Nutrient recycling from sanitation and energy systems to the agroecosystem - Ecological research on case studies in Karagwe, Tanzania

Open cycles of organic carbon and nutrients cause soil degradation. Procedures such as ecological sanitation (EcoSan), bioenergy and Terra Preta practice (TPP) can contribute to closing nutrient cycles and may, in addition, sequester carbon. This paper introduces three projects in Karagwe, Tanzania, and their applied approach of integrated resource management to capture carbon and nutrients from different waste flows. Substrates derived from these case studies, biogas slurry, compost and CaSa-compost (containing biochar and sanitized human excreta), were assessed for their nutrient content by analysis of the total element composition. Evaluation focused on potential impacts of the tested amendments on the nutrient availability in the soil as well as on the local soil nutrient balance. Results revealed that all substrates show appropriate fertilizing potential compared to literature, especially for phosphorus (P). CaSa-compost was outstanding, with a total P concentration of 1.7 g dm-3 compared to 0.5 and 0.3 g dm-3 in compost and biogas slurry respectively. Furthermore, these soil amendments may reduce acidity of the soil, with a calculated liming effect of 3.4, 2.6 and 7.8 kg CaO for each kg of nitrogen added for biogas slurry, compost and CaSa-compost respectively. To offset negative P balances in Karagwe, about 8100, 6000 and 1600 dm3 ha-1 are required for biogas slurry, compost and CaSa-compost respectively. We conclude that especially CaSa-compost might offer immediate positive effects to crop production and nutrient availability in the soil

Species traits and geomorphic setting as drivers of global soil carbon stocks in seagrass meadows

Unidad de excelencia María de Maeztu CEX2019-000940-MOur knowledge of the factors that can influence the stock of organic carbon (OC) that is stored in the soil of seagrass meadows is evolving, and several causal effects have been used to explain the variation of stocks observed at local to national scales. To gain a global-scale appreciation of the drivers that cause variation in soil OC stocks, we compiled data on published species-specific traits and OC stocks from monospecific and mixed meadows at multiple geomorphological settings. Species identity was recognized as an influential driver of soil OC stocks, despite their large intraspecific variation. The most important seagrass species traits associated with OC stocks were the number of leaves per seagrass shoot, belowground biomass, leaf lifespan, aboveground biomass, leaf lignin, leaf breaking force and leaf OC plus the coastal geomorphology of the area, particularly for lagoon environments. A revised estimate of the global average soil OC stock to 20 cm depth of 15.4 Mg C ha−1 is lower than previously reported. The largest stocks were still recorded in Mediterranean seagrass meadows. Our results specifically identify Posidonia oceanica from the Mediterranean and, more generally, large and persistent species as key in providing climate regulation services, and as priority species for conservation for this specific ecosystem service

Nonhuman primates across sub-Saharan Africa are infected with the yaws bacterium Treponema pallidum subsp. pertenue

Dear Editor, The bacterium Treponema pallidum (TP) causes human syphilis (subsp. pallidum; TPA), bejel (subsp. endemicum; TEN), and yaws (subsp. pertenue; TPE) (1). Although syphilis has reached a worldwide distribution (2), bejel and yaws have remained endemic diseases. Bejel affects individuals in dry areas of Sahelian Africa and Saudi Arabia, whereas yaws affects those living in the humid tropics (1). Yaws is currently reported as endemic in 14 countries, and an additional 84 countries have a known history of yaws but lack recent epidemiological data (3,4). Although this disease was subject to global eradication efforts in the mid-20th century, it later reemerged in West Africa, Southern Asia, and the Pacific region (5). New large-scale treatment options triggered the ongoing second eradication campaign, the goal of which is to eradicate yaws globally by 2020 (5). References: (1) Giacani, L. & Lukehart, S.A. The endemic treponematoses. Clin. Microbiol. Rev. 27, 89–115 (2014). (2) Arora, N. et al. Origin of modern syphilis and emergence of a pandemic Treponema pallidum cluster. Nat. Microbiol. 2, 16245 (2016). (3) Marks, M. Yaws: towards the WHO eradication target. Trans. R Soc. Trop. Med. Hyg. 110, 319–320 (2016). (4) World Health Organization. Eradication of yaws: procedures for verification and certification of interruption of transmission (World Health Organization, Geneva, 2018). (5) Asiedu, K., Fitzpatrick, C. & Jannin, J. Eradication of yaws: historical efforts and achieving WHO’s 2020 target. PLoS Negl. Trop. Dis. 8, e3016 (2014)

