Productivity and profitability of multistrata organic versus conventional coffee farms in Costa Rica

In areas where traditional multistrata coffee systems have been transformed to systems with patchy or no shade at all, often dependent on high chemical inputs, ecological and socioeconomic degradation has become an increasing issue. During the 1990s, rising environmental and health concerns have promoted the interest in organic production systems and their environmental services for natural resource conservation. This study compared productivity, profitability, producer-defined constraints, and goals and research priorities between ten individually paired organic and conventional coffee farms in Costa Rica. Although five of the organic farms matched or exceeded the production of their conventional counterparts, the three-year mean yield of the organic farms as a group was 22% lower than that of the conventional farms. However, excluding organic certification costs, mean variable costs and net income (NI) were similar for both groups, mainly because organic price premiums received by the farmers compensated for lower yields. If current organic certification costs are included, the price premiums paid to organic producers would have to increase to 38% in order to equal the NI from conventional coffee. Conventional farmers indentified low and unstable prices as the main constraints to sustained production and stated further intensification of production as their main goal. In contrast, the key issues for future development of the organic group centered on farm diversification, agroecological self-sufficiency, and agronomic practices that permit organic farm management. This revised version was published online in June 2006 with corrections to the Cover Date.     

Influence of Ammoniacal Copper Quaternary treatments on mechanical properties of blue-stained Lodgepole Pine wood

Three concentrations （2.8%, 2.0%, 1.2%） of Ammoniacal Copper Quaternary （ACQ） was selected to treat Lodgepole pine wood for evaluating ACQ treatment on mechanical properties of blue-stained wood. The bending modules of elasticity （MOE）, modules of rupture （MOR）, toughness and shearing strength parallel to grain on tangential surface, are tested according to the criteria GB1927-1943-91. Non-treated sample were also tested according to the same procedure. The results showed that the three groups specimen impregnated by different concentrations of ACQ solution met the AWPA standard 2003 of America （UC4A 6.4g/cm^3）. There were significant difference of toughness between treated wood and non-treated wood （p=0.01）, but there were no statistically significant differences among three concentrations in terms of toughness, and toughness of treated wood was approximately 20% lower than non-treated. MOR, MOE as well as sheafing strength parallel to grain were found to be not significantly different between treated wood and non-treated one, and there were no statistically significant difference among three concentrations of ACQ too. Toughness, MOR, MOE and sheafing strength parallel to grain increased with decrease of concentration of ACQ, but they were hardly affected by ACQ preservatives.     

Technical efficiency in the spice based agroforestry sector in Matale district, Sri Lanka

Spices constitute an important sub-sector of the economy of Sri Lanka. Most perennial spices are cultivated in agroforestry types of farming systems. A field survey was conducted covering 127 agroforestry farmers in six divisional secretariats in Matale district during the period of October to December 2002. Technical efficiency of spice based agroforestry systems was estimated in order to identify the potential increase in production without incurring additional costs for farm inputs. The factors affecting technical efficiency and constraints and potential of the agroforestry system were also investigated. According to a stochastic frontier production function using a Cobb–Douglas model, hired labour, organic fertilizer, inorganic fertilizer, land size, and soil conservation measures showed significant positive effects on the agroforestry production. The mean technical efficiency of the spice based agroforestry systems was 84.32%. According to the inefficiency model the efficiency increased significantly as a result of farm visits by extension officers, participation in farmer training, less sloping lands, more experience, and higher diversity of the agroforestry system. Technical efficiency decreased, however, with higher education level of the farmer and with higher off-farm income. Unsustainability of the agroforestry system is seen as a result of a␣range of constraints related to productivity, market, technology and institutions.     

农户家庭经营问题研究——对邢台县浆水镇农户抽样调查材料的分析

本文应用数理统计方法对邢台县浆水镇9村265户样本资料进行了系统分析。指出农户家庭经营是我国农村普遍存在的基本经营形式。这一新生事物完全适应现阶段农村生产力发展水平,其收入已成为农民收入的主要来源。近年来,农民收入虽有大幅度提高,但水平仍然很低,农户间收入差距也在不断扩大,山区农村经济仍在一个低水平上运行。本文还对影响农民收入水平的相关因素和农户收支结构进行了分析,并有针对性地提出改善家庭经营管理的建议。最后,对加强农户家庭经营方面的研究与领导也提出具体意见。     

Application of modal analysis by transfer function to nondestructive testing of wood II: modulus of elasticity evaluation of sections of differing quality in a wooden beam by the curvature of the flexural vibration wave

