De inpassing van de Barbierbeek in het gecontroleerd overstromingsgebied Kruibeke-Bazel-Rupelmonde

This report deals with the possibilities to fit the Barbier-brook in the Controlled lnundation Area of Kruibeke, Bazel en Rupelmonde that was planned according the Sigmaplan. The so called CIA-KBR is situated upstream Antwerp. The CIA-KBR will be inundated when a certain flood on the river Schelde overflows the lowered river dike. The result is a decrease of the peak of the flood. A dike at the polder side will fulfill the defensive function during the period of inundation. This dike is called the "ringdike". The Barbier-brook cuts through the CIA-KBR. Within the CIA the Barbier-brook is diked in since the 13th century. Further on in this text these dikes will be called Barbier-brook dikes. Nowadays, the area between these dikes forms the storage for the Barbier-brook.The study participates in the preparations for the CIA-KBR. Co-ordinated by the Institute of Nature Conservation in Brussels some studies for possibilities of nature development within the CIA-KBR are carried out.In this report the technical possibilities to fit the Barbier-brook in the CIA-KBR as weIl as the perspectives for nature developrnent are studied. The perspectives for nature development can be split in:.nature development influenced by the Barbier-brook.nature development influenced by the Barbier-brook and a controlled reduced tide, controlled reduced tide stands for: a tide controlled by culverts for the in- and outlet of water from the river Schelde with a reduced tide amplitude with an average of 0,25 to 0,5 m.This last perspective corresponds most to the historical natural situation of the area, which consists of freshwater marshes and mud plains.To be able to work out these aspects it is necessary to carry out also a study ofthe water quality and quantity of the Barbier-brook.No discharge data from the Barbier-brook are known at all. Based on the discharge data of the Kleine Molenbeek near Liezele, which has a similar catchment area except the size, the discharge frorn the Barbier-brook could be abstracted. To do so, the surface area of the Kleine Molenbeek is multiplied by a factor 1,43. Frorn these discharge data follows a mean discharge of the Barbier-brook which varies seasonally between 3 and 5 m3/s. These data show also an increase in the annual maximum 24h-discharges starting from approximately 1980.The quality of the water of the Barbier-brook off the CIA-KBR is very bad. The brook is heavily polluted with domestic, industrial and agricultural wastewater. Nearby the site where the brook discharges into the Schelde it is characterised as "biologically dead". The involved communities have made sewerage plans which will decrease the pollution of the Barbier-brook with dornestic wastewater with about 80%. Concerning the houses which are not covered by the sewerage plans the following measures are given: 1) yet inc1ude into the sewerage plans, and 2) provide small-scale biological treatment.After completion of the sewerage plans and the extra measures the following reductions of the pollution by wastewater on the Barbier-brook could be reached:dornestic wastewater: 92%; industrial wastewater: 90%; agricultural wastewater: 31 %To make it technically possible to fit the Barbier-brook in the CIA-KBR it is necessary to compensate the storage of the Barbier-brook in order to prevent the brook to cause trouble at the houses of Bazel that stand close to the brookside. For this reason the following measures will be elaborated:The realisation of a storage along the ringdike which is connected with the CIA by means of a culvert. The surface needed for the storage is regulated by the maximum water level that is tolerated in the storage. From calculations follows that there is enough place to realise a storage that can guarantee a safety for a situation with a return period of 1 per 1000 years. No houses need to be removed.The realisation of a storage in the natural valley of the Barbier-brook situated upstream Bazel and the CIA. This storage needs to be fit in the protected landscape without large works. From calculations follows that the available storage volume is insufficient to guarantee a safety for a situation with a return period of 1 per 1000 years.Placing a pumping station at the ringdike with sufficient capacity to pump over a discharge of the Barbier-brook with a return period of 1 per 400 years which is 8,7 m3/s. It is technically possible to reach this with a "screw-up-pumping station" as well as with a "screw-centrifugal-pumping station”Not until the quality of the water of the Barbier-brook improves strongly, nature development can be effectively worked out. In this study the following perspectives for nature development are elaborated in order to increase the value of nature in that part of the CIA that can be influenced by the Barbier-brook:.Concerning the area between the Barbier-brook dikes possible measures are worked out to improve the present potential values of nature. Thus rich zones along the Creek of Kruibeke can be expected and the higher grounds will be rich in flowering plants. When the dikes around the Barbier-brook are preserved the introduction of a controlled reduced tide is of no influence concerning nature development of the Barbier-brook..Concerning a part of the polder of Kruibeke space will be created for development of a more natural Barbier-brook. The agricultural activities on the other grounds will be preserved. Different measures will make this possible of which one is the removal of the Northern Barbier-brook dike. There will be aimed towards broad and rich developed zones along the brook with gradation in vegetation types. The introduction of a controlled reduced tide is not considered because of the present function of agriculture in the polder ..Concerning the polders of Kruibeke and Bazel measures are worked out to provide a total free development of the Barbier-brook. The most effective measure to reach this is the removal of the Barbier-brook dikes except that part of the dikes between the new ringdike and the natural height in the polder of Bazel. There will be a striving towards a large scaled landscape dominated by reeds and rich developed wetlands. The introduction of a controlled reduced tide is of great influence of the nature development in this situation. It might even re sult in freshwater marshes and mud plains in the CIA-KBR

