario, global agricultural land use decreases to 4.8 billion ha. In a third scenario, combining the higher productivity growth with a substitution of pork and/or poultry for 20% of ruminant meat, land use drops further, to 4.4 billion ha. In a fourth scenario, applied mainly to high-income regions, that assumes a minor transition towards vegetarian food (25% decrease in meat consumption) and a somewhat lower food wastage rate, land use in these regions decreases further, by about 15%.     

Research needs and methods for decentralised economic planning

International debates on food and agricultural policy increasingly endorse the principles of the free market and stress the responsibilities of national governments for active policies to manage development, to achieve food security and to safeguard the environment. This paper argues that consequently policy-oriented research needs to establish databases and develop models, in which both rural and urban households figure prominently and in a properly geo-referenced manner. This will enable the policy analyst to design policies and to monitor their effect on a regional basis. The paper emphasises that policy-oriented research should provide a nationwide perspective, because in relation to sustainability, as far as environmental economics is concerned, virtually all theory and theory-based policy guidelines have been formulated for national economies in their totality. With respect to the representation of agricultural production itself, we discuss a class of spatial estimation techniques that can deal with missing data and account for qualitative observations, and that can make full use of spatially explicit information on crop yield potentials as generated by agro-ecological models.     

Simulating the effects of tax exemptions on fertiliser use in Benin by linking biophysical and economic models

The sluggish increase in the area productivity of staple crops is a major factor causing increased dependence of African countries on food imports. The increased use of mineral fertiliser may dramatically improve the food balance of many countries and result in lower food prices, higher food supply and consumption, and improved food security and nutritional status. In Benin, West Africa, political measures to improve farmers’ access to fertiliser are biased in favour of cotton production. This article simulates the impact of universal tax exemptions for fertiliser use on crop yields, food balances, and the use of land resources for the most important staple crops in Benin using a crop growth model and an agricultural sector model. The simulation results indicate that tax exemptions on fertiliser use could have positive effects on physical productivity and would increase food security until 2025 as compared to a baseline scenario. At the same time, the pressure on land resources would not be aggravated, so that better access to fertiliser may help to curb excessive cropland expansion in Benin.     

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.     

中俄薯类作物生产技术效率比较研究

研究中俄两国之间农作物生产技术效率,对于比较两国农业生产效率优势,促进两国之间的农业生产合作具有重要意义。采用三阶段DEA方法,选取中国31个省份和俄罗斯79个州的薯类2017年的生产数据,在清除土地质量因素影响下,对中俄两国的薯类作物生产技术效率进行评价。研究发现:(1)一阶段DEA测试结果显示,俄罗斯薯类作物生产技术效率、纯技术效率和规模效率都高于中国,表明俄罗斯薯类作物的生产技术和管理水平高于中国,且中俄两国的薯类生产均为规模报酬递增。(2)在去除各个地区的土地质量因素影响后,情况发生较大变化,中国薯类作物的技术效率、规模效率显著地高于俄罗斯,表明中国的薯类作物的生产技术明显高于俄罗斯,而纯技术效率俄罗斯略高一些。同时两国薯类作物生产的规模报酬递增趋势更为明显。研究结论对于分析中俄两国的农业生产技术、生产管理水平,促进中俄农业合作具有一定的参考价值。     

Exploratory study on the land area required for global food supply and the potential global production of bioenergy

The areas of agricultural land on this globe that in the future possibly are available for biomass production for energy use and the potential global production of biomass were calculated. These available land areas increased when the global potential for food production (dependent on agricultural system and available land areas for agriculture) became higher in comparison to the global food requirement (dependent on population growth and mean consumption pattern). This study shows that 55% of the present agricultural land area at the global scale is needed for food production in the future (i.e. year 2050), if a high external input system of agriculture is applied. The remaining 45% can be used for other purposes, such as biomass production. If all potentially suitable land areas would be cultivated, the global potential for biomass production becomes about two times as large. If a low external input system is applied at the global scale for food production, however, no land area is available for biomass production.     

