Haplotype-resolved genome analyses of a heterozygous diploid potato
Zhou, Qian ; Tang, Dié ; Huang, Wu ; Yang, Zhongmin ; Zhang, Yu ; Hamilton, John P. ; Visser, Richard G.F. ; Bachem, Christian W.B. ; Robin Buell, C. ; Zhang, Zhonghua ; Zhang, Chunzhi ; Huang, Sanwen - \ 2020
Nature Genetics 52 (2020)10. - ISSN 1061-4036 - p. 1018 - 1023.
Potato (Solanum tuberosum L.) is the most important tuber crop worldwide. Efforts are underway to transform the crop from a clonally propagated tetraploid into a seed-propagated, inbred-line-based hybrid, but this process requires a better understanding of potato genome. Here, we report the 1.67-Gb haplotype-resolved assembly of a diploid potato, RH89-039-16, using a combination of multiple sequencing strategies, including circular consensus sequencing. Comparison of the two haplotypes revealed ~2.1% intragenomic diversity, including 22,134 predicted deleterious mutations in 10,642 annotated genes. In 20,583 pairs of allelic genes, 16.6% and 30.8% exhibited differential expression and methylation between alleles, respectively. Deleterious mutations and differentially expressed alleles were dispersed throughout both haplotypes, complicating strategies to eradicate deleterious alleles or stack beneficial alleles via meiotic recombination. This study offers a holistic view of the genome organization of a clonally propagated diploid species and provides insights into technological evolution in resolving complex genomes.
Effects of long-term super absorbent polymer and organic manure on soil structure and organic carbon distribution in different soil layers
Yang, Yonghui ; Wu, Jicheng ; Zhao, Shiwei ; Gao, Cuimin ; Pan, Xiaoying ; Tang, Darrell W.S. ; Ploeg, Martine van der - \ 2020
Soil & Tillage Research 206 (2020). - ISSN 0167-1987
Contribution rate of organic carbon - Organic manure - Soil organic carbon - Soil structure - Super absorbent polymer
Super absorbent polymer (SAP) and organic manure (OM) may improve soil structure and change soil organic carbon (SOC) composition and agroecosystem functioning. However, the understanding of the effects of SAP and OM on SOC composition, specifically in deeper soil layers, is still not clear. The objectives of this study were to examine the effects of long-term application of SAP and OM (8 years) on changes in SOC and soil structure down to a soil depth of 100 cm. Therefore, in order to investigate the stability of soil structure and the distribution of organic carbon at different soil depths (0-10 cm, 10-20 cm,…, 90-100 cm) under long-term application of SAP, OM, and a control treatment, soil structure and soil organic carbon content were analyzed in mixed soil samples and undisturbed soil samples. The results indicated that with depth, the proportion of large aggregates (0.5-2.0 mm) decreased gradually, while the proportion of small aggregates (<0.25 mm) increased gradually. Compared with the control, SAP treatment was conducive to the increment of>0.5 mm soil aggregates in the 0-30 cm and 40-60 cm soil layers (P < 0.05) and 0.25-0.5 mm in the 0-50 cm soil layer (P < 0.05), and while the OM treatment had the same effect in the 0-30 cm soil layer (P < 0.05). The total organic carbon content (TOC) and labile organic carbon content (LOC) of bulk soil increased (0-20 cm) initially with depth, and then decreased (20-70 cm) approximately. In the 0-50 cm soil layer, the TOC and LOC under SAP treatment were higher than those under OM treatment. The SAP treatment was more beneficial to the increase of the TOC and LOC of 0.5-2.0 mm and 0.25-0.5 mm aggregates in the 10-40 cm soil layer compared with the control and OM treatment (P < 0.05). The SAP treatment was also more beneficial in increasing the contribution rate of organic carbon (CROC) in> 0.5 mm aggregates in 0-40 cm soil depth, while the OM treatment was more beneficial in increasing the CROC of > 0.5 mm aggregates in 0-30 cm soil depth. The SAP treatment improved the stability of the soil structure in 0-30 cm and 40-60 cm depths, and the OM treatment had the same effect in the 0-30 cm depth. Compared with the control and OM treatments, SAP treatment has shown to be the most beneficial in improving soil structure and increasing organic carbon content.
RPS5 interacts with the rabbit hemorrhagic disease virus 3' extremities region and plays a role in virus replication
Guo, Hongyuan ; Zhu, Jie ; Miao, Qiuhong ; Qi, Ruibin ; Tang, Aoxing ; Liu, Chuncao ; Yang, Hongzao ; Yuan, Ligang ; Liu, Guangqing - \ 2020
Veterinary Microbiology 249 (2020). - ISSN 0378-1135
Rabbit hemorrhagic disease virus - RNA-protein interaction - RPS5 - Viral replication
Rabbit hemorrhagic disease virus (RHDV), a member of Caliciviridae family, causes a highly contagious disease in rabbits. The RHDV replication mechanism is poorly understood due to the lack of a suitable culture system in vitro. This study identified RHDV 5' and 3' extremities (Ex) RNA binding proteins from the rabbit kidney cell line RK-13 based on a pull-down assay by applying a tRNA scaffold streptavidin aptamer. Using mass spectrometry (MS), several host proteins were discovered which interact with RHDV 5' and 3' Ex RNA. The ribosomal protein S5 (RPS5) was shown to interact with RHDV 3' Ex RNA directly by RNA-pulldown and confocal microscopy. To further investigate the role of RPS5 in RHDV replication, small interfering RNAs for RPS5 and RPS5 eukaryotic expression plasmids were used to change the expression level of RPS5 in RK-13 cells and the results showed that the RHDV replication and translation levels were positively correlated with the expression level of RPS5. It was also verified that RPS5 promoted RHDV replication by constructing RPS5 stable overexpression cell lines and RPS5 knockdown cell lines. In summary, it has been identified that RPS5 interacted with the RHDV 3' Ex RNA region and played a role in virus replication. These results will help to understand the mechanism of RHDV replication.