Hydrothermal activity, functional diversity and chemoautotrophy are major drivers of seafloor carbon cycling

Hydrothermal vents are highly dynamic ecosystems and are unusually energy rich in the deep-sea. In situ hydrothermal-based productivity combined with sinking photosynthetic organic matter in a soft-sediment setting creates geochemically diverse environments, which remain poorly studied. Here, we use comprehensive set of new and existing field observations to develop a quantitative ecosystem model of a deep-sea chemosynthetic ecosystem from the most southerly hydrothermal vent system known. We find evidence of chemosynthetic production supplementing the metazoan food web both at vent sites and elsewhere in the Bransfield Strait. Endosymbiont-bearing fauna were very important in supporting the transfer of chemosynthetic carbon into the food web, particularly to higher trophic levels. Chemosynthetic production occurred at all sites to varying degrees but was generally only a small component of the total organic matter inputs to the food web, even in the most hydrothermally active areas, owing in part to a low and patchy density of vent-endemic fauna. Differences between relative abundance of faunal functional groups, resulting from environmental variability, were clear drivers of differences in biogeochemical cycling and resulted in substantially different carbon processing patterns between habitats

Reef communities associated with ‘dead’ cold-water coral framework drive resource retention and recycling in the deep sea

Cold-water coral (CWC) reefs create hotspots of metabolic activity in the deep sea, in spite of the limited supply of fresh organic matter from the ocean surface (i.e. phytodetritus). We propose that ‘dead’ coral framework, which harbours diverse faunal and microbial communities, boosts the metabolic activity of the reefs, through enhanced resource retention and recycling. Analysis of a video transect across a 700-540 m-deep CWC mound (Rockall Bank, North-East Atlantic) revealed a high benthic cover of dead framework (64%). Box-cored fragments of dead framework were incubated on-board and showed oxygen consumption rates of 0.078–0.182 μmol O2 (mmol organic carbon, i.e. OC)-1 h-1, indicating a substantial contribution to the total metabolic activity of the CWC reef. During the incubations, it was shown that the framework degradation stage influences nitrogen (re)cycling, corresponding to differences in community composition. New (less-degraded) framework released ammonium (0.005 ± 0.001 μmol NH4+ (mmol OC) 1 h 1), probably due to the activity of ammonotelic macrofauna. In contrast, old (more-degraded) framework released nitrate (0.015 ± 0.008 μmol NO3- (mmol OC)- 1 h- 1), indicating that nitrifying microorganisms recycled fauna-excreted ammonium to nitrate. Furthermore, the framework community removed natural dissolved organic matter (DOM) from the incubation water (0.005–0.122 μmol C (mmol OC)- 1 h- 1). Additional feeding experiments showed that all functional groups and macrofauna taxa of the framework community incorporated 13C-enriched (‘labelled’) DOM, indicating widespread DOM uptake and recycling. Finally, the framework effectively retained 13C-enriched phytodetritus, (a) by physical retention on the biofilm-covered surface and (b) by biological filtration through suspension-feeding fauna. We therefore suggest that the dead framework acts as a ‘filtration-recycling factory’ that enhances the metabolic activity of CWC reefs. The exposed framework, however, is particularly vulnerable to ocean acidification, jeopardizing this important aspect of CWC reef functioning