Toward a Generalizable Framework of Disturbance Ecology Through Crowdsourced Science

© 2021 Graham, Averill, Bond-Lamberty, Knelman, Krause, Peralta, Shade, Smith, Cheng, Fanin, Freund, Garcia, Gibbons, Van Goethem, Guebila, Kemppinen, Nowicki, Pausas, Reed, Rocca, Sengupta, Sihi, Simonin, Słowiński, Spawn, Sutherland, Tonkin, Wisnoski, Zipper and Contributor Consortium.Disturbances fundamentally alter ecosystem functions, yet predicting their impacts remains a key scientific challenge. While the study of disturbances is ubiquitous across many ecological disciplines, there is no agreed-upon, cross-disciplinary foundation for discussing or quantifying the complexity of disturbances, and no consistent terminology or methodologies exist. This inconsistency presents an increasingly urgent challenge due to accelerating global change and the threat of interacting disturbances that can destabilize ecosystem responses. By harvesting the expertise of an interdisciplinary cohort of contributors spanning 42 institutions across 15 countries, we identified an essential limitation in disturbance ecology: the word ‘disturbance’ is used interchangeably to refer to both the events that cause, and the consequences of, ecological change, despite fundamental distinctions between the two meanings. In response, we developed a generalizable framework of ecosystem disturbances, providing a well-defined lexicon for understanding disturbances across perspectives and scales. The framework results from ideas that resonate across multiple scientific disciplines and provides a baseline standard to compare disturbances across fields. This framework can be supplemented by discipline-specific variables to provide maximum benefit to both inter- and intra-disciplinary research. To support future syntheses and meta-analyses of disturbance research, we also encourage researchers to be explicit in how they define disturbance drivers and impacts, and we recommend minimum reporting standards that are applicable regardless of scale. Finally, we discuss the primary factors we considered when developing a baseline framework and propose four future directions to advance our interdisciplinary understanding of disturbances and their social-ecological impacts: integrating across ecological scales, understanding disturbance interactions, establishing baselines and trajectories, and developing process-based models and ecological forecasting initiatives. Our experience through this process motivates us to encourage the wider scientific community to continue to explore new approaches for leveraging Open Science principles in generating creative and multidisciplinary ideas.This research was supported by the U.S. Department of Energy (DOE), Office of Biological and Environmental Research (BER), as part of Subsurface Biogeochemical Research Program’s Scientific Focus Area (SFA) at the Pacific Northwest National Laboratory (PNNL). PNNL is operated for DOE by Battelle under contract DE-AC06-76RLO 1830

The association between frailty and MRI features of cerebral small vessel disease

Abstract: Frailty is a common syndrome in older individuals that is associated with poor cognitive outcome. The underlying brain correlates of frailty are unclear. The aim of this study was to investigate the association between frailty and MRI features of cerebral small vessel disease in a group of non-demented older individuals. We included 170 participants who were classified as frail (n = 30), pre-frail (n = 85) or non-frail (n = 55). The association of frailty and white matter hyperintensity volume and shape features, lacunar infarcts and cerebral perfusion was investigated by regression analyses adjusted for age and sex. Frail and pre-frail participants were older, more often female and showed higher white matter hyperintensity volume (0.69 [95%-CI 0.08 to 1.31], p = 0.03 respectively 0.43 [95%-CI: 0.04 to 0.82], p = 0.03) compared to non-frail participants. Frail participants showed a non-significant trend, and pre-frail participants showed a more complex shape of white matter hyperintensities (concavity index: 0.04 [95%-CI: 0.03 to 0.08], p = 0.03; fractal dimensions: 0.07 [95%-CI: 0.00 to 0.15], p = 0.05) compared to non-frail participants. No between group differences were found in gray matter perfusion or in the presence of lacunar infarcts. In conclusion, increased white matter hyperintensity volume and a more complex white matter hyperintensity shape may be structural brain correlates of the frailty phenotype