Adapting to climate change: Agricultural system and household impacts in East Africa

The East African region exhibits considerable climatic and topographic variability. Much spatial and temporal variation in the response of different crops to climate change can thus be anticipated. In previous work we showed that a large part of this variation can be explained in terms of temperature and, to a lesser extent, water effects. Here, we summarise simulated yield response in two crops that are widely grown in the region, maize and beans, and investigate how the impacts of climate change might be addressed at two levels: the agricultural system and the household. Regionally, there are substantial between-country and within-system differences in maize and bean production responses projected to 2050. The arid-semiarid mixed crop-livestock systems are projected to see reductions in maize and bean production throughout most of the region to 2050. Yields of these crops in the tropical highland mixed systems are projected to increase, sometimes substantially. The humid-subhumid mixed systems show more varied yield responses through time and across space. Some within-country shifts in cropping away from the arid-semiarid systems to cooler, higher-elevation locations may be possible, but increased regional trade should be able to overcome the country-level production deficits in maize and beans caused by climate change to 2050, all other things being equal. For some places in the tropical highlands, maize and bean yield increases could have beneficial effects on household food security and income levels. In the other mixed systems, moderate yield losses can be expected to be offset by crop breeding and agronomic approaches in the coming decades, while more severe yield losses may necessitate changes in crop types, movement to more livestock-orientated production, or abandonment of cropping altogether. These production responses are indicative only, and their effects will be under-estimated because the methods used here have not accounted for increasing weather variability in the future or changes in the distribution and impacts of biotic and other abiotic stresses. These system-level shifts will take place in a context characterised by high population growth rates; the demand for food is projected to nearly triple by the middle of this century. Systems will have to intensify substantially in response, particularly in the better-endowed mixed systems in the region. For the more marginal areas, the variability in yield response, and the variability in households’ ability to adapt, suggest that, even given the limitations of this analysis, adaptation options need to be assessed at the level of the household and the local community, if research for development is to meet its poverty alleviation and food security targets in the face of global change.     

农业机械化水平对中国粮食生产技术效率的空间溢出效应研究——基于农机跨区作业视角

提升农业机械化水平是落实国家“藏粮于技”战略中的重要一环，利用1998—2020年中国31个省(市、区)的面板数据，采用空间杜宾模型，研究农业机械化水平对粮食生产技术效率的直接影响和空间溢出效应。研究发现：第一，农业机械化水平对粮食生产技术效率具有显著的空间溢出效应，在其他影响因素不变的情况下，其他地区粮食生产技术效率加权值每提升1%，本地粮食生产技术效率提升约0.579%；第二，从不同农机类型来看，农业机械化水平对粮食生产技术效率的空间溢出效应主要通过大中型农机实现，影响系数为0.252；第三，农业机械化水平对粮食生产机械效率的空间溢出效应存在于不同经纬度之间，在水稻跨区作业省份中，农业机械化水平对粮食生产技术效率的空间溢出效应为0.027。因此，提出通过进一步优化农机跨区作业机型、改进粮食品种、提升田间管理技术等方式扩大不同地区粮食作物的种植、生长和收获时间差，为农机跨区作业创造条件，实现资源效益最大化。     

基于土地流转的家庭农场经营规模与经济效益分析

在小麦玉米轮作的前提下,分析了黄淮海地区小麦玉米轮作机械化作业模式;以10年承包年限为例,计算了购买农机具10年内作业总费用,将其与租用农机具作业费用进行比较,找到了自购农机具费用低于租赁农机具作业的最低土地面积。在自购农机具的基础上,以40hm^2土地为例计算开始盈利年限。结果表明：在一定范围内,只有通过提高粮食作物的生产规模和承包年限,才能通过土地流转切实提高农民的收入。     

The role of ‘virtual water’ in efforts to achieve food security and other national goals,with an example from Egypt

The term ‘virtual water’ has been used previously to describe the volume of water embodied in food crops that are traded internationally. This paper describes the economic dimension of the ‘virtual water’ concept as an application of comparative advantage, with particular emphasis on water as the key factor of production. The paper also extends the discussion of ‘virtual water’ by describing a nation’s goals regarding food security within a broader framework that includes other objectives such as providing national security, promoting economic growth, and improving the quality of life for citizens. The analysis suggests that land, labor, and capital must also be considered when evaluating a nation’s production and trade opportunities. In countries where one or more of those resources is limiting, focus on ‘virtual water’ alone will not be sufficient to determine optimal policies for maximizing the social net benefits from limited water resources. In countries where labor is relatively abundant, public policies that promote labor-intensive crop production and processing activities may be desirable. The role of ‘virtual water’ within a broader policy framework is demonstrated using crop production and international trade data from Egypt, where substantial amounts of ‘virtual water’ and ‘virtual land’ are embodied in wheat and maize imports. Policies that promote increased exports of labor-intensive crops will improve rural incomes and enhance food security.     