Tight cooperation between Mot1p and NC2β in regulating genome-wide transcription, repression of transcription following heat shock induction and genetic interaction with SAGA

TATA-binding protein (TBP) is central to the regulation of eukaryotic transcription initiation. Recruitment of TBP to target genes can be positively regulated by one of two basal transcription factor complexes: SAGA or TFIID. Negative regulation of TBP promoter association can be performed by Mot1p or the NC2 complex. Recent evidence suggests that Mot1p, NC2 and TBP form a DNA-dependent protein complex. Here, we compare the functions of Mot1p and NC2βduring basal and activated transcription using the anchor-away technique for conditional nuclear depletion. Genome-wide expression analysis indicates that both proteins regulate a highly similar set of genes. Upregulated genes were enriched for SAGA occupancy, while downregulated genes preferred TFIID binding. Mot1p and NC2β depletion during heat shock resulted in failure to downregulate gene expression after initial activation, which was accompanied by increased TBP and RNA pol II promoter occupancies. Depletion of Mot1p or NC2β displayed preferential synthetic lethality with the TBP-interaction module of SAGA. Our results support the model that Mot1p and NC2β directly cooperate in vivo to regulate TBP function, and that they are involved in maintaining basal expression levels as well as in resetting gene expression after induction by stress

Hydrology and Earth System Sciences The International Soil Moisture Network: a data hosting facility for global in situ soil moisture measurements

Abstract. In situ measurements of soil moisture are invaluable for calibrating and validating land surface models and satellite-based soil moisture retrievals. In addition, longterm time series of in situ soil moisture measurements themselves can reveal trends in the water cycle related to climate or land cover change. Nevertheless, on a worldwide basis the number of meteorological networks and stations measuring soil moisture, in particular on a continuous basis, is still limited and the data they provide lack standardization of technique and protocol

Bacterial Leaf Symbiosis in Angiosperms: Host Specificity without Co-Speciation

Bacterial leaf symbiosis is a unique and intimate interaction between bacteria and flowering plants, in which endosymbionts are organized in specialized leaf structures. Previously, bacterial leaf symbiosis has been described as a cyclic and obligate interaction in which the endosymbionts are vertically transmitted between plant generations and lack autonomous growth. Theoretically this allows for co-speciation between leaf nodulated plants and their endosymbionts. We sequenced the nodulated Burkholderia endosymbionts of 54 plant species from known leaf nodulated angiosperm genera, i.e. Ardisia, Pavetta, Psychotria and Sericanthe. Phylogenetic reconstruction of bacterial leaf symbionts and closely related free-living bacteria indicates the occurrence of multiple horizontal transfers of bacteria from the environment to leaf nodulated plant species. This rejects the hypothesis of a long co-speciation process between the bacterial endosymbionts and their host plants. Our results indicate a recent evolutionary process towards a stable and host specific interaction confirming the proposed maternal transmission mode of the endosymbionts through the seeds. Divergence estimates provide evidence for a relatively recent origin of bacterial leaf symbiosis, dating back to the Miocene (5–23 Mya). This geological epoch was characterized by cool and arid conditions, which may have triggered the origin of bacterial leaf symbiosis

Allocation to highly sensitized patients based on acceptable mismatches results in low rejection rates comparable to non-sensitized patients