Research and Design of a Routing Protocol in Large-Scale Wireless Sensor Networks

无线传感器网络，作为全球未来十大技术之一，集成了传感器技术、嵌入式计算技术、分布式信息处理和自组织网技术，可实时感知、采集、处理、传输网络分布区域内的各种信息数据，在军事国防、生物医疗、环境监测、抢险救灾、防恐反恐、危险区域远程控制等领域具有十分广阔的应用前景。 本文研究分析了无线传感器网络的已有路由协议，并针对大规模的无线传感器网络设计了一种树状路由协议，它根据节点地址信息来形成路由，从而简化了复杂繁冗的路由表查找和维护，节省了不必要的开销，提高了路由效率，实现了快速有效的数据传输。 为支持此路由协议本文提出了一种自适应动态地址分配算——ADAR（AdaptiveDynamicAddre...As one of the ten high technologies in the future, wireless sensor network, which is the integration of micro-sensors, embedded computing, modern network and Ad Hoc technologies, can apperceive, collect, process and transmit various information data within the region. It can be used in military defense, biomedical, environmental monitoring, disaster relief, counter-terrorism, remote control of haz...学位：工学硕士院系专业：信息科学与技术学院通信工程系_通信与信息系统学号：2332007115216

Abfälle wertschätzen : eine integrierte Systemanalyse der Bioenergienutzung, ökologischen Sanitärversorgung und des Bodenfruchtbarkeitsmanagements in kleinbäuerlicher Landwirtschaft in Karagwe, Tansania

