对中兽药质量标准及质量控制的思考

探讨了中兽药质量标准及其质量控制存在的问题及原因,并论述了它们的发展前景。     

Open geospatial technology standards and their potential in plant pest risk management—GPS-enabled mobile phones utilising open geospatial technology standards Web Feature Service Transactions support the fighting of fire blight in Norway

The threat posed by invasive alien species to global crop production and biodiversity is recognized as one of the major drivers of global change today. Here we report on a successful implementation and operational use of new technology to support risk- and crisis management in the case of fighting an invasive plant disease. The open geospatial standards Web Feature Service Transaction (WFS-T) was implemented in software for GPS-enabled mobile phones communicating with a GeoServer backend in order to track down and eradicate disease outbreaks and susceptible host plants. This new technology offering georeferenced events online from field provides new possibilities for real time action in risk and crisis management.     

Observations on relationships between regeneration stocking and yield

Explicit linkages between various levels of regeneration stocking and yield have been assumed for most of the last century but have rarely been quantified. There are many variations in methodology for measuring stocking, but the implications for yield prediction of employing different methods are poorly understood. For the purpose of yield prediction, contrasts are drawn here between several variations on two basic regeneration survey methodologies: stocked quadrats and the British Columbia Ministry of Forests’ well-spaced survey system. Curve shape and dispersion for the relationships between survey summary statistics and yield varied dramatically by varying survey parameters such as quadrat size and the maximum number of tallied well-spaced trees. Also of importance is the stand height at which yield is assessed. Finally, it is critical to standardize survey parameters so that summary statistics are consistently comparable.     

农村宅基地用地类型划分与用地标准

如何制定出一套符合大多数农户生产、生活以及发展需要的宅基地标准,是当前开展新农村建设、土地增减挂钩和土地整治规划工作的迫切要求。该文首先在对调查数据进行统计分析的基础上,采用K-Means Cluster聚类分析方法将170户被调查农户分成3类;其次,在农户类型划分的基础上,参照国家和省级各种技术规范,根据被调查农户的宅基地用途和自身的生产经营状况分析出各类型农村宅基地用地标准。通过聚类分析可将被调查农户分成务工型、半工半农型和务农型3种类型;并分析得出这3种类型农户的宅基地用地标准分别为42～45m2、48～50m2和52～55m2。该文尝试找到符合当地实际的农村宅基地用地标准,并为同类型地区城乡建设用地空间规模和空间布局的确定提供参考。     

世界主要农业发达地区农产品追溯体系发展现状

确保安全和提升品质是现阶段世界范围内农产品的两大主题。基于现代信息科技及物联网技术的农产品追溯机制主要涉及两方面功用,一方面通过将供应链的相关信息透明化,最大程度降低生产者和消费者之间的信息不对称;另一方面通过在农产品供应链上下游实现追踪和溯源两大功能,推进农产品安全责任制,迎合了人们对农产品安全和品质的需求,引起了世界范围内的广泛重视,纷纷予以推动和实施。该文从追溯法律与法规、标准与规范、推动与实施3个层面阐述了欧美、日韩及台湾等世界主要农业发达地区农产品追溯体系的推进和最新发展情况,在列举典型追溯系统实例的基础上对比分析并总结了各自发展的特点,指出综合与精简是农产品追溯体系的发展方向,最后从机构、立法、标准、实施、验证等多个角度对中国农产品追溯体系的进一步发展、推广与深化提出建议,以期真正发挥追溯体系效用、守护国人健康。     

氰戊菊酯对照品的质量检测及赋值

为研制兽用氰戊菊酯国家对照品。取氰戊菊酯原油精制得氰戊菊酯原料,经质量检查,最大紫外吸收波长为277 nm、熔点为53-54℃、水分为0.02%,用正相和反相两种高效液相色谱法测得纯度为99.8%,按质量平衡法进行含量赋值为99.8%,不确定度为±0.1%。     

我国水环境污染的防治措施

探讨了我国水环境污染的防治措施,包括技术防治措施和法律规范对策等.     

Optimum Nutrient Concentrations and CND Scores of Mature White Spruce Determined Using a Boundary-Line Approach and Spatial Variation of Tree Growth and Nutrition

ABSTRACT

Standards of optimum nutrition are not readily available for mature trees of the Canadian boreal forest. The objective of this study was to determine foliar nutritional standards for white spruce for all major nutrients [nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), and manganese (Mn)] using critical values (CVA) and compositional nutrient diagnosis (CND). Trees were sampled at two locations in Ontario and Quebec to cover a gradient of soil fertility levels. A boundary-line approach was used in combination with quadratic regression models to estimate the relationship between growth and foliar-nutrient concentrations or CND scores when free of the effects of interacting environmental factors. White spruce optimum nutrition ranges were computed from significant relationships (P ≤ 0.10) for N, P, K, Ca, and Mn concentrations and for N, P, and K CND scores. Optimum concentrations for first-year needles were 12.3, 1.9, 7.3, 6.5, and 0.39 mg g^?1 for N, P, K Ca, and Mn, respectively, whereas optimum CND scores were 0.17, ?1.65, ?0.40, and ?0.30 for N, P, K, and Ca, respectively. Samples from a broader range of environmental conditions will be required in order to establish standards for all major nutrients and to ascertain toxicity levels of most nutrients.     

An examination of the total analysis of major elements in soil samples

Recently conventional chemical analyses were mostly replaced by instrumental analysis. Although results from both methods were examined in details after the samples had been solubilized or extracted by appropriate techniques, the solubilization method was considerably altered so as to be convenient for the following analysis. In atomic absorption spectrophotometry (AAS), for example, fusion technique was mostly inadequate because of the higher salts concentration in the obtained solution. The use of H₂SO₄ must also be avoided in acid digestion for SO₄ ^2- precipitates with Sr²⁺ or La³⁺ which must be added to eliminate interferences in the succeeding procedure. Therefore, it is essential to consider the whole scheme including sample treatments to evaluate the suitability of instrumental analysis. In this experiment, the suitability of the methods which have been employed in our laboratory was examined by analyzing 9 rock standards.     

Quantitative assessment of tuber contamination by pectolytic erwinia and its possible use in the prediction and control of blackleg

Summary A Most Probable Number Technique based on the use of carbohydrate-free McConkey broth and crystal violet pectate agar for the quantification of tuber-borne pectolytic erwinia has been developed. The population of the organisms on naturally contaminated tubers has been shown to be log-normally distributed. The possibility of using tuber contamination and standards for tuber quality for the prediction and control of blackleg is explored.