国内农用泵种类及发展趋势

泵是把原动机的机械能转换成所抽液体能量的机械,广泛应用于国民生产各个领域。在农业生产中,泵的应用覆盖了灌溉、植保、施肥等作业领域,为保障国家粮食安全发挥了重要作用。介绍了各类农业用泵的发展历程、技术特点、研究方向,总结了农业用泵向提高可靠性、提高寿命、提高效率、拓展规格、集成智能控制系统、轻型化和社会化生产方面发展的趋势。      

Development of a system to produce maps of agricultural profit on a continental scale: An example for Australia

Policy makers in the agricultural sector are confronted with challenges which might drive land use change and ultimately agricultural profitability to a substantial degree. The challenges include questions around climate variability, demographic changes, use of land for bio-fuel production and ensuring an increase in food production. As profitability triggers many agri-business decisions, knowledge about the existing socio-economic landscape and the economic profile of a region as well as potential impacts on profits provides useful contextual information when agricultural policies are designed. Given the upcoming challenges and their associated uncertainties, it is important to ensure that a map of agricultural profit can be reproduced in a scenario and simulation setting which will allow exploring uncertainties around the impacts on agricultural profits as well. There is however currently no flexible system in operation which allows for a consistent update of a map of agricultural profits in Australia or elsewhere. This paper describes a process that has been developed to produce a map of agricultural profit for Australia for the year 2005/2006. The process involves a complex data architecture that accounts for heterogeneous information that is collected by a variety of institutions across different scales. All information can be comfortably queried and query results can be forwarded for immediate processing and subsequent visualisation in a geographic information system (GIS). To facilitate the production of profit maps in the future, the system provides flexibility regarding an update of new economic information but it can also be linked to maps that show an updated distribution of land use. A map of agricultural profit on a large scale and regular updates thereof will help understand profit trends in time and across space. It will help identifying regions that have a lower economic profile and will inform decisions regarding the design of regulatory policies. As these maps are developed using national scale data, we do not recommend using the results at the farm level but we suggest using separate catchment scale profit assessments to calibrate the national scale profit map. The proposed system is well suited to be used in various land use management and economic scenarios and will represent a step forward regarding a scenario impact assessment on agricultural profits. It will also help understand the economic benefit of land use on a large scale.     

Integrated agricultural research and crop breeding: Allelopathic weed control in cereals and long-term productivity in perennial biomass crops

Future agricultural research will need to increasingly integrate ecological, physiological and molecular methods, in order to understand agricultural crops in situ and their interaction with the environment as well as organisms impacting on their long-term health and productivity (‘agricultural eco-genomics’). The need for integration will increasingly implicate on crop breeding strategies for most agricultural systems. In this paper, implications are highlighted for two contrasting areas of agricultural research related to sustainable crop production: first, the possibilities to utilize crop allelopathic activity to suppress weeds as an alternative to chemical weed control; and second the increasing interest to environmentally friendly and sustainable produce perennial energy crops on agricultural land. ‘Sustainability’ in agriculture is difficult to define unequivocally, but frequently implies the increased utilization of ecological processes. Breeding strategies towards increased utilization of allelopathic crops require initially the integration and verification of allelopathic processes in various agricultural contexts, because there is currently great uncertainty about the predictable operation of allelopathic activity in different ecological contexts. Breeding programs for future biomass crops, most promising are perennials such as Salix, would greatly benefit from the integration of ecological information affecting long-term productivity, e.g., eco-physiological growth determinants at stand level and the biological control of pests. Agricultural eco-genomics could facilitate a compromise between intensive agriculture and the frequently expressed demand for greater sustainability in agriculture.     

Impacts of population growth, economic development, and technical change on global food production and consumption

Over the next decades mankind will demand more food from fewer land and water resources. This study quantifies the food production impacts of four alternative development scenarios from the Millennium Ecosystem Assessment and the Special Report on Emission Scenarios. Partially and jointly considered are land and water supply impacts from population growth, and technical change, as well as forest and agricultural commodity demand shifts from population growth and economic development. The income impacts on food demand are computed with dynamic elasticities. Simulations with a global, partial equilibrium model of the agricultural and forest sectors show that per capita food levels increase in all examined development scenarios with minor impacts on food prices. Global agricultural land increases by up to 14% between 2010 and 2030. Deforestation restrictions strongly impact the price of land and water resources but have little consequences for the global level of food production and food prices. While projected income changes have the highest partial impact on per capita food consumption levels, population growth leads to the highest increase in total food production. The impact of technical change is amplified or mitigated by adaptations of land management intensities.