Farmers＇ Character and Behavior of Fertilizer Application - Evidence from a Survey of Xinxiang County, Henan Province, China

Agricultural chemical use has caused a public concern over environmental issue while decisions about applying chemicals are made by individual farmers. The critical decision-making role of farmers relative to agricultural chemical use creates a need for accurate information on their perceptions of various chemical-related hazards and the factors that may influence such judgments. Based on data collected from 177 land operators at Xinxiang County in Henan Province of China, an empirical analysis is conducted to examine the relationship between farmers＇ character and the behavior of fertilizer application. Study findings reveal that： the characteristics of household head and household, and the nature of farming management positively affect the amount of fertilizers applied; information on fertilizers and the knowledge about environmental impact of fertilizer application have negative impacts by contrast. To formulate effective pollution control policies at the farm level, it is imperative for policy-makers to convey information to producers by demonstration projects, technical assistance, and education programs. Under a changed political environment, some combination of education and economic incentives could be lower cost and more effective tools for achieving desired environmental conservative goals.     

Improving Water Use Efficiency of Wheat Crop Varieties in the North China Plain： Review and Analysis

The North China Plain (NCP), one of the most important agricultural regions in China, is facing a major water-resource crisis evoked by excessive exploitation of groundwater. To reduce water use while maintaining high crop production level, improving variety water use efficiency (WUE) is an urgent need, especially because other water-saving measures such as water delivery, irrigation, and agricultural practices have already achieved most possible progresses. Evaluation of variety WUE can be performed accurately at the individual plant level (WUEp). Reviewing the studies on physiological factors affecting WUE p performed up to date, stomatal conductance was considered to be an important trait associating closely with WUE p . The trait showed a large degree of varietal variability under well-watered conditions. Crop varieties differ highly in sensitivity of stomata to soil and air drying, with some varieties strongly reducing their stomatal conductance in contrast with those lightly regulating their stomata. As a result, difference among varieties in WUE p was enlarged under water deficit conditions in contrast with those under well-watered conditions. The relationship between stomatal conductance and yield depends on water availability of whole growing period in local areas. Usually, large stomatal conductance results in a high yield under good irrigation system, whereas a low stomatal conductance can lead to yield benefit under limited stored soil moisture conditions. In the NCP, winter wheat is the largest consumer of irrigation water, improvement strategies for high WUE aiming at wheat crops are in urgent need. We suggest, for the well-irrigated areas with excessive exploitation of groundwater, the wheat breeding program need to combine medium stomatal conductance (0.35 mmol H2O m-2 s-1 or so), high carboxylation efficiency, and high harvest index. Areas with partial/full access to irrigation, or infrequent drought, should target wheat varieties with high stomatal conductance under no water stress and low sensitivity of stomata to soil water deficit. Drought-prone rain-fed areas characterized by frequent and long terminal drought should target wheat varieties with low stomatal conductance under no water stress and high stomata sensitivity to soil drying to make water available during grain filling.     

Household and Community Assets and Farmers＇ Adaptation to Extreme Weather Event： the Case of Drought in China

Under climate change, rising frequency and serious extreme weather events have challenged agricultural production. Designing appropriate adaptation measures to the extreme weather events require rigorous and empirical analysis. The overall goals of this study are to understand physical adaptation measures taken by farmers and the impacts of household and community assets on farmers＇ adaptation when they face drought. The analyses are based on a unique data set collected from a household survey in three provinces in China. The survey results show that though not common on annual basis, some farmers did use physical adaptation measures to fight drought. Regression analysis reveals that both household and community assets significantly affect farmers＇ adaptation behaviors. Improving households＇ social capital and wealth, communities＇ network and access to government＇s anti-drought service can facilitate farmers＇ adaptation to drought. Results indicate that community＇s irrigation infrastructure and physical adaptation taken by farmers can substitute each other. Further analysis shows that the households taking adaptation measures have higher crop yields than those without taking these measures. The paper concludes with several policy implications.     

Welfare and Market Impacts of Food Safety Measures in China：Results from Urban Consumers’ Valuation of Product Attributes

This study provides an economics assessment of various food safety measures in China. A choice experiment approach is used to elicit Chinese consumer preferences for various food safety attributes using data from a 2008 urban consumer survey. An alternative welfare calculation is used to model aggregate market impacts of select food safety measures. Our results show that the largest welfare gains are found in the current government-run certiifcation program. The implementation of a third-party certiifcation system, a traceability network and a product label would generate signiifcant value and would help reduce current system inefifciencies in China. This study builds on previous research and provides an alternative approach for calculating consumer valuation of safety and quality attributes that can be used to estimate aggregate economic and welfare impacts.     

Analysis on Technical Efficiency of Rice Farms and Its Influencing Factors in South-western of Niger

The present study focused on analyzing the technical efficiency of rice farms in southwest of Niger. The data from January to March 2015 survey of 148 ms in three districts of south-western of Niger were analyzed by using DEA-Tobit two-step method. In the first step, data envelopment analysis (DEA) was applied to estimate technical, pure technical and scale efficiency. In the second step, Tobit regression was used to identify factors affecting technical efficiency. The results showed that rice producers in southwest of Niger could reduce their inputs by 52% and still produce the same level of rice output. The Tobit regression showed that factors, such as farm size, experience in rice farming, membership of cooperative, main occupation and land ownership had a direct impact on technical efficiency.     