Whereas regular allocation avoids unacceptable mismatches on the donor organ, allocation to highly sensitized patients within the Eurotransplant Acceptable Mismatch (AM) program is based on the patient's HLA phenotype plus acceptable antigens. These are HLA antigens to which the patient never made antibodies, determined by extensive laboratory testing. AM patients have superior long-term graft survival compared to highly sensitized patients in regular allocation. Here, we questioned whether the AM program also results in lower rejection rates. From the PROCARE cohort, consisting of all Dutch kidney transplants 1995-2005, we selected deceased donor single transplants with minimum one HLA mismatch and determined the cumulative 6-month rejection incidence for patients in AM or regular allocation. Additionally, we determined the effect of minimal matching criteria of one HLA-B plus one HLA-DR, or two HLA-DR antigens on rejection incidence. AM patients showed significantly lower rejection rates than highly immunized patients in regular allocation, comparable to non-sensitized patients, independent of other risk factors for rejection. Contrasting to highly sensitized patients in regular allocation, minimal matching criteria did not affect rejection rates in AM patients. Allocation based on acceptable antigens leads to relatively low risk transplants for highly sensitized patients with rejection rates similar to non-immunized individuals. This article is protected by copyright. All rights reserved.</p

The opposing transcriptional functions of Sin3a and c-Myc are required to maintain tissue homeostasis.

How the proto-oncogene c-Myc balances the processes of stem-cell self-renewal, proliferation and differentiation in adult tissues is largely unknown. We explored c-Myc's transcriptional roles at the epidermal differentiation complex, a locus essential for skin maturation. Binding of c-Myc can simultaneously recruit (Klf4, Ovol-1) and displace (Cebpa, Mxi1 and Sin3a) specific sets of differentiation-specific transcriptional regulators to epidermal differentiation complex genes. We found that Sin3a causes deacetylation of c-Myc protein to directly repress c-Myc activity. In the absence of Sin3a, genomic recruitment of c-Myc to the epidermal differentiation complex is enhanced, and re-activation of c-Myc-target genes drives aberrant epidermal proliferation and differentiation. Simultaneous deletion of c-Myc and Sin3a reverts the skin phenotype to normal. Our results identify how the balance of two transcriptional key regulators can maintain tissue homeostasis through a negative feedback loop

Foraminiferal assemblages as palaeoenvironmental bioindicators in Late Jurassic epicontinental platforms: relation with trophic conditions

Foraminiferal assemblages from the neritic environment reveal the palaeoecological impact of nutrient types in relation to shore distance and sedimentary setting. Comparatively proximal siliciclastic settings from the Boreal Domain (Brora section, Eastern Scotland) were dominated by inner−shelf primary production in the water column or in sea bottom, while in relatively seawards mixed carbonate−siliciclastic settings from the Western Tethys (Prebetic, Southern Spain), nutrients mainly derived from the inner−shelf source. In both settings, benthic foraminiferal assemblages increased in diversity and proportion of epifauna from eutrophic to oligotrophic conditions. The proximal setting example (Brora Brick Clay Mb.) corresponds to Callovian offshore shelf deposits with a high primary productivity, bottom accumulation of organic matter, and a reduced sedimentation rate for siliciclastics. Eutrophic conditions favoured some infaunal foraminifera. Lately, inner shelf to shoreface transition areas (Fascally Siltstone Mb.), show higher sedimentation rates and turbidity, reducing euphotic−zone range depths and primary production, and then deposits with a lower organic matter content (high−mesotrophic conditions). This determined less agglutinated infaunal foraminifera content and increasing calcitic and aragonitic epifauna, and calcitic opportunists (i.e., Lenticulina). The comparatively distal setting of the Oxfordian example (Prebetic) corresponds to: (i) outer−shelf areas with lower nutrient input (relative oligotrophy) and organic matter accumulation on comparatively firmer substrates (lumpy lithofacies group) showing dominance of calcitic epifaunal foraminifera, and (ii) mid−shelf areas with a higher sedimentation rate and nutrient influx (low−mesotrophic conditions) favouring potentially deep infaunal foraminifers in comparatively unconsolidated and nutrient−rich substrates controlled by instable redox boundary (marl−limestone rhythmite lithofacies).This research was carried out with the financial support of projects CGL2005−06636−C0201 and CGL2005−01316/BTE, and University of Oslo, Norway−Statoil cooperation. M.R. holds a Juan de la Cierva grant from the Ministry of Science and Technology of Spain