Use of the gef gene in a biological containment system in soil microcosms

Summary Data on the use of a biological containment system in microcosms are presented. The system is based on a transposon Tn5-cassette containing a fusion of the lac promoter and gef controlled by lacI^Q. The suicide function was inserted into different bacterial hosts and its induction by isopropyl--d-thiogalactoside (IPTG) was tested in sterile and non-sterile soil microcosms. The results suggest that the killing effect of this gef-based suicide mechanism is insufficient under soil conditions.     

Reaction of 25 Apomictic Apple Rootstock Selections to Inoculation with Mixtures of ’latent’ Viruses

Malus sieboldii, M. sargenti and most hybrids showed sensitivity to inoculation with mixtures of ‘latent’ viruses from apple cultivars. The main symptoms were chlorotic leaf spots and leaf distortions combined with severe stunting in many seedlings. There was no reaction in the M. hupehensis group and Bittenfelder Seedling except for stem pitting or stem grooving symptoms in two hybrids. It is suggested that the same sensitivity reaction to apple ’latent’ viruses which leads to incompatibility when apple rootstocks are budded may also cause virus symptoms in apomictic species rootstocks. This would seem to apply especially to the M. sieboldii and M. sargenti groups, but probably not to the M. hupehensis group.     

Soil organic C as affected by silvicultural and exploitative interventions in Nothofagus pumilio forests of the Chilean Patagonia

This study evaluates the effect of silvicultural and exploitative interventions on soil organic carbon (SOC) in Chilean Lenga (Nothofagus pumilio (Poepp et Endl.) Krasser) forests in south Patagonia. We analyzed SOC and the organic soil horizons in five stands at different stages of development: intact native forest (NI); a 3-year-old shelterwood stand (S3); an 8-year-old shelterwood stand (S8); a 14-year-old stand that was initially treated with shelterwood and subsequently final cut (10 years after the first intervention) (S14), and a 25-year-old stand subject to a exploitative intervention (E25). The SOC under the forest stands, down to a depth of 50 cm (including the Oi horizon), was 60, 55, 71, 85, and 67 Mg ha⁻¹ for the NI, S3, S8, S14, and E25 forest stands, respectively. A significant decrease in SOC occurred 3 years after an intensive shelterwood cut (S3), particularly in the first 5 cm of the mineral soil. Slightly higher carbon contents were observed in the upper horizons of the mineral soil in both the S8 and S14 stands. Consequently, the applied shelterwood system appears to generate only short-term losses of SOC in the Lenga forest. Soil organic carbon increased over the medium term but decreased to the level observed in intact native forests over the long term. Regeneration, which influences stand microclimate (a factor in SOC storage) and provides an important source of organic soil material, was identified as one of the most important factors influencing SOC.     

Correlations between the behavior of recreational horses,the physiological parameters and summer atmospheric conditions

The aim of this paper was to select atmospheric factors and their values, which may disrupt the correct behavior and physiological condition of recreational horses. The studies were carried out from 1 July until 1 September on 16 Anglo‐Arabian geldings. Each day, from 09.00 to 10.00 hours, the horses worked under saddle. The riders and the authors gave a qualitative behavioral assessment for each horse. Mood and willingness to work were evaluated. The quantitative assessment was called ‘incorrect behavior of the horse while riding’ (IBHR). The percentage time of duration and the number of occurrences of the features while riding were calculated. Heart rate, body temperature and respiratory rate were taken at 08.00 hours (resting measurement) and at 10.05 hours (post‐exercise measurement). Air temperature, relative air humidity, wind speed and atmospheric pressure were measured at 08.00 and 10.00 hours. The results showed that adverse changes in the behavior of recreational horses can occur if the horse is ridden when the air temperature is above 26°C and when wind speeds exceed 5.5 m/s. Such conditions may cause a reduction in the mood and willingness to work in horses. Physiological parameters like heart rate and body temperature seem to be more sensitive indicators of the horse body reaction to the weather than behavioral reactions.     

The feeding ecology of earthworms – A review

Current knowledge of earthworm feeding ecology is reviewed, with particular reference to food selection, ingestion, digestion and assimilation, and the use of novel techniques to advance understanding of the functional significance of these processes.

Traditional research methods including direct observation of feeding behaviour, gut content analysis, choice tests, and litter bags have provided a wealth of information on earthworm feeding. However, there is a lack of the mechanistic, quantitative information required to characterise adequately their functional role in soil ecosystem processes such as soil C sequestration and loss, decomposition of organic residues, the maintenance of soil structure and trophic interactions with plants and microorganisms.

Stable isotope ratio analysis of light elements (C, N, and S) offers a powerful research tool to reveal and quantify trophic relationships of earthworms in soil food webs, while molecular techniques can further enhance understanding of the interactions between earthworms and microorganisms and their functional significance.     

