我国谷子种植户持续种植意愿的影响因素研究

文章通过对3个省(自治区)、5个市,268户谷子种植户的问卷调查,采用logit模型,使用逐步回归分析的方法,对影响谷子种植户持续种植谷子意愿的因素进行了分析。从户主个人基本情况、农户家庭情况、农户农业生产情况、谷子生产情况等4个方面共选择13项调查内容作为解释变量,以第2年是否持续种植谷子作为被解释变量,逐步回归分析结果表明:种植户种植业收入占家庭总收入的比重、种植户家庭耕地面积、谷子种植补贴通过了显著性检验。种植业收入占家庭总收入的比重与谷子持续种植呈显著负相关,比重越高持续种植意愿越低。谷子产量受自然因素影响大,农户从减小风险的角度出发,收入对种植业越依赖谷子的种植意愿越弱。家庭耕地面积与谷子持续种植呈显著正相关,家庭耕地面积越大,谷子被选择种植的机会也就越大,规模效应越明显,持续种植意愿越强。补贴对持续种植意愿呈显著正相关关系,种植补贴意味着更多的收益,积极性就越高。依据分析结果提出了要进一步提升对种植谷子的重视,加大科研投入力度,做好科技成果的转化与推广工作;要加大谷子种植补贴的力度、范围及内容,在良种、农膜、资金等方面对种植户给予支持与补贴,调动农户谷子种植的积极性;推进土地流转,在农户种植规模扩大过程中提高土地规模效益的政策建议。     

Estimating the supply response of cotton and cereal crops in smallholder production systems: recent evidence from Mali

Cotton is one of the most important crops in West Africa and is a major catalyst of economic development in rural areas, but the sector has suffered from a decline in the world cotton price after 1999. This article exploits an unusual data set following 82 farmers over 14 years, from 1994 through 2007, to estimate a Nerlovian supply response model for cotton, maize, sorghum, and millet in long-term rotation. The resulting system of equations is estimated with two-stage least squares (2SLS), showing that this sample of Malian cotton producers have responded to prices in a relatively inelastic manner, with supply elasticities only about one-half of those estimated for producers in developed countries. Policy reforms could help producers respond more easily to prices changes, as well as to raise average productivity levels.     

Stages and determinants of fertilizer use in semiarid African agriculture: the Niger experience

Fertilization is a stepwise decision in Niger. Survey data from a representative sample of 100 households were utilized with individual and joint estimation to evaluate the determinants of fertilizer use at its three different stages: manure alone and two different types of inorganic fertilizer application. The fertilizer price relative to the millet price was always a highly significant determinant of fertilizer adoption. Farmers' experience in seeing the results of fertilization in the field was a principal factor influencing the use of manure and of the micro‐fertilization. Other studies in semiarid regions have emphasized risk, liquidity, or fertilizer responsiveness under harsh conditions but the shift to the micro doses of inorganic fertilizer was statistically associated here with the demonstration trials and the price ratios (fertilizer/millet). A variable reflecting the millet price recovery approximately 6 months after harvest was the most important factor in the decision to raise further inorganic fertilizer use with side dressing. Policy implications were focused on the importance of demonstration trials and improvements in the economic conditions (millet–fertilizer price ratios).     

自然降雨与旱地谷子单产水平关系研究——以武安市为例

谷子抗旱性强,水分利用效率高,是我国北方干旱半干旱雨养旱作区的主要杂粮作物。文章主要研究干旱雨养旱作区降雨量对谷子单产的变化规律,从而为提高谷子降水利用效率以及实际生产提供理论依据。基于武安市1983~2012年期间30年的降雨数据和谷子单产数据,研究自然降雨与谷子单产水平关系。采用散点图、建立线性方程、线性回归显著性分析等研究方法,通过统计、对比描述等方式进行分析。结果显示:武安近30年的自然降雨量与谷子的单产之间具有正相关关系,且谷子7、8月份降雨量对其单产具有显著性影响。主要结论:谷子的单产随着降雨量的增加而增加,但不是无限增加,而是有一个最佳降雨临界点490mm;当降雨量在490mm以内变化时,谷子单产随着降雨量的增加呈现增长的趋势;当降雨量超过490mm时,谷子的单产与降雨量负相关;谷子的单产受7月和8月的降雨量影响显著,且2个月降雨量之和占全生育期的63.1%时,谷子的单产较高。     

