Nitrogen Management for Profitable Farming with Minimal Environmental Impact: The Challenge for Mixed Farms in the Cotswold Hills,England

A detailed nitrogen (N) budget was constructed for a mixed farm in the Cotswold Hills, England, situated on thin, well drained soils prone to leaching. The study covered all stages of the farm's seven-year rotation and included the removal of the dairy herd. All inputs and outputs of N were measured or estimated and a balanced budget achieved, but only by including relatively expensive measurements of soluble organic nitrogen (SON) leached. Leaching was the main loss process. Given the nature of the soil and the influence of the weather, it would be difficult to reduce losses without drastic reductions in fertiliser inputs or stocking rates. Nitrogen use efficiency averaged 46%. The mean N surplus declined from 141 kg N ha^?1 to 117 kg N ha^?1 with the removal of the dairy herd. However, the farm to which the herd moved had an N surplus of 392 kg N ha^?1. Simple farm gate N budgets were constructed for neighbouring Cotswold farms to encourage farmers to consider ways to improve N use. Implications for policy to reduce losses of N while maintaining farm profitability are discussed.     

The influence of management decisions and external factors on the dairy farmer's environmentally friendly farming objective: the Green Dairy experience

Ten dairy farms participated in an EU project that aimed to improve nitrogen use and assist with the adoption of more environmentally friendly farming practices. Nitrogen use and management decisions were monitored during 2003, 2004 and 2005. Nine farms improved nitrogen use (nitrogen output relative to input) in Year 2. Four farms maintained or further improved nitrogen use in Year 3. Management decisions and external factors that improved nitrogen use were increasing farm milk output, adopting best management practices for nitrogen use, growing forage crops that required less nitrogen than grass and favourable crop production conditions that rendered large quantities of good quality forage. Decisions that worsened nitrogen use were increasing cow numbers without sufficient management support, the late start of supplementary feeding when grass quality declined, setting the target yield too high, pursuing a higher milk price, less palatable silage and disease. Sufficient slurry storage is essential to improving nitrogen use. The savings from lower nitrogen input and the revenue from milk were in no proportion to the investments required for additional slurry storage, however. The farmers did adopt environmentally friendly practices, but only to the degree their businesses were able to sustain.     

On-Farm Nutrient Balance Studies in the Dry Zone of Myanmar

On-farm experiments to study soil fertility depletion—one of the biophysical factors limiting crop production—were conducted in six villages of central Myanmar during 1997 to 1999. Systematic socioeconomic surveys and analysis of socioeconomic and crop production factors aided the selection of farmers.

Topsoil mineral nitrogen content at the start of the cropping season was high (10–25 mg N kg^?1). Available phosphorous was around the threshold level for most crops, but exchangeable potassium was low. The predominant continuous cropping system of sole groundnut was on average positive for P (0.24 kg ha^?1 y^?1) and K (7.05 kg ha^?1 y^?1) and negative for N (?32.4 kg ha^?1 y^?1). A negative balance for N in the groundnut/pigeonpea (?58 kg ha^?1 y^?1) and mung bean/pigeonpea (?56 kg ha^?1 y^?1) intercropping systems was noted. The nutrient balances were positive in early sesame—late sesame (29 kg N ha^?1 y^?1, 8 kg P ha^?1 y^?1, 33 kg K ha^?1 y^?1) and early sesame/pigeonpea (8 kg N ha^?1 y^?1, 15 kg P h^?1 y^?1, 44 kg K ha^?1 y^?1) production systems while sole sorghum system resulted in positive balance for N (23.8 kg ha^?1 y^?1) and negative balance for K (?3.8 kg ha^?1 y^?1).     

Long-term effects of crop residues and fertility management on carbon sequestration and agronomic productivity of groundnut–finger millet rotation on an Alfisol in southern India

The data from long-term management and cropping systems experiments are needed to assess changes in soil quality, organic carbon pool, and agronomic sustainability. Thus, a 13-year-old soil fertility management experiment was used to assess the impact of crop residues carbon (C) inputs on SOC stock in a rainfed groundnut (Arachis hypogeae L.)–fingermillet (Eleusine coracana (L.) Gaertn) rotation in semiarid alfisol. The application of farmyard manure (FYM) alone or in a combination with chemical fertilizers contributed to higher amounts of C inputs and subsequently to build up a higher SOC pool. Application of 10?Mg?ha^?1 of FYM and a recommended dose of chemical fertilizer (25:21.8:20.7 and 50:21.8:20.7?kg?N, P, K ha^?1 for groundnut and fingermillet, respectively) increased soil SOC pool by 41.2% to 73.0?Mg?ha^?1 with an increase of 9.3?Mg?ha^?1 over 13 years. Both SOC pool and rates of its sequestration were positively correlated with cumulative C input and sustainable yield index. A minimal input of 1.62?Mg?C?ha^?1?yr^?1 is needed to maintain SOC pool at the antecedent level. Balanced application of NPK fertilizers is needed to reduce and reverse the depletion of SOC pool.     

