bluuebunny/crossref_metadata_2025 huggingface dataset:
In Silico screening for agonists and blockers of the β2 adrenergic receptor: Implications of inactive and activated state structures
Authors: Costanzi Stefano , Vilar Santiago
Published: December 2011

Ten crystal structures of the β2 adrenergic receptor have been published, reflecting different signaling states. Here, through controlled‐docking experiments, we examined the implications of using inactive or activated structures on the in silico screening for agonists and blockers of the receptor. Specifically, we targeted the crystal structures solved in complex with carazolol (2RH1), the neutral antagonist alprenalol, the irreversible agonist FAUC50 (3PDS), and the full agonist BI‐167017 (3P0G). Our results indicate that activated structures favor agonists over blockers, whereas inactive structures favor blockers over agonists. This tendency is more marked for activated than for inactive structures. Additionally, agonists tend to receive more favorable docking scores when docked at activated rather than inactive structures, while blockers do the opposite. Hence, the difference between the docking scores attained with an activated and an inactive structure is an excellent means for the classification of ligands into agonists and blockers as we determined through receiver operating characteristic curves and linear discriminant analysis. With respect to virtual screening, all structures prioritized well agonists and blockers over nonbinders. However, inactive structures worked better for blockers and activated structures worked better for agonists, respectively. Notably, the combination of individual docking experiments through receptor ensemble docking resulted in an excellent performance in the retrieval of both agonists and blockers. Finally, we demonstrated that the induced‐fit docking of agonists is a viable way of modifying an inactive crystal structure and bias it toward the in silico recognition of agonists rather than blockers. © 2011 Wiley Periodicals, Inc. J Comput Chem, 2011
Bone morphogenetic protein receptor type Ia localization causes increased BMP2 signaling in mice exhibiting increased peak bone mass phenotype
Authors: Bragdon Beth , Bonor Jeremy , Shultz Kathryn L. , Beamer Wesley G. , Rosen Clifford J. , Nohe Anja
Published: December 2011

Bone morphogenetic protein 2 (BMP2) is a growth factor that initiates osteoblast differentiation. Recent studies show that BMP2 signaling regulates bone mineral density (BMD). BMP2 interacts with BMP receptor type Ia (BMPRIa) and type II receptor leading to the activation of the Smad signaling pathway. BMPRIa must shuttle between distinct plasma membrane domains, enriched of Caveolin‐1 alpha and Caveolin‐1 beta isoforms, and receptor activation occurs in these domains. Yet it remains unknown whether the molecular mechanism that regulates BMP2 signaling is driving mineralization and BMD. Therefore, the B6.C3H‐1‐12 congenic mouse model with increased BMD and osteoblast mineralization was utilized in this study. Using the family image correlation spectroscopy, we determined if BMP2 led to a significant re‐localization of BMPRIa to caveolae of the alpha/beta isoforms in bone marrow stromal cells (BMSCs) isolated from B6.C3H‐1‐12 mice compared to the C57BL/6J mice, which served as controls. The control, C57BL/6J mice, was selected due to only 4 Mb of chromosome 1 from the C3H/HeJ mouse was backcrossed to a C57BL/6J background. Using reporter gene assays, the B6.C3H‐1‐12 BMSCs responded to BMP2 with increased Smad activation. Furthermore, disrupting caveolae reduced the BMP2‐induced Smad signaling in BMSCs isolated from B6.C3H‐1‐12 and C57BL/6J. This study suggests for the first time a regulatory mechanism of BMPRIa signaling at the plasma membrane of BMSCs that (i) associated with genetic differences in the distal Chromosome 1 segment carried by the B6.C3H‐1‐12 congenic and (ii) contributes to increase BMD of the B6.C3H‐1‐12 compared to the C57BL/6J control mice. J. Cell. Physiol. 227: 2870–2879, 2012. © 2011 Wiley Periodicals, Inc.
Development and evaluation of a trehalose‐contained solution formula to preserve hUC‐MSCs at 4°C
Authors: Di Guohu , Wang Jiexi , Liu Minxia , Wu Chu‐Tse , Han Ying , Duan Haifeng
Published: December 2011

Human mesenchymal stem cells (hMSCs) hold great promise in cell therapy and regenerative medicine. Various preclinical and clinical trials have been carried out to illustrate the therapeutic potential of these cells. However, one major challenge for manufacturing clinical grade hMSCs is the requisition of current good manufacturing practice (cGMP) grade practices in cell isolation, processing, storage, and distribution. Development of non‐toxic and animal serum‐free preservation medium is critical for storage and distribution of mesenchymal stem cells (MSCs). In this study, we developed a solution formula that could preserve MSCs at 4°C for up to 3 weeks. In the solution, trehalose is a key ingredient for maintaining survival of MSCs. Among the concentrations investigated, 40 mM trehalose showed the best outcome with the viability maintained more than 92.7 ± 1.5% for 7 days. Cells preserved in the solution formula for 3 weeks still remained about 70% viability, and produced results similar to those of freshly harvested hMSCs in terms of growth kinetics, expression profile of cell surface antigens, and differentiation potential. In summary, storage of MSCs in the medium makes it far easier for transporting the cells from processing units to clinical sites. J. Cell. Physiol. 227: 879–884, 2012. © 2011 Wiley Periodicals, Inc.
The role of COX‐2/PGE2 in gossypol‐induced apoptosis of colorectal carcinoma cells
Authors: Chien Chih‐Chiang , Ko Ching‐Huai , Shen Shing‐Chuan , Yang Liang‐Yo , Chen Yen‐Chou
Published: December 2011

