Temporal and Spatial Impact of Human Cadaver Decomposition on Soil Bacterial and Arthropod Community Structure and Function

As vertebrate carrion decomposes, there is a release of nutrient-rich fluids into theunderlying soil, which can impact associated biological community structure andfunction. How these changes alter soil biogeochemical cycles is relatively unknown and may prove useful in the identification of carrion decomposition islands that have long lasting, focal ecological effects. This study investigated the spatial (0, 1, and 5 m) and temporal (3–732 days) dynamics of human cadaver decomposition on soil bacterial and arthropod community structure and microbial function. We observed strong evidence of a predictable response to cadaver decomposition that varies over space for soil bacterial and arthropod community structure, carbon (C) mineralization and microbial substrate utilization patterns. In the presence of a cadaver (i.e., 0 m samples), the relative abundance of Bacteroidetes and Firmicutes was greater, while the relative abundance of Acidobacteria, Chloroflexi, Gemmatimonadetes, and Verrucomicrobia was lower when compared to samples at 1 and 5 m. Micro-arthropods were more abundant (15 to 17-fold) in soils collected at 0 m compared to either 1 or 5 m, but overall, micro-arthropod community composition was unrelated to either bacterial community composition or function. Bacterial community structure and microbial function also exhibited temporal relationships, whereas arthropod community structure did not. Cumulative precipitation was more effective in predicting temporal variations in bacterial abundance and microbial activity than accumulated degree days. In the presence of the cadaver (i.e., 0 m samples), the relative abundance of Actinobacteria increased significantly with cumulative precipitation. Furthermore, soil bacterial communities and C mineralization were sensitive to the introduction of human cadavers as they diverged from baseline levels and did not recover completely in approximately 2 years. These data are valuable for understanding ecosystem function surrounding carrion decomposition islands and can be applicable to environmental bio-monitoring and forensic sciences

Ecotone conditions along pinon-juniper and ponderosa pine elevational ranges, Jemez Mountains, NM

While climate variability is endemic to Southwest North America (SWNA), mounting evidence indicates the region is undergoing significant warming and becoming increasingly arid. Species are at or near their physiological limits at ecotone boundaries and are therefore particularly sensitive to climate change. Drought and warming associated tree mortality has been particularly acute in the semiarid forests and woodlands of the Jemez Mountains, New Mexico, USA, where ponderosa pine forests (Pinus ponderosa var. scopulorum) and piñon--juniper woodlands (Pinus edulis and Juniperus monosperma) have been subject to cambium-feeding pine beetle (Dendroctonus spp., Ips spp) attacks and increased wildfire activity and severity. Grazing and fire suppression have also impacted fire regimes leading to altered species composition and distribution. Projected warming and drought conditions in the 21st century will likely foster rapid (i.e. \u3c5 year) ecotone shifts in semiarid ponderosa pine forests and piñon-juniper woodlands. This study analyzed ponderosa pine ecotone characteristics within a 2100 to 2200 m. range of the Vallecita watershed of the Jemez Mountains. Identification of sample sites was accomplished using remote sensing Landsat imagery, a moderate resolution earth observation data, coupled with a Geographic Information System (GIS) embedded semi--automated land cover classification method for raster-based analysis. Field procedures devised for this study determined past vegetation elements, current vegetation structure and composition, and present successional trajectory. The results of this research established baseline conditions and suggest the study area is undergoing a climate generated compositional shift from ponderosa pine dominated sites to piñon-juniper woodlands. Analysis of log and snag decay classes showed evidence of recent mortality and indicated ponderosa pine was formerly the climax species in sampled areas. As piñon-juniper woodlands exhibit different fire characteristics than ponderosa pine forests, fire behavior will likely change if trends continue

Nutrient Availability Controls the Impact of Mammalian Herbivores on Soil Carbon and Nitrogen Pools in Grasslands

