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Global relationships between crop yield and pollinator abundance
No full textPollinators are estimated to benefit the reproduction of three-quarters of global leading crop species and contribute to 3%–8% of the total global food production. Ongoing declines in pollinator populations have raised concerns about repercussions for food security. Thus, there is a need to better understand how agricultural yields depend on pollinator abundance. Here, we established yield–pollinator relationships for 24 crops, capitalizing on a recently published global database with paired records of crop yield and pollinator abundance. We used linear mixed-effects modelling to relate relative yields to total pollinator abundance, accounting for differences in climate and farming practices. Overall, we found a positive relationship between crop yield and pollinator abundance, which was modified by management practice and climate zone. At a given pollinator abundance, yields were significantly higher for conventional than for organic farms, while yields in temperate regions were significantly higher than those in tropical regions. In addition, we found a positive relationship between relative yield and pollinator abundance for 21 out of the 24 crop species, indicating that variability in pollinator numbers across agricultural fields has consequences for crop pollination. Synthesis and applications. Our global and context-specific yield–pollinator relationships, based on the best available data to date, represent a key step towards quantitative models for assessing the degree of pollination sufficiency worldwide. We believe that this will increase the robustness of pollination model outputs and better inform the transition towards pollinator-friendly agricultural practices
Securing the control of digital beamforming
No full textWith the increase of devices connected to 5G services, the importance of tuning User Equipment (UE) to their assigned frequency slot becomes increasingly vital. This paper approached this issue by securing the control signals sent through a Serial Peripheral Interface (SPI) in digital beamforming radios. This was done by securing three distinct components: the transmitting end of the channel, the transmission medium, and the receiving end of the channel. To secure the transmitter, a module was created that monitors transmitted messages to ensure correct operation. For the security of the transmission medium, a comparison study was performed between different error detecting and correcting algorithms against the authors' own solution comparing which alternatives were more effective at reducing the errors on a transmission line. For the receiving end, a dynamic lock-and-key system was implemented to make sure that the radios know that they are connected to a legitimate device. These three components were simulated and evaluated individually to ensure that each one provided its part of the secure system, and a post-synthesis simulation of a system with all three solutions was then performed to show that these aspects together can create a cohesive secure system
System Integrity Protection Schemes for increased capacity – a Nordic perspective
No full textThis article describes some of the findings from the ongoing Swedish research project “System Integrity Protection Schemes for added transfer capacity” (SPS4SE). The focus of the SPS4SE project has been to gather knowledge on how System Integrity Protection Schemes (SIPS) can be utilized to support a sustainable development of the Swedish power grid and the Nordic power system
Biomarkers for the Early Detection of Pancreatic Ductal Adenocarcinoma
No full textPancreatic ductal adenocarcinoma has one of the worst survival rates among adult cancers, with only 11% in the United States surviving five years after diagnosis. The majority of patients are diagnosed with late-stage disease, since early-stage pancreatic ductal adenocarcinoma is typically either asymptomatic or presents with non-specific symptoms. Pancreatic ductal adenocarcinoma thus remains a highly fatal disease. Today, surgical resection (removal of the pancreas) is the only potentially curative modality of treatment available. Detecting pancreatic cancer lesions early enough to perform surgery is, however, beset with difficulties. Nevertheless, the timeline of progression from low-grade precursor lesions to invasive cancer does offer a window of opportunity to detect the disease earlier than is currently possible. By providing physicians with actionable information early enough for the cancer to be removed surgically, the overall 5-year pancreatic ductal adenocarcinoma survival rate could increase from 11% to over 50%. In this chapter, we describe the development and clinical implementation of a proteomic, multi-biomarker blood test for the early detection of pancreatic ductal adenocarcinoma
En bardval i vendeltida Västra Karaby
No full textDenna artikel behandlar fyndet av en kota från en bardval som påträffades under utgrävningarna av Västra Karaby, en vendeltida boplats i västra Skåne. Fynd av bardvalar i skånska järnåldersboplatser är mycket sällsynta. I artikeln diskuteras kotans proveniens, kronologiska tillhörighet och betydelse för förståelsen av boplatsen. En taxonomisk bestämning av kotan har gjorts genom den benkemiska peptidbaserade tekniken Zooarchaeology by Mass Spectrometry (ZooMS), till antingen grönlandsval eller nordkapare, båda tillhörande familjen rätvalar (Balaenidae). Dessa valar rör sig sällan ner till södra delen av Norra Havet eller Öresund. I detta fall är fyndet tydligt ett resultat av import, eftersom Västra Karaby är beläget inåt land och inte heller vid direkt anslutning till vattendrag. Bardvalkotan relateras i denna artikel till handel med och hantverk i bardvalben, såsom spelpjäser. Vendeltida Västra Karaby ingick troligtvis i ett långväga handelsnätverk med råmaterial och resurser, där bland annat valben ingick
