9 2 Abstract The object of the study was the soil crust, found on spoil tips after coal mining near Sokolov. Certain type of crusts were compared; non-biological, physico-chemical origin and biological crusts that are made up of algae, mosses and lichens. Individual samples of the crusts underwent the laboratory analysis - Water Drop Penetration Time, Sequencing Electron Microscopy, water infiltration, and field studies, where the measurements were taken by using the erosion pins, the surface of the crusts was evaluated and photographed stereoscopically. The results indicate that the the physical-chemical type of crusts show significantly greater erosion, while the biological crusts are less susceptible to erosion, this phenomenon is probably related to the mechanical firming of the surface. Keywords: Soil crust, Mining soil, Mining, Infiltration, Erosion

abstract: Biological soil crusts (biocrusts) are topsoil communities of organisms that contribute to soil fertility and erosion resistance in drylands. Anthropogenic disturbances can quickly damage these communities and their natural recovery can take decades. With the development of accelerated restoration strategies in mind, I studied physiological mechanisms controlling the establishment of cyanobacteria in biocrusts, since these photoautotrophs are not just the biocrust pioneer organisms, but also largely responsible for improving key soil attributes such as physical stability, nutrient content, water retention and albedo. I started by determining the cyanobacterial community composition of a variety of biocrust types from deserts in the Southwestern US. I then isolated a large number of cyanobacterial strains from these locations, pedigreed them based on their 16SrRNA gene sequences, and selective representatives that matched the most abundant cyanobacterial field populations. I then developed methodologies for large-scale growth of the selected isolates to produce location-specific and genetically autochthonous inoculum for restoration. I also developed and tested viable methodologies to physiologically harden this inoculum and improve its survival under harsh field conditions. My tests proved that in most cases good viability of the inoculum could be attained under field-like conditions. In parallel, I used molecular ecology approaches to show that the biocrust pioneer, Microcoleus vaginatus, shapes its surrounding heterotrophic microbiome, enriching for a compositionally-differentiated “cyanosphere” that concentrates the nitrogen-fixing function. I proposed that a mutualism based on carbon for nitrogen exchange between M. vaginatus and its cyanosphere creates a consortium that constitutes the true pioneer community enabling the colonization of nitrogen-poor, bare soils. Using the right mixture of photosynthetic and diazotrophic cultures will thus likely help in soil restoration. Additionally, using physiological assays and molecular meta-analyses, I demonstrated that the largest contributors to N2-fixation in late successional biocrusts (three genera of heterocystous cyanobacteria) partition their niche along temperature gradients, and that this can explain their geographic patterns of dominance within biocrusts worldwide. This finding can improve restoration strategies by incorporating climate-matched physiological types in inoculum formulations. In all, this dissertation resulted in the establishment of a comprehensive "cyanobacterial biocrust nursery", that includes a culture collection containing 101 strains, isolation and cultivation methods, inoculum design strategies as well as field conditioning protocols. It constitutes a new interdisciplinary application of microbiology in restoration ecology. / Dissertation/Thesis / Doctoral Dissertation Liberal Studies 2019

Following a wildfire, land management agencies act quickly to protect ecosystem services. We don't currently understand how post-wildfire managers make trade-off decisions in these tight timelines, or if these decisions reflect current science. Using Brunson’s (2014) social-ecological systems multi-scalar model, surveys assessed manager opinions about post-wildfire projects, perceptions of stakeholder opinions, and ability or willingness to consider new science results. Public surveys asked local citizens their opinions about post-wildfire projects. Manager perceptions were measured through semi-structured phone interviews (n = 8) and a structured online survey (n = 256). Public surveys were mailed to 1,000 (971 deliverable, n = 152 usable) residents in rural and urban Great Basin and Mojave Desert ZIP codes. We found coarse- and fine-scale social and political opinions were associated with all post-wildfire management decisions, often creating perceived barriers to project implementation. Conversely, local citizens were more supportive of projects than managers perceived them to be. While the majority of managers and citizens supported the concept of incorporating experimental research, managers were less able to consider more specific research incorporation into actual projects. Ecologically, biological soil crusts (BSC) are emerging as an important fine-scale component of semi-arid restorations. However, even when BSCs are assessed prior to a restoration plan, it is unclear how or if this knowledge has any impact. BSCs were evaluated both socially and ecologically: all manager surveys contained questions specifically related to BSC, and a pilot greenhouse study assessed a) if seed drilling simulations on different stages of BSC may affect restoration plant establishment and b) if BSC excluded the invasive species Bromus tectorum. Similar to other new science results, managers were unlikely to be able/willing to consider BSC status in post-wildfire projects. However, our results suggest the possibility that, even when lightly burned, seeding strategy may influence native plant establishment. In ideal greenhouse conditions, B. tectorum was able to establish readily on both burned and unburned BSC.

