Quantifiable Technique for Product Definition

近年来，我国水果种植业发展十分迅速，总产量跃居世界第一位。但是，一种奇怪的现象一直困扰着水果市场，一方面农民卖果难；另一方面水果出口数量发展缓慢，国内市场终端的水果质量也不尽人意。除了某些水果品种过时、栽培技术有待改进外，另一个主要原因就是水果物流过程中存在着诸多问题。提高我国水果在国际市场的竞争能力，改善我国水果市场终端的商品品质，减少水果采后物流中的损耗是摆在水果研究人员面前亟待解决的问题。本文将对几种有代表性水果的物流现状进行概述，并就目前水果物流中存在的问题进行分析。１红富士苹果１．１主…     

The Humus Content and Soil Biological Properties as a Function of Organic and Mineral Fertilization

There is a growing recognition for the need to develop sensitive indicators of soil quality that reflect the effects of land management on soil and assist land users in promoting sustainability of agro-ecosystems. Three soil enzymes (dehydrogenase, phosphatase and invertase) microbial biomass as biological variables and soil organic matter content (SOM) were investigated relative to fertilization and soil fertility (estimated by crop yield) at a long-term fertilization trial (Keszthely, Hungary). 0-34.7-69.4-104.1t farmyard manure (FYM) ha m 1 5 yr m 1 and the corresponding amount of mineral fertilizers (NPK) were applied in two different crop rotation systems. There were four straw and/or stalk incorporating treatments in the second crop rotation 'B'. Enzyme activities, microbial biomass and the amount of SOM were generally higher in the fertilized soils than in the unfertilized soils. The type of amendments (mineral, FYM or mixed) had significant effects only on the amount of SOM. The correlations among the biological variables and the crop yield were generally low (r < 0.250. The differences in field management resulted only in the invertase activity.     

仿形弹性镇压辊设计与试验

针对保护性耕作条件下与大豆耕播机配套的镇压辊压实土壤不均匀、相关耕播机具纵向尺寸过长的问题,设计了一种仿形弹性镇压辊,采用弹性辐条结构,通过理论分析确定了镇压辊的主要结构参数:直径D=450 mm,宽度B=210 mm,弹性辐条数量n=12。利用ADAMS软件对镇压辊进行运动仿真,同时进行土槽试验,采用L9(34)正交试验,在土壤干基含水率为20%时,考察了仿形弹性镇压辊的弹簧刚度k、载荷F、作业速度v和土壤坚实度P对其镇压力波动的影响。通过ADAMS运动仿真,找到了各因素的最佳取值范围;通过正交试验,得到了各因素的主次顺序:载荷、弹簧刚度、土壤坚实度、作业速度,最优组合为载荷800 N,弹簧刚度5 N/mm,土壤坚实度15 k Pa,作业速度0.5 m/s,模拟仿真的结果与试验结果吻合很好。通过对比试验,得到仿形弹性镇压辊在垄台表面有一定倾角的情况下能更好地保证镇压的均匀性。     

Using behavioral landscape ecology to predict species’ responses to land-use and climate change

Climate change and habitat destruction are widely recognized as major threats to species’ survival. As a result of these anthropogenic impacts, species are often forced into novel landscapes where their persistence is difficult to predict. Knowledge of how individuals move or disperse through the landscape, choose habitat in which to settle, and produce offspring which survive to repeat the process can greatly improve our ability to predict species’ persistence. The field of behavioral landscape ecology uses a strong theoretical base to explore, often experimentally, how the behavior of a particular species is affected by heterogeneous and rapidly changing landscapes and can offer valuable insight for managing species in the face of human-induced environmental changes. When interpreted by modelers, results of landscape-level behavioral experiments can be quantified for use in predictive models. To this end, we summarize the methods and results of research using direct experimental manipulation techniques broken into the following categories: translocations, playback experiments, food resource manipulations, manipulations of reproductive success, direct manipulations of the landscape, and manipulations of predation risk. We review and place in a theoretical framework the results from this emerging body of research regarding how organisms move in and respond to different types of landscapes, both natural and human-altered. We go onto highlight the potential of each experimental method to quantify different processes, which may be useful when interpreted by modelers attempting to parameterize predictive models. Finally, we suggest future directions for experimental research that will allow for greater integration of behavioral landscape ecology and predictive modeling.     