My dissertation had as its starting point the intention of two Tanzanian farmer's initiatives and their German partners to disseminate sustainable cooking and sanitation technologies to smallholder households in Karagwe District, in northwest Tanzania (TZ). These locally developed and adapted technologies include improved cook stoves, such as microgasifiers, and a system combining biogas digesters and burners for cooking, as well as urine-diverting dry toilets and thermal sterilization/pasteurization for ecological sanitation (EcoSan). Currently, the most common combination of technologies used for cooking and sanitation in Karagwe smallholdings is a three-stone fire and pit latrine. Switching to the new alternatives could potentially lead to (i) optimized resource consumption, (ii) lower environmental emissions, and (iii) a higher availability of domestic residues for soil fertility management. The latter include biogas slurry from anaerobic digestion, powdery biochar from microgasifiers, and sanitized human excreta from EcoSan facilities. These residues are `locally available resources' that can be used for on-farm material cycling. Using TZ as an example and local initiatives as case studies, I have examined the triple nexus of `energy-sanitation-agriculture' with an interdispicplinary multi-method approach. Empirically and analytically, my results shed light on agronomic potentials of an intersectional resource management for circular economies and on values of material cycling in smallholder farming systems as well as on weak points in the system, from both ecological and socio-economic perspectives. As one example, I demonstrated that all the treatments analyzed could enhance crop productivity up to 400 % in a short-term experiment on the local Andosol. [Please see longer Abstract in my thesis for the summary of more results.] Ultimately, I conclude that a particularly promising way of implementing an intersectional resource management around the nexus energy-sanitation-agriculture is the combination of using microgasifiers for cooking and implementing EcoSan, in addition to the combined recycling of biochar and sanitized excreta in `CaSa-compost'. This approach can achieve multiple goals including: (i) increase access to fertilizers, (ii) decrease nutrient depletion and acidification of soils, (iii) increase food production and farm income, (iv) reduce resource consumption, and (v) reduce environmental impacts, like global warming or eutrophication. For many smallholder farmers in Sub-Saharan Africa, this practical approach thus represents a viable exit strategy from the vicious circle of soil acidity and P-scarcity leading to insufficient production of food crops, which in turn leads to insufficient production of residual matter for soil fertility management and improvement.Ausgangspunkt meiner Dissertation war das Vorhaben zweier tansanischer Initiativen und ihrer deutschen Partner*innen, nachhaltige Koch- und Sanitärtechnologien für kleinbäuerliche Haushalte im Bezirk Karagwe im Nordwesten Tansanias zu verbreiten. Die vor Ort entwickelten und an die lokalen Bedingungen angepassten Technologien umfassen verbesserte Herde, wie Mikrovergaser, und ein System aus Kleinst-Biogas-Anlage und -Kocher, sowie einen Ansatz zur ökologischen Sanitärversorgung (ecological sanitation, EcoSan) als Kombination aus Trockentrenntoilette mit thermischer Hygienisierung der Fäkalien. Die aktuell üblichste Kombination von Koch- und Sanitär-Technologien in kleinbäuerlichen Haushalten in Karagwe ist Drei-Stein-Feuer und Gruben-Latrine. Ein Technologiewechsel hin zu den neuen Alternativen führt potenziell zu (i) einer optimierten Ressourcennutzung, (ii) niedrigeren Emissionen in die Umwelt und (iii) einer höheren Verfügbarkeit von Reststoffen in den Haushalten und auf der Farm. Zu diesen Reststoffen gehören Gärreste aus der anaerober Fermentation, pulverige Biokohle aus Mikrovergasern und pasteurisierte menschliche Fäkalien aus EcoSan-Anlagen. Diese „lokal verfügbaren Ressourcen“ können für den Aufbau einer landwirtschaftlichen Kreislaufwirtschaft genutzt werden. In meiner Arbeit habe ich mit einem interdisziplinären Mehr-Methoden-Ansatz die Verflechtung von „Energiebereitstellung-Sanitärversorgung-Landwirtschaft“ am Beispiel kleinbäuerliche Haushalte in Tansania betrachtet. Die Projekte in Karagwe dienten mir dabei als Fallstudien. Meine Ergebnisse beleuchten auf empirische und analytische Weise die agronomischen Potenziale eines Sektoren übergreifenden Ressourcenmanagement für Kreislaufwirtschaften, den Wert von Stoffkreisläufen in kleinbäuerlichen Systemen sowie Schwachstellen im System aus ökologischer und sozio-ökonomischer Perspektive. Als nur ein Beispiel, konnte ich im Kurzzeit-Feldversuch zeigen, dass die untersuchten Dünge-Verfahren die Pflanzenproduktivität um bis zu 400 % verbessern können. [Eine weitere Zusammenfassung meiner Ergebnisse findet sich im Abstract zu Beginn der Arbeit.] Schlussendlich ist eine Kern-Schlussfolgerung meiner Arbeit, dass besonders die Kombination aus Mikrovergaser zum Kochen und EcoSan, gekoppelt mit der konsequenten und gemeinsamen Rückführung von Biokohle und hygienisierten menschlichen Fäkalien in „CaSa-Komposts“, ein vielversprechendes, Sektoren-übergreifenden Ressourcenmanagement darstellt. Mit diesem Ansatz können gleichzeitig mehrere Ziele erreicht werden, nämlich: (i) Verbesserung des Zugangs zu Dünger durch Eigenproduktion, (ii) Sanierung der ausgelaugten und versauerten Böden, (iii) positiver Beitrag zur Ernährungssouveränität und Einkommensgrundlage der Kleinbauer*innen, (iv) Senkung des Ressourcenverbrauchs, und (v) Reduktion der negativen Umweltwirkungen wie Treibhausgasemissionen und Eutrophierung. Dieser praktische Ansatz ist daher eine geeignete Strategie, um einen Teufelskreis zu durchbrechen, in dem sich viele Kleinbauer*innen in Afrika südlich der Sahara befinden. Dabei führen Bodenversauerung und P-Knappheit zu einer unzureichenden Produktion von Nahrungsmitteln, und somit auch zu einer unzureichenden Produktion von pflanzlichen Reststoffen, welche wiederum zum Erhalt bzw. zur Verbesserung der Bodenfruchtbarkeit benötigt werden

A Multi-Criteria Approach for Assessing the Sustainability of Small-Scale Cooking and Sanitation Technologies

