Our educational institution has 50 years in the service of veterinary medicine

The paper gives an overview of the history of the school of vet. med. technicians at the School of Veterinary medicine Hannover.     

The quantitative composition of the gastrointestinal flora in piglets during the first weeks of life. 1. The development of the gastrointestinal flora in naturally reared piglets]

Studies were conducted into the quantitative composition of the gastro-intestinal flora of 30 naturally raised piglets in four age groups. The gastro-intestinal tract was found to be "flooded" by Escherichia coli, Clostridium perfringens, micrococci, streptococci, proteus, and lactobacteria over the first hours after birth. Development of the intestinal flora was complete at the age of four days. The groups of germs recordable from naturally and artificially raised piglets were, basically, the same. Piglets, consequently, have no specific "lactoflora".     

牧场土壤含水率与坚实度空间变异与相关性分

利用土壤水分/圆锥指数复合测量装置,应用精细农作技术体系网格定点测量与GPS定位,在一块面积约1.27 hm2的草地上获取了土壤含水率与坚实度空间分布基础数据,并针对采样过程中出现的数据缺失,用偏最小二乘法对数据进行修补.然后运用克里格插值法进行数字化成图,并在此基础上分别对含水率与坚实度的空间变异性及两者的相关性做了分析.     

基于电磁阀的喷嘴直接注入式农药喷洒系统

设计了一种喷嘴直接注入式农药喷洒系统。通过与传统喷雾机械比较,简述了喷嘴直接注入式喷雾系统的结构和喷雾执行单元。为了实现农药定量注入,设计一种基于电磁原理的快速响应阀,并论述其工作原理和闭环控制方式。通过试验测试了喷雾执行单元的喷雾特性和喷杆组内各喷雾单元的一致性。结果表明在一定喷洒速率范围内,喷雾执行单元的喷水量和水压强存在多项式关系,农药注入量和PWM信号的高电平时间存在指数关系,其决定系数均高于0.9,并且同一喷杆组内6个喷雾单元的喷雾效果大体一致。     

Evaluation of a combined penetrometer for simultaneous measurement of penetration resistance and soil water content

A combined penetrometer is an appropriate tool to measure the soil cone resistance and the water‐content profile. As a relatively new technique, a combined capacitance‐penetrometer for the simultaneous measurement of cone index and soil water content was developed at the Department of Agricultural Engineering of Bonn University in 2002. The objective of this study was the evaluation of the effectiveness and applicability of the innovated penetrometer with a focus on three aspects: (1) A capacitance sensor with two electrode configurations was calibrated for silt loam, sandy loam, and sand. The calibration results show that both electrode configurations have sufficient water‐content sensitivity, but soil‐specific calibrations seem necessary. (2) Under laboratory conditions, the dynamic resolution and response of the capacitance‐penetrometer were validated, and its radius of influence was determined. (3) The field measurement results demonstrate that this measurement technique can be used to improve the interpretation quality of soil cone index data.     

基于激光反射的土壤表面粗糙度测量装置设计与试验

为了实时获取土壤表面粗糙度数据,设计了一种基于激光三角测距原理的土壤表面粗糙度专用测量装置.采用激光扫描测距仪测量微位移,其精度高、响应速度快,测距分辨力高达0.1 mm,显著提高了土壤表面粗糙度的测量精度;借助于光电编码盘和螺杆组合实现高精度扫描定位;PDA作为上位机,农田环境下具有方便携带,大容量存储数据和智能化实时处理功能等优点.     

Concept and feasibility study for the integrated evaluation of environmental monitoring data in forests

In the 1970s unexpected forest damages, called “new type of forest damage” or “forest decline”, were observed in Germany and other European countries. The Federal Republic of Germany and the German Federal States implemented a forest monitoring system in the early 1980s, in order to monitor and assess the forest condition. Due to the growing public awareness of possible adverse effects of air pollution on forests, in 1985 the ICP Forests was launched under the convention on long-range transboundary air pollution (CLRTAP) of the United Nations Economic Commission for Europe (UN-ECE). The German experience in forest monitoring was a base for the implementation of the European monitoring system. In 2001 the interdisciplinary case study “concept and feasibility study for the integrated evaluation of environmental monitoring data in forests”, funded by the German Federal Ministry of Education and Research, concentrated on in-depths evaluations of the German data of forest monitoring. The objectives of the study were: (a) a reliable assessment of the vitality and functioning of forest ecosystems, (b) the identification and quantification of factors influencing forest vitality, and (c) the clarification of cause-effect-relationships leading to leaf/needle loss. For these purposes additional data from external sources were acquired: climate and deposition, for selected level I plots tree growth data, as well as data on groundwater quality. The results show that in particular time series analysis (crown condition, tree growth, and tree ring analysis), in combination with climate and deposition are valuable and informative, as well as integrated evaluation of soil, tree nutrition and crown condition data. Methods to combine information from the extensive and the intensive monitoring, and to transfer process information to the large scale should be elaborated in future.