限水灌溉对冬小麦产量和水分生产效率的影响

１９９１～１９９３年在临汾市乔李村粮田３队进行冬小麦限水灌溉试验,提出减少灌溉次数（即灌溉量）,只在关键时期进行灌溉,就可使冬小麦节水与增产的目标同时实现。冬小麦灌溉量减少３３．０％～６６．７％,产量只减少６．３％～１２．３％,灌溉水生产效率提高３３．３％～１２７．８％。因此,根据试验结果和生产实践,临汾地区限水灌溉制度应为：在正常年份,一水条件下,浇足冬水;二水条件下浇好越冬水和浇足拔节水;存充足灌溉条件时要采取限水灌溉,节约水资源,应浇好越冬水,浇足拔节水,少浇孕穗水,小麦亩产可达到４００ｋｇ以上。     

灌水时期对小麦产量及水分利用效率的影响

采用裂区设计,研究了不同灌水时期对小麦产量和水分利用效率的影响。结果表明,冬前限量灌水塌实了土壤,促进了小麦冬前分蘖和次生根喷发,提高了成穗数,从而提高了产量;配合孕穗期增量灌水小麦产量最高、水分利用效率最高;配合拔节期增量灌水产量和水分利用效率均次之,且二者间差异不显著。     

Technologies for Efficient Use of Irrigation Water and Energy in China

While the shortage of water and energy is a well-recognized worldwide natural resources issue, little attention has been given to irrigation energy efficiency. In this paper, we examine the potential energy savings that can be achieved by implementing improved irrigation technologies in China. The use of improved irrigation management measures such as a flow meter, irrigation scheduling, and/or regular maintenance and upgrades, typically reduces the amount of water pumped over the course of a growing season. The total energy saved by applying these improved measures could reach 20%, as compared with traditional irrigation methods. Two methods of irrigation water conveyance by traditional earth canal and low pressure pipeline irrigation (LPPI) were also evaluated. Our study indicated that LPPI could save 6.48×109 kWh yr-1 when applied to 11 Chinese provinces. Also, the CO 2 emission was reduced by 6.72 metric tons per year. Among these 11 surveyed provinces, the energy saving potential for two provinces, Hebei and Shandong, could reach 1.45×109 kWh yr-1. Using LPPI, potential energy saved and CO 2 emissions reduced in the other 20 Chinese provinces were estimated at about 2.97×109 kWh yr-1 and 2.69 metric tons per year, respectively. The energy saving potential for Heilongjiang, a major agriculture province, could reach 1.77×109 kWh yr-1, which is the largest in all provinces. If LPPI is applied to the entire country, average annual energy saving of more than 9 billion kWh and average annual CO 2 emission reduction of more than 9.0 metric tons could be realized. Rice is one of the largest users of the world’s fresh water resources. Compared with continuous flooding irrigation, intermittent irrigation (ITI) can improve yield and water-use efficiency in paddy fields. The total increments of net output energy and yield by ITI in paddy fields across China could reach 2.5×1016 calories and 107 tons, respectively. So far only a small part of agricultural land in China has adopted water and energy saving technologies. Therefore, potential water and energy savings in China by adapting improved irrigation technology could be significant and should be carefully studied and applied.     

西北内陆旱区不同沟灌水肥对甜瓜水分利用效率和品质的影响

 【目的】甜瓜是西北内陆旱区的一种主要经济作物,探讨不同沟灌水肥对甜瓜水分利用效率(WUE)和品质的影响,提出适合该地区的甜瓜水肥高效利用技术模式。【方法】于2008和2009年在甘肃武威中国农业大学石羊河流域农业与生态节水试验站开展了连续两年的田间试验,在膨果期分别设置了3个灌水下限水平：65%—70%、55%—60%、45%—50%的田间持水量(FC);施肥量设置为：160、120、80 kgN?hm-2和无肥对照处理;灌溉方式为常规沟灌和隔沟灌。【结果】膨果期适度水分亏缺有利于提高甜瓜的水分利用效率,并在一定程度上改善其品质;相同施肥量条件下,灌水量下限为55%—60% FC处理其WUE、总可溶性固形物(TSS)和Vc含量普遍高于灌水量下限为65%—70% FC处理的结果;相同水分条件下,施肥量为120 kgN?hm-2处理其产量、WUE、TSS和Vc含量均高于施肥量为160 kgN?hm-2和施肥量为80 kgN?hm-2处理的结果。隔沟灌处理的WUE比常规沟灌高4.5%—10.6%。【结论】适合于该地区的甜瓜水肥组合模式为膨果期灌水下限为55%—60%FC和全生育期施氮量为120 kgN?hm-2。     