Time‐varying Hedge Ratios: A Principal‐agent Approach

We use the classic agency model to derive a time‐varying optimal hedge ratio for low‐frequency time‐series data: the type of data used by crop farmers when deciding about production and about their hedging strategy. Rooted in the classic agency framework, the proposed hedge ratio reflects the context of both the crop farmer's decision and the crop farmer's contractual relationships in the marketing channel. An empirical illustration of the Dutch ware potato sector and its futures market in Amsterdam over the period 1971–2003 reveals that the time‐varying optimal hedge ratio decreased from 0.34 in 1971 to 0.24 in 2003. The hedging effectiveness, according to this ratio, is 39%. These estimates conform better with farmers’ interest in using futures contracts for hedging purposes than the much higher estimates obtained when price risk minimisation is the only objective considered.     

Risk and the Value of Bt Corn

A conceptual model is developed to evaluate the effect of Bt corn on risk. Results highlight the importance of distinguishing between marginal and aggregate risk effects and demonstrate that the effect of Bt corn on risk depends crucially on the price paid for the technology. Empirical results show that, depending on the price, Bt corn can be marginally risk increasing or decreasing and can either increase or decrease corn acreage. Also, depending on the price, Bt corn can provide a risk benefit to farmers, even when Bt corn is risk increasing.     

Smallholder Supply Response to Marketing Board Activities in a Dual Channel Marketing System: The Case of Zambia

In recent years, parastatal grain marketing boards have re‐emerged as important elements of grain markets in eastern and southern Africa, yet little is known about how farmers are responding to their scaled up activities. This article develops a conceptual model of farmers’ production decisions in the context of dual output marketing channels (government and private sector) when output prices at harvest time and the availability of one of the marketing channels are unknown at planting time. It then applies the model to the case of Zambia and uses nationally representative household‐level panel survey data to estimate the effects of the Food Reserve Agency (FRA), the government parastatal maize marketing board, on smallholder crop production and fallow land. The FRA buys maize from smallholders at a pan‐territorial price that typically exceeds market prices in major maize producing areas. Results suggest that increases in the farmgate FRA maize price raise farmer maize price expectations, which induces a supply response. Smallholders respond to an increase in the FRA price by extensifying their maize production. On average, a 1% increase in the FRA price is associated with 0.06% increases in smallholders’ maize area planted and quantity harvested. There is also some evidence that farmers reduce the area of land under fallow in response to FRA incentives but there is no evidence of reductions in the area planted to other crops.     

生猪养殖户从众行为存在性及形成机制研究——以四川省1127家养殖户仔猪补栏为例

[目的]多数养殖户在经营管理上往往注重短期利益,对生猪市场变化的反映是趋同的,容易在价格上涨时"一哄而上",在价格下跌时"一哄而下",这种从众行为对生猪供给造成了巨大冲击,不利于生猪生产和猪肉供给的稳定。[方法]文章以四川省12个生猪调出大县1 127个生猪养殖户为调查对象,运用二元Logistic回归法,构建了从众行为的检验模型,研究了养殖户仔猪补栏中的从众行为及其形成机制。[结果](1)养殖户仔猪补栏中存在明显的从众行为,即养殖户仔猪补栏决策明显受到其他生猪养殖者生产行为的影响;(2)从众行为服从逻辑追随律和先内后外律。当其他生猪养殖者生产效益越好时,养殖户仔猪补栏的从众行为越明显;生产规模相同的养殖户之间从众行为亦更为明显;(3)信息获取性从众和投机性从众是引起从众行为形成的内在原因;(4)生产规模及养殖技术对从众行为存在重要影响。[结论]厘清了养殖户生产中出现"一哄而上,一哄而下"群体性行为的原因,为理解生猪养殖者从众行为及生猪价格形成机制提供新的视角,丰富了农户行为及农产品价格形成机制的研究成果。     