生产方式的转变对元阳哈尼梯田系统氮磷平衡的影响

目的 研究长时间尺度下生产方式的改变对梯田系统物质流动模式的影响,可为保护哈尼梯田、合理开发利用哈尼地区生态资源、实现哈尼梯田的可持续利用提供科学依据。方法 文章采用人类活动净氮/磷输入模型（NANI/NAPI）对1985—1986年、2009—2020年元阳县两个不同发展时期的NANI和NAPI及其相关构成进行核算。结果 （1）元阳县NANI、NAPI整体呈现先上升后下降的趋势,NANI和NAPI在1985年分别为2 914 kg/（km²·年）和249 kg/（km²·年）,到2016年均达到最高值,分别为9 860 kg/（km²·年）和685 kg/（km²·年）,随后呈现下降趋势,到2020年分别降至6018 kg/（km²·年）和321 kg/（km²·年）。（2）NANI的4个组成中,食品/饲料净氮输入占20%~45%、沉降氮输入占12%~40%、作物固氮输入占6%~12%、肥料氮输入占5%~52%;NAPI的3个组成中,食品/饲料净磷输入3%~50%、肥料氮输入占32%~57%、非食品磷输入占19%~41%。（3）元阳县NANI/NAPI比值存在明显阶段性变化,1985年和1986年NANI/NAPI比值分别为11.7和11.0,至2018—2020年基本稳定在18.5~18.8左右。（4）从NANI、NAPI与其组成的相关关系看,NANI与食品/饲料氮输入的R²为0.81（P＜0.01）,与化肥氮输入的R²为0.81（P＜0.01）;NAPI与食品/饲料磷输入的R²为0.90（P＜0.01）,与化肥磷输入的R²为0.59（P＜0.01）。结论 元阳县NAPI与NANI变化趋势呈现高度一致,均为先上升后下降的阶段性变化,与当地生产方式的转变相契合。     

Contract farming and smallholder incentives to produce high quality: experimental evidence from the Vietnamese dairy sector

In emerging markets for high‐value food products in developing countries, processing companies search for efficient ways to source raw material of high quality. One widely embraced approach is contract farming. But relatively little is known about the appropriate design of financial incentives in a small farm context. We use the example of the Vietnamese dairy sector to analyze the effectiveness of existing contracts between a processor and smallholder farmers in terms of incentivizing the production of high quality milk. A framed field experiment is conducted to evaluate the impact of two incentive instruments, a price penalty for low quality and a bonus for consistent high quality milk, on farmers’ investment in quality‐improving inputs. Statistical analysis suggests that the penalty drives farmers into higher input use, resulting in better output quality. The bonus payment generates even higher quality milk. We also find that input choice levels depend on farmers’ socio‐economic characteristics such as wealth, while individual risk preferences seem to be less important. Implications for the design of contracts with smallholders are discussed.     

Modelling stochastic crop response to fertilisation when carry-over matters

Soils in a large part of Niger's agricultural area are sandy and very low in nitrogen (N), phosphorus (P) and organic matter. This low soil fertility combined with low and erratic rainfall constitutes a severe constraint on food cropping in the area. Although agronomists have advised chemical fertilization as a means of improving soil fertility, little fertilizer has been used in this area of the world. The economic management of soil fertility in the agricultural area of Niger is analyzed using a dynamic model of farmer decision-making under uncertainty. The model is based on agronomic principles of plant growth and accounts for the carry over of P, an immobile nutrient. At current input prices, a soil P content of at least 14 ppm is found to be desirable. This target is above the natural soil fertility level of about 3 ppm. It can be maintained with a moderate annual application (12 kg P₂O₅ ha^?1) of simple superphosphate. Results also suggests that returns to N fertilization are too low and variable to warrant the use of this input.     