To reduce the consumption of firewood for cooking and to realise recycling-driven soil fertility management, three projects in Northwest Tanzania aim to provide the local smallholder community with cooking and sanitation alternatives. The present study proposes an integrated approach to assess the sustainability of the small-scale cooking and sanitation technologies. Based on the multi-criteria decision support approach (MC(D)A), we developed a decision-specific, locally adapted, and participatory assessment tool: the Multi-Criteria Technology Assessment (MCTA). Pre-testing of the tailored tool was set up with representatives of Tanzanian and German partners of case study projects. From a methodological perspective, we conclude that the MCTA uses a set of relevant criteria to realise a transparent and replicable computational Excel-tool. The combination of MC(D)A for structuring the assessment with analytical methods, such as Material Flow Analysis, for describing the performance of alternatives is a promising path for designing integrated approaches to sustainability assessments of technologies. Pre-testing of the tool served as a proof-of-concept for the general design of the method. Future applications and adjustments of the MCTA require the inclusion of end-users, a reasonable and participatory reduction of criteria, and an increase of feedback loops and group discussions between participants and the facilitator to support a common learning about the technologies and thorough understanding of the perspectives of participants

Recycling Improves Soil Fertility Management in Smallholdings in Tanzania

Residues from bioenergy and ecological sanitation (EcoSan) can be utilized to sustain soil fertility and productivity. With regard to certain cooking and sanitation technologies used in smallholder households (hh), we systematically analyzed how utilization of the respective potentials to recover residues for farming affects (i) soil nutrient balances, (ii) the potential for subsistence production of composts, and (iii) environmental emissions. On the example of an intercropping farming system in Karagwe, Tanzania, we studied specific farming practices including (1) current practices of using standard compost only; (2) a combination of using biogas slurry, urine, and standard compost; (3) a combination of using so-called “CaSa-compost” (containing biochar and sanitized human excreta, Project “Carbonization and Sanitation”), urine, and standard compost. The system analysis combines a soil nutrient balance (SNB) with material flow analysis (MFA). Currently, nitrogen (N) and phosphorus (P) are depleted by −54 ± 3 and −8 ± 1 kg∙ha−1∙year−1, respectively. Our analysis shows, however, a clear potential to reduce depletion rates of N, and to reverse the SNB of P, to bring about a positive outcome. Composts and biogas slurry supply sufficient P to crops, while urine effectively supplements N. By using resources recovered from cooking and sanitation, sufficient compost for subsistence farming may be produced. Human excreta contribute especially to total N and total P in CaSa-compost, whilst biochar recovered from cooking with microgasifier stoves adds to total carbon (C) and total P. We conclude that the combined recycling of household residues from cooking and from sanitation, and CaSa-compost in particular, is especially suitable for sustainable soil management, as it mitigates existing P-deficiency and soil acidity, and also restores soil organic matter

Anodal Transcranial Direct Current Stimulation (tDCS) Over the Right Primary Motor Cortex (M1) Impairs Implicit Motor Sequence Learning of the Ipsilateral Hand

Motor sequence learning is associated with the activation of bilateral primary motor cortices (M1). While previous data support the hypothesis that the contralateral M1 is causally involved in the acquisition as well as early consolidation of a motor sequence, the functional significance of the ipsilateral M1 has yet to be solved. Transcranial direct current stimulation (tDCS) allows the non-invasive modulation of cortical excitability. Anodal tDCS applied to the left M1 has been shown to facilitate implicit motor sequence learning of the right hand most likely due to increased excitability. The present study aims at characterizing the functional contribution of the ipsilateral (right) M1 on implicit motor sequence learning of the right hand. To this end, 24 healthy, right-handed subjects received anodal and sham tDCS to the right M1 in a counterbalanced order. Stimulation started 8 min prior to training on a variant of the serial reaction time task (SRTT) with the right hand and persists over the entire training period. The SRTT comprised a fixed eight-digit sequence. A random pattern served as control condition. Reaction times were assessed before and at the end of the acquisition (EoA) immediately after training on the SRTT. The analysis revealed significantly faster reaction times of both hands independent of tDCS condition in sequential trials. However, the gain of reaction times was significantly smaller following anodal as compared to sham tDCS. The data suggest that anodal tDCS applied to the right M1 impairs implicit motor sequence learning of both hands. The underlying mechanism likely involves alterations of the interaction between bilateral M1