Including the phosphorus cycle into the LPJ-GUESS dynamic global vegetation model (v4.1, r10994) – global patterns and temporal trends of N and P primary production limitation
No full textPhosphorus (P) is a critical macronutrient for plant growth, often limiting plant production in areas where plant demand is higher than soil supply. In contrast to nitrogen (N), P cannot be sourced from the atmosphere; therefore, where it is rare, it becomes a strong constraint on primary production. Due to this, most dynamic global vegetation models (DGVMs) are incorporating a prognostic P cycle in addition to N, improving their ability to correctly predict stocks and fluxes of carbon and how climate change may impact N and/or P limitations to soil processes and plant productivity.We included the P cycle into an individual-based DGVM, Lund–Potsdam–Jena General Ecosystem Simulator (LPJ-GUESS, v4.1, r10994), in order to improve model performance with regard to observations of vegetation and soil N and P stocks and fluxes in comparison to the N-only (LPJ-GUESS-CN) model version. The new model version (LPJ-GUESS-CNP v1.0) includes soil organic P dynamics, P limitation of organic matter decomposition, P deposition, temperature- and humidity-dependent P weathering, plant P demand and uptake, and P limitations to photosynthesis. Using the CNP version of LPJ-GUESS, we also estimated global spatial patterns of nutrient limitation to plant growth as well as the temporal change in plant N and P limitation during the 20th and early 21st century, evaluating the causes for these temporal shifts.We show that including the P cycle significantly reduces simulated global vegetation and soil C and N stocks and fluxes, in particular in tropical regions. The CNP model simulation improves the fit to global biomass observations in relation to the CN simulation. The CNP model predicts predominant P limitation of plant growth in the tropics, and N limitation in the temperate, boreal, and high-altitude tropical regions. The CNP model also correctly predicted the global magnitude (∼50 PgP) and the spatial pattern of total organic P stocks. P-limited regions cover less land surface area (46 %) than N-limited ones but are responsible for 57 % of the global gross primary productivity (GPP) and 68 % of vegetation biomass, while N-limited regions store a larger portion of total carbon stocks (55.9 %). Finally, the model shows that globally, primary production limitation to N availability decreased and limitation to P increased from 1901 to 2018, with N being more responsive to temperature and P than CO2 changes. We conclude that including the P cycle in models like LPJ-GUESS is crucial for understanding global-scale spatial and temporal patterns in nutrient limitation and improving the simulated carbon stocks and fluxes
Contested mangroves : land struggles and the gendered and racialized geographies of climate change
No full textClimate change manifests historically and spatially in uneven geographies of responsibility, vulnerability and adaptation. Urban and tourism expansion on the city’s margins in Cartagena, Colombia, has led to the criminalization and dispossession of land, water, and mangroves in Black communities who resist racism, ecological degradation, and climate vulnerability. We analyse how Black women in marginalized communities adapt, integrate, and reshape climate change actions within a history of territorial defence and gendered and racialized dispossession. The case study of Black women mangrove-planters demonstrates how disputes over mangrove reveal intricate connections between land struggles and climate justice. Our findings also point to how the current adaptation regime depends upon the gendered and racialized labour of local communities, while furthering their marginalization
Börringe genom bygdefotografens lins : Om Lennart Börnfors arbete med Martin Svenssons samling
No full textEstimating erosion resistance of vegetated sea dike embankments through in situ experiments
No full textThrough in situ experiments, this study investigated the erosion resistance of a prototype dike with different vegetation and soil sections built on the Falsterbo peninsula, Sweden. A gravity-driven wave impact simulator was used to simulate waves breaking on the dike. Two sandy soils and three vegetation types (standard grass, biodiverse seed mixture, and hay) were tested for this study. In general, the study showed consistency in the results between the replications and in comparison to former studies. Thus, initially developed for laboratory experiments, the methodology can be transferred to in situ experiments on existing dikes. The study showed comparable results for higher biodiverse vegetation cover and standard grass regarding the resistance to wave impact. The importance of not only root but also soil parameters could be confirmed. A higher resistance was found with higher root densities and lower fine fractions in the soil. Also, a higher forb diversity resulted in larger root densities. Future studies could build on the present findings by conducting a systematic investigation to gain deeper insights into the impact of vegetation and soil properties