Grasslands are subject to considerable alteration due to human activities globally, including widespread changes in populations and composition of large mammalian herbivores and elevated supply of nutrients. Grassland soils remain important reservoirs of carbon (C) and nitrogen (N). Herbivores may affect both C and N pools and these changes likely interact with increases in soil nutrient availability. Given the scale of grassland soil fluxes, such changes can have striking consequences for atmospheric C concentrations and the climate. Here, we use the Nutrient Network experiment to examine the responses of soil C and N pools to mammalian herbivore exclusion across 22 grasslands, under ambient and elevated nutrient availabilities (fertilized with NPK + micronutrients). We show that the impact of herbivore exclusion on soil C and N pools depends on fertilization. Under ambient nutrient conditions, we observed no effect of herbivore exclusion, but under elevated nutrient supply, pools are smaller upon herbivore exclusion. The highest mean soil C and N pools were found in grazed and fertilized plots. The decrease in soil C and N upon herbivore exclusion in combination with fertilization correlated with a decrease in aboveground plant biomass and microbial activity, indicating a reduced storage of organic matter and microbial residues as soil C and N. The response of soil C and N pools to herbivore exclusion was contingent on temperature – herbivores likely cause losses of C and N in colder sites and increases in warmer sites. Additionally, grasslands that contain mammalian herbivores have the potential to sequester more N under increased temperature variability and nutrient enrichment than ungrazed grasslands. Our study highlights the importance of conserving mammalian herbivore populations in grasslands worldwide. We need to incorporate local‐scale herbivory, and its interaction with nutrient enrichment and climate, within global‐scale models to better predict land–atmosphere interactions under future climate change

The Scrovegni Chapel in Padua: flooding causes and countermeasures

Analisi delle cause dell'allagamento della zona Scrovegni, nella città di Padova, ed eventuali soluzion

Effect of grazing in Norwegian outfields related to the quantity and quality of soil organic carbon and other soil properties