Zu Prekler’s „rationellem Baldwirth“

Ohne Zusammenfassung f. f?chf. Dberforftmeifter. f. bahr. Regierungs- und Forftrath von Mürzburg. f. preuk. Dberforftmeifter aus Breslau. f. f?chf. Dberforftmeifter. f. bahr. Regierungs- und Forftrath von Augsburg. f. bahr. Regierungs- und Forftrath aus Regensburg. Dberj?germeifter von Braunfchweig. f. bahr. Regierungs- und Forftrath aus München. f. f?chf. Dberf?rfter. f. f?chf. Dberforftmeifter. f. f?chf. Dberforftrath. herz. braunfchweig. Forftmeifter von Blanfenburg. Direftor der fürftlich Cfterhazh’fchen Herrfchaft Spoly Parsto. fürftl. fondershauf. Dberfortmeifter. f. bahr. Redierf?rfter don Schmarzenbach. f. preuk. Dberf?rfter. f. f. Forftrath aus Brekburg. f. preuk. Dberf?rfter von Altruppin. f. hann?v. Forftmeifter von Rienburg. Forftmeifter in preuk. Schleften. f. preuk. Dberforftmeifter von Berlin. herz. aftenburg. Dberfortmeifter. f. preuk. Dberf?rfter. f. f?chf. Dberf?rfter. f. ruff. Forftfomiff?r aus Marfchau. f. preuk. Forftinfpeftor. f. f?chf. Forftinfpeftor. grokh. meimar. Forftinfpeftor von Martfuhl. f. mürttb. Dberf?rfter und Brofeffor aus Hohenheim. f. hannov. Forftmeifter aus Hammeln. Dberforftmeifter aus Sotha. herz. altenburg. Dberf?rfter aus Hummelshain. herz. altenburg. Revierf?rfter aus Milchwig. herz. altenburg. geheimer Finanzrath und Dberforftmeifter. herz. altenb. Dberforftmeifter aus Hummelshain. grokh. f?chf. geheimer Dberforftrath aus Qifenach. herz. naffau. Dberforftrath aus Miesbaden. grokh. heff. Dberforftfefret?r aus Darmftadt. f. f?chf. Dberforftmeifter.     

Forest management and carbon sequestration in wood products

Wood products are considered to contribute to the mitigation of carbon dioxide emissions. A critical gap in the life cycle of wood products is to transfer the raw timber from the forest to the processing wood industry and, thus, the primary wood products. Therefore, often rough estimates are used for this step to obtain total forestry carbon balances. The objectives of this study were (1) to examine the fate of timber harvested in Thuringian state forests (central Germany), representing a large, intensively managed forested region, and (2) to quantify carbon stocks and the lifetime of primary wood products made from this timber. The analyses were based on the amount and assortments of actually sold timber, and production parameters of the companies that bought and processed this timber. In addition, for coniferous stands of a selected Thuringian forest district, we calculated potential effects of management, as expressed by different thinning regimes on wood products and their lifetimes. Total annual timber sale of soft- and hardwoods from Thuringian state forests (195,000 ha) increased from about 136,893 t C (~0.7 t C ha⁻¹ year⁻¹) in 1996 to 280,194 t C (~1.4 t C ha⁻¹ year⁻¹) in 2005. About 47% of annual total timber harvest went into short-lived wood products with a mean residence time (MRT) < 25 years. Thirty-one per cent of the total harvest went into wood products with an MRT of 25–43 years, and only 22% was used as construction wood and glued wood, products with the longest MRT (50 years). The average MRT of carbon in harvested wood products was 20 years. Thinning from above throughout the rotation of spruce forests would lead to an average MRT in harvested wood products of about 23 years, thinning from below of about 18 years. A comparison of our calculations with estimates that resulted from the products module of the CO2FIX model (Nabuurs et al. 2001) demonstrates the influence of regional differences in forest management and wood processing industry on the lifetime of harvested wood products. To our knowledge, the present study provides for the first time real carbon inputs of a defined forest management unit to the wood product sector by linking data on raw timber production, timber sales and wood processing. With this new approach and using this data, it should be possible to substantially improve the net-carbon balance of the entire forestry sector.     

Midwest (U.S.A.) reservoir water quality modification

The impact of a flood control, low flow argumentation reservoir in the Midwestern part of the United States on BOD, COD, and ammonia was evaluated in this paper. Fifteen years of weekly water quality data (9 yr before impoundment and 6 yr after impoundment) from four sampling stations upstream and downstream of the reservoir were available for analysis. The annual loading rates of these parameters (kg ha^?1 vr^?1) were found to correlate well with annual runoff (cm yr^?1). Besides, the reservoir was found to have had a significant and beneficial impact on the downstream loading rates of BOD and COD, which were reduced by 55 and 75%, respectively. As for ammonia, the results of this study indicate that its annual loadings at downstream locations were not significantly affected by the reservoir. Average non-point source contributions of BOD and ammonia loadings into the system were found to be about 80 and 55%, respectively.