Aggregate-associated changes in nutrient properties, microbial community and functions in a greenhouse vegetable field based on an eight-year fertilization experiment of China
Luan, Hao An ; Gao, Wei ; Tang, Ji Wei ; Li, Ruo Nan ; Li, Ming Yue ; Zhang, Huai Zhi ; Chen, Xinping ; Masiliunas, Dainius ; Huang, Shao Wen - \ 2020
Journal of Integrative Agriculture 19 (2020)10. - ISSN 2095-3119 - p. 2530 - 2548.
fertilization - microbial characteristics - soil aggregate distribution
Soil aggregation, microbial community, and functions (i.e., extracellular enzyme activities; EEAs) are critical factors affecting soil C dynamics and nutrient cycling. We assessed soil aggregate distribution, stability, nutrients, and microbial characteristics within >2, 0.25–2, 0.053–0.25, and <0.053 mm aggregates, based on an eight-year field experiment in a greenhouse vegetable field in China. The field experiment includes four treatments: 100% N fertilizer (CF), 50% substitution of N fertilizer with manure (M), straw (S), and manure plus straw (MS). The amounts of nutrient (N, P2O5, and K2O) input were equal in each treatment. Results showed higher values of mean weight diameter in organic-amended soils (M, MS, and S, 2.43–2.97) vs. CF-amended soils (1.99). Relative to CF treatment, organic amendments had positive effects on nutrient (i.e., available N, P, and soil organic C (SOC)) conditions, microbial (e.g., bacterial and fungal) growth, and EEAs in the >0.053 mm aggregates, but not in the <0.053 mm aggregates. The 0.25–0.053 mm aggregates exhibited better nutrient conditions and hydrolytic activity, while the <0.053 mm aggregates had poor nutrient conditions and higher oxidative activity among aggregates, per SOC, available N, available P, and a series of enzyme activities. These results indicated that the 0.25–0.053 mm (<0.053 mm) aggregates provide suitable microhabitats for hydrolytic (oxidative) activity. Interestingly, we found that hydrolytic and oxidative activities were mainly impacted by fertilization (58.5%, P<0.01) and aggregate fractions (50.5%, P<0.01), respectively. The hydrolytic and oxidative activities were significantly (P<0.01) associated with nutrients (SOC and available N) and pH, electrical conductivity, respectively. Furthermore, SOC, available N, and available P closely (P<0.05) affected microbial communities within >0.25, 0.25–0.053, and <0.053 mm aggregates, respectively. These findings provide several insights into microbial characteristics within aggregates under different fertilization modes in the greenhouse vegetable production system in China.
Highly Stable Perovskite Supercrystals via Oil-in-Oil Templating
Tang, Yingying ; Gomez, Leyre ; Lesage, Arnon ; Marino, Emanuele ; Kodger, Thomas E. ; Meijer, Janne Mieke ; Kolpakov, Paul ; Meng, Jie ; Zheng, Kaibo ; Gregorkiewicz, Tom ; Schall, Peter - \ 2020
Nano Letters 20 (2020)8. - ISSN 1530-6984 - p. 5997 - 6004.
assembly - emulsion-droplet templating - perovskite films - stability - supercrystals
Inorganic perovskites display an enticing foreground for their wide range of optoelectronic applications. Recently, supercrystals (SCs) of inorganic perovskite nanocrystals (NCs) have been reported to possess highly ordered structure as well as novel collective optical properties, opening new opportunities for efficient films. Here, we report the large-scale assembly control of spherical, cubic, and hexagonal SCs of inorganic perovskite NCs through templating by oil-in-oil emulsions. We show that an interplay between the roundness of the cubic NCs and the tension of the confining droplet surface sets the superstructure morphology, and we exploit this interplay to design dense hyperlattices of SCs. The SC films show strongly enhanced stability for at least two months without obvious structural degradation and minor optical changes. Our results on the controlled large-scale assembly of perovskite NC superstructures provide new prospects for the bottom-up production of optoelectronic devices based on the microfluidic production of mesoscopic building blocks.
Wheat-derived arabinoxylans reduced M2-macrophage functional activity, but enhanced monocyte-recruitment capacity
Govers, Coen ; Tang, Yongfu ; Stolte, Ellen H. ; Wichers, Harry J. ; Mes, Jurriaan J. - \ 2020
Food & Function 11 (2020)8. - ISSN 2042-6496 - p. 7073 - 7083.
The immunomodulatory properties of non-digestible polysaccharides (NDPs) have been recognized in in vitro and in vivo studies. The latter mostly demonstrated altered frequencies and inflammatory status of immune cells as clinical parameters. Most of the NDP activity will be exerted in the intestine where they can directly interact with macrophages. The predominant macrophage phenotype in the intestine is M2-like, with M1-like macrophages arising during inflammation. Here, we investigated transcriptional and functional impact on these macrophage phenotypes by NDP-treatment (i.e. yeast-derived soluble β-glucan (yeast-βG), apple-derived RG-I (apple-RGI), shiitake-derived β-glucan (shiitake-βG) or wheat-derived arabinoxylan (wheat-AX)). Wheat-AX, and to a lesser extent shiitake-βG and apple-RGI but not yeast-βG, reduced endocytosis and antigen processing capacity of M1- and M2-like macrophages. Moreover, the NDPs, and most notably wheat-AX, strongly induced transcription and secretion of a unique set of cytokines and chemokines. Conditioned medium from wheat-AX-treated M2-like macrophages subsequently demonstrated strongly increased monocyte recruitment capacity. These findings are in line with clinically observed immunomodulatory aspects of NDPs making it tempting to speculate that clinical activity of some NDPs is mediated through enhanced chemoattraction and modifying activity of intestinal immune cells.
Pantothenic acid requirement of male White Pekin ducks from hatch to 21 days of age
Tang, J. ; Zhang, B. ; Xue, M. ; Shi, W.B. ; Wu, Y.B. ; Feng, Y.L. ; Huang, W. ; Zhou, Z.K. ; Xie, M. ; Hou, S.S. - \ 2020
Animal Feed Science and Technology 269 (2020). - ISSN 0377-8401
Duck - Growth performance - Pantothenic acid - Requirement
An experiment was conducted to determine the effects of dietary pantothenic acid levels on growth performance, carcass traits, and pantothenic acid status of male White Pekin ducks from hatch to 21 days of age, and to evaluate the requirement of this B-vitamin for starter ducks. Different levels pantothenic acid (0, 2, 4, 6, 8, 10, and 20 mg/kg) were supplemented to corn-soy isolate protein basal diet to produce 7 dietary treatments with different analyzed total pantothenic acid levels (4.65, 6.80, 8.39, 9.98, 12.04, 13.70, and 22.50 mg/kg). A total of 448 one-day-old male White Pekin ducks were allotted to 7 dietary treatments with 8 replicate pens of 8 birds per pen. At 21 days of age, body weight, average daily weight gain (ADG), average daily feed intake (ADFI), gain to feed ratio (G/F), liver pantothenic acid content, as well as percentage yield of breast meat, leg meat, and abdominal fat were examined. The growth depression, exudate on eyelids, dermatosis, poor feathering, and 100 % of mortality were observed in the ducks fed the basal diet without pantothenic acid supplementation, and these adverse effects were ameliorated by pantothenic acid supplementation. The starter ducks on the diet containing 6.80 mg/kg of pantothenic acid had a lower parameter profile of body weight, ADG, ADFI, G/F, breast meat yield, abdominal fat yield, and liver pantothenic acid content compared to the birds fed the diets with higher levels of pantothenic acid (P < 0.05). And these criteria showed a linear or quadratic response to increasing dietary pantothenic acid levels (P < 0.05). The pantothenic acid requirements (based on dietary total pantothenic acid) of starter male White Pekin ducks for body weight, ADG, ADFI, G/F, and liver pantothenic acid content were 8.95, 8.95, 8.59, 9.56, and 10.22 mg/kg based on broken-line regression, while were 10.04, 10.05, 9.18, 11.01, and 11.24 mg/kg based on quadratic broken-line regression, respectively.