Reduced tillage and nitrogen effects on soil water dynamics and maize (Zea mays L.) yield under semi-arid conditions

Soil water and nutrients are critical drivers of crop production for smallholders of southern Africa. A three-year study was conducted to assess the effect of integrating single and double ploughing, ripping and planting basins with nitrogen fertilizer (0, 10 and 20?kg?N?ha^–1) on soil water dynamics and maize (Zea mays L.) yields. The experimental design was factorial with four tillage methods and three nitrogen levels as treatment factors. The study was conducted under semi-arid conditions of Zimbabwe. Tillage methods had similar soil water patterns in the profile and no tillage?×?N interaction effects were observed on soil water dynamics. Soil water penetrated deeper into the profile under ripper and basin methods than conventionally ploughed treatments. Nitrogen increased maize yields (14–96%) and rainwater-use efficiency (20–92%) regardless of tillage methods and growing season quality. However, more studies are required to explore complementary techniques that can improve rainwater capture and prolong soil water storage, and improve soil fertility.     

Improving China’s food and environmental security with conservation agriculture†

China has achieved impressive increases in agricultural output in recent decades. Yet, past approaches centred on a growing use of fertilizers, pesticides, fuel and water are not likely to achieve the required 30–50% additional increases in food production by mid-century. We show that efficiencies of production are falling and the costs of environmental harm are increasing. Agricultural innovations that improve natural capital are urgently needed. Conservation agriculture (CA) is now practised on >8?Mha in China and is offering promising prospects of both enhanced yields and environmental services. Our meta-analysis of 60 papers with 395 observations in China shows notable benefits from CA. Mean yield increase was 4.5% or 263?kg?ha^?1 for wheat, 8.3% or 424?kg?ha^?1 for maize, and 1.65% or 250?kg?ha^?1 for rice. In 34 datasets from 22 published papers (experimental duration: 2–17 years), 26 datasets (76.5%) show that CA increased yield and soil organic carbon (mean SOC increase of >3?g.kg^?1 in 0–10?cm soil depth) when compared with traditional tillage. Key priorities for the spread of more sustainable forms of agriculture in China are national policy and financial support, better coordination across agencies, and better extension for farmers.     

USING INPUT DEMAND AND PRODUCTION FUNCTION MODELS TO ASSESS THE NET BENEFITS OF DAIRY HERD IMPROVEMENT

Two methods of evaluating (the net social benefits of the dairy herd-improvement scheme operated by the New South Wales Department of Agriculture are described. The first involves derivation of 'an input demand' function for the herd-recording aspect of the scheme and use of this function to estimate the economic surplus (net of both private and public costs) provided by the service. The second approach involves deriving a production function for milk from which it is possible to estimate the contribution herd-recording and artificial breeding have made to increasing milk yields per cow. Social benefits are shown to have been less than social costs for herd-recording, however dairy farmers have made net private gains. The herd-recording scheme has contained a regressive subsidy element. The production function approach show that artificial breeding and herd-recording were profitable complements in production.     

河南省不同典型农业生产区玉米施肥现状及增产潜力评价

[目的]通过调研2017年河南省不同典型农业生产区玉米的施肥现状,发现河南省玉米种植效益普遍较低主要与化肥不合理施用相关,提出相应的施肥建议以获得最大增产。[方法]采用实地问卷调查的方法,选择河南省禹州、长葛(两个粮食作物种植区)、杞县(一个经济作物种植区)3个典型农业经济区域作为调查地点,共调查了828家农户玉米的产量、施肥种类、施肥量、施肥时间、施肥方式等。[结果]河南省粮作区玉米产量为4 500.00～10 500.00kg/hm~2,养分投入量为90.00～1 249.00kg/hm~2,且仅有单质肥料和复合肥的投入,禹州、长葛两地粮作区平均PFP分别为19.18%和22.46%,、增产潜力分别为23%和26%;杞县经作区玉米产量在4 731.00～11 320.00kg/hm~2,养分投入量为0.00～1 206.00kg/hm~2。经作区有机肥的投入,使其肥料种类相对较多,该区域平均PFP为31.19%,平均增产潜力为34%。[结论]根据当地土壤肥力,粮作区玉米种植可适当减少氮肥投入量,降低基追比,增施磷钾肥,改进后玉米有20%～30%的增产潜力;经作区玉米种植严格把控氮磷钾的配施,增施有机肥,增加基肥种类,改进后玉米有30%～40%的增产潜力。     

Higher Intensity,Higher Profit? Empirical Evidence from Dairy Farming in New Zealand

Over the last two decades there have been significant and well‐documented changes in the nature and structure of New Zealand dairy production. One particular feature has been a marked shift in the ‘input intensity’ of dairy farming systems through increased use of supplementary feed. These changes have generated debate about the impact of dairy farm intensity on the performance of farm businesses and the competitiveness of the New Zealand dairy sector. Using a novel econometric approach, we assess statistically the impact of three types of dairy farming systems on milk production and financial performance, using farm business data provided by DairyBase^®. Our empirical results show that higher input systems perform significantly better physically than lower input systems, but not financially. The disaggregated analysis suggests that the average treatment effects differ by region and performance quantiles.     