Utilization of the outfield for grazing have long traditions in Norway. Not only as a pasture, but also mowed to provide food for the winter (Rekdal & Angeloff, 2021). From 1949 to 1999, grazing in Norway changed from being dominated by livestock to being equally grazed between wild herbivore and livestock (Austrheim et al., 2011). This change in usage has led several of the semi-natural habitat types to end up on the red list of the Norwegian Biodiversity Information Centre, such as Semi-natural meadow and Hayfields (Hovstad, 2018). Therefore, grazing in outfield areas in Norway are desired as a way of keeping the cultural landscape. Resent years events particularly, in addition to a growing concern about the world’s food situation has increased the interest for local food production. The latest analysis of grazing and the outfield suitable of such, indicates that Norway’s unused potential in outfield is about 55% (Rekdal & Angeloff, 2021). In addition to recent years events, the world is facing changes in climate. Still debated on how extensive and where the greatest changes will appear, a change in food production are required to undergo adjustments. Knowledge of management and “best practice” models are therefore crucial. Also in Norway, information on how the soil in outfields are affected by grazing is as important than ever. In this thesis five locations who differs in climate and vegetation are sampled. All these locations are grazed during the summer season by suckler cows which is a part of the Norwegian meat production. Throughout this thesis grazing was not found to significantly affect the SOC-stock, SOC concentration or the thickness of the organic layer. While grazing was found to significantly decrease the HWEC-stock in all mineral layers and the CN-ratio in the organic layer. The decrease in the HWEC-stock is suggested caused by removal of organic matter by grazers. The basis for this assumption is partly the combination of the significant decline in HWECstocks and difference between grazed and non-grazed site in the thickness of the organic layer mean values (not significant). In addition, the CN ratio was found to significantly decrease under grazing in the organic layer. The HWEC-stock is viewed as a measure of the labile fraction (Dong et al., 2021), and is a useful indicator of the soil quality in soil-plant ecosystems (Ghani et al., 2003). The form and behaviour of the SOM and SOC is fully reliant on microbial mass (Bhattacharyya et al., 2022), and a decrease of the HWEC might therefor be a sign that a decline of microbial biomass pool (Ghani et al., 2003) are taking place. Since a significant decrease were found between the grazed site and the control sites (non-grazed) it might be an early indicator of degradation of the soil structure. A significant increase in bulk density between sites in the two top layers (the organic layer, mineral 0-10 cm) were found for all locations. In accordance with other studies on grazing effects (Byrnes et al., 2018; Martinsen et al., 2012; Piñeiro et al., 2010), it was concluded that the pastures were influenced by the grazing animals. On the background of different utilizing periods and grazer densities, the management of the pastures is suggested to might be influencing the HWEC-stock. Amongst the tested factors related to geography and effect on the SOC-stock, only MAT were found significant. Precipitation and content of fine texture quantity were not found to significantly effect SOCstocks. Therefore, geography was found somewhat related to the SOC-stock. Only Mg-stock had a significant difference between sites. Grazing was not found to significantly affect the soil’s pH. No plausible explanation for this significant result was found. The other macronutrient stocks were not found to significantly change with grazing.Beiting i utmark har lange tradisjoner i Norge. Ikke bare er utmarka benyttet som beite, men ble før også slått for å skaffe dyrene mat til vinteren (Rekdal & Angeloff, 2021). Fra 1949 til 1999 endret beite i Norge seg fra å være dominert av husdyr til å bli likt beitet mellom ville dyr og husdyr (Austrheim et al., 2011). Denne bruksendringen har ført til at flere av de semi-naturlige naturtypene har havnet på rødlista til Artsdatabanken, som for eksempel Semi-naturlig eng og slåttemark (Hovstad, 2018). Beiting som en måte å opprettholde kulturlandskapet er en av grunnene til at beiting i den norske utmarka er ønsket. Med tanke på de siste årenes begivenheter, i tillegg til en økende bekymring for verdens matsituasjon har interessen for lokal matproduksjon økt. Den siste analysen utført på beitebruk og utmarkas egnethet for dette, indikerer at Norges ubrukte potensial i utmark er om lag 55 % (Rekdal & Angeloff, 2021). Verden står i tillegg til de siste årenes hendelser på trappene av klimaendringer. Omfang og område for hvor været vil endres mest drastisk er usikkert, men matproduksjonen vil mest sannsynlig uansett måtte omstilles og berede seg på disse endringene. Kunnskap om forvalting og «best practice»-modeller er derfor avgjørende. Kanskje viktigere enn noen gang, også i Norge, er informasjon om hvordan jorda i utmark påvirkes av beiting. I denne oppgaven er fem lokasjoner som er forskjellige i klima og vegetasjon prøvetatt. Alle disse lokalitetene beites i sommersesongen av ammekyr som er en del av den norske kjøttproduksjonen. Gjennom denne oppgaven ble det ikke beiting funnet til å signifikant påvirke det organiske karbonet i jorda (SOC-stock), konsentrasjonen av organisk karbon (SOC%) eller tykkelsen på det organiske sjiktet. I motsetning ble beiting funnet å signifikant redusere hot water extractable carbon (HWEC) signifikant i alle mineralsjikt og CN-forholdet (karbon:nitrogen) i det organiske sjiktet.M-MIN

Large mammalian herbivores and the paradox of soil carbon in grazing ecosystems: Role of microbial decomposers and their enzymes

Grazing is the dominant land use across the world, and large mammalian herbivores exert strong influence over biogeochemical cycles. Grazing ecosystems feature C-rich soils, even though herbivores consume a major fraction of plant production to reduce detrital input to soil. Yet, counter-intuitively, moderate grazing can promote net soil-C storage in many ecosystems compared to grazer-exclusion. We address this enigmatic influence of grazers on soil-C and test their indirect effect on proximate drivers of decomposition: microbial extracellular enzyme activity. We used a replicated long-term grazer-exclusion experiment to measure responses in above- and belowground plant biomass, soil-C stock, microbial biomass, labile/recalcitrant C pools and three enzymes relevant to the C-cycle: peroxidase—which initiates decomposition of recalcitrant matter, alongside beta-glucosidase and cellobiohydrolase—which act further downstream on more labile fractions. Consistent with other ecosystems, upto 12 years of herbivore exclusion did not increase soil-C in the fenced plots despite higher plant biomass and higher potential detrital C-inputs. Grazer-exclusion did not alter microbial biomass; peroxidase increased threefold and beta-glucosidase was doubled; cellobiohydrolase was unaffected. Grazer-exclusion also led to twofold increase in recalcitrant-C and in microbial respiration, but it did not influence labile-C. Structural equation models supported the hypothesis that grazing favours soil-C via its indirect effect on peroxidase, but they did not support that the effects can run in the opposite direction where soil-C affects enzymes. Grazer-mediated shifts in how microbes deploy enzymes emerge as a plausible mechanism that affects soil-C. These linkages may be important to maintain soil-C sequestration in drylands which support large mammalian herbivores