On-farm biological control of the pearl millet head miner: realization of 35 years of unsteady progress in Mali,Burkina Faso and Niger

The pearl millet head miner became a major pest in the West African Sahel during the droughts of 1972–1974, and has since remained a threat to food security. Pesticide control is unrealistic for subsistence farmers. Furthermore, there are no cultural control methods or genetic sources of resistance. Biological control was a possibility, but the required ecological knowledge did not exist in the 1970s. A biological control programme could have been rapidly developed through sustained and coordinated funding using existing knowledge. Instead, it took 25 years to lay the scientific groundwork through occasional bursts of uncoordinated short-term activity using international scientists funded by large donors. There was little funding and few prominent roles for national scientists until 2000, when they were empowered by a different approach taken by the McKnight Foundation. An operational system was quickly developed and deployed in which trained farmers rear and release the parasitoid Habrobracon hebetor to effectively eliminate the head miner. The national programme scientists demonstrated admirably that, when trusted and adequately supported and empowered, African researchers can deliver real and effective solutions that are scientifically sound, meet the needs of smallholder farmers, and contribute significantly to improved food security, community resilience and reduced poverty.     

Soil Fertility Management and Compost Use in Senegal's Peanut Basin

The Jóór (Dior) soils of Senegal's Peanut Basin are inherently low in organic matter, limiting yields of millet and other crops and threatening the food security of smallholders. Focus groups and interviews were conducted in eight villages to characterise the site-specific fertility management by farmers in the Peanut Basin. Results of the qualitative survey revealed that farmers base management decisions on a series of fertility indicators that include type, colour, and texture of soil, presence of vegetation, and productivity in previous years. In an effort to equalise fertility across the field, farmers amend areas they classify as less fertile with decomposed manure and household waste from the family sëntaare (traditional pile) orwith compost from managed piles. On-site measurements of soil in areas of fields amended with compost or sëntaare material revealed significant increases in peanut and millet growth over unamended areas, but little difference between the effects of compost and manure. Similarly, chemical analysis revealed increased effective cation exchange capacity (ECEC) and nutrient concentrations (K, Mg and Al) in soils amended with compost or manure. Similarities in the chemical characteristics of compost and sëntaare material suggest that development workers could emphasise improved pile management rather than promoting more labour-intensive composting.     

宁夏中部干旱带发展高产杂交谷子产业的建议

宁夏水资源严重匮乏,在全球气候变暖背景下,中部干旱带干旱有所加剧,水资源供需矛盾日益突出,粮食产量长期低而不稳,生态移民脱贫压力大,生存与发展问题突出。2010年以来,宁夏气象部门在中部干旱带成功引种了杂交谷子系列品种,并开展了大量试验,累计推广近666.7hm2。在2011年极旱年份下将高产杂交谷子与当地主栽作物种植的成本效益及前景进行了对比分析。分析表明,杂交谷子节水、抗旱性强,比当地传统谷子稳定增产1倍以上,加上小杂粮价格较高,农民收益普遍高于种植其它作物。在张杂谷引种试验及示范推广的基础上,结合农业气候资源分布状况,制作了宁夏张杂谷栽培的气候适宜性区划图,得出不同地区适宜发展的品种、种植方式及种植风险。建议在宁夏中部干旱带积极稳妥发展杂交谷子种植,加强杂交谷子高产栽培与节水种植技术培训,建立谷子种植-加工-销售一条龙服务体系,使之成为中部干旱带农民增收致富的新途径之一。     

Risk management strategies using seasonal climate forecasting in irrigated cotton production: a tale of stochastic dominance