Breeding and characterization of soybean Triple Null; a stack of recessive alleles of Kunitz Trypsin Inhibitor,Soybean Agglutinin,and P34 allergen nulls

Soybean (Glycine max) seeds contain bioactive proteins with antinutritional and immunological properties that affect metabolism and assimilation of nutrients. The presence of antinutritional proteins requires soybeans to be heat‐treated resulting in input energy costs. Nulls for bioactive seed proteins have been previously isolated from the USDA soybean collection, including Kunitz trypsin inhibitor (TI), soybean agglutinin (LE) and immunodominant soybean allergen P34 protein. Each of these nulls has the potential to partially address the concerns of soybean feed/food consumption. A stack of recessive nulls of TI, LE and P34 was created in a cv ‘Williams 82’ background termed ‘Triple Null’. Triple Null has a slight reduction of total protein compared with ‘Williams 82’ corresponding to aggregate contribution of TI, LE and P34 in the seed proteome. Triple Null's proteome analysis revealed P34 and TI nulls are frame‐shift mutants able to accumulate small amounts of authentic P34 and TI proteins. Triple Null has possible application as a conventional feed/food source and for immunotherapy to mitigate soybean allergenic response.     

Can the thermodynamic melting temperature of sucrose, glucose, and fructose be measured using rapid-scanning differential scanning calorimetry (DSC)?

The loss of crystalline structure in sucrose, glucose, and fructose has been shown to be due to the kinetic process of thermal decomposition (termed apparent melting), rather than thermodynamic melting. The purpose of this research was to investigate whether or not it is possible to scan quickly enough to suppress the kinetic process of thermal decomposition and reach the thermodynamic melting temperature of these sugars using a new rapid-scanning DSC. Indium, a thermodynamic melting material, and sucrose, glucose, and fructose were analyzed at three heating rates from 1 to 25 °C/min using standard DSC and at seven heating rates from 50 to 2000 °C/min using rapid-scanning DSC. Thermodynamic melting was achieved when the onset temperature (T(m onset)) of the endothermic peak leveled off to a constant value independent of heating rate. The T(m onset) for indium was constant (156.74 ± 0.42 °C) at all heating rates. In the case of fructose, the T(m onset) increased considerably until a heating rate of approximately 698 °C/min, after which the average T(m onset) for the remaining three heating rates was constant at 135.83 ± 1.14 °C. Thus, 135.83 °C is proposed to be the thermodynamic melting temperature of fructose. It is important to note that the heating rate at which this thermodynamic melting temperature is achieved is most likely influenced by the type and amount of trace components (e.g., water and salts) contained in the fructose, which are known to vary widely in sugars. In the case of sucrose and glucose, thermodynamic melting temperatures were not able to be obtained, because the upper limit heating rate used was not fast enough to suppress thermal decomposition and achieve thermodynamic melting, perhaps due to the higher apparent T(m onset) for sucrose and glucose compared to that for fructose.     

Soil monitoring in Germany

Background Aim and Scope

Soil monitoring in Germany should register the current soil condition, monitor its changes and provide a forecast for future development. In order to achieve these goals, the long-term soil monitoring sites in Germany (BDF -Bodendauerbeobachtungsflächen) have been established by the federal states. This has been done according to criteria worked out by soil monitoring experts. In this article a method for the examination of the suitability of Germany’s soil monitoring sites for soil conservation and protection purposes, as well as for environmental monitoring and reporting, is introduced. This method includes the landscape representativity of soil monitoring sites as well as the comparability and spatial validity of collected data.

Methods

BDF-criteria are operationalized in a three-step procedure: At first, a metadatabase is established containing information that allows the comparison of monitoring sites by means of measuring parameters, methods and quality assurance as well as quality control of measurements. Secondly, the representativity of the BDF-sites for soil types, land use, vegetation, and climate (air temperature, duration of sunlight, precipitation) by means of frequency statistics and neighborhood analysis is quantified. At last, the spatial validity of soil monitoring data is examined through the application of geostatistical methods. Both data and statistical methods are integrated in a Geoinformationsystem (GIS).

Results

The analysis of metadata reveals that the soil monitoring is of great importance for environmental analysis because of its ecosystematic concept and its considerable degree of methodical harmonization. Assuming that the number of BDF should be directly proportional to the areal portion of an ecoregion in the entire area of Germany, it can be shown that the geographical distribution of BDF-sites fit quite well according to the areal portions of the ecoregions. The maximum deviation is about ñ 6%. If the number of BDF is not proportional to the area covered by a certain combination of site characteristics, these areas can either be complemented or thinned through MNR-indices derived by neighborhood analysis. Soil monitoring sites can be added where the MNR are highest and removed where MNR are lowest. Throughout the neighborhood analysis, three GISmaps were processed: ecoregionaiization, soil types and land use. Decisions to reduce the spatial density of monitoring sites should not only be based on the landscape representativness of monitoring networks, but on the support of geostatistical analysis of measured data as well. For example, the results of the geostatistical analysis of Pb-concentrations in top soils are compared for a complete and a reduced BDF monitoring network.

Conclusion

The investigations show that not only the proportional distribution of monitoring sites in landscape units (landscape representativity) is important for the assessment of environmental monitoring networks; The number of monitoring sites, rather, should be sufficient to guarantee a spatial representation of the respective measurement variable. Their geographical distribution should be based on the spatial model of landscape units. Additionally, particular criteria that are important for the object of investigation, for example the distance to emitters, should also be considered.

Perspective

It is strongly recommended that activities for the integration of ecological data collected in diverse monitoring networks be intensified. A central German environmental information system should be established in order to realize integrated analysis of environmental data by aspects of harmonization and representativity. Furthermore, Internet and GIS technologies should be used to assist the environmental data acquisition in Germany. A prototype of such an instrument, the socalled Internet and GIS-based Environmental Monitoring System (IGUS) was already established and tested in the moss monitoring program 2000.