 The shape of the flexural vibration wave of wooden beams at the first mode was detected using the transfer function. The dynamic modulus of elasticity (MOE) of beam sections of differing quality was estimated from the ratio of the curvature of the wave shape in this section to that of a clear beam. The results were as follows: (1) If a section with a lower dynamic MOE was introduced into a clear wooden beam, the curvature of the wave shape in that section became higher. (2) The ratio of the MOE and the reciprocal of the curvature ratio were highly correlated. (3) The MOE of a defect could be estimated, and the position of the defect could be determined accurately by examining the curvature of the flexural vibration wave shapes. Received: March 22, 2002 / Accepted: May 15, 2002 Part of this report was presented at the 50th Annual Meeting of the Japan Wood Research Society, Kyoto, April 2000. This article is translated from the Japanese version, which was published in Mokuzai Gakkaishi 47(5), 2001 Correspondence to:Y. Ishimaru     

Plant species diversity of homegardens of Cuba and its significance for household food supply

The cultivation of different plants in homegardens for self-sufficiency has a long tradition in Cuba, but knowledge about homegardens in Cuba is small. To analyse this more deeply, cultivated plants of 31 homegardens were surveyed in three villages in eastern Cuba in 2001. Two of the study villages were located in a humid area with an annual precipitation of about 2200 mm. The third village was situated in a semiarid area with about 450 mm precipitation. The plants studied in the homegardens included those for human consumption such as fruits, vegetables, tubers and cereals as well as spices and medicinal plants. In total, 101 different plant species were found with an average number of 18 to 24 species per homegarden for the three villages. A broad range of species was found in all villages, because irrigation is used under semiarid conditions, which lead to a relative high similarity in species composition between the villages. But, also differences due to the climatic situation became evident, particularly with the medicinal plants. In general, homegarden production provided a broad and diverse basis for self-sufficiency of the households. Although homegarden production showed to be only a small source of income, it is particularly important because of low-paid outside work and minimal food provision of the state.This revised version was published online in November 2005 with corrections to the Cover Date.     

Ⅰ-72杨人工林的投入产出及经济成熟龄

本文讨论了山东省沂南县沂河林场不同密度Ⅰ-72杨人工林的投入产出及经济成熟龄。投入分为一次性投入和每年投入。一次性的总投入量为2 33 1.00元/ha,其中整地占84％;平均年投入为253.21元/ha·a,其中追肥占74％。文中还计算了长期占用资金的复利。对各密度的年投入量、年生长量、年产值、年均净产值及其年动态进行了研究,同时做了林木的年均生长量和年均净产值数学模拟。杨树人工林在造林后第三年才能获得利润。数量成熟龄为6～10年,年均最高生长量可达25.252 1 m~3/ha·a。经济成熟龄为6～7年,年均最高净产值可达6 110.52元/ha·a。杨树人工林的数量成熟龄与经济成熟龄主要受密度及投入成本的影响。     

竹片覆面胶合板的初步研究

本文研究了以竹片为外层材料、多层杨木单板为芯层材料的复合胶合板的结构和力学性能，分析了板坯结构形式、纵向纵片厚度、单板层数及板坯压缩率与产品机械强度之间的关系。初步研究结果表明，板坯结构形式对产品的静载荷抗弯曲性能影响显著；在试验范围内，纵向竹片厚度为３．５－５．０ｍｍ、板坯压缩率在２３％左右时，竹片覆盖面杨木胶合板的综合力学性能比较理想。     

Agroforestry in the interior highlands

The USDA Agricultural Research Service, headquartered at the South Central Family Farm Research Center, Booneville, Arkansas, recently initiated an agroforestry research program for the interior highlands and the southeastern United States. The purpose of the agroforestry program is to develop a research and technology transfer program in agroforestry that will provide additional alternative income opportunities for family farms of this region. The objectives of the program are: 1) to develop new information on the establishment, maintenance, and utilization of conifer and hardwood tree stands in open pastures, 2) to develop new knowledge in multiple-use management and their environmental impacts, and 3) to facilitate multidisciplinary networks and partnerships of farmers, technical specialists, scientists, and managers for accomplishing agroforestry research and technology transfer.     

Impact of agroforestry intervention on farm income under the subsistence farming system of the middle hills, Nepal

Practices that minimize the rate of soil degradation, increase crop yields and raise farm income are key to sustaining agricultural productivity in the hills of Nepal. The use of farmland is undergoing rapid changes in response to increasing population pressure, deforestation and subsistence needs. Against this background, this study examined the impact of an agroforestry intervention project on farm income based on a sample of subsistence farm households in Dhadhing district. The project was implemented by Nepal Agroforestry Foundation in 1993/94 to increase fodder production through the promotion of agroforestry. A total of 223 households (82 with project and 141 without project) were interviewed during May–October 1998 to collect information on production and agroforestrys' impact on farm income. The benefit-cost analysis showed that the agricultural system including agroforestry was more profitable than the conventional one. The results also showed that the introduction of mulberry trees for sericulture could further enhance the profitability of an agroforestry-based system. Thus, agroforestry has great potential for enhancing food production and farmers' economic conditions in a sustainable manner through its positive contributions to household income.This revised version was published online in November 2005 with corrections to the Cover Date.