The FLUXNET2015 dataset and the ONEFlux processing pipeline for eddy covariance data
Pastorello, Gilberto ; Trotta, Carlo ; Canfora, Eleonora ; Chu, Housen ; Christianson, Danielle ; Cheah, You Wei ; Poindexter, Cristina ; Chen, Jiquan ; Elbashandy, Abdelrahman ; Humphrey, Marty ; Isaac, Peter ; Polidori, Diego ; Ribeca, Alessio ; Ingen, Catharine van; Zhang, Leiming ; Amiro, Brian ; Ammann, Christof ; Arain, M.A. ; Ardö, Jonas ; Arkebauer, Timothy ; Arndt, Stefan K. ; Arriga, Nicola ; Aubinet, Marc ; Aurela, Mika ; Baldocchi, Dennis ; Barr, Alan ; Beamesderfer, Eric ; Marchesini, Luca Belelli ; Bergeron, Onil ; Beringer, Jason ; Bernhofer, Christian ; Berveiller, Daniel ; Billesbach, Dave ; Black, Thomas Andrew ; Blanken, Peter D. ; Bohrer, Gil ; Boike, Julia ; Bolstad, Paul V. ; Bonal, Damien ; Bonnefond, Jean Marc ; Bowling, David R. ; Bracho, Rosvel ; Brodeur, Jason ; Brümmer, Christian ; Buchmann, Nina ; Burban, Benoit ; Burns, Sean P. ; Buysse, Pauline ; Cale, Peter ; Cavagna, Mauro ; Cellier, Pierre ; Chen, Shiping ; Chini, Isaac ; Christensen, Torben R. ; Cleverly, James ; Collalti, Alessio ; Consalvo, Claudia ; Cook, Bruce D. ; Cook, David ; Coursolle, Carole ; Cremonese, Edoardo ; Curtis, Peter S. ; Andrea, Ettore D'; Rocha, Humberto da; Dai, Xiaoqin ; Davis, Kenneth J. ; Cinti, Bruno De; Grandcourt, Agnes de; Ligne, Anne De; Oliveira, Raimundo C. De; Delpierre, Nicolas ; Desai, Ankur R. ; Bella, Carlos Marcelo Di; Tommasi, Paul di; Dolman, Han ; Domingo, Francisco ; Dong, Gang ; Dore, Sabina ; Duce, Pierpaolo ; Dufrêne, Eric ; Dunn, Allison ; Dušek, Jiří ; Eamus, Derek ; Eichelmann, Uwe ; ElKhidir, Hatim Abdalla M. ; Eugster, Werner ; Ewenz, Cacilia M. ; Ewers, Brent ; Famulari, Daniela ; Fares, Silvano ; Feigenwinter, Iris ; Feitz, Andrew ; Fensholt, Rasmus ; Filippa, Gianluca ; Fischer, Marc ; Frank, John ; Galvagno, Marta ; Gharun, Mana ; Gianelle, Damiano ; Gielen, Bert ; Gioli, Beniamino ; Gitelson, Anatoly ; Goded, Ignacio ; Goeckede, Mathias ; Goldstein, Allen H. ; Gough, Christopher M. ; Goulden, Michael L. ; Graf, Alexander ; Griebel, Anne ; Gruening, Carsten ; Grünwald, Thomas ; Hammerle, Albin ; Han, Shijie ; Han, Xingguo ; Hansen, Birger Ulf ; Hanson, Chad ; Hatakka, Juha ; He, Yongtao ; Hehn, Markus ; Heinesch, Bernard ; Hinko-Najera, Nina ; Hörtnagl, Lukas ; Hutley, Lindsay ; Ibrom, Andreas ; Ikawa, Hiroki ; Jackowicz-Korczynski, Marcin ; Janouš, Dalibor ; Jans, Wilma ; Jassal, Rachhpal ; Jiang, Shicheng ; Kato, Tomomichi ; Khomik, Myroslava ; Klatt, Janina ; Knohl, Alexander ; Knox, Sara ; Kobayashi, Hideki ; Koerber, Georgia ; Kolle, Olaf ; Kosugi, Yoshiko ; Kotani, Ayumi ; Kowalski, Andrew ; Kruijt, Bart ; Kurbatova, Julia ; Kutsch, Werner L. ; Kwon, Hyojung ; Launiainen, Samuli ; Laurila, Tuomas ; Law, Bev ; Leuning, Ray ; Li, Yingnian ; Liddell, Michael ; Limousin, Jean Marc ; Lion, Marryanna ; Liska, Adam J. ; Lohila, Annalea ; López-Ballesteros, Ana ; López-Blanco, Efrén ; Loubet, Benjamin ; Loustau, Denis ; Lucas-Moffat, Antje ; Lüers, Johannes ; Ma, Siyan ; Macfarlane, Craig ; Magliulo, Vincenzo ; Maier, Regine ; Mammarella, Ivan ; Manca, Giovanni ; Marcolla, Barbara ; Margolis, Hank A. ; Marras, Serena ; Massman, William ; Mastepanov, Mikhail ; Matamala, Roser ; Matthes, Jaclyn Hatala ; Mazzenga, Francesco ; McCaughey, Harry ; McHugh, Ian ; McMillan, Andrew M.S. ; Merbold, Lutz ; Meyer, Wayne ; Meyers, Tilden ; Miller, Scott D. ; Minerbi, Stefano ; Moderow, Uta ; Monson, Russell K. ; Montagnani, Leonardo ; Moore, Caitlin E. ; Moors, Eddy ; Moreaux, Virginie ; Moureaux, Christine ; Munger, J.W. ; Nakai, Taro ; Neirynck, Johan ; Nesic, Zoran ; Nicolini, Giacomo ; Noormets, Asko ; Northwood, Matthew ; Nosetto, Marcelo ; Nouvellon, Yann ; Novick, Kimberly ; Oechel, Walter ; Olesen, Jørgen Eivind ; Ourcival, Jean Marc ; Papuga, Shirley A. ; Parmentier, Frans Jan ; Paul-Limoges, Eugenie ; Pavelka, Marian ; Peichl, Matthias ; Pendall, Elise ; Phillips, Richard P. ; Pilegaard, Kim ; Pirk, Norbert ; Posse, Gabriela ; Powell, Thomas ; Prasse, Heiko ; Prober, Suzanne M. ; Rambal, Serge ; Rannik, Üllar ; Raz-Yaseef, Naama ; Reed, David ; Dios, Victor Resco de; Restrepo-Coupe, Natalia ; Reverter, Borja R. ; Roland, Marilyn ; Sabbatini, Simone ; Sachs, Torsten ; Saleska, Scott R. ; Sánchez-Cañete, Enrique P. ; Sanchez-Mejia, Zulia M. ; Schmid, Hans Peter ; Schmidt, Marius ; Schneider, Karl ; Schrader, Frederik ; Schroder, Ivan ; Scott, Russell L. ; Sedlák, Pavel ; Serrano-Ortíz, Penélope ; Shao, Changliang ; Shi, Peili ; Shironya, Ivan ; Siebicke, Lukas ; Šigut, Ladislav ; Silberstein, Richard ; Sirca, Costantino ; Spano, Donatella ; Steinbrecher, Rainer ; Stevens, Robert M. ; Sturtevant, Cove ; Suyker, Andy ; Tagesson, Torbern ; Takanashi, Satoru ; Tang, Yanhong ; Tapper, Nigel ; Thom, Jonathan ; Tiedemann, Frank ; Tomassucci, Michele ; Tuovinen, Juha Pekka ; Urbanski, Shawn ; Valentini, Riccardo ; Molen, Michiel van der; Gorsel, Eva van; Huissteden, Ko van; Varlagin, Andrej ; Verfaillie, Joseph ; Vesala, Timo ; Vincke, Caroline ; Vitale, Domenico ; Vygodskaya, Natalia ; Walker, Jeffrey P. ; Walter-Shea, Elizabeth ; Wang, Huimin ; Weber, Robin ; Westermann, Sebastian ; Wille, Christian ; Wofsy, Steven ; Wohlfahrt, Georg ; Wolf, Sebastian ; Woodgate, William ; Li, Yuelin ; Zampedri, Roberto ; Zhang, Junhui ; Zhou, Guoyi ; Zona, Donatella ; Agarwal, Deb ; Biraud, Sebastien ; Torn, Margaret ; Papale, Dario - \ 2020