The aim of the dissertation thesis is the assessment of the degradation of selected soil properties due to water erosion, including the temporal dynamics of these properties and the assessment of how this change affects the cumulative infiltration of the soil in watershed. Between 2012 and 2015, undisturbed and disturbed soil samples were collected on three experimental areas and the cumulative infiltration of the soil was measured. Experimental areas were selected on sloping, erosion-endangered blocks of arable land, in three cadastral territories of the Czech Republic, and this in the cadastral areas of Větřkovice, Čejkovice and Hustopeče. The cumulative infiltration was measured in three landscapes positions of the slope and soil samples were collected in three landscapes positions of the slope, at soil crust, topsoil and subsoil. In the Pedological Laboratory at the Institute of Landscape Water Management, Brno University of Technology, the particle density, bulk density, porosity, soil texture and water stable aggregates were determined from the samples taken. The cumulative infiltration of the soil was measured using the Double Ring Infiltrometer, the Mini Disc Infiltrometer and the mobile rainfall simulator. Using one-way analysis of variance to analyze the differences among soil samples and infiltration test. In addition, the dependence of soil crust formation, its physical properties and its influence on the cumulative infiltration of the soil were monitored on the areas.

No description available.

A geração de resíduos orgânicos juntamente com a erosão, são dois grandes problemas ambientais mundiais. São responsáveis pela redução da produtividade agrícola e pelos altos impactos ambientais. O presente projeto teve como objetivo a utilização de resíduos orgânicos gerados na agropecuária, na forma de composto orgânico, para a recuperação de áreas degradadas pela erosão hídrica. Foram avaliados os efeitos de quatro doses de composto (0, 20, 40 e 100 Mg.ha-1) na recuperação dos solos degradados por erosão. Somado a isto foi também avaliado o efeito da dose de composto sobre o processo de encrostamento superficial do solo. O projeto foi composto por dois experimentos, um com a ausência da erosão e o outro com presença de erosão (remoção de uma camada de 50 cm de solo), sendo realizados concomitantemente na mesma área. O delineamento experimental usado para cada experimento foi o inteiramente casualizado com 4 tratamentos (0, 20, 40 e 100 Mg.ha-1) e 4 repetições. Para o monitoramento da recuperação do solo e do processo de encrostamento em função das diferentes doses de composto, amostras deformadas e indeformadas de solo foram coletadas para análises físicas e químicas de rotina, para medidas da densidade do solo, para confecção de curvas características de retenção de água, e para análises micromorfológicas e de imagens. No campo foram realizados o monitoramento da chuva, da condutividade hidráulica e da infiltração de água no solo. Ficou claro que com o aumento da dose de composto orgânico aplicado no solo, melhor era a condição química do mesmo. Os valores dos elementos aumentavam conforme a dose de composto era também aumentada. A ação da matéria orgânica no solo colaborou com um aumento na retenção de água no solo a partir das doses de 40 e 100 Mg.ha-1. Esta melhor retenção de água favoreceu juntamente com a química, o crescimento das culturas no período seco garantindo assim uma maior produção de matéria seca das culturas implantadas, principalmente na dose de 100 Mg.ha-1. Com o aumento da porosidade do solo ao longo do tempo estudado em todas as doses de composto aplicado, a densidade do solo diminuiu onde o composto estava presente, se tornando mais constante em altas doses seus valores. A condutividade hidráulica do solo foi reduzida ao longo dos dois experimentos para todas as doses de composto aplicado. Essa redução pode ser explicada pelo aumento do encrostamento superficial do solo ao longo do tempo principalmente nas doses de 0 e 20 Mg.ha-1, dificultando a infiltração de água no solo. Portanto, a aplicação de altas doses de composto orgânico aceleram a recuperação dos atributos químicos e físicos do solo, assim como colaboram na redução da formação de vesículas nas crostas superficiais e diminuem os efeitos do impacto das gotas de chuvas na formação do encrostamento. / The generation of organic waste along with soil erosion are two major environmental problems worldwide. They are responsible for the reduction of agricultural productivity and high environmental impacts. The objective of this dissertation is the use of organic waste generated in agriculture, in the form of organic compost, for the recovery of degraded areas by water erosion. The effects of four doses of compost (0, 20, 40 and 100 Mg.ha-1) in the recovery of degraded soils by erosion, was tested. Added to this, the effect of the dose of compost on the process of soil surface crusting surface was also tested. The project was composed of two experiments, one with no erosion and the other with erosion (removal of a layer of 50 cm of soil), conducted concurrently in the same area. The experimental design for each experiment was completely randomized with 4 treatments (0, 20, 40 and 100 Mg.ha-1) and 4 replications. For the monitoring of the recovery of soil and the process of crusting according to the different doses of compost, deformed and undeformed soil samples were collected for routine physical and chemical analyses soil density evaluation, determination of the characteristic water retention curve, and for micromorphological and image analysis. In the field, rain, hydraulic conductivity and soil water infiltration were monitored. It was clear that with the increasing doses of organic compost used in the soil, the chemical condition meliorated. The content of the nutrients increased as the dose of compost was also increased. The action of organic matter in the soil collaborated with an increase in its water retention mainly for doses of 40 and 100 Mg.ha-1. This better water retention helped, together with the chemical recuperation, in the growth of the crops in the dry season thereby ensuring a higher dry matter yield, mainly in the dose of 100 Mg.ha-1. The increasing soil porosity over time observed in all doses of compost applied, led to a decrease in the soil density. The hydraulic conductivity of the soil was reduced in both experiments for all the applied compost doses. This reduction can be explained by the increase of the soil crusting process over time, especially in the doses of 0 and 20 Mg.ha-1, hampering the water infiltration in the soil. Therefore, the application of high doses of organic compost accelerates the recuperation of the chemical and physical attributes of the soil. It also collaborates in reducing the formation of vesicles in the superficial crust and decreases the effects of the impact of the raindrops on the crust formation.