Decision-making in agriculture is carried out in an uncertain environment with farmers often seeking information to reduce risk. As a result of the extreme variability of rainfall and stream-flows in north-eastern Australia, water supplies for irrigated agriculture are a limiting factor and a source of risk. The present study examined the use of seasonal climate forecasting (SCF) when calculating planting areas for irrigated cotton in the northern Murray Darling Basin. Results show that minimising risk by adjusting plant areas in response to SCF can lead to significant gains in gross margin returns. However, how farmers respond to SCF is dependent on several other factors including irrigators' attitude towards risk.     

Hedging Opportunities for Canadian

The unprecedented commodity price volatility in the last decade has resulted in a growing interest in futures trading by farmers. One of the major reasons often provided for the usefulness of commodity futures markets is that they provide a mechanism whereby producers can shift the risk of price change onto others. Interestingly, little research has been conducted on the effectiveness of the WCE as a hedging tool for farmers.
The objective of this paper was to investigate the extent to which the futures contracts for rapeseed, barley and flaxseed can be used by farmers in order to reduce price risk (measured by volatility). Drawing on earlier literature, the theory of hedging was reviewed and formulae for estimating the optimal hedge and the effectiveness of hedging were presented. An empirical analysis determined that the Winnipeg rapeseed, barley and flaxseed futures contracts are very useful in terms of allowing a producer the opportunity to reduce exposure to price risk.     

SUPPLY RESPONSIVENESS OF RICE FARMERS IN LAGUNA,PHILIPPINES

The supply response and input demand by farmers using modern rice technology in Laguna, Philippines were estimated using profit function analysis. The results indicate that farmers do maximise short-term profits and respond to price changes efficiently. The supply elasticity of rice with respect to its own price was approximately unity. Changes in real wages were estimated to have a greater impact on rice profit and supplies than changes in the real prices of mechanised land preparation, fertiliser or pesticides. Production elasticities derived from the profit function were consistent with those estimated directly from the underlying production function.     

Determinants of millet diversity at the household-farm and village-community levels in the drylands of India: the role of local seed systems

This research characterizes the biological diversity of millet crops in the semiarid regions of India at the household and village‐community ( panchayat) scales of analysis, placing that evidence in the context of local seed systems. A set of seed system parameters that span formal and informal exchange and can be measured empirically are proposed. The analysis is based on data collected through sample surveys of farmers and traders in selected sites of Karnataka and Andhra Pradesh, combined with cultivar taxonomies developed with geneticists and applied to seed samples. Findings demonstrate that millet crop diversity levels at both scales of analysis are significantly influenced by seed system parameters, factors which related studies have omitted. In particular, the presence of active local (formal and informal) seed markets enhances millet richness among and within farming communities. Crop improvement strategies oriented toward local seed markets could provide important benefits and incentives to farm households living in these marginal environments. There is a need, however, for an enhanced theoretical understanding of local seed markets in analyzing crop variety choices and the diversity of materials grown in less favored environments.     

Short supply chain participation and market performance for vegetable farmers in China

The fresh food supply chain in China has begun to reduce the number of intermediaries that connect producers and consumers. Using farm‐level data, this paper investigates the impacts of short supply chain participation on vegetable farmers’ market performance, including profits, productivity, production cost, price and price risk. The results show that the participation in a short supply chain is a profit‐maximising strategy and risk management tool for farmers. The increase in profit is attributed to productivity advantages, farm size expansion, and risk reduction rather than because of price premiums or cost savings. A policy implication is that short supply chain promotion has many benefits, but the government should be more concerned about the sustainability of short supply chains.     