Our previous study showed that gossypol (GOS) exhibits potent cytotoxic effects via apoptosis induction against human colorectal carcinoma cells; however, the role of cyclooxygenase (COX)‐2/prostaglandin (PG)E2 on GOS‐induced apoptosis is still unknown. In the present study, 12‐O‐tetradecanoylphorbol‐13‐acetate (TPA) addition significantly inhibited GOS‐induced apoptosis in human colorectal carcinoma HT‐29 cells in accordance with inducing COX‐2 protein/PGE2 production. TPA inhibition of GOS‐induced apoptosis was blocked by adding protein kinase (PK)C inhibitors including staurosporine (ST), GF109203X (GF), and H7, characterized by the occurrence of cleaved caspase 3 proteins and a decrease in COX‐2 protein/PGE2 production in HT‐29 cells. The addition of COX activity inhibitors, including NS398 (NS), aspirin (AS), diclofenac (DI), and indomethacin (IN), suppressed TPA protection of GOS‐induced apoptosis with decreased PGE2 production in HT‐29 cells. Application of PGE2, but not it analogs PGD2, PGJ2, or PGF2α, protected HT‐29 cells from GOS‐induced DNA ladders, and the E‐prostanoid (EP1) receptor agonist, 17PT‐PGE2, mimicked the protection induced by PGE2, whereas the selective EP2 receptor agonist, butaprostol (BUT), the EP3 receptor agonist, sulprostol (SUL), and the EP4 receptor agonist, PGE1 alcohol (PGE1), showed no significant effects on GOS‐induced apoptosis in HT‐29 cells. PGE2's protection against GOS‐induced apoptosis was reversed by adding the selective EP1 receptor antagonist, SC‐19220. Furthermore, GOS had an effective apoptotic effect on COLO205 colorectal carcinoma cells which expressed undetectable level of endogenous COX‐2 protein than HT‐29 cells, and the decreased COX‐2 protein level via COX‐2 siRNA or addition of COX‐2 activity inhibitor NS significantly elevated GOS‐induced cell death in HT‐29 cells. COLO205‐T cells were established through sustained TPA incubation of COLO205 cells, and COLO205‐T cells showed a lower sensitivity to GOS‐induced cell death with increased COX‐2 (not Bcl‐2 and Mcl‐1) protein than parental COLO‐205 cells. A decrease in COX‐2 protein expression in COLO205‐T cells by COX‐2 siRNA transfection or enhanced GOS‐induced cell death according to MTT assay and DNA integrity assay. The notion of COX‐2/PGE2 activation against GOS‐induced apoptosis in colon carcinoma cells was demonstrated, and the combination of GOS and COX‐2 inhibitors to treat colon carcinoma possesses clinical potential worthy of further investigation. J. Cell. Physiol. 227: 3128–3137, 2012. © 2011 Wiley Periodicals, Inc.
Matrine modulates HSC70 levels and rescues ΔF508‐CFTR
Authors: Basile Anna , Pascale Maria , Franceschelli Silvia , Nieddu Erika , Mazzei Marco T. , Fossa Paola , Turco Maria Caterina , Mazzei Mauro
Published: December 2011

Cystic fibrosis transmembrane conductance regulator (CFTR) is a cAMP‐dependent Cl− channel located in the plasma membrane, and its malfunction results in cystic fibrosis (CF), the most common lethal genetic disease in Caucasians. Most CF patients carry the deletion of Phe508 (ΔF508 mutation); this mutation prevents the delivery of the CFTR to its correct cellular location, the apical (lumen‐facing) membrane of epithelial cells. Molecular chaperones play a central role in determining the fate of ΔF508‐CFTR. In this report, we show that the Matrine, a quinolizidine alkaloid, downregulates the expression of the molecular chaperone HSC70 and increases the protein levels of ΔF508‐CFTR in human alveolar basal epithelial cells (A549 cell line), stably transfected with a ΔF508‐CFTR‐expressing construct. Moreover, Matrine induced ΔF508‐CFTR release from endoplasmic reticulum to cell cytosol and its localization on the cell membrane. Interestingly, downregulation of HSC70 resulted in increased levels of ΔF508‐CFTR complexes with the co‐chaperone BAG3 that in addition appeared to co‐localize with the mutated protein on the cell surface. These results shed new light on ΔF508‐CFTR interactions with proteins of the chaperones/co‐chaperones system and could be useful in strategies for future medical treatments for CF. J. Cell. Physiol. 227: 3317–3323, 2012. © 2011 Wiley Periodicals, Inc.
Critical choices for modeling breast cancer in transgenic mouse models
Authors: Caligiuri Isabella , Rizzolio Flavio , Boffo Silvia , Giordano Antonio , Toffoli Giuseppe
Published: December 2011

Modeling breast cancer in the mouse has helped to better define the heterogeneity of human breast cancer. In the recent past, it has become evident that some limitations have restricted the potential benefits that can be achieved with this approach. In this review, we highlight some key points that should be taken into account when the mouse is used, with special emphasis on transgenic models. J. Cell. Physiol. 227: 2988–2991, 2012. © 2011 Wiley Periodicals, Inc.
BEYOND THE SUBSIDY: COYOTES, CREDIT AND FAIR TRADE COFFEE
Authors: Tedeschi Gwendolyn A. , Carlson Julie A.
Published: December 2011

International trade economists have largely avoided undertaking analysis of the fair trade movement because of the fact that fair trade is generally viewed as a price subsidy. Standard international trade models show this type of trade policy to be inefficient, as it would cause oversupply and further depress world prices. The problem with applying a standard international trade model to fair trade in coffee is that the input markets associated with coffee production are not perfectly competitive. Since perfect competition is an assumption common to many models of international trade, the conclusions of these models are not applicable in this setting. In this paper, we examine three models of coffee production. In the first model, the problem for coffee farmers is examined as if all markets were perfectly competitive; in the second model, we examine coffee production with an inefficient credit market in the absence of fair trade; and in the third model, we examine coffee production with an inefficient credit market but with the possibility of fair trade. Farmer welfare is improved with fair trade at the expense of local middlemen, but total welfare is lower than what could be achieved with perfect competition. Copyright © 2011 John Wiley & Sons, Ltd.
Liver‐vessel cancellation artifact on in‐phase and out‐of‐phase MRI imaging: A sign of ultra‐high liver fat content
Authors: Herédia Vasco , Ramalho Miguel , de Campos Rafael O.P. , Dale Brian , Azevedo Rafael , Woosley John T. , Semelka Richard C.
Published: December 2011

Purpose:

To describe a new MRI sign, the liver‐vessel cancellation artifact, on In‐Phase and Out‐of‐Phase gradient‐echo sequences related to ultra‐high liver fat content (>90%) by qualitative histology.

Materials and Methods:

Institutional review board approval was obtained for this retrospective HIPAA‐compliant study with waived informed consent. Patients with liver steatosis were searched in MRI (n = 195) and pathology (n = 116) databases between January 1, 2008, and June 20, 2010. Two readers blindly reviewed all MR images for the presence of the liver‐vessel cancellation sign. Cross‐reference of patients with biopsy‐proven steatosis and MRI within one month was performed (n = 54; 25 males, 29 females; mean age 41.0 ± 18.9), with a population of 6 patients with ultra‐high liver fat content (1 male, 5 females; mean age 15.5 ± 11.2). Performance diagnostic tests, including sensitivity and specificity, were performed.