Glacier Monitoring Based on Multi-Spectral and Multi-Temporal Satellite Data: A Case Study for Classification with Respect to Different Snow and Ice Types

Remote sensing techniques are frequently applied for the surveying of remote areas, where the use of conventional surveying techniques remains difficult and impracticable. In this paper, we focus on one of the remote glacier areas, namely the Tyndall Glacier area in the Southern Patagonian Icefield in Chile. Based on optical remote sensing data in the form of multi-spectral Sentinel-2 imagery, we analyze the extent of different snow and ice classes on the surface of the glacier by means of pixel-wise classification. Our study comprises three main steps: (1) Labeled Sentinel-2 compliant data are obtained from theoretical spectral reflectance curves, as there are no training data available for the investigated area; (2) Four different classification approaches are used and compared in their ability to identify the defined five snow and ice types, thereof two unsupervised approaches (k-means clustering and rule-based classification via snow and ice indices) and two supervised approaches (Linear Discriminant Analysis and Random Forest classifier); (3) We first focus on the pixel-wise classification of Sentinel-2 imagery, and we then use the best-performing approach for a multi-temporal analysis of the Tyndall Glacier area. While the achieved classification results reveal that all of the used classification approaches are suitable for detecting different snow and ice classes on the glacier surface, the multi-temporal analysis clearly reveals the seasonal development of the glacier. The change of snow and ice types on the glacier surface is evident, especially between the end of ablation season (April) and the end of accumulation season (September) in Southern Chile

Nutrient availability controls the impact of mammalian herbivores on soil carbon and nitrogen pools in grasslands

Grasslands are subject to considerable alteration due to human activities globally, including widespread changes in populations and composition of large mammalian herbivores and elevated supply of nutrients. Grassland soils remain important reservoirs of carbon (C) and nitrogen (N). Herbivores may affect both C and N pools and these changes likely interact with increases in soil nutrient availability. Given the scale of grassland soil fluxes, such changes can have striking consequences for atmospheric C concentrations and the climate. Here, we use the Nutrient Network experiment to examine the responses of soil C and N pools to mammalian herbivore exclusion across 22 grasslands, under ambient and elevated nutrient availabilities (fertilized with NPK + micronutrients). We show that the impact of herbivore exclusion on soil C and N pools depends on fertilization. Under ambient nutrient conditions, we observed no effect of herbivore exclusion, but under elevated nutrient supply, pools are smaller upon herbivore exclusion. The highest mean soil C and N pools were found in grazed and fertilized plots. The decrease in soil C and N upon herbivore exclusion in combination with fertilization correlated with a decrease in aboveground plant biomass and microbial activity, indicating a reduced storage of organic matter and microbial residues as soil C and N. The response of soil C and N pools to herbivore exclusion was contingent on temperature – herbivores likely cause losses of C and N in colder sites and increases in warmer sites. Additionally, grasslands that contain mammalian herbivores have the potential to sequester more N under increased temperature variability and nutrient enrichment than ungrazed grasslands. Our study highlights the importance of conserving mammalian herbivore populations in grasslands worldwide. We need to incorporate local-scale herbivory, and its interaction with nutrient enrichment and climate, within global-scale models to better predict land–atmosphere interactions under future climate change.National Science Foundation Research Coordination Network, Long Term Ecological Research, Institute on the Environment, Strategic Resources of the Netherlands Institute of Ecology, Research Foundation Flanders, VENI grant, NWO-RUBICON grant, NWO-VENI grant, German Centre for Integrative Biodiversity Research, German Research Foundation (FZT 118).http://wileyonlinelibrary.com/journal/gcbpm2021Mammal Research InstituteZoology and Entomolog