农户减少化肥用量和采用有机肥的意愿研究——基于洱海流域上游面源污染防控的视角

[目的]过量施用化肥导致水体富营养化是造成洱海流域上游面源污染的主要原因之一,调查分析农户减少化肥用量和采用有机肥的意愿有助于了解其调整施肥结构的行为。当前研究忽视了农户减少化肥施用强度和采用有机肥的意愿间的替代性,未能开展联立研究。[方法]基于洱海流域上游397个水稻种植户的问卷调查数据,通过Bivariate-Probit模型对农户减少化肥用量和采用有机肥两种意愿进行分析。[结果]年龄负向影响农户减少化肥量的意愿,农户对有机肥好处的认知正向影响其减少化肥量的意愿,农户参加农业社会化服务对其减少化肥用量和采用有机肥的意愿均产生正向影响,相比之下,对农户采用有机肥意愿的促进作用更大。[结论]引导农户参加农业社会化服务以及加强宣传和培训,提高农户对有机肥作用的认知可能是加强其减少化肥用量和增加有机肥施用量意愿的有效途径。     

Cost‐effective regulation of nonpoint emissions from pastoral agriculture: a stochastic analysis

Nutrient emissions from pastoral agriculture are a global cause of declining water quality. Their management is complicated through variability arising from climate and soil influences. This paper compares the implications of input‐based policies and direct restrictions on leaching to achieve 10 and 20 per cent reductions in nitrogen (N) load, in the context of pasture‐based New Zealand dairy farms. The most important mitigation practices on these farms are de‐intensification (involving reductions in N fertiliser application and stocking rate) and the application of nitrification inhibitors. A stylised conceptual model, incorporating both sources of variability, is used to identify the implications of alternative policies. Direct restriction of estimated N leaching is the most cost‐effective policy to reduce N leaching by 10 and 20 per cent. These results indicate the general insufficiency of input‐based mechanisms for water quality improvement, given the low correlation between input use and leaching, possible substitution with unrestricted inputs and their failure to motivate the use of mitigation strategies. Additionally, model output indicates that inherent variability in water quality, mainly due to climate influences, can dominate the benefits of regulatory action in any given year.     

An in-depth examination of maize yield response to fertilizer in Central Malawi reveals low profits and too many weeds

We examine the productivity of fertilizer used on maize in Central Malawi using field-level panel data from over 1,200 observations on more than 500 fields over 4 harvest years. There are several novel aspects of this analysis compared to other on-farm fertilizer efficiency studies, including (a) precise and accurate yield measurement using crop cuts, (b) estimating the impact of timely weeding, (c) the use of data on multiple soil characteristics from a panel of soil samples, and (d) the ability to control for field-level fixed effects by tracking the same land over time. We find critical ecological and management threshold effects on fertilizer effectiveness at 0.94% soil carbon content, 57–58% sandiness, and weeding within 4 weeks of planting. Overall, we estimate lower yield response to fertilizer than reported in earlier studies: 2.6 maize kg/N kg under ideal circumstances, and statistically nil under many other conditions. We discuss the implications of our findings for farmers, policymakers, and researchers.     

Scale Economies,Technical Efficiency,and the Sources of Total Factor Productivity Growth of Quebec Dairy Farms

Canada's average cost for milk production is among the highest in the world. This paper focuses on specific potential causes by estimating economies of scale and technical efficiency for a panel of Quebec dairy farms that spans the 2001–10 period. Additionally, this paper investigates the sources of total factor productivity growth. The stochastic frontier analysis, based on an input‐distance function, is used to estimate returns to scale relationships across dairy farms. The results show that there is significant economies scale to be exploited and that cost of production could also be reduced by improving technical efficiency. Accordingly, the paper indicates that input‐mix effect is the main source of total factor productivity growth. The results have important implications for Canada's supply management policy, and more specifically for the trading of production quota between dairy farmers, as well as for the delivery of targeted extension services.     