A geração de resíduos orgânicos juntamente com a erosão, são dois grandes problemas ambientais mundiais. São responsáveis pela redução da produtividade agrícola e pelos altos impactos ambientais. O presente projeto teve como objetivo a utilização de resíduos orgânicos gerados na agropecuária, na forma de composto orgânico, para a recuperação de áreas degradadas pela erosão hídrica. Foram avaliados os efeitos de quatro doses de composto (0, 20, 40 e 100 Mg.ha-1) na recuperação dos solos degradados por erosão. Somado a isto foi também avaliado o efeito da dose de composto sobre o processo de encrostamento superficial do solo. O projeto foi composto por dois experimentos, um com a ausência da erosão e o outro com presença de erosão (remoção de uma camada de 50 cm de solo), sendo realizados concomitantemente na mesma área. O delineamento experimental usado para cada experimento foi o inteiramente casualizado com 4 tratamentos (0, 20, 40 e 100 Mg.ha-1) e 4 repetições. Para o monitoramento da recuperação do solo e do processo de encrostamento em função das diferentes doses de composto, amostras deformadas e indeformadas de solo foram coletadas para análises físicas e químicas de rotina, para medidas da densidade do solo, para confecção de curvas características de retenção de água, e para análises micromorfológicas e de imagens. No campo foram realizados o monitoramento da chuva, da condutividade hidráulica e da infiltração de água no solo. Ficou claro que com o aumento da dose de composto orgânico aplicado no solo, melhor era a condição química do mesmo. Os valores dos elementos aumentavam conforme a dose de composto era também aumentada. A ação da matéria orgânica no solo colaborou com um aumento na retenção de água no solo a partir das doses de 40 e 100 Mg.ha-1. Esta melhor retenção de água favoreceu juntamente com a química, o crescimento das culturas no período seco garantindo assim uma maior produção de matéria seca das culturas implantadas, principalmente na dose de 100 Mg.ha-1. Com o aumento da porosidade do solo ao longo do tempo estudado em todas as doses de composto aplicado, a densidade do solo diminuiu onde o composto estava presente, se tornando mais constante em altas doses seus valores. A condutividade hidráulica do solo foi reduzida ao longo dos dois experimentos para todas as doses de composto aplicado. Essa redução pode ser explicada pelo aumento do encrostamento superficial do solo ao longo do tempo principalmente nas doses de 0 e 20 Mg.ha-1, dificultando a infiltração de água no solo. Portanto, a aplicação de altas doses de composto orgânico aceleram a recuperação dos atributos químicos e físicos do solo, assim como colaboram na redução da formação de vesículas nas crostas superficiais e diminuem os efeitos do impacto das gotas de chuvas na formação do encrostamento. / The generation of organic waste along with soil erosion are two major environmental problems worldwide. They are responsible for the reduction of agricultural productivity and high environmental impacts. The objective of this dissertation is the use of organic waste generated in agriculture, in the form of organic compost, for the recovery of degraded areas by water erosion. The effects of four doses of compost (0, 20, 40 and 100 Mg.ha-1) in the recovery of degraded soils by erosion, was tested. Added to this, the effect of the dose of compost on the process of soil surface crusting surface was also tested. The project was composed of two experiments, one with no erosion and the other with erosion (removal of a layer of 50 cm of soil), conducted concurrently in the same area. The experimental design for each experiment was completely randomized with 4 treatments (0, 20, 40 and 100 Mg.ha-1) and 4 replications. For the monitoring of the recovery of soil and the process of crusting according to the different doses of compost, deformed and undeformed soil samples were collected for routine physical and chemical analyses soil density evaluation, determination of the characteristic water retention curve, and for micromorphological and image analysis. In the field, rain, hydraulic conductivity and soil water infiltration were monitored. It was clear that with the increasing doses of organic compost used in the soil, the chemical condition meliorated. The content of the nutrients increased as the dose of compost was also increased. The action of organic matter in the soil collaborated with an increase in its water retention mainly for doses of 40 and 100 Mg.ha-1. This better water retention helped, together with the chemical recuperation, in the growth of the crops in the dry season thereby ensuring a higher dry matter yield, mainly in the dose of 100 Mg.ha-1. The increasing soil porosity over time observed in all doses of compost applied, led to a decrease in the soil density. The hydraulic conductivity of the soil was reduced in both experiments for all the applied compost doses. This reduction can be explained by the increase of the soil crusting process over time, especially in the doses of 0 and 20 Mg.ha-1, hampering the water infiltration in the soil. Therefore, the application of high doses of organic compost accelerates the recuperation of the chemical and physical attributes of the soil. It also collaborates in reducing the formation of vesicles in the superficial crust and decreases the effects of the impact of the raindrops on the crust formation.