Results:

Liver‐vessel cancellation sign was present in all patients with ultra‐high liver fat content but in none of the remaining patients. Calculated sensitivity and specificity for the detection of ultra‐high liver fat content with this sign were 100% (95% confidence interval [CI]: 69.1–100%) and 100% (95% CI: 98.4–100%), respectively.

Conclusion:

The presence of liver‐vessel cancellation artifact around intra‐hepatic vessels is a feature of ultra‐high liver fat content. J. Magn. Reson. Imaging 2012;35:1112‐1118. © 2011 Wiley Periodicals, Inc.
Analysis of a non‐structural gene reveals evidence of possible hepatitis C virus (HCV) compartmentalization
Authors: Blackard Jason T. , Ma Gang , Welge Jeffrey A. , Martin Christina M. , Sherman Kenneth E. , Taylor Lynn E. , Mayer Kenneth H. , Jamieson Denise J.
Published: December 2011

Viral diversity is a hallmark of hepatitis C virus (HCV) infection; however, only limited data are available regarding HCV variability in extrahepatic sites, and none have systematically compared diversity in non‐structural and structural genomic regions. Therefore, HCV diversity in the NS5B and envelope 1 (E1) hypervariable region 1 (HVR1) genes was evaluated in matched sera and peripheral blood mononuclear cells (PBMCs) obtained from 13 HCV‐infected women. Multiple clonal sequences were compared to evaluate quasispecies diversity and viral compartmentalization in PBMCs. Genetic distances were higher for E1/HVR1 compared to NS5B in both the sera and PBMCs (P = 0.0511 and 0.0284). Genetic distances were higher in serum NS5B compared to PBMC NS5B (P = 0.0003); however, they were not different when comparing E1/HVR1 in sera to PBMCs. By phylogenetic analysis of NS5B, evidence of possible PBMC compartmentalization was observed for one woman, while statistical methods were consistent with PBMC compartmentalization for six women. Evidence of compartmentalization within a non‐structural genomic region may suggest that viral adaptation to a unique extracellular microenvironment(s) may be required for efficient replication and could contribute to HCV persistence. J. Med. Virol. 84:242–252, 2012. © 2011 Wiley Periodicals, Inc.
Comprehensive analysis of the prevalence of hepatitis B virus escape mutations in the major hydrophilic region of surface antigen
Authors: Ma Qiang , Wang Yefu
Published: December 2011

Escape mutations in the major hydrophilic region (MHR) of hepatitis B surface antigen (HBsAg) are reported widely worldwide; these mutations lead to diagnostic problems, emergence of vaccine‐escape mutants, and hepatitis B immunoglobulin (HBIG) therapy failure. However, the prevalence of these mutations in different genotypes remains to be studied systematically. In the current study, 11,221 non‐redundant hepatitis B virus (HBV) sequences of 8 genotypes (from A to H), obtained from the National Center for Biotechnology Information (NCBI), were analyzed to determine the prevalence of HBsAg escape mutations that were previously described. Eight important mutations associated with diagnostic failure, P120T, T126S, Q129H, G130N, S143L, D144A, and G145A/R, were prevalent in one or more genotypes, with the frequency of no less than 1%. With regard to escape variants that evade vaccine or immunoglobulin therapy, mutations were located mainly at positions 120, 126, 129, 130, 133, 134, 137, 140, 143, 144, and 145. The majority of such mutations showed genotypic heterogeneity, indicating the different distribution of the escape mutations. Most of the escape mutations clustered in the “a” determinant, indicating that this region was more likely to be affected by immune selection or antiviral therapy than other regions. Understanding the prevalence and heterogeneity of escape mutations could provide useful guidance for the improvement of diagnostic assays, design of new vaccines, and prevention of failure of HBIG therapy. J. Med. Virol. 84:198–206, 2012. © 2011 Wiley Periodicals, Inc.
Sabin and wild polioviruses from apparently healthy primary school children in northeastern Nigeria
Authors: Baba M.M. , Oderinde B.S. , Patrick P.Z. , Jarmai M.M.
Published: December 2011

Despite significant success of the Global Polio Eradication Initiative (GPEI) in Nigeria, Afghanistan, India, Pakistan, wild poliovirus still occurs due to persistently high proportions of under and unimmunized children. The study aimed at determining the type of poliovirus often excreted into the environment. Four hundred nine fecal samples collected from apparently healthy school children aged 5–16 years in Borno and Adamawa States, northeastern Nigeria, were tested for poliovirus by tissue culture technique. The isolates were characterized further by intratypic differentiation testing and genetic sequencing. Three wild poliovirus type, 11 Sabin type, combination of Sabin‐types 1 + 2 and 2 + 3 poliovirus, and 22 non‐polio enteroviruses were obtained. The continued excretion of wild‐type poliovirus among children above 5 years old vaccinated with oral polio vaccine contributes to the persistent circulation of these viruses in the environment and may limit the population immunity. However, the excreted Sabin poliovirus is capable of immunizing the unvaccinated children and promotes herd immunity. Similarly, the excretion of combination of two polio serotypes indicates the child susceptibility to the missing serotype (s) and therefore indicates an immunity gap. The common unhygienic practices in the environment could aid the spread of these viruses through oral–fecal route. Asymptomatic transmission of wild poliovirus among older oral polio vaccine‐vaccinated children poses a serious threat to polio eradication program in Nigeria and therefore, environmental and serological surveillance with larger sample size are important for monitoring poliovirus circulation in Nigeria. J. Med. Virol. 84:358–364, 2012. © 2011 Wiley Periodicals, Inc.
Detection and molecular characterization of noroviruses and sapoviruses in children admitted to hospital with acute gastroenteritis in Vietnam
Authors: Trang Nguyen V. , Luan Le T. , Kim‐Anh Le T. , Hau Vu T.B. , Nhung Le T.H. , Phasuk Pimmnapar , Setrabutr Orntipa , Shirley Hannah , Vinjé Jan , Anh Dang D. , Mason Carl J.
Published: December 2011

Noroviruses (NoV) and sapoviruses (SaV) are recognized as important causes of acute gastroenteritis in children worldwide. In this study, the prevalence and genetic variability of NoV and SaV were determined in hospitalized children <5 years of age with acute gastroenteritis in Hanoi, Vietnam. A total of 501 fecal specimens collected between November‐2007 and October‐2008, that previously had been tested for rotavirus (RV), were tested for NoV and SaV by realtime RT‐PCR. Positive samples were genotyped by conventional RT‐PCR followed by sequencing. GII NoV was detected in 180 (36%) and SaV in 7 (1.4%) of the samples. NoV was detected year‐round ranging from 9.5% in April to 81.5% in September among RV negative samples. NoV GII.4 Minerva (2006b) was the dominant genotype (93%) with a few other genotypes detected including GII.3 (4.4%), GII.13 (1.7%), and GII.2 (0.6%) but no GI strains. Only GI and GII SaV strains were detected in this study. No difference in NoV prevalence between age groups was noted. Frequency of vomiting or fever was similar between children with NoV and RV infection, yet, NoV caused diarrhea with longer duration. In conclusion, NoV is the second most frequent cause of diarrhea in hospitalized children in North Vietnam. J. Med. Virol. 84:290–297, 2012. © 2011 Wiley Periodicals, Inc.
Detection of herpes simplex virus (1 and 2), varicella‐zoster virus, cytomegalovirus, human herpesvirus 6 and enterovirus in immunocompetent tunisian patients with acute neuromeningeal disorder
Authors: Nahdi Imen , Boukoum Hanen , Nabil Ben Salem Abid , Ben Romdane Fouad , Hammami Saber , Chebel Saber , Mahbouba Frih‐Ayed , Guediche Mohamed Neji , Chakroun Mohamed , Aouni Mahjoub , Imbert‐Marcille Berthe‐Marie , Bressollette‐Bodin Celine
Published: December 2011

Enteroviruses (EVs) and human herpesviruses (HHVs) are involved frequently in acute neurological disorders of viral etiology. This study aimed to investigate the incidence of herpes simplex virus types‐1 (HSV‐1) and 2 (HSV‐2), varicella‐zoster virus (VZV), cytomegalovirus (CMV), human herpesvirus 6 (HHV‐6) and human enteroviruses (EVs) in cerebrospinal fluid (CSF) samples of Tunisian immunocompetent patients with neuromeningeal disorders. The patients had been hospitalized at the Fattouma Bourguiba University Hospital (Monastir, Tunisia) between September 2007 and June 2009. At least one viral genome was detected in 58 (46%) out of 126 CSF samples collected. Enterovirus was detected in 31 of the positive samples (53.4%), CMV in 20 (34.5%), HSV‐1 in 3 (5.2%), HSV‐2 in 6 (10.3%), VZV in 4 (6.9%), HHV‐6 in 2 (3.4%). More than one viral genome was detected in seven CSF samples, including CMV DNA in six of the samples. The high frequency of enteroviral infections in aseptic meningitis was confirmed. The detection of CMV DNA only suggests a direct role of this virus in the etiology of acute neuromeningeal disorder. J. Med. Virol. 84:282–289, 2012. © 2011 Wiley Periodicals, Inc.
Mechanische Druckfortpflanzung in vulkanischen Aschenböden bei unterschiedlicher Bewirtschaftungsweise
Authors: Ellies Achim , Horn Rainer
Published: December 2011

Untersucht wurde die Druckfortpflanzung mit Hilfe von Druckmeßdosen in vulkanischen Aschenböden unter unterschiedlicher Nutzung in Südchile. Anhand der Ergebnisse von Befahrungsversuchen läßt sich feststellen, daß die vertikale Normalspannung in Naturwaldböden trotz sehr geringer Lagerungsdichte aufgrund der Verzahnung der Vulkanaschen und aufgrund des starken Wurzelfilzes im Oberboden weitestgehend kompensiert wird. Durch Waldrodung und nachfolgender zusätzlicher Befahrung mit Landmaschinen werden die ursprünglich sehr lockere, stabile Bodenstruktur zerstört und unter tiefen Spurrillen dichte Bodenplatten bis in größere Tiefe ausgebildet, die dann wieder zu einer Druckkompensierung beitragen. Eine nachträgliche Bodenlockerung führt zu einer sogar tieferreichenden Druckfortpflanzung in dem durch auflastabhängige Scherungen deformierten Boden, wobei während der Bodendeformation die meßbaren Drucke in den einzelnen Bodentiefen gering, aber gleichmäßig über größere Tiefen fortgepflanzt werden. Aus den erzielten Ergebnissen läßt sich ein erstes Bild über die Strukturentwicklung in Vulkanaschenböden und ihre Bedeutung für die Druckfortpflanzung ableiten.
Einfluß organischer Düngungen auf bodenphysikalische Parameter
Authors: Becher Hans H.
Published: December 2011

Die Wirkung einer 13jährigen, zusätzlichen Düngung mit Ernterückständen zu einer mineralischen Düngung oder Stallmistdüngung auf das Bodengefüge wurde untersucht. Auf der pseudovergleyten Parabraunerde aus Löß über tertiärem Feinsand in Oberbayern wurde Feldgemüse angebaut. U.a. wurden Eindringwiderstand, gesättigte Wasserleitfähigkeit (kf). Lagerungsdichte und Aggregatdichte, Porengrößenverteilung und Aggregatstabilität (AS) bestimmt. Die Düngung mit Ernterückständen und/oder Stallmist erhöhte den Gehalt der Krume an Corg. Dadurch wurden AS und kf erhöht, und zwar stärker durch Ernterückstände. Die übrigen Eigenschaften wurden nicht signifikant beeinflußt, weil diese Eigenschaften auch von Witterung und Bodenbewirtschaftung abhängen und damit Momentanwerte darstellen. Die nutzbare Feldkapazität wurde durch Düngung mit Ernterückständen um ca. 10 mm über 70 cm Profiltiefe erhöht.
Auswirkungen des Agroforestry‐Anbausystems auf den Mineralstickstoffgehalt und das Matrixpotential in einer Parabraunerde sowie das Wachstum von Acer Pseudoplatanus
Authors: Bohne Heike , Rauch Dirk
Published: December 2011

Es werden Ergebnisse von dreijährigen Untersuchungen in einem Agroforestry‐Anbausystem, hier bestehend aus Acer pseudoplatanus als Gehölzkultur kombiniert mit den Einsaaten “Klee” (Trifolium repens), “Weidelgras” (Lolium perenne) und “ohne Einsaat” (Herbizid), auf einer Parabraunerde aus Löß vorgestellt. Der Boden wurde in den vorangegangenen Jahren intensiv landwirtschaftlich genutzt. Bei der Variante “ohne Einsaat” kam es besonders im ersten Jahr nach der Nutzungsänderung, aber auch in den Folgejahren aufgrund der geringen und erst spät in der Vegetationsperiode einsetzenden N‐Entzüge durch die Gehölze zu Nitratauswaschungen. Die im Boden verbleibende Menge an Mineralstickstoff war für ein optimales Gehölzwachstum ausreichend. Mit der Einsaat von Gras konnte der Boden bereits im ersten Jahr nach der Nutzungsänderung weitgehend an Mineralstickstoff entleert werden, Auswaschungen traten jedoch in der Tiefe 60–90 cm ein. In den Folgejahren blieben die Mineralstickstoffgehalte des Bodens gering, waren aber für ein optimales Wachstum beider Kulturen nicht ausreichend. Die Wachstumsbedingungen für die Gehölze wurden zusätzlich durch die Wasserkonkurrenz des Grases beeinträchtigt. Bei der Einsaat von Klee lag als Folge der symbiontischen N‐Bindung und der anschließenden N‐Mineralisation der Mineralstickstoffgehalt über der Höhe der Entzüge. Optimales Wachstum der Gehölze und der Untersaat ist gewährleistet, es traten aber Auswaschungsverluste auf. Die auch unter Klee aufgetretenen hohen Wasserspannungen haben das Gehölzwachstum nicht beeinträchtigt. In allen drei Jahren kam es bei allen Varianten zu N‐Verlagerungen auch im zeitigen Frühjahr. Das Gehölzwachstum unterschied sich bisher nicht zwischen den Varianten “Herbizid” und “Klee” und war bei “Gras” deutlich geringer.
Palygorskitreicher Vertisol im ariden Bereich NO‐Somalias
Authors: Alaily Fayez
Published: December 2011

Im ariden Bereich NO‐Somalias kommen auf einer breiten Ebene im Zentralbereich des Darror‐Tals palygorskitreiche Vertisole vor. Der untersuchte Vertisol ist sehr arm an Smectit und Vermiculit. Das Ausgangsgestein dieses Bodens besteht aus pleistozänen fluviatilen Sedimenten, die aus tertiären Gesteinen stammen. Im Gelände zeigt der Boden “slicken sides” in 92 bis 140 cm Tiefe, sowie Schrumpfrisse, die eine Tiefe von mehr als 100 cm erreichen und nur z.T. mit Oberbodenmaterial gefüllt sind. Aufgrund des frisch aussehenden Gilgai‐Mikroreliefs und der z.T. leeren Schrumpfrisse dürfte die Peloturbation unter den heutigen Klimaverhältnissen aktiv sein. Der hohe Gehalt an Palygorskit in dem untersuchten Vertisol ist aufgrund der Ergebnisse als lithogen zu betrachten und stammt aus den tertiären Gesteinen der Umgebung.
Bedeutung der arbuskulären Mykorrhiza (AM) für die Schwermetalltoleranz von Luzerne (Medicago Sativa L.) und Hafer (Avena sativa L.) auf einem klärschlammgedüngten Boden
Authors: Ricken Barbara , Höfner Werner
Published: December 2011

In Gefäßversuchen mit einem klärschlammgedüngten Boden wurde der Einfluß der arbuskulären Mykorrhiza (AM) ‐Pilzisolate von Glomus sp. (T6 und D13) auf Pflanzenwachstum und Schwermetall (SM) ‐aufnahme von Luzerne (Medicago sativa L.) und Hafer (Avena sativa L.) untersucht. Das Wachstum von Luzerne wurde durch eine Mykorrhizierung nicht signifikant beeinflußt. Bei Hafer forderte eine AM‐Inokulation mit T6 das Wachstum von Wurzel und Sproß bis zu 70% bzw. 55%, zur Reife aber ergab sich gleicher Sproßertrag.

Die P‐Gehalte in Wurzel und Sproß von Luzerne wurden durch die AM gesteigert. Mykorrhizierte Luzerne zeigte sowohl in Wurzel als auch Sproß zumeist geringere Zn‐, Cd‐ und Ni‐Gehalte und Aufnahmen als die Kontrolle. Dabei wurde die Verlagerung der SM in den Sproß bei mykorrhizierten Pflanzen gefördert. Die Wurzellänge der Luzerne war infolge einer Mykorrhizierung zum Zeitpunkt der 1. Ernte geringfügig erhöht, zur 2. Ernte hingegen signifikant reduziert (bis zu 38%).

Bei Hafer bewirkte die Mykorrhiza eine bis zu 78% erhöhte Wurzellänge und gesteigerte Zn‐, Ni‐ und Cd‐Gehalte und Aufnahmen in Wurzel und teilweise auch im Sproß. Die Verlagerung der SM in den Sproß mykorrhizierter Pflanzen wurde aber gehemmt. Dies läßt eine Bindung der SM in den AM‐Strukturen in der Wurzel vermuten.

Die Ergebnisse deuten auf eine Filterfunktion der Mykorrhiza gegenüber SM im Boden hin, die bei den verschiedenen Pflanzenarten auf unterschiedlichen Mechanismen zu beruhen scheint.
Differential effects of potassium and molybdenum deficiency and fertilization on nitrogen metabolism in Norway spruce (Picea abies)
Authors: Weidner Manfred , Brückner Helmut , Pajak Eva , Schmidt Brigitte , Wichtmann Hubert
Published: December 2011

A field study on mineral nutrition of 12 year old Norway spruce (Picea abies (L.) Karst.) was carried out on a Lower Triassic region in the Eifel mountains in a plantation where the juvenile trees exhibited marked visual differences on adjacent plots, thus indicating a patchy pattern concerning the fertility status of the soil. This was confirmed by geological, pedological and chemical analyses, including X‐ray diffraction analyses of the clay minerals and soil water as well as needle element analyses. A combined K and N deficiency was diagnosed for those trees, which exhibited growth retardation and small, rigid, and yellowish‐green needles. Chlorophyll and protein content and glutamine synthetase activity were reduced while triphenyltetrazoliumchloride (TTC) reduction was enhanced in the sick trees as compared to adjacent healthy looking trees of the same age and provenance. A diagnostic fertilization treatment with K and Mo, respectively, yielded the following results. One year after administration of Mo a marked increase in total N content of the needles was observed, due to an increase of the storage pools for soluble (nonprotein) nitrogen, namely the basic amino acids arginine, histidine and lysine and also of ornithine. Yet, no visual recovery of the trees was observed. On the other hand, K fertilization caused an improvement of all biochemical parameters, except protein content and soluble N storage pools. The relationships between Mo dependent nitrate reduction, potassium content and nitrogen metabolism are discussed.
Changes of redox and pH conditions in a flooded soil amended with glucose and manganese oxide or iron oxide under laboratory conditions
Authors: Glinski Jan , Stahr Karl , Stepniewska Zofia , Brzezinska Malgorzata
Published: December 2011

The changes of Eh and pH in soil suspension (Ah‐horizon of a Mollic Gleysol) and Mn2+ or Fe2+ concentrations in the equilibrium soil solution at different levels of glucose (0%, 0.5% and 1%) and MnO2 (0%, 0.025%, 0.05% and 0.1%) or Fe2O3 (0%, 0.025%, 0.05% and 0.1%) were examined. It was found that the degree of Mn‐ and Fe‐reduction in soil depends mainly on the presence and the amount of an easily decomposable carbon source and to a minor degree on the content of native or added forms of MnOO2 or Fe2O3 in the soil.

Theoretical relationships between the water soluble manganese and iron and the Eh and pH values have been verified, when the observed initial drop of Eh was eliminated. It was found that the water soluble manganese content was described best by the Mn2O3/Mn2+ redox system, and that of iron by the Fe3 (OH)3/Fe2+ system.
Entwicklung der Niederschlags‐Deposition von Schwermetallen in West‐Deutschland. 1. Blei und Cadmium
Authors: Schulte Andreas , Balazs Arpad , Block Joachim , Gehrmann Joachim
Published: December 2011

Auf 25 Meßflächen in 4 Bundesländern Deutschlands wurde von 1984 bis 1993 die Deposition von Blei und Cadmium mit dem Niederschlag gemessen. Die absolute Höhe der Deposition von Blei und Cadmium schwankt in Abhängigkeit vom Standort und der jährlichen Niederschlagshöhe bzw. Emission.

Auf allen untersuchten Meßflächen nimmt die Blei‐Deposition mit dem Niederschlag im Beobachtungszeitraum signifikant ab. Im Durchschnitt aller untersuchten Meßflächen verringerte sich die Blei‐Deposition mit dem Niederschlag von 142 g ha−1 im Jahr 1984 auf 31 g ha−1 im Jahr 1993 (r = −0.934***). Die Abnahme der Blei‐Deposition entspricht der prognostizierten Abnahme der Blei‐Emission in Deutschland im gleichen Zeitraum insbesondere in Folge der Einführung unverbleiter Kraftstoffe im Jahre 1984.

Im Durchschnitt aller Meßflächen nahm die Cadmium‐Deposition von 3.4 g ha−1 im Jahr 1984 auf 2.0 g ha−1 ab (r=‐0.900***). Eine signifikante Abnahme der Cadmium‐Deposition konnte jedoch im Gegensatz zum Blei nur an 11 von 25 Meßstationen beobachtet werden. Die relative Abnahme der Cadmium‐Deposition mit dem Niederschlag ist wesentlich geringer als die prognostizierte Emissionsminderung von Cadmium im etwa gleichen Zeitraum.
Effect of potassium application on the transformation of zinc fractions in soil and on the zinc nutrition of wetland rice
Authors: Mandal Biswapati , Pattanayak P. S. Das , Samanta A. , Chatterjee A. K.
Published: December 2011

The effect of different levels of K application on the transformation of native as well as applied Zn fractions in a rice‐growing soil was studied under two moisture regimes viz. waterlogged and alternate waterlogged and saturation. Application of K caused an increase in the water‐soluble plus exchangeable, organically complexed and carbonates, and other acid‐soluble mineral fractions of native soil Zn. Application of K also caused an increase in the transformation of applied Zn into all the above three fractions of the element in soil. The above effects of K were more pronounced in soil under waterlogged than under alternate waterlogged and non‐waterlogged moisture regimes.

The results of a greenhouse experiment showed that K application caused an increase in Zn uptake and per cent utilization of both native and added Zn by rice. This was attributed to the increase in the water‐soluble plus exchangeable and organically complexed forms of Zn in soil due to K application.
Schätzung der Denitrifikation in landwirtschaftlich genutzten Böden. I. Grundlagen
Authors: Hermsmeyer Dirk , Van Der Ploeg Rienk R.
Published: December 2011

Das Datenmaterial eines vom Bundesministerium für Forschung und Technologie in den Jahren 1988–1992 geförderten Forschungsvorhabens über den Nitratumsatz unterhalb der Wurzelzone in einem landwirtschaftlch genutzten Trinkwassereinzugsgebiet wurde analysiert. Ziel der Analyse war die Entwicklung eines Verfahrens zur Abschätzung der Denitrifikation in den Böden des Untersuchungsgebietes. Das vorhandene Datenmaterial wurde durch eigene Feld‐ und Labormessungen ergänzt. Mit Hilfe des erweiterten Datenmaterials wurde ein semi‐quantitatives Punktbewertungsverfahren zur Abschätzung der Denitrifikation entwickelt. Als Eingabegrößen werden für das Schätzverfahren die folgenden Bodenkenngrößen benötigt: Menge und C/N‐Verhältnis der organischen Substanz, Bodenart, Bodengefüge, Lagerungsdichte, Porosität, Feldkapazität, Luftkapazität, Grundwasserflurabstand und pH‐Wert. Zusätzlich werden im Schätzverfahren das Wärmeregime und die Durchlüftung des Bodenprofils berücksichtigt. Da über diese beiden Bodeneigenschaften keine Meßdaten Vorlagen, wurden die benötigten Daten errechnet. In der vorliegenden Arbeit werden die Entwicklung des Schätzverfahrens und die Erhebung der notwendigen Daten besprochen. In einer zweiten Arbeit werden anschließend die mit dem Schätzverfahren erzielten Ergebnisse diskutiert.
Schätzung der Denitrifikation in landwirtschaftlich genutzten Böden. II. Ergebnisse und Bewertung
Authors: Hermsmeyer Dirk , Van Der Ploeg Rienk R.
Published: December 2011

Das in Teil 1 beschriebene Verfahren wird im vorliegenden Beitrag zur Bewertung der relativen potentiellen Denitrifikation an den Untersuchungsstandorten genutzt. Die erhaltenen maximalen potentiellen Denitrifikationsraten dieser Standorte werden auf die Verbreitungsareale der Bodentypen im Untersuchungsgebiet regionalisiert. Schlagspezifische Schätzwerte aktueller Denitrifikationsraten werden durch die Berücksichtigung von Daten zum Stickstoffhaushalt der landwirtschaftlich genutzten Flächen erhalten.

Das Schätzmodell ergibt Denitrifikationsraten von < 10 kg N/(ha·a) für die sandigen Braunerden und Braunerde‐Gleye des Untersuchungsgebietes, in denen die günstigste Kombination der Einflußfaktoren im Sinne geringer Denitrifikationsverluste angetroffen wurde. Hohe Verluste bis 50 kg N/(ha·a) sind in Niedermooren, Auenböden und Gleyen zu erwarten, die durch hohe Gehalte organischer Substanz und geringe Flurabstände des Grundwassers gekennzeichnet sind. Schluffige Parabraunerden und Plaggenesche nehmen eine mittlere Stellung ein; die potentiellen Stickstoffverluste dieser Böden durch Denitrifikation werden auf 20 bis 35 kg N/(ha·a) geschätzt. Diese Werte erscheinen aufgrund einer Plausibilitätskontrolle an Daten der Anionenkonzentration an der Grundwasseroberfläche realistisch; eine Eichung des Schätzmodells steht jedoch bislang aus.
Cadmiumverfügbarkeit für Gemüsepflanzen in Kleingartenböden
Authors: Heymann Hardy , Wiechmann Horst
Published: December 2011

Zur Ermittlung der Mobilität und Pflanzenverfügbarkeit von Cadmium im Boden wurden umfangreiche Gefäßversuche mit unterschiedlichem, unmittelbar Hamburger Kleingärten entstammendem Bodenmaterial und verschiedenen Gemüsearten durchgeführt. Es wurden die Cd‐Gesamtgehalte der Böden in Kombination mit anderen Bodeneigenschaften sowie die mit 0.1 M CaCl2 und I M NH4NO3 extrahierbaren Cd‐Gehalte der Böden im Hinblick auf die Prognosemöglichkeit der Cd‐Aufnahme von Pflanzen überprüft. Dabei stand ein direkter Methodenvergleich zwischen der CaCI2− und der NH4NO3−Extraktion im Vordergrund. Aus den Verfügbarkeitsuntersuchungen wurden Bodenschwellenwerte für die Cd‐Aufnahme in die Pflanzen abgeleitet, oberhalb derer Überschreitungen der momentan gültigen Lebensmittelrichtwerte für Cd in der Pflanze wahrscheinlich sind. Die Schwellenwerte wurden alternativ für die drei Untersuchungsmethoden Cd‐Gesamtgehalt in Kombination mit dem pH‐Wert sowie Cd‐Gehalt des 0.1 M CaCl2− und des 1 M NH4NO3−Lösungsextraktes aufgestellt.
Anwendung des Agrarökosystemmodells EPIC zur Prognose des Wasser‐ und Nährstoffhaushaltes von landwirtschaftlich genutzten Flächen auf Sandböden in Ost‐Brandenburg
Authors: Wegehenkel Martin
Published: December 2011

Die Anwendungsmöglichkeiten des Agrarökosystemmodells EPIC auf grundwasserfernen Sandböden der Grundmoränenlandschaft in Ost‐Brandenburg wurden mit Hilfe von Testrechnungen überprüft. Hierzu wurden mehrjährige Witterungsdaten und Meßreihen von Bodenfeuchte. Nitratgehalt im Boden, oberirdischer Biomasse und Kornerträgen von 2 Feldversuchsflächen herangezogen. Diese Messungen wurden zur Prüfung der Simulationsgüte des Modells mit den entsprechenden Resultaten von EPIC verglichen. Dabei zeigte sich bei der Bodenfeuchte eine gute Übereinstimmung von gemessenen und berechneten Werten. Bei der Simulation des Pflanzenwachstums war trotz der ebenfalls guten Korrelation zwischen gemessenen und simulierten Biomassen eine Unterschätzungstendenz zu Beginn der Wachstumsphase im Früfyahr und eine Überschätzungstendenz gegen Ende der Vegetationsperiode zu erkennen. Bei den Kornerträgen war ein Überschätzungstrend des Modells zu verzeichnen. Der Vergleich gemessener und simulierter Boden‐Nitrat‐Gehalte zeigte keine gute Übereinstimmung. Eine mögliche Ursache dafür ist die auf Langzeitsimulationen ausgerichtete Prozeßbeschreibung für den N‐Haushalt in EPIC. Ein weiterer Grund könnte der Umstand sein, daß die vom Modell berechneten N‐Aufnahmen der Pflanzen im Vergleich zu überschlägigen N‐Bedarfsberechnungen auf der Basis der simulierten Kornerträge zu hoch erscheinen. Letztlich konnte jedoch eine eindeutige Ursache für die unbefriedigende Übereinstimmung zwischen gemessenen und berechneten Boden‐Nitrat‐Gehalten im Rahmen dieser Studie nicht gefunden werden. Hier müssen noch weitere Analysen von EPIC in den Bereichen Mineralisation, N‐Aufnahme der Pflanzen und N‐Auswaschung erfolgen.
Soil chemical properties affecting NH4+ sorption in forest soils
Authors: Matschonat Gunda , Matzner Egbert
Published: December 2011

Fourteen European forest soils from the boreal to the mediterranean climate on different parent materials were investigated with respect to their ability to store NH4+ in exchangeable form, using sorption isotherms. Distribution coefficients for NH4+ sorption per unit weight of soil were in the range of 0.02 to 0.77. NH4+ sorption coefficients were usually highest in the forest floor of a given soil.

NH4+ sorption behaviour of mineral soil horizons was correlated to soil parameters that are determined during routine soil analysis. A combination of CEC and base saturation explained up to 95% of the variability Of NH4+ sorption. In the forest floors, variability in NH4+ sorption could not be explained quantitatively from independent soil parameters. The affinity of the sorption sites for NH4+ was the most important factor for explanation of the variability in NH4+ sorption in the forest floors but was of low importance in mineral soil horizons.