基于面源污染约束的油菜生产效率时空变化及成因分析

[目的]分析面源污染约束条件下我国油菜生产效率的动态变化、省际差异及其影响因素,提出提升途径。[方法]采用基于非期望产出的非径向、非角度的数据包络分析模型测算面源污染约束下的油菜生产效率,根据投入冗余、期望产出不足或非期望产出冗余等,分析效率损失成因。[结果]我国油菜生产效率总体上呈现"N型"年际变化特征,其中黄淮区、江浙、重庆、青海和甘肃的油菜生产效率均值高于0.9,云贵和内蒙古的油菜生产效率则低于0.8。全国和长江流域省际差异表现为先扩大后缩小趋势,西北区省际差异最大,黄淮区省际差异最小。总氮和总磷排放量过高是长江流域乃至全国油菜生产效率损失的主要原因。近3年总氮可缩减比例均值大于30%的地区从大到小依次为湖南、内蒙古、贵州、云南和江西,总磷可缩减比例均值大于30%的地区依次为云南、贵州、四川和内蒙古。此外,湖北用工投入冗余、内蒙古化肥投入冗余和单产不足也是其油菜生产效率损失的重要原因。[结论]长江流域需重点削减氮磷径流损失,黄淮区应重点控制氮磷淋溶损失,西北区应重点治理氮磷侵蚀流失。     

Municipal commonage policy and livestock owners: Findings from the Eastern Cape,South Africa

The new African National Congress government announced after 1994 that municipal commonage would be a pillar of their land reform programme. The Department of Land Affairs spearheaded this by acquiring new land to complement the existing ‘old’ commonages. The aim of old commonage was to supplement the income of poor urban residents through the subsistence user system whereas new commonage was intended as a ‘stepping stone’ for emergent farmers. We investigated the differences between old and new commonage farmers as well as how they perceived the Makana local municipality's capacity to manage the commonage. The results showed that local institutions were weak. Only 46% of the old commonage farmers were members of a local livestock association whereas 74% of the new commonage farmers were members. Most old commonage farmers (59%) were dissatisfied with local government's management of the commonage. In contrast, only 37% of the new commonage farmers were dissatisfied with the management of the commonage. There were no differences between old and new commonage farmers in terms of livestock owners’ characteristics and mean annual net direct-use value of livestock. There were also no differences in the age of the two types of commonage farmers. Furthermore, there was no association between the type of commonage and level of education. The mean annual net direct-use value of livestock on old commonage was R6308 compared with R9707 on new commonage. Although the income from livestock for new commonage farmers varied slightly from that of old commonage farmers, the annual productive output per farmer on old commonage was R473 ha⁻¹, three times higher than that of new commonage farmers which was R134 ha⁻¹. We suggest that new land policy legislation is needed in which poverty as well as the legal arrangements between all stakeholders is clearly defined. Furthermore, national departments need to be more involved with local municipalities to increase local management capacity.     

The links between management's critical success factors and farm level economic performance on dairy farms in Sweden

Management's critical success factors (MCSFs) are used to indicate how farm profits develop, but their usefulness as profitability predictors has previously not been analyzed statistically. This paper explores the usefulness of some commonly used MCSFs in Swedish dairy farms, by investigating whether the MCSFs are significant predictors of economic efficiency. Further, the paper takes a comprehensive view of evaluating farm level efficiency, in that all major input and output efficiency scores are estimated. Previous literature has focused on only one score, or on only one perspective. Our results show that cost efficiency is the more problematic part of the profitability process. Especially the allocative part needs to be improved. Moreover, the results show that the MCSFs milk quality, herd fertility and involuntary culls ratio may not work as indicators of economic performance, whereas milk yield per cow and the mastitis ratio are significant indicators.     

基于SFA模型的河南省粮食产量时空变化及投入要素影响

[目的]粮食问题影响着一个国家的国民经济发展和人民生产、生活,农业在整个社会生产活动中占有重要地位,河南省是全国农业大省,对河南省粮食产量进行分析具有重要的现实意义。[方法]以2005—2015年河南省各县粮食产量和投入要素为研究对象,将研究数据面板化,利用线性相关、随机前沿生产函数模型、脱钩分析等方法,运用ArcGIS 10.1、Eviews 8.0和SPSS 19.0等软件,对河南省各县粮食产量时空变化、投入要素影响程度和脱钩效应进行分析。[结果]模型运算结果表明文章选用模型效果较好,能够反映粮食产量的时空变化以及其与投入要素之间的关系,且符合河南省粮食产量实际情况。研究结果表明:(1)从时间上来看, 2005—2015年河南省粮食产量总体呈线性上升趋势;(2)从空间上来看,河南省中部、北部、东部和南部粮食产量较高,西部受地势因素影响粮食产量较低;(3)粮食产量与化肥施用折纯量、粮食播种面积、农民经营性收入、农药施用量、农业机械总动力和乡村农业人口呈正相关关系,与农村用电量呈负相关关系;(4)化肥施用折纯量、农村用电量、农药施用量存在脱钩效应,粮食播种面积、农民经营性收入、农业机械总动力不存在脱钩效应。[结论]应保持目前粮食播种面积不变,提高农业机械总动力,突出投入要素的影响,同时对河南省各县进行区域功能定位。