The investigation was designed to explore the structure, composition and activity of a biological soil crust on an acidic, sandy soil from a temperate climate. The crust covers several hundreds of square meters on the hilltop of a large terminal moraine. The conjugate alga <i>Zygogonium ericetorum</i> forms the essential matrix for the crust, a dense web of algal filaments with interspersed lichens and mosses. The crust is composed of three layers, with an uppermost layer consisting nearly entirely of a dense algal mat. In lower layers, a parasitic fungus, penetrating the algal cells, is another important component of the crust community. In this soil crust, photosynthetic and respiratory activity is stabilized at low water activities.

In arid and semi-arid deserts, soils are commonly covered with biological soil crusts. The study of arid biocrusts and their ecological function has become increasingly common in the literature over the last several decades. Interestingly, no mention is made of biological soil crusts in forested ecosystems, raising the question as to whether they exist in these areas and if they do, why they have yet to be recognized as such? Through the use a parallel logic, this study finds that biocrusts do indeed exist in forests, a novel relationship in forest ecology and seeks to determine if there exist ecophysical explanations for the abundance and distribution throughout the forest landscape. This study examined the effects of climate variables and substrate types on the abundance, distribution and overall cover of forest soil biocrust at fifty-two sites in southern Oregon, U.S.A. Sites were randomly selected within established buffer zones in the Siuslaw, Rogue-Sisikyou, Umpqua, and Fremont-Winema National Forests. The methods of Belnap et al 2001 were tested and then modified for application in forested ecosystems. Data were collected on the relative abundance and distribution of biocrust morphological groups across available substrates, community biocrust morphology, aspect, elevation and soil texture, pH and organic matter content. Site-specific data on average annual precipitation and minimum/maximum temperatures was collected using the PRISM Climate Model. This study found substrate colonization by specific morphological groups mixed across the study; though dominant communities were observed for each substrate present, substrate availability appears to be confounded by a number of variables (climate, stand age and structure and litter layer) not controlled for in this study. Biocrust community morphologies varied across sites, primarily influenced by the surface texture of the substrate and morphology of the individual. Relatively smooth surfaces (rock, bare soil) often resulted in smooth biocrust morphologies, whereas rough surfaces (dead wood, bare soil) tended to result in a rolling morphology. Litter layer directly influenced the relative proportion of substrates colonized, notably affecting dead wood and mineral soil biocrusts. Total biocrust cover increased as precipitation increased as did biocrust preference for dead wood substrates while mineral soil remained unchanged and rock surfaces were negatively represented. Aspect generally followed the anticipated distribution of total biocrust cover with the highest cover on N and NW aspects and lowest on the W aspect. Increases in elevation were negatively related to overall biocrust cover. Soil texture was not found to be directly related to overall biocrust cover, attributed in part to the highly adaptive nature of the biocrust community. Soil organic matter (SOM) influenced total biocrust cover with positive correlations between total cover and increasing SOM content. Soil pH increased as expected across the precipitation range (17 to 159 in/yr) of the transect. Total biocrust cover was found to trend with soil pH, but is believed to be attributed to the parallel relationship between precipitation and pH, rather than pH alone given the relative moderate pH range (4.39 to 6.54) of the study. The distribution and abundance of forest soil biocrusts is strongly influenced by precipitation. