@inproceedings{KellerReckliesRisiusetal.2023, author = {Keller, M and Recklies, R and Risius, H and R{\"o}pert, C and Menacho, Z and Kramer, Eckart}, title = {Rahmenkonzept f{\"u}r die Ber{\"u}cksichtigung der menschlichen Arbeitskraft bei der Ermittlung des Product Cabon Footprint (PCF) in landwirtschaftlichen Wertsch{\"o}pfungsketten}, series = {One Step Ahead - einen Schritt voraus! : Beitr{\"a}ge zur 16. Wissenschaftstagung {\"O}kologischer Landbau : Frick, 7. bis 10. M{\"a}rz 2023}, booktitle = {One Step Ahead - einen Schritt voraus! : Beitr{\"a}ge zur 16. Wissenschaftstagung {\"O}kologischer Landbau : Frick, 7. bis 10. M{\"a}rz 2023}, editor = {Bibic, Vanessa and Schmidtke, Knut}, publisher = {Verlag Dr. K{\"o}ster}, isbn = {978-3-96831-055-8}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-7122}, pages = {686 -- 687}, year = {2023}, language = {de} } @inproceedings{RisiusRoepertReckliesetal.2023, author = {Risius, H and R{\"o}pert, C and Recklies, R and Herfurth, P and Kramer, Eckart}, title = {M{\"o}glichkeiten und Grenzen einer Foodshed-Analyse zur Absch{\"a}tzung des Selbstversorgungsgrads in der Region Berlin-Brandenburg}, series = {One Step Ahead - einen Schritt voraus! : Beitr{\"a}ge zur 16. Wissenschaftstagung {\"O}kologischer Landbau : Frick, 7. bis 10. M{\"a}rz 2023}, booktitle = {One Step Ahead - einen Schritt voraus! : Beitr{\"a}ge zur 16. Wissenschaftstagung {\"O}kologischer Landbau : Frick, 7. bis 10. M{\"a}rz 2023}, editor = {Bibic, Vanessa and Schmidtke, Knut}, publisher = {Verlag Dr. K{\"o}ster}, isbn = {978-3-96831-055-8}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-7132}, pages = {688 -- 689}, year = {2023}, language = {de} } @article{HorfBoeneckeGebbersetal., author = {Horf, Michael and B{\"o}necke, Eric and Gebbers, Robin and Kling, Charlotte and Kramer, Eckart and R{\"u}hlmann, J{\"o}rg and Schr{\"o}ter, Ingmar and Schwanghart, Wolfgang and Vogel, Sebastian}, title = {Utility of visible and near-infrared spectroscopy to predict base neutralizing capacity and lime requirement of quaternary soils}, series = {Precision Agriculture}, volume = {24}, journal = {Precision Agriculture}, number = {1}, publisher = {Springer US}, issn = {1385-2256}, doi = {10.1007/s11119-022-09945-9}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-9257}, pages = {288 -- 309}, abstract = {AbstractDetailed knowledge of a soil's lime requirement (LR) is a prerequisite for a demand-based lime fertilization to achieve the optimum soil pH and thus sustainably increasing soil fertility and crop yields. LR can be directly determined by the base neutralizing capacity (BNC) obtained by soil-base titration. For a site-specific soil acidity management, detailed information on the within-field variation of BNC is required. However, soil-base titrations for BNC determination are too laborious to be extensively applied in routine soil testing. In contrast, visible and near-infrared spectroscopy (visNIRS) is a time and cost-effective alternative that can analyze several soil characteristics within a single spectrum. VisNIRS was tested in the laboratory on 170 air-dried and sieved soil samples of nine agricultural fields of a quaternary landscape in North-east Germany predicting the soil's BNC and the corresponding lime requirement (LRBNC) at a target pH of 6.5. Seven spectral pre-processing methods were tested including a new technique based on normalized differences (ND). Furthermore, six multivariate regression methods were conducted including a new method combining a forward stagewise subset selection algorithm with PLSR (FS-PLSR). The models were validated using an independent sample set. The best regression model for most target variables was FS-PLSR combined with the second Savitzky-Golay derivation as pre-processing method achieving R2s from 0.68 to 0.82. Finally, the performance of the direct prediction of LRBNC (R2 = 0.68) was compared with an indirect prediction that was calculated by the predicted BNC parameters. This resulted in slightly higher correlation coefficients for the indirect method with R2 = 0.75.}, subject = {-}, language = {en} } @article{NaglerSchweflerKaethneretal., author = {Nagler, Linda and Schwefler, Jana and K{\"a}thner, Jana and Giebel, Antje and Kramer, Eckart}, title = {Der Einfluss der Fahrgassenpflege auf das Mikroklima in Schwarzen Johannisbeeren (Ribes nigrum L.)}, series = {Erwerbs-Obstbau}, volume = {65}, journal = {Erwerbs-Obstbau}, number = {4}, publisher = {Springer Berlin Heidelberg}, issn = {0014-0309}, doi = {10.1007/s10341-022-00771-x}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-9269}, pages = {1035 -- 1046}, abstract = {Zusammenfassung Das Ziel der Untersuchung war es, den Einfluss der Fahrgassenpflegefrequenz auf die Lufttemperatur und die relative Luftfeuchte in Plantagen mit Schwarzen Johannisbeeren ( Ribes nigrum  L.) zu ermitteln. In der Praxis dient das Kurzhalten des Fahrgassenbewuchses als angewandte und pr{\"a}ventive Methodik, um die Durchl{\"u}ftung im Bestand zu verbessern und den Krankheitsdruck zu senken. Die On-Farm-Versuche fanden auf zwei {\"o}kologisch gef{\"u}hrten Strauchbeerenbetrieben in Brandenburg (Weggun und Sch{\"o}neiche) {\"u}ber einen Zeitraum von M{\"a}rz bis Juni 2021 statt. Die Einfl{\"u}sse der Pflegefrequenz auf das Mikroklima in den Fahrgassen wurden f{\"u}r praxis{\"u}bliche Mahdfrequenz („business as usual", BAU) und erh{\"o}hte Mahdfrequenz (TEST) ermittelt. Die Ergebnisse zeigen, dass mit einem kontinuierlichen Kurzhalten der Fahrgassen eine nachweisbare Beeinflussung auf die bodennahe Lufttemperatur und Luftfeuchte stattfindet. Dabei f{\"u}hrte eine erh{\"o}hte Mahdfrequenz (TEST) teils zu einer signifikant h{\"o}heren mittleren Lufttemperatur als in praxis{\"u}blicher Pflege (BAU), wohingegen die mittlere relative Luftfeuchte signifikant geringer war. Die Effekte waren abh{\"a}ngig vom Zeitpunkt und vom Standort. {\"U}ber die Versuchsperiode konnten maximale mittlere Lufttemperaturdifferenzen von 1,14 °C (Standort Weggun) bzw. 1,96 °C (Standort Sch{\"o}neiche) sowie maximale mittlere relative Luftfeuchtedifferenzen von 3,69 \% (Standort Weggun) bzw. 3,90 \% (Standort Sch{\"o}neiche) zwischen den Varianten TEST und BAU festgestellt werden. Vor allem in der Plantage mit dem geringeren Reihenabstand tritt dieser Effekt deutlicher auf. Die Ergebnisse lassen vermuten, dass die Plantagenstruktur einen Einfluss auf die Effekte hat, was in zuk{\"u}nftigen Versuchen untersucht werden sollte.}, subject = {-}, language = {de} } @article{VogelEmmerichSchroeteretal., author = {Vogel, Sebastian and Emmerich, Katja and Schr{\"o}ter, Ingmar and B{\"o}necke, Eric and Schwanghart, Wolfgang and R{\"u}hlmann, J{\"o}rg and Kramer, Eckart and Gebbers, Robin}, title = {The effect of soil moisture content and soil texture on fast in situ pH measurements with two types of robust ion-selective electrodes}, series = {SOIL}, volume = {10}, journal = {SOIL}, number = {1}, publisher = {Copernicus Publications}, address = {G{\"o}ttingen, Germany}, issn = {2199-398X}, doi = {10.5194/soil-10-321-2024}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-9377}, pages = {321 -- 333}, abstract = {Abstract In situ soil pH measurements with ion-selective electrodes (ISEs) are receiving increasing attention in soil mapping for precision agriculture as they can avoid time-consuming sampling and off-site laboratory work. However, unlike the standard laboratory protocol, in situ pH measurements are carried out at lower and varying soil moisture contents (SMCs), which can have a pronounced effect on the sensor readings. In addition, as the contact with the soil during in situ measurements should be relatively short, effects of soil texture could be expected because texture controls the migration of protons to the electrode interface. This may be exacerbated by the fact that the electrodes used for in situ measurements are made of less sensitive but more robust materials as compared to the standard glass electrode. Therefore, the aim of the present study was to investigate the effect of soil moisture and soil texture on pH measurements using robust antimony and epoxy-body ISEs pressed directly into the soil for 30 s. The SMC was gradually increased from dry conditions to field capacity. A wide range of soil texture classes were included, with sand, silt, and clay contents ranging from 16 \% to 91 \%, 5 \% to 44 \%, and 4 \% to 65 \%, respectively. An exponential model was fitted to the data to quantify the relationship between SMC and pH. The results show that an increase in SMC causes a maximum increase in pH of approximately 1.5 pH units, regardless of the type of pH ISE used. Furthermore, for sandy soil textures, a rather linear relationship between pH and SMC was observed, whereas, with decreasing mean particle diameter (MPD), the model had a pronounced exponential shape, i.e., a greater pH increase at low SMC and a plateau effect at high SMC. With increasing SMC, the pH values asymptotically approached the standard pH measured with a glass electrode in 0.01 M CaCl 2(soil : solution ratio of 1:2.5). Thus, at high SMC, subsequent calibration of the sensor pH values to the standard pH value is negligible, which may be relevant for using the sensor pH data for lime requirement estimates. The pH measurement error decreases exponentially with increasing soil moisture and increases with decreasing MPD. Using a knee point detection, reliable pH values were obtained for SMC  > 11 \%, irrespective of the pH ISE used. An analysis of the regression coefficients of the fitted exponential model showed that the maximum pH increase also depends on soil texture; i.e., the influence of soil moisture variation on the pH value increases with decreasing MPD. Moreover, the concavity of the exponential curve increases with decreasing MPD.}, subject = {-}, language = {en} } @article{SchmidingerSchroeterBoeneckeetal., author = {Schmidinger, Jonas and Schr{\"o}ter, Ingmar and B{\"o}necke, Eric and Gebbers, Robin and Ruehlmann, Joerg and Kramer, Eckart and Mulder, Vera L. and Heuvelink, Gerard B. M. and Vogel, Sebastian}, title = {Effect of training sample size, sampling design and prediction model on soil mapping with proximal sensing data for precision liming}, series = {Precision Agriculture}, volume = {25}, journal = {Precision Agriculture}, number = {3}, publisher = {Springer US}, address = {New York}, issn = {1385-2256}, doi = {10.1007/s11119-024-10122-3}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-9484}, pages = {1529 -- 1555}, abstract = {Abstract Site-specific estimation of lime requirement requires high-resolution maps of soil organic carbon (SOC), clay and pH. These maps can be generated with digital soil mapping models fitted on covariates observed by proximal soil sensors. However, the quality of the derived maps depends on the applied methodology. We assessed the effects of (i) training sample size (5-100); (ii) sampling design (simple random sampling (SRS), conditioned Latin hypercube sampling (cLHS) and k-means sampling (KM)); and (iii) prediction model (multiple linear regression (MLR) and random forest (RF)) on the prediction performance for the above mentioned three soil properties. The case study is based on conditional geostatistical simulations using 250 soil samples from a 51 ha field in Eastern Germany. Lin's concordance correlation coefficient (CCC) and root-mean-square error (RMSE) were used to evaluate model performances. Results show that with increasing training sample sizes, relative improvements of RMSE and CCC decreased exponentially. We found the lowest median RMSE values with 100 training observations i.e., 1.73\%, 0.21\% and 0.3 for clay, SOC and pH, respectively. However, already with a sample size of 10, models of moderate quality (CCC > 0.65) were obtained for all three soil properties. cLHS and KM performed significantly better than SRS. MLR showed lower median RMSE values than RF for SOC and pH for smaller sample sizes, but RF outperformed MLR if at least 25-30 or 75-100 soil samples were used for SOC or pH, respectively. For clay, the median RMSE was lower with RF, regardless of sample size.}, subject = {-}, language = {en} } @article{RuehlmannBoeneckeGebbersetal., author = {Ruehlmann, Joerg and B{\"o}necke, Eric and Gebbers, Robin and Gerlach, Felix and Kling, Charlotte and L{\"u}ck, Katrin and Meyer, Swen and Nagel, Anne and Palme, Stefan and Philipp, Golo and Scheibe, Dirk and Schr{\"o}ter, Ingmar and Vogel, Sebastian and Kramer, Eckart}, title = {Predicting the Base Neutralization Capacity of Soils Based on Texture, Organic Carbon and Initial pH: An Opportunity to Adjust Common Liming Recommendation Approaches to Specific Management and Climate Conditions}, series = {Agronomy}, volume = {13}, journal = {Agronomy}, number = {11}, editor = {Ciavatta, Claudio}, publisher = {MDPI}, issn = {2073-4395}, doi = {10.3390/agronomy13112762}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:eb1-opus-9435}, abstract = {

Liming is an effective measure to increase the soil pH and to counterbalance soil acidification. Therefore, the liming recommendations (LRs) for agricultural practice consider two aspects: changing the initial pH to the desired pH and compensating for all pH decreases taking place within the liming interval. The separation of these aspects is essential to optimize LRs and to minimize lime losses to the environment. Therefore, we developed a pedotransfer function (PTF) to calculate the lime demand to change the initial pH to the desired pH and compared the results with the LRs for agricultural practice. Applying this PTF to a set of 126 soil samples that were analyzed for base neutralization capacity could explain approximately 78\% of the variability in the pH changes after the addition of different amounts of Ca(OH)2. Consequently, the lime demand to change the initial pH to the desired pH increased by approximately one-sixth compared to the lime demand proposed by the liming recommendation scheme, which is commonly used in Germany. From the numerical difference between the lime demand according to the LRs and the PTF, we calculated the annual acidification rates based on the soil texture, organic matter content and initial pH. Decoupling the abovementioned two aspects of LRs might be helpful to optimize the LRs by adapting to different regions, diverse management strategies and a changing climate.

}, subject = {-}, language = {en} }