Scientific Data 7 (2020)1. - ISSN 2052-4463 - 1 p.
The FLUXNET2015 dataset provides ecosystem-scale data on CO2, water, and energy exchange between the biosphere and the atmosphere, and other meteorological and biological measurements, from 212 sites around the globe (over 1500 site-years, up to and including year 2014). These sites, independently managed and operated, voluntarily contributed their data to create global datasets. Data were quality controlled and processed using uniform methods, to improve consistency and intercomparability across sites. The dataset is already being used in a number of applications, including ecophysiology studies, remote sensing studies, and development of ecosystem and Earth system models. FLUXNET2015 includes derived-data products, such as gap-filled time series, ecosystem respiration and photosynthetic uptake estimates, estimation of uncertainties, and metadata about the measurements, presented for the first time in this paper. In addition, 206 of these sites are for the first time distributed under a Creative Commons (CC-BY 4.0) license. This paper details this enhanced dataset and the processing methods, now made available as open-source codes, making the dataset more accessible, transparent, and reproducible.
The global abundance of tree palms
Muscarella, Robert ; Emilio, Thaise ; Phillips, Oliver L. ; Lewis, Simon L. ; Slik, Ferry ; Baker, William J. ; Couvreur, Thomas L.P. ; Eiserhardt, Wolf L. ; Svenning, Jens Christian ; Affum-Baffoe, Kofi ; Aiba, Shin Ichiro ; Almeida, Everton C. de; Almeida, Samuel S. de; Oliveira, Edmar Almeida de; Álvarez-Dávila, Esteban ; Alves, Luciana F. ; Alvez-Valles, Carlos Mariano ; Carvalho, Fabrício Alvim ; Guarin, Fernando Alzate ; Andrade, Ana ; Aragão, Luis E.O.C. ; Murakami, Alejandro Araujo ; Arroyo, Luzmila ; Ashton, Peter S. ; Corredor, Gerardo A.A. ; Baker, Timothy R. ; Camargo, Plinio Barbosa de; Barlow, Jos ; Bastin, Jean François ; Bengone, Natacha Nssi ; Berenguer, Erika ; Berry, Nicholas ; Blanc, Lilian ; Böhning-Gaese, Katrin ; Bonal, Damien ; Bongers, Frans ; Bradford, Matt ; Brambach, Fabian ; Brearley, Francis Q. ; Brewer, Steven W. ; Camargo, Jose L.C. ; Campbell, David G. ; Castilho, Carolina V. ; Castro, Wendeson ; Catchpole, Damien ; Cerón Martínez, Carlos E. ; Chen, Shengbin ; Chhang, Phourin ; Cho, Percival ; Chutipong, Wanlop ; Clark, Connie ; Collins, Murray ; Comiskey, James A. ; Medina, Massiel Nataly Corrales ; Costa, Flávia R.C. ; Culmsee, Heike ; David-Higuita, Heriberto ; Davidar, Priya ; Aguila-Pasquel, Jhon del; Derroire, Géraldine ; Fiore, Anthony Di; Do, Tran Van; Doucet, Jean Louis ; Dourdain, Aurélie ; Drake, Donald R. ; Ensslin, Andreas ; Erwin, Terry ; Ewango, Corneille E.N. ; Ewers, Robert M. ; Fauset, Sophie ; Feldpausch, Ted R. ; Ferreira, Joice ; Ferreira, Leandro Valle ; Fischer, Markus ; Franklin, Janet ; Fredriksson, Gabriella M. ; Gillespie, Thomas W. ; Gilpin, Martin ; Gonmadje, Christelle ; Gunatilleke, Arachchige Upali Nimal ; Hakeem, Khalid Rehman ; Hall, Jefferson S. ; Hamer, Keith C. ; Harris, David J. ; Harrison, Rhett D. ; Hector, Andrew ; Hemp, Andreas ; Herault, Bruno ; Pizango, Carlos Gabriel Hidalgo ; Honorio Coronado, Eurídice N. ; Hubau, Wannes ; Hussain, Mohammad Shah ; Ibrahim, Faridah Hanum ; Imai, Nobuo ; Joly, Carlos A. ; Joseph, Shijo ; Anitha, K. ; Kartawinata, Kuswata ; Kassi, Justin ; Killeen, Timothy J. ; Kitayama, Kanehiro ; Klitgård, Bente Bang ; Kooyman, Robert ; Labrière, Nicolas ; Larney, Eileen ; Laumonier, Yves ; Laurance, Susan G. ; Laurance, William F. ; Lawes, Michael J. ; Levesley, Aurora ; Lisingo, Janvier ; Lovejoy, Thomas ; Lovett, Jon C. ; Lu, Xinghui ; Lykke, Anne Mette ; Magnusson, William E. ; Mahayani, Ni Putu Diana ; Malhi, Yadvinder ; Mansor, Asyraf ; Peña, Jose Luis Marcelo ; Marimon-Junior, Ben H. ; Marshall, Andrew R. ; Melgaco, Karina ; Bautista, Casimiro Mendoza ; Mihindou, Vianet ; Millet, Jérôme ; Milliken, William ; Mohandass, D. ; Mendoza, Abel Lorenzo Monteagudo ; Mugerwa, Badru ; Nagamasu, Hidetoshi ; Nagy, Laszlo ; Seuaturien, Naret ; Nascimento, Marcelo T. ; Neill, David A. ; Neto, Luiz Menini ; Nilus, Rueben ; Vargas, Mario Percy Núñez ; Nurtjahya, Eddy ; Araújo, R.N.O. de; Onrizal, Onrizal ; Palacios, Walter A. ; Palacios-Ramos, Sonia ; Parren, Marc ; Paudel, Ekananda ; Morandi, Paulo S. ; Pennington, R.T. ; Pickavance, Georgia ; Pipoly, John J. ; Pitman, Nigel C.A. ; Poedjirahajoe, Erny ; Poorter, Lourens ; Poulsen, John R. ; Prasad, P.R.C. ; Prieto, Adriana ; Puyravaud, Jean Philippe ; Qie, Lan ; Quesada, Carlos A. ; Ramírez-Angulo, Hirma ; Razafimahaimodison, Jean Claude ; Reitsma, Jan Meindert ; Requena-Rojas, Edilson J. ; Correa, Zorayda Restrepo ; Rodriguez, Carlos Reynel ; Roopsind, Anand ; Rovero, Francesco ; Rozak, Andes ; Lleras, Agustín Rudas ; Rutishauser, Ervan ; Rutten, Gemma ; Punchi-Manage, Ruwan ; Salomão, Rafael P. ; Sam, Hoang Van; Sarker, Swapan Kumar ; Satdichanh, Manichanh ; Schietti, Juliana ; Schmitt, Christine B. ; Marimon, Beatriz Schwantes ; Senbeta, Feyera ; Nath Sharma, Lila ; Sheil, Douglas ; Sierra, Rodrigo ; Silva-Espejo, Javier E. ; Silveira, Marcos ; Sonké, Bonaventure ; Steininger, Marc K. ; Steinmetz, Robert ; Stévart, Tariq ; Sukumar, Raman ; Sultana, Aisha ; Sunderland, Terry C.H. ; Suresh, Hebbalalu Satyanarayana ; Tang, Jianwei ; Tanner, Edmund ; Steege, Hans ter; Terborgh, John W. ; Theilade, Ida ; Timberlake, Jonathan ; Torres-Lezama, Armando ; Umunay, Peter ; Uriarte, María ; Gamarra, Luis Valenzuela ; Bult, Martin van de; Hout, Peter van der; Martinez, Rodolfo Vasquez ; Vieira, Ima Célia Guimarães ; Vieira, Simone A. ; Vilanova, Emilio ; Cayo, Jeanneth Villalobos ; Wang, Ophelia ; Webb, Campbell O. ; Webb, Edward L. ; White, Lee ; Whitfeld, Timothy J.S. ; Wich, Serge ; Willcock, Simon ; Wiser, Susan K. ; Young, Kenneth R. ; Zakaria, Rahmad ; Zang, Runguo ; Zartman, Charles E. ; Zo-Bi, Irié Casimir ; Balslev, Henrik - \ 2020
Global Ecology and Biogeography 29 (2020)9. - ISSN 1466-822X - p. 1495 - 1514.
above-ground biomass - abundance patterns - Arecaceae - local abiotic conditions - Neotropics - pantropical biogeography - tropical rainforest - wood density
Aim: Palms are an iconic, diverse and often abundant component of tropical ecosystems that provide many ecosystem services. Being monocots, tree palms are evolutionarily, morphologically and physiologically distinct from other trees, and these differences have important consequences for ecosystem services (e.g., carbon sequestration and storage) and in terms of responses to climate change. We quantified global patterns of tree palm relative abundance to help improve understanding of tropical forests and reduce uncertainty about these ecosystems under climate change. Location: Tropical and subtropical moist forests. Time period: Current. Major taxa studied: Palms (Arecaceae). Methods: We assembled a pantropical dataset of 2,548 forest plots (covering 1,191 ha) and quantified tree palm (i.e., ≥10 cm diameter at breast height) abundance relative to co-occurring non-palm trees. We compared the relative abundance of tree palms across biogeographical realms and tested for associations with palaeoclimate stability, current climate, edaphic conditions and metrics of forest structure. Results: On average, the relative abundance of tree palms was more than five times larger between Neotropical locations and other biogeographical realms. Tree palms were absent in most locations outside the Neotropics but present in >80% of Neotropical locations. The relative abundance of tree palms was more strongly associated with local conditions (e.g., higher mean annual precipitation, lower soil fertility, shallower water table and lower plot mean wood density) than metrics of long-term climate stability. Life-form diversity also influenced the patterns; palm assemblages outside the Neotropics comprise many non-tree (e.g., climbing) palms. Finally, we show that tree palms can influence estimates of above-ground biomass, but the magnitude and direction of the effect require additional work. Conclusions: Tree palms are not only quintessentially tropical, but they are also overwhelmingly Neotropical. Future work to understand the contributions of tree palms to biomass estimates and carbon cycling will be particularly crucial in Neotropical forests.
The mechanism and application of bidirectional extracellular electron transport in the field of energy and environment
Xie, Qingqing ; Lu, Yue ; Tang, Lin ; Zeng, Guangming ; Yang, Zhaohui ; Fan, Changzheng ; Wang, Jingjing ; Atashgahi, Siavash - \ 2020
Critical Reviews in Environmental Science and Technology (2020). - ISSN 1064-3389
Bioremediation - energy production - extracellular electron transfer
Bidirectional extracellular electron transfer (EET) is mediated by back and forth electron delivery between microorganisms and extracellular substances. This enables the exchange of biochemical information and energy with the surrounding environments. As a novel bioenergy strategy, bidirectional EET provides low-cost opportunities for the production of clean energy sources and carriers (e.g., hydrogen and methane) as well as the production of value-added chemicals from carbon dioxide. Electrochemically active bacteria (EAB) can also transform pollutants to less toxic or benign substances in contaminated environments, and therefore they have been widely applied in bioremediation studies. Among all the available EAB, Geobacter and Shewanella are well-known for their versatility to accept/donate electrons from/to external environments. In this review, we focus on how these model EAB generate or harvest energy through bidirectional EET, as well as recent advances in the application of EET in bioelectrochemical technology and environmental bioremediation. Finally, the challenges, perspectives and new directions in the bidirectional EET studies are discussed. (Figure presented.).