Use of Compliance Rewards in Agri‐environmental Schemes

Ensuring that farmers comply with the terms of agri‐environmental schemes is an important issue. This paper explores the use of a ‘compliance–reward’ approach under heterogeneous net compliance costs with respect to cost‐share working lands programmes such as the Environmental Quality Incentives Program (EQIP) in the United States. Specifically, we examine the use of a reward under asymmetric information and output price uncertainty. We examine two possible sources of financing under the assumption of budget neutrality: (i) funds obtained by reducing monitoring effort; and (ii) money saved by reducing the number of farmers enrolled. We discuss the advantages and disadvantages of each source of funding and analyse these numerically for both risk‐neutral and risk‐averse farmers. We also examine the trade‐off between increased expenditure on monitoring effort and compliance rewards when additional budgetary resources are available. We show that under certain conditions a compliance reward can increase compliance rates. For risk‐averse farmers, however, conditions that ensure a positive outcome become more restrictive.     

Landlords and farmers: implications of disparities in bargaining power for tenancy in agriculture

The equilibrium allocation of owner operated and rental land in the agricultural sector is examined given risk averse agents, risky returns and asset price risk. The model is extended to account for disparities in bargaining power among landlords and farmers. In the absence of disparities, the competitive equilibrium allocation satisfies the general conditions for optimal risk sharing with an adjustment factor similar to the optimal hedge ratio. Differences in bargaining power result in deviations from the optimal risk sharing conditions. Numerical simulations of tenancy structure are conducted for a developed agricultural economy exposed to various forms of risk. Estimates of parameter values representing the riskiness of returns and asset prices in this study are based on vector auto regressive techniques. The simulations show that a substantial reduction of the rental ratio is obtained in a situation where farmers are equally or more risk averse than landlords. Consequently, the results indicate that the importance of the tenancy institution as a risk sharing mechanism is severely mitigated in the presence of asset price risk, risky returns, relatively risk averse farmers and disparities in bargaining power.     

Price transmission,asymmetric adjustment and threshold effects in the cotton supply chain: a case study for Vidarbha,India

This study examines price transmission asymmetries in Vidarbha's (India) cotton supply chain from 2002 to 2012. The analysis takes account of thresholds in price adjustments toward their long‐run equilibrium. The first stage considers the price dynamics between international and Indian domestic cotton prices. The second stage considers price transmission from domestic to farm gate cotton prices in Vidarbha. Results from the first stage indicate that Indian and international cotton markets are well‐integrated. In contrast, the second stage reveals significant threshold‐type nonlinearities as well as asymmetries in price transmission between domestic and farm gate prices. The short‐run dynamics suggest that the pass‐through from domestic to farm gate prices is larger when domestic prices decrease than when they increase. Moreover, back of the envelope calculations suggest that the loss in revenue for a typical farmer from a decrease in domestic price is larger than the gains from an increase in domestic price of the same magnitude. The implication is that traders benefit from price fluctuations at the expense of farmers. Evidence from fieldwork in Vidarbha suggest that asymmetries revealed in this analysis may be linked to trader's market power and inadequate market information among farmers.     

Drought‐tolerant rice,weather index insurance,and comprehensive risk management for smallholders: evidence from a multi‐year field experiment in India

In rainfed production systems throughout India, agricultural activities are dependent upon the summer monsoon, and any aberration in monsoon rainfall patterns can have severe consequences for rice production. There is considerable policy interest in designing programs to lower small‐scale farmers’ exposure to these types of risk given the regularity with which adverse monsoon events occur. This paper introduces a field experiment conducted with two risk management options in the state of Odisha: a drought‐tolerant rice cultivar; and a weather index insurance product designed to complement the performance of the cultivar. Uptake rates for the cultivar itself and for the joint product are compared across two years alongside an analysis of factors that predict uptake. Results indicate high levels of demand for both the products, albeit with a significant degree of price sensitivity. But this sensitivity is agnostic to the nature of price reductions, suggesting that public investments that lower the costs of risk management may be sufficient to encourage broad uptake, without necessarily relying upon distortionary subsidies as is so often done. Sustained demand between years one and two is primarily explained where individuals were indemnified in year one and had a large number of peers also purchasing the product.