云南草业科技的研究方向和发展趋势

从云南的自然条件和社会发展需要出发,分析总结了云南草业科技今后的研究方向和发展趋势,主要是牧草种质资源的研究,牧草育种,牧草在种植业结构中的研究及应用,草地畜牧业可持续发展的研究和应用,生态环境治理,草坪业发展中的新品种、新技术的研究和应用等。     

适应机械化收获的田间油菜植株特性研究

油菜机械化收获过程出现的高损失率制约了油菜生产的发展,单纯从农机方面进行研究难以解决。该文从农机农艺相结合出发,对田间油菜植株特性进行测试研究。测试大田植株整体表现特性及不同密度下植株茎秆物理特性的田间表现,并在不同成熟度和催熟剂喷施情形下对油菜角果拉断力进行测试,获得了田间植株特性基础数据。结果表明适宜的种植密度有利于机械化收获作业,催熟剂的喷施对机收作业性能影响不大。研究获得了直播油菜的田间植株表现特征,同时为油菜机收配套农艺要求提供理论研究基础和参考依据。     

Opportunity costs: Who really pays for conservation?

Designing conservation areas entails costs that, if considered explicitly, can be minimized while still achieving conservation targets. Here we focus on opportunity costs which measure forgone benefits from alternative land uses. Conservation planning studies often use partial estimates of costs, but the extent to which these result in actual efficiencies has not been demonstrated. Our study partitions land costs into three distinct opportunity costs to smallholder agriculture, soybean agriculture and ranching. We demonstrate that opportunity costs to single stakeholder groups can be inaccurate measures of true opportunity costs and can inadvertently shift conservation costs to affect groups of stakeholders disproportionately. Additionally, we examine how spatial correlations between costs as well as target size affect the performance of opportunity costs to single stakeholder groups as surrogate measures of true opportunity costs. We conclude that planning with opportunity costs to single stakeholder groups can result in cost burdens to other groups that could undermine the long-term success of conservation. Thus, an understanding of the spatial distributions of opportunity costs that are disaggregated to groups of stakeholders is necessary to make informed decisions about priority conservation areas.     

Nutrient Availability Response to Sulfur Amendment in Histosols having Variable Calcium Carbonates

High soil pH and excessive calcium carbonate (CaCO₃) in the Everglades Agricultural Area of south Florida reduce the availability of phosphorus and micronutrients to crops. Sulfur (S) amendment is recommended to reduce soil pH and enhance nutrient supply. The study’s objective was to determine the sulfur amendment effectiveness on soil pH and nutrient availability in organic soil as CaCO₃ content increases in soil. An experiment of four S rates (0, 90,224, and 448 kg ha^?1) and three added CaCO₃ (0%, 12.5%, and 50% by volume) in organic soil was established. Sulfur application had limited effects on soil pH reduction as CaCO₃ level increased and therefore failed to enhance nutrient availability; however, it increased sulfate concentration in soils, which could be at risk for export from the field. Unexpected increases in manganese concentration with added CaCO₃ was associated with reducing conditions due to increased soil bulk density, which changed the soil physical properties.     

不同剂型农作物种衣剂研究

本文介绍了农作物种衣剂的剂型种类，确定了不同作物种衣剂中活性组分、农药的种类及使用量，筛选出了非活性组分的种类及配制比例，研制出了不同剂型的农作物种衣剂的基本配方。     

县域农机化技术推广工作探讨

在新的形势下,县域农机推广部门肩负着认真做好技术推广工作的重任,农机推广部门应该明确目标,履行职责,抓住重点,强化自身素质,更快更好地做好农机化普及工作.     

西北农业高校图书馆信息化建设

本文从信息资源建设、信息化人力资源建设、信息资源共享体系等几个方面，探讨西北农业高校图书馆信息化建设。     

Adoption of improved crop varieties by involving farmers in the e-wallet program in Nigeria

The amount of improved seed used in Nigeria is extremely low. Overall, only 5–10% of cultivated land is planted with improved seeds, and about 10% of rural farmers use improved varieties. The objective of this investigation was to identify determinants of adoption of improved seed by farmers not participating in and those participating in the federal government’s e-wallet program in Nigeria. We determined the impact of the e-wallet program on adoption of improved seed in rural areas. A total of 1200 rural farmers were sampled across six geopolitical zones of Nigeria. Results from the use of a bivariate probit model indicated that the e-wallet program continued to become increasingly popular among rural farmers; and that farmers’ literacy, ownership of a mobile phone, value output, mobile network coverage, power for charging phone batteries and contact with extension agents were the positive determinants of farmer participation in the e-wallet program. Cultural obstacles to married women, growers’ age, and increased distance to registration and input collection centers reduced farmers’ tendency to participate in the e-wallet program. The results also showed that rural farmers depended on the e-wallet program for increased use and adoption of improved seed in Nigeria, to boost food security in sub-Saharan Africa. The results suggested the need for an improved e-wallet model by lessening constraints mostly associated with rural information and communication infrastructure, and distance to the registration and input collection centers.     

农业机械化是农业巨系统的子系统

农业机械化不仅是技术发展过程,而且是经济、社会、文化发展过程,是客观发展的动态的过程。本文分析了农业现代化的系统性和选择性,提出将农艺、农机和自然、资源、环境等条件综合分析,对各种子系统全面研究,并重视定位分析,因地制宜地科学发展现代农业。      

Degradation behaviour of poly(lactic acid) films and fibres in soil under Mediterranean field conditions and laboratory simulations testing

Long-term degradation/disintegration behaviour, indicative of the biodegradation in soil behaviour of poly(lactic acid) films and fibres, was studied in natural Mediterranean soil environment during an eleven-month trial in the experimental field. In parallel, simulated soil burial experiments were carried out under controlled laboratory conditions. The degradation/disintegration behaviour of PLA was analysed using visual inspection, mechanical testing, DSC and FTIR analysis. The influence of the thickness and the type of the materials (film vs. fibre) on disintegration was investigated under the given mild conditions. For comparison purposes, degradation/disintegration of PLA film was also studied under low temperature composting conditions (house composting). During long-term exposure under natural soil environment dominated by complex and uncontrolled biotic-abiotic conditions and Mediterranean climatic conditions and under house composting conditions, PLA film samples of different thicknesses were partially, to a rather low degree, degraded mechanically or slightly disintegrated. The results showed that degradation behaviour of bio-based polymers like poly(lactic acid) in a real soil environment is a complex phenomenon, following different patterns regarding morphological changes.