Neighbourhood-dependent root distributions and the consequences on root separation in arid ecosystems
Chen, Bin J.W. ; Xu, Chi ; Liu, Mao Song ; Huang, Zheng Y.X. ; Zhang, Ming Juan ; Tang, Jian ; Anten, Niels P.R. - \ 2020
Journal of Ecology 108 (2020)4. - ISSN 0022-0477 - p. 1635 - 1648.
dryland - growth form - niche partitioning - plant–plant interactions - root competition - root distribution - root separation - species coexistence
Interspecific root separation is an important example of spatial niche differentiation that drives species coexistence in many ecosystems. Particularly under water-stressed conditions, it is believed to be an inevitable outcome of species interactions. However, evidence for and against this idea has been found. So far, studies aiming at reconciling the debate have mainly focused on abiotic determinants. It remains unclear if and to what extent root separation depends on the type and growth form of interacting plants. We conducted a detailed field study in three adjacently located (with pairwise distances <500 m) arid patchy communities where a common tussock grass species Achnatherum splendens grew in association with either a tree Elaeagnus angustifolia, a shrub Nitraria tangutorum or a perennial forb species Sophora alopecuroides. In each community, roots and soils were sampled along the soil layers from five depths (0–10, 10–30, 30–60, 60–100 and 100–150 cm) in the patches and in the adjacent bare ground outside the patches. Significant vertical interspecific root separation occurred in the species-association patches of tree-grass and forb-grass communities, but not in the shrub-grass community. As the neighbour changed going from trees to shrubs and to forbs, rooting profiles of the grass Achnatherum became progressively deeper, with progressively less roots allocated in the upmost 10 cm soil layer and more in the subsequent two layers. After controlling for the differences in soil water and nutrient conditions among the three communities, the effects of neighbour type on grass rooting profiles remained robust. Synthesis. We found that the root distributions of plants in the dryland strongly depend on the type of neighbour plants, which can, at least partially, determine the extent of interspecific root separation at the community scale. Our work poses new questions about plasticity in root distribution and helps to better understand species interactions and coexistence under stressful conditions.
Sel1L-Hrd1 ER-associated degradation maintains β cell identity via TGF-β signaling
Shrestha, Neha ; Liu, Tongyu ; Ji, Yewei ; Reinert, Rachel B. ; Torres, Mauricio ; Li, Xin ; Zhang, Maria ; Tang, Chih-Hang Anthony ; Hu, Chih-Chi Andrew ; Liu, Chengyang ; Naji, Ali ; Liu, Ming ; Lin, Jiandie D. ; Kersten, Sander ; Arvan, Peter ; Qi, Ling - \ 2020
The Journal of Clinical Investigation 130 (2020)7. - ISSN 0021-9738 - p. 3499 - 3510.
β Cell apoptosis and dedifferentiation are 2 hotly debated mechanisms underlying β cell loss in type 2 diabetes; however, the molecular drivers underlying such events remain largely unclear. Here, we performed a side-by-side comparison of mice carrying β cell-specific deletion of ER-associated degradation (ERAD) and autophagy. We reported that, while autophagy was necessary for β cell survival, the highly conserved Sel1L-Hrd1 ERAD protein complex was required for the maintenance of β cell maturation and identity. Using single-cell RNA-Seq, we demonstrated that Sel1L deficiency was not associated with β cell loss, but rather loss of β cell identity. Sel1L-Hrd1 ERAD controlled β cell identity via TGF-β signaling, in part by mediating the degradation of TGF-β receptor 1. Inhibition of TGF-β signaling in Sel1L-deficient β cells augmented the expression of β cell maturation markers and increased the total insulin content. Our data revealed distinct pathogenic effects of 2 major proteolytic pathways in β cells, providing a framework for therapies targeting distinct mechanisms of protein quality control
ER-associated degradation is required for the maintenance of β cell identity via TGFβ signaling
Shrestha, Neha ; Liu, T. ; Ji, Yewei ; Reinert, Rachel B. ; Torres, Mauricio ; Zhang, M. ; Tang, C.A. ; Hu, C.A. ; Liu, Chengyang ; Naji, Ali ; Lin, Jiandie D. ; Kersten, Sander ; Arvan, Peter ; Qi, Ling ; Hooiveld, Guido - \ 2020
Wageningen University & Research
Mus musculus - GSE143757 - PRJNA601502
β cell apoptosis and dedifferentiation are two hotly-debated mechanisms underlying β cell loss in type 2 diabetes (T2D); however, the molecular drivers underlying such events remain largely unclear. Here, by performing a side-by-side comparison of mice carrying β cell-specific deletion of endoplasmic reticulum (ER)-associated degradation (ERAD) and autophagy, we report that while autophagy appears necessary for β cell survival, the highly conserved Sel1L-Hrd1 ERAD protein complex is required for the maintenance of β cell maturation and identity. Notably, SEL1L expression is significantly reduced in human T2D islets compared to healthy human islets. At the single cell level, we demonstrate that Sel1L deficiency is not associated with β cell loss, but rather loss of β cell identity. Mechanistically, we find that Sel1L-Hrd1 ERAD controls β cell identity via TGFβ signaling, in part by mediating the degradation of TGF-β receptor 1 (TGFβRI). Inhibition of TGFβ signaling in Sel1L-deficient β cells augments the expression of β cell maturation markers and increases the total insulin content. Our data reveal profound but distinct pathogenic effects of two major proteolytic pathways in β cells, providing a new framework for therapies targeting distinct mechanisms of protein quality control
Replication Data for: The stove, dome, and umbrella effects of pollutant aerosol on the planetary boundary layer: a large-eddy simulation and observations in Beijing
Ma, Yongjing ; Ye, Jianhuai ; Xin, Jinyuan ; Zhang, Wenyu ; Vila-Guerau de Arellano, Jordi ; Zhao, Dandan ; Dai, Lindong ; Ma, Yongxiang ; Wu, Xiaoyan ; Xia, Xiangao ; Tang, Guiqian ; Shen, Pengke ; Lei, Yali ; Martin, Scot T. - \ 2020
Dataset for campaign observations and LES input file for the reference case.