Reconstruction of environmental and climate dynamics using multi-proxy evidence from palaeosols of the Western Cape, South Africa

Includes abstract.Includes bibliographical references.Like many of the world’s subtropical regions, the Western Cape of South Africa is highly sensitive to oscillations in the earth’s climate system triggered by major tectonic changes, local variations in orbital forcing, better known as Milankovitch cycles, and its position at the interface between temperate and tropical circulation systems. Regrettably, a dearth of reliable and continuous palaeoenvironmental records means that relatively little is known about how regional environments have been impacted over centennial to multi-millennial timescales. Palaeosols constitute an important stratigraphic marker for past environments and may provide useful validation of pedogenic and other earth system process models. However, the characterisation and analysis of palaeosols has been a largely neglected source of information in the Western Cape, South Africa. This thesis aims to improve the understanding of the environments and climate dynamics using evidences from palaeosols. Various palaeosol-based proxies including geochemistry, mineralogical, macro- and micromorphological, δ13C and δ18O isotope, and selected physico-chemical properties of palaeosols were studied and records obtained for four sites in the Western Cape. A number of chemical weathering indices and geochemical climofunctions were used to calculate weathering intensities, pedogenesis, palaeotemperature and palaeoprecipitation for the various locations using geochemical and stable isotope data. Results of this study indicate that palaeosol-based proxies have the potential to provide snapshots into the palaeoenvironments and palaeoclimate of Western Cape and may complement previous studies done with other proxies such as pollens and diatoms. For example, the interpretation of the pedofeatures (calcareousness, vertic, gleyic, illuviation) - from the micromorphology - of thepalaeosols suggests cyclic patterns of erosion and deposition that correlate with climate changes of the past. Podzolization and laterization are the principal pedogenic processes responsible for the red palaeosol formation at the Cape Peninsula, while calcification and salinization are accountable for the Quaternary palaeosols. Inferences of gleization and lessivage are only evident in the mid-Miocene palaeosol at Langebaanweg. At LBW, pedogenesis was more advanced in the Mid-Miocene and Early Pliocene layers signifying a more humid and warmer climate with more stable landscape. Two major regional climate cycles were evident at the Cape Peninsula: relatively warm and humid subtropical climate which gave rise to the pedogenically modified buried red palaeosol and dry semi-arid Mediterranean climate under which the soils overlying the stone line is currently forming, as seen from the poor horizonation and translocation of materials. Clay mineral assemblages suggest the Quaternary palaeoclimate of the Western Cape has been predominantly characterised by low precipitation and active coastal erosion, which jointly accounted for poor soil profile development. This is in agreement with the early reports obtained from marine records of the African continent (e.g. deMenocal, 2005). A cross plot of the δ13C and δ18O of the carbonate palaeosols indicates they all formed under strong marine influence and C3 plants have been dominant since late Quaternary

Management and display of four-dimensional environmental data sets using McIDAS

Over the past four years, great strides have been made in the areas of data management and display of 4-D meteorological data sets. A survey was conducted of available and planned 4-D meteorological data sources. The data types were evaluated for their impact on the data management and display system. The requirements were analyzed for data base management generated by the 4-D data display system. The suitability of the existing data base management procedures and file structure were evaluated in light of the new requirements. Where needed, new data base management tools and file procedures were designed and implemented. The quality of the basic 4-D data sets was assured. The interpolation and extrapolation techniques of the 4-D data were investigated. The 4-D data from various sources were combined to make a uniform and consistent data set for display purposes. Data display software was designed to create abstract line graphic 3-D displays. Realistic shaded 3-D displays were created. Animation routines for these displays were developed in order to produce a dynamic 4-D presentation. A prototype dynamic color stereo workstation was implemented. A computer functional design specification was produced based on interactive studies and user feedback