嫁接和自根黄瓜灌溉水分配和水分利用效率研究

研究了常规灌溉条件下,日光温室冬春茬和秋冬茬生产中,嫁接和自根黄瓜(Cucumis sativus L.)灌溉水分配状况和水分利用效率,旨在为制定合理的农艺节水措施提供理论依据。结果表明,两茬口试验中灌溉水分配量顺序均为土壤渗漏>植株蒸腾>土壤蒸发>土层贮水。其中,冬春茬灌溉水的分配比例为土壤渗漏44.3%、植株蒸腾35.4%、土壤蒸发15.7%、土层贮水4.6%;秋冬茬灌溉水分配比例为土壤渗漏49.6%、植株蒸腾29.7%、土壤蒸发13.9%、土层贮水6.8%。受根系分布状况和温室光温条件的影响,冬春茬土壤渗漏的比例低于秋冬茬,植株蒸腾与土壤蒸发的比例高于秋冬茬。冬春茬和秋冬茬嫁接黄瓜与自根黄瓜相比,土壤渗漏量分别低8.4%和3.4%,土壤蒸发量分别低12.0%和1.0%,蒸腾量分别高15.3%和4.0%;两茬口嫁接黄瓜的水分利用效率均显著高于自根黄瓜,因此嫁接是一种有效的节水措施。     

传统灌溉条件下水肥滞留效益研究

研究了径流灌溉时不同作物样地对水肥的滞留效益。结果表明,4种作物对水肥的滞留效果呈现出相似性,在9 m之前滞留效益十分显著,9 m之后,滞留效益呈现出明显的下降趋势。在此基础上得出滞留率拟合方程,4种作物的拟合函数均为对数函数,该拟合函数可以将4种作物的滞留率数量化,并为相关研究提供借鉴。     

灌溉频率对棉花干物质积累及水分利用效率的影响

【目的】研究滴灌条件下不同灌溉频率对棉花生长及产量的影响。【方法】在大田灌溉定额(4 650 m³/hm²)下,设置5个灌水频率(3、6、9、12和15 d/次,其中6 d/次为CK),分析灌溉频率对棉花生长发育过程中干物质积累及分配、产量的影响。【结果】高灌溉频率(3 d/次)干物质积累量较大,同化物向生殖器官的分配率较高,开花结铃数也较高,有利于提高籽棉产量和水分利用效率。【结论】在4 650 m³/hm²常规灌溉定额下,3 d/次的高频灌溉能够提高棉花的干物质积累量,有利于籽棉产量和水分利用效率的提高。     

不同灌溉方式对晚造超级稻产量及水分利用效率的影响

以超级稻品种特优航1号、天丰优998为试验材料,于2008年、2009年晚造进行大田栽培,比较了其在3种不同灌溉方式下的农艺性状、产量及水分利用效率。结果表明:控水灌溉②超级稻品种的株高、剑叶面积、产量及水分利用效率最高;灌溉量最小。特优航1号,天丰优998在2008年和2009年分别节水33.25%、31.99%和33.43%、36.55%。控水灌溉②是桂南稻作区晚造超级稻较为适宜的灌溉方式。     

Fruit Yield and Quality,and Irrigation Water Use Efficiency of Summer Squash Drip-Irrigated with Different Irrigation Quantities in a Semi-Arid Agricultural Area

Fruit yield, yield components, fruit mineral content, total phenolic content, antioxidant activity and irrigation water use efficiency (IWUE) of summer squash responses to different irrigation quantities were evaluated with a field study. Irrigations were done when the total evaporated water from a Class A pan was about 30 mm. Different irrigation quantities were adjusted using three different plant-pan coefficients (Kcp, 100% (Kcp1), 85% (Kcp2) and 70% (Kcp3)). Results indicated that lower irrigation quantities provided statistically lower yield and yield components. The highest seasonal fruit yield (80.0 t ha⁻¹) was determined in the Kcp1 treatment, which applied the highest volume of irrigation water (452.9 mm). The highest early fruit yield, average fruit weight and fruit diameter, length and number per plant were also determined in the Kcp1 treatment, with values of 7.25 t ha⁻¹, 264.1 g, 5.49 cm, 19.95 cm and 10.92, respectively. Although the IWUE value was the highest in the Kcp1 treatment (176.6 kg ha⁻¹ mm⁻¹), it was statistically similar to the value for Kcp3 treatment (157.1 kg ha⁻¹ mm⁻¹). Total phenolic content and antioxidant activity of fruits was higher in the Kcp1 (44.27 μg gallic acid equivalents (GAE) mg⁻¹ fresh sample) and in the Kcp2 (84.75%) treatments, respectively. Major (Na, N, P, K, Ca, Mg and S) and trace (Fe, Cu, Mn, Zn and B) mineral contents of squash fruits were the highest in the Kcp2 treatment, with the exception of P, Ca and Cu. Mineral contents and total phenolic content were significantly affected by irrigation quantities, but antioxidant activity was not affected. It can be concluded that the Kcp1 treatment was the most suitable for achieving higher yield and IWUE. However, the Kcp2 treatment will be the most suitable due to the high fruit quality and relatively high yield in water shortage conditions.