The Stove, Dome, and Umbrella Effects of Atmospheric Aerosol on the Development of the Planetary Boundary Layer in Hazy Regions
Ma, Yongjing ; Ye, Jianhuai ; Xin, Jinyuan ; Zhang, Wenyu ; Vilà‐Guerau de Arellano, Jordi ; Wang, Shigong ; Zhao, Dandan ; Dai, Lindong ; Ma, Yongxiang ; Wu, Xiaoyan ; Xia, Xiangao ; Tang, Guiqian ; Wang, Yuesi ; Shen, Pengke ; Lei, Yali ; Martin, Scot T. - \ 2020
Geophysical Research Letters 47 (2020)13. - ISSN 0094-8276
Atmospheric aerosol plays critical roles in suppressing planetary boundary layer (PBL) and deteriorating air quality. However, comprehensive understanding on how aerosol optical properties (absorption and scattering) affect PBL remains lacking. Utilizing a large‐eddy simulation model incorporated with in situ observations, we demonstrate distinct impacts of absorption aerosol on PBL development when it is present below (stove effect and promotion) or above morning residual layer (dome effect and strong inhibition) and similar inhibition umbrella effects of scattering aerosol on PBL regardless of its vertical locations. There exists a transition height, above which absorption aerosol is more effective in suppressing PBL and below which scattering aerosol dominates the suppression. This height is highly related to the height of morning residual layer. Aerosol stove, dome, and umbrella effects enrich our knowledge on aerosol‐PBL interactions and the latter two can be interpreted as “double inhibitions” in promoting haze episodes in the North China Plain.
Computer-assisted terrain sketch mapping that considers the geomorphological features in a loess landform
Cheng, Yihan ; Yang, Xin ; Liu, Hailong ; Li, Min ; Rossiter, David G. ; Xiong, Liyang ; Tang, Guoan - \ 2020
Geomorphology 364 (2020). - ISSN 0169-555X
DEM - Loess landform - Terrain sketch map - Visual hierarchy division - Visual outline generalisation
In geography, a terrain sketch map is necessary to understand the features and internal structures of a landscape due to its ability to depict key information in a geographical scene using as few lines as possible. Previous computer-drawn sketch maps have focused on the artistic effect rather than on depicting terrain features and landform structures, and thus, they differ considerably from hand-drawn sketch maps by geographers or geologists. This study develops a DEM-based method for terrain sketch mapping that considers the typical feature descriptions of a loess landform and the visual hierarchy expression in line with the law of visual perspective. The method was tested with experiments on two landforms of Chinese Loess Plateau, based on digital elevation models (DEM) with a horizontal resolution of 5 m. In the developed method, first, typical terrain features, including the visual outline, shoulder line, gully and flow lines, are extracted from the DEM. Second, the map is divided into three visual levels in accordance with the data extension and viewing point. Then, terrain feature lines are assigned to different visual levels. Finally, the visual outlines in the distant view are generalized following the law of visual perspective. Results are assessed through a questionnaire with specialists (experts) and students (non-experts). The sketch map was able to characterise loess landforms, and is somewhat similar to traditional hand-drawn maps. The generalisation method realises the near and distant view characteristics of a sketch map, which are detailed and simplified, respectively. The results of the questionnaire also showed that our method presents terrain morphology and geographical scene more accurately and reliably than a hand-drawn sketch map.
Towards a multiscale crop modelling framework for climate change adaptation assessment
Peng, Bin ; Guan, Kaiyu ; Tang, Jinyun ; Ainsworth, Elizabeth A. ; Asseng, Senthold ; Bernacchi, Carl J. ; Cooper, Mark ; Delucia, Evan H. ; Elliott, Joshua W. ; Ewert, Frank ; Grant, Robert F. ; Gustafson, David I. ; Hammer, Graeme L. ; Jin, Zhenong ; Jones, James W. ; Kimm, Hyungsuk ; Lawrence, David M. ; Li, Yan ; Lombardozzi, Danica L. ; Marshall-Colon, Amy ; Messina, Carlos D. ; Ort, Donald R. ; Schnable, James C. ; Vallejos, C.E. ; Wu, Alex ; Yin, Xinyou ; Zhou, Wang - \ 2020
Nature Plants 6 (2020)4. - ISSN 2055-026X - p. 338 - 348.
Predicting the consequences of manipulating genotype (G) and agronomic management (M) on agricultural ecosystem performances under future environmental (E) conditions remains a challenge. Crop modelling has the potential to enable society to assess the efficacy of G × M technologies to mitigate and adapt crop production systems to climate change. Despite recent achievements, dedicated research to develop and improve modelling capabilities from gene to global scales is needed to provide guidance on designing G × M adaptation strategies with full consideration of their impacts on both crop productivity and ecosystem sustainability under varying climatic conditions. Opportunities to advance the multiscale crop modelling framework include representing crop genetic traits, interfacing crop models with large-scale models, improving the representation of physiological responses to climate change and management practices, closing data gaps and harnessing multisource data to improve model predictability and enable identification of emergent relationships. A fundamental challenge in multiscale prediction is the balance between process details required to assess the intervention and predictability of the system at the scales feasible to measure the impact. An advanced multiscale crop modelling framework will enable a gene-to-farm design of resilient and sustainable crop production systems under a changing climate at regional-to-global scales.
Effects of nitrogen addition on soil methane uptake in global forest biomes
Xia, Nan ; Du, Enzai ; Wu, Xinhui ; Tang, Yang ; Wang, Yang ; Vries, Wim de - \ 2020
Environmental Pollution 264 (2020). - ISSN 0269-7491
Forest - Nitrogen addition - Nitrogen deposition - Soil methane uptake
Nitrogen (N) deposition has been conventionally thought to decrease forest soil methane (CH4) uptake, while the biome specific and dose dependent effect is poorly understood. Based on a meta-analysis of 63 N addition trials from 7 boreal forests, 8 temperate forests, 13 subtropical and 4 tropical forests, we evaluated the effects of N addition on soil CH4 uptake fluxes across global forest biomes. When combining all N addition levels, soil CH4 uptake was insignificantly decreased by 7% in boreal forests, while N addition significantly decreased soil CH4 uptake by 39% in temperate forests and by 21% in subtropical and tropical forests, respectively. Meta-regression analyses, however, indicated a shift from a positive to a negative effect on soil CH4 uptake with increasing N additions both in boreal forests (threshold = 48 kg N ha−1 yr−1) and temperate forests (threshold = 27 kg N ha−1 yr−1), while no such shift was found in subtropical and tropical forests. Considering that current N deposition to most boreal and temperate forests is below the abovementioned thresholds, N deposition likely exerts a positive to neutral effect on soil CH4 uptake in both forest biomes. Our results provide new insights on the biome specific and dose dependent effect of N addition on soil CH4 sink in global forests and suggest that the current understanding that N deposition decreases forest soil CH4 uptake is flawed by high levels of experimental N addition.
Organic amendment increases soil respiration in a greenhouse vegetable production system through decreasing soil organic carbon recalcitrance and increasing carbon-degrading microbial activity
Luan, Haoan ; Gao, Wei ; Huang, Shaowen ; Tang, Jiwei ; Li, Mingyue ; Zhang, Huaizhi ; Chen, Xinping ; Masiliūnas, Dainius - \ 2020
Journal of Soils and Sediments 20 (2020). - ISSN 1439-0108 - p. 2877 - 2892.
Purpose: Recent works have shown that fertilization has an important influence on soil respiration (Rs); however, the underlying mechanisms involved in regulating Rs in greenhouse vegetable production (GVP) systems remain unclear.