The Study on the Analysis Method of the Experiment Result of the Partition Compares Method Designing

讨论了间比法设计试验结果常规分析方法所存在的问题,提出了理论对照的概念及计算公式。采用试验结果与理论对照(CK’)直接比较的分析方法,可以有效解决常规分析方法存在的误判问题。     

倾斜圆台型玉米精密排种器种子破损试验

针对机械式精密排种器伤种率高的问题,提出了一种基于丸粒化玉米种子的精密排种器.以排种轴转速、型孔直径、动盘锥角为因素,种子破损率为指标,运用二次回归正交旋转安排试验,建立了种子破损率与各影响因素之间的回归数学模型.通过Design-Expert 7.1软件对试验参数进行优化,确定排种轴转速13.2 r/min、型孔直径16 mm、动盘锥角26.5°为最佳参数组合,此时种子破损率为0.65％.验证试验表明该组合下试验误差较小.     

玉米水平圆盘精密排种器种子破损试验

从水平圆盘精密排种器的工作原理出发，对影响玉米种子破损的因素进行了正交试验，分析了引起种子破损的原因。结果表明，影响种子破损的主要因素是动定盘间隙和推种器弹簧压力。     

双层覆盖温室地下蓄热系统保温效果试验

针对温室加温能耗大的突出问题，设计了双层覆盖温室地下蓄热系统。测试了冬季夜间保温时温室内外温度、湿度，计算了达到同样环境温度时燃煤热水锅炉加温所需能耗及燃料成本。结果表明，在冬季白昼为晴天、多云、阴天时，双层覆盖温室地下蓄热系统蓄热后，夜间保温时温室内温度分别高于外界温度5．1～9．8℃、4．8～6．9℃、4．2～6.4℃，室内外平均温差分别为6．9℃、5．4℃、5．3℃，其能耗费用低于燃煤热水锅炉加温费用，系统具有良好的保温性能，节能效果明显。     

Soil Organic Matter Content and Quality in Polyfactorial Field Experiments

The polyfactorial long-term field experiments founded in 1979 exist in four different sites till the present time. The experimental design and selected variants have been described in our previous paper (Lipavsky et al. 2002). Besides of the organic carbon and nitrogen contents in soil, dry matter of the main and second products, nitrogen uptake by the main and second products presented in our previous paper (Lipavsky et al, 2002), hot water soluble carbon (C hwl ), humic substances, e.g. humic and fulvic acids have been determined in soil samples taken in autumn each year from six selected variants of organic and mineral fertilisation. The results of the hot water soluble carbon content and humic and fulvic acids contents in the air dried soil samples have been evaluated in this paper. It was shown that humic substances are rather conservative and site specific soil properties that are not much affected by the cropping and fertilisation systems. Hot water soluble carbon, on the other hand, seems to be a dynamic part of the soil organic matter.     

Effects of Long-term Organic and Mineral N-fertilisation on Soil Microarthropods in Berlin (Germany), Madrid (Spain) and Tartu (Estonia)

Soil micro-arthropods play an important role in the nutrient cycle of agro-ecosystems and are considered to have a strong impact on microbial activity. The occurance of soil microarthropods was investigated in the International Organic Long-Term Field Experiment (IOSDV). The investigation took place in the experimental fields of Berlin/Germany, Madrid/Spain and Tartu/Estonia. Field plots "without organic fertisation", "farmyard manure" and "straw-beet-leaves-green manure" without mineral N-fertilisation and with 120kg/ha mineral N-fertilisation respectively have been investigated. Data shows that the effects of organic manure and mineral N-fertilisation are considerably influenced by specific site characteristics. The highest abundances were found in the experimental field of Madrid. In the two nothern sites soil microarthropods were found only in very low quantities. Data indicates that not only organic manure but also mineral N-fertilisation may influence the abundance of soil micro-arthropods positively.