As NH4+ exchanges predominantly base cations, susceptibility of NH4+ to transport through the soil profile increases with Iowbase saturation of a soil as well as with low CEC values.
Verlagerung und Dispersion von Chlorid‐, Bromid‐, Nitrat‐ und SulfatTracern in zwei typischen Auenböden
Authors: Schlüter Wilhelm , Hennig Achim , Brümmer Gerhard W.
Published: December 2011

Auf zwei schwach bis mäßig sauren Auenböden wurden Chlorid, Bromid, Nitrat und Sulfat als Tracer appliziert. Neben der Gewinnung von Bodenlösungen mit Hilfe von keramischen Saugkerzen bis in 180 cm Tiefe erfolgte an ausgewählten Terminen eine Entnahme von Bodenproben zur Herstellung von Bodensättigungsextrakten. Die Konzentrationen des nicht sorbierten Chlorids, Bromids und Nitrats stimmten in den Saugkerzenlösungen und Bodensättigungsextrakten weitgehend überein, während die Konzentrationen des schwach sorbierten Sulfats z.T. erhebliche Abweichungen aufwiesen. Saugkerzenlösungen und Bodensättigungsextrakte erfassen damit offenbar in Böden saurer Reaktion unterschiedliche Fraktionen des gelösten Sulfats.

Aus dem Vergleich der zur selben Zeit in unterschiedlichen Profiltiefen auftretenden Verlagerungspeaks von Sulfat mit denen von Chlorid bzw. Bromid oder Nitrat ließ sich für den Ap‐Horizont einer Auenbraunerde ein Kd‐Wert von 0.16 1/kg und für den Bereich unterhalb von 30 cm ein Kd‐Wert von 0.02 1/kg errechnen.

Durch Variation der Dispersivität und Anpassung der mit dem Simulationsmodell DELPHI für verschiedene Untersuchungstermine errechneten Stoff‐Tiefenverteilungen an die erhaltenen Meßwerte konnten für die einzelnen Horizonte der untersuchten Böden Disper‐ sivitäten geschätzt werden. Diese nehmen Werte von 1.0 cm im Ap‐Horizont sowie 1.8 und 10.0 cm in den Unterbodenhorizonten an.
Estimating dissolved organic carbon in natural waters by UV absorbance (254 nm)
Authors: Brandstetter Anton , Sletten Ronald S. , Mentler Axel , Wenzel Walter W.
Published: December 2011

A close correlation exists between dissolved organic carbon (DOC) concentration and UV absorbance at 254 nm (A254) in natural waters. DOC and A254 were measured for soil solutions, throughfall, stemflow, and surface waters collected from a forested site located in eastern Austria. The slopes of lines determined by linear regression of DOC versus UV absorbance were very similar to those determined for wet deposition and throughfall samples collected in Nordrhein‐Westfalen, Germany by Bartels (1988). The intercept of the regression line in the current study indicates that approximately 1 mg L1 of non‐UV‐absorbing DOC is present; it is suggested that this is due to saturated aliphatic compounds such as acetate or formate.
Interaction between microbial biomass and activity and the soil chemical conditions and the processes of acid load in coniferous forest soils
Authors: Raubuch Markus , Beese Friedrich
Published: December 2011

The primary aims of the present investigation were to determine the proportion of microbial driven soil processes associated with acidification in coniferous forest soils, and the response of microbial communities with respect to soil acidification and to acidification processes. Lysimeters containing undisturbed soil columns from five forest sites in Europe were installed in a spruce forest in the Soiling (northern Germany) and exposed to the same input and climatic conditions. In the present study root uptake was excluded.

Under these conditions, during the 21 months of the experiment, acid load by microbial N‐transformations especially mineralization and subsequent nitrification were the most important processes ranging from 50.2% to 79.1%. Except for one soil the balances showed, that increasing levels of soil acidity decreased the potential of mineralization. This agreed with the observation that microbial biomass Cmic decreased. The biomass Cmic (kg ha−1 a−1) was significantly correlated to N‐output. The caloric quotient qW increased parallel to decreasing pH.

During the experiment the PH in all mineral soil horizons decreased significantly. This change in soil chemical conditions did not affect the microbial biomass Cmic but the caloric quotient increased during the experiment, especially in the upper mineral soil.
Enhanced calcium uptake in micropropagated potato plantlets by macroelement dilution
Authors: Abdulnour Jihad E. , Donnelly Danielle J. , Barthakur Nayana N.
Published: December 2011

Ca deficiency disorders are common in micropropagated plantlets but little is known regarding the uptake of Ca in vitro. Ca uptake by in vitra‐grown potato (Solanum tuberosum L. cvs. Bintje and Norland) plantlets was investigated when Ca levels were maintained but the total macroelement salts or just NH4, the major competing cation, were reduced in Murashige and Skoog (MS) medium. This increased the ratio of Ca:cations or Ca:NH4 as well as the osmotic potential of the medium. The increased Ca‐cations improved Ca uptake of shoot tips, leaves, and stems while increased Ca:NH4 had no effect. MS medium macroelement dilution may improve Ca uptake by micropropagated plantlets and prevent Ca deficiency disorders.
Microbial biomass C‐ and N‐dynamics in grassland soils amended with liquid manure
Authors: Kleber Markus , Jian‐Ping Hong , Stahr Karl
Published: December 2011

Turnover and fluxes of C and N through microbial biomass were investigated on a research site in the grassland region of southwestern Germany. For a period of twelve months, biomass C was determined every 2 weeks and biomass N every 4 weeks (Fumigation‐Extraction). This was done at fertilized plots as well as on plots, which had not been fertilized for eight years. Biomass C and N accounted for 1.5–7.5% of the soil C and 2–9% of the soil nitrogen. Unfertilized plots contained more biomass C and N than fertilized plots. No seasonal influence on the amount of the microbial biomass was visible. C/N ratios were not related to fertilization events. An increase of the C/N ratio with depth suggests a dominance of fungi in the subsurface horizons.

Estimates of biomass C and N turnover were calculated by dividing the total measured losses of biomass by the average quantity of biomass present (McGill et al., 1986), annual fluxes of carbon and nitrogen were calculated by dividing annual mean C(N) by the average C(N) in biomass (Jenkinson and Ladd, 1981). Average turnover rates for biomass C varied between 1.4 and 4.5 a−1, turnover rates for nitrogen were slower (1.2–3.3 a−1). Carbon Ruxes through the microbial biomass range from 5000 to 8000 kg ha−1 a−1, while nitrogen fluxes range from 400 to 700 kg ha−1 a−1.