Materials and methods: Samples from six kinds of soils that were amended with different fertilization patterns (8 years) were incubated for 36 days to determine soil microbial community (PLFA), enzyme activities, soil organic C (SOC) quality (13C NMR), and Rs in a GVP system in Tianjin, China. Treatments included 100% chemical N (CN) and different substitution rates of CN with manure-N and/or straw-N.
Results and discussion: Compared with 100%CN treatment, organic amendment strongly promoted microbial (e.g., fungi, bacteria, and actinomycetes) growth, enhanced the majority of C-degrading enzyme activities, affected SOC chemical composition with increasing O-alkyl (labile) C and reducing aromatic (stable) C, decreased SOC recalcitrance, and enhanced Rs. Redundancy analysis indicated that variations in microbial community and SOC chemical composition were closely linked to light fraction organic C (LFC) and readily oxidizable C (ROC), respectively. Further, structural equation modeling and linear regression analysis revealed that SOC recalcitrance (negative effects) and C-degrading enzyme activities (positive effects) together mediate Rs rates; meanwhile, microbial community can indirect affect Rs rates through altering C-degrading enzyme activities. Conclusions: Agricultural soil abiotic properties (mainly labile C fractions, i.e., LFC and ROC) are altered by adding organic resources (i.e., manure and straw), the changes of which can promote soil microbial growth, enhance C-degrading microbial activity, and reduce SOC recalcitrance, and in turn accelerate Rs in GVP systems.
Carbon-nitrogen interactions in European forests and semi-natural vegetation - Part 1 : Fluxes and budgets of carbon, nitrogen and greenhouse gases from ecosystem monitoring and modelling
Sutton, Mark A. ; Flechard, Chris R. ; Ibrom, Andreas ; Skiba, Ute M. ; Vries, Wim De; Oijen, Marcel Van; Cameron, David R. ; DIse, Nancy B. ; Korhonen, Janne F.J. ; Buchmann, Nina ; Legout, Arnaud ; Simpson, David ; Sanz, Maria J. ; Aubinet, Marc ; Loustau, Denis ; Montagnani, Leonardo ; Neirynck, Johan ; Janssens, Ivan A. ; Pihlatie, Mari ; Kiese, Ralf ; Siemens, Jan ; Francez, Andre Jean ; Augustin, Jurgen ; Varlagin, Andrej ; Olejnik, Janusz ; Juszczak, Radoslaw ; Aurela, Mika ; Berveiller, Daniel ; Chojnicki, Bogdan H. ; Dämmgen, Ulrich ; Delpierre, Nicolas ; Djuricic, Vesna ; Drewer, Julia ; Dufrêne, Eric ; Eugster, Werner ; Fauvel, Yannick ; Fowler, David ; Frumau, Arnoud ; Granier, André ; Gross, Patrick ; Hamon, Yannick ; Helfter, Carole ; Hensen, Arjan ; Horvath, Laszlo ; Kitzler, Barbara ; Kruijt, Bart ; Kutsch, Werner L. ; Lobo-Do-Vale, Raquel ; Lohila, Annalea ; Longdoz, Bernard ; Marek, Michal V. ; Matteucci, Giorgio ; Mitosinkova, Marta ; Moreaux, Virginie ; Neftel, Albrecht ; Ourcival, Jean Marc ; Pilegaard, Kim ; Pita, Gabriel ; Sanz, Francisco ; Schjoerring, Jan K. ; Sebastià, Maria Teresa ; Sim Tang, Y. ; Uggerud, Hilde ; Urbaniak, Marek ; DIjk, Netty Van; Vesala, Timo ; Vidic, Sonja ; Vincke, Caroline ; Weidinger, Tamas ; Zechmeister-Boltenstern, Sophie ; Butterbach-Bahl, Klaus ; Nemitz, Eiko - \ 2020
Biogeosciences 17 (2020)6. - ISSN 1726-4170 - p. 1583 - 1620.
The impact of atmospheric reactive nitrogen (Nr) deposition on carbon (C) sequestration in soils and biomass of unfertilized, natural, semi-natural and forest ecosystems has been much debated. Many previous results of this dC=dN response were based on changes in carbon stocks from periodical soil and ecosystem inventories, associated with estimates of Nr deposition obtained from large-scale chemical transport models. This study and a companion paper (Flechard et al., 2020) strive to reduce uncertainties of N effects on C sequestration by linking multi-annual gross and net ecosystem productivity estimates from 40 eddy covariance flux towers across Europe to local measurement-based estimates of dry and wet Nr deposition from a dedicated collocated monitoring network. To identify possible ecological drivers and processes affecting the interplay between C and Nr inputs and losses, these data were also combined with in situ flux measurements of NO, N2O and CH4 fluxes; soil NO3 leaching sampling; and results of soil incubation experiments for N and greenhouse gas (GHG) emissions, as well as surveys of available data from online databases and from the literature, together with forest ecosystem (BASFOR) modelling. Multi-year averages of net ecosystem productivity (NEP) in forests ranged from 70 to 826 gCm2 yr1 at total wetCdry inorganic Nr deposition rates (Ndep) of 0.3 to 4.3 gNm2 yr1 and from 4 to 361 g Cm2 yr1 at Ndep rates of 0.1 to 3.1 gNm2 yr1 in short semi-natural vegetation (moorlands, wetlands and unfertilized extensively managed grasslands). The GHG budgets of the forests were strongly dominated by CO2 exchange, while CH4 and N2O exchange comprised a larger proportion of the GHG balance in short semi-natural vegetation. Uncertainties in elemental budgets were much larger for nitrogen than carbon, especially at sites with elevated Ndep where Nr leaching losses were also very large, and compounded by the lack of reliable data on organic nitrogen and N2 losses by denitrification. Nitrogen losses in the form of NO, N2O and especially NO3 were on average 27%(range 6 % 54 %) of Ndep at sites with Ndep < 1 gNm2 yr1 versus 65% (range 35 % 85 %) for Ndep > 3 gNm2 yr1. Such large levels of Nr loss likely indicate that different stages of N saturation occurred at a number of sites. The joint analysis of the C and N budgets provided further hints that N saturation could be detected in altered patterns of forest growth. Net ecosystem productivity increased with Nr deposition up to 2 2.5 gNm2 yr1, with large scatter associated with a wide range in carbon sequestration efficiency (CSE, defined as the NEP = GPP ratio). At elevated Ndep levels (> 2.5 gNm2 yr1), where inorganic Nr losses were also increasingly large, NEP levelled off and then decreased. The apparent increase in NEP at low to intermediate Ndep levels was partly the result of geographical cross-correlations between Ndep and climate, indicating that the actual mean dC=dN response at individual sites was significantly lower than would be suggested by a simple, straightforward regression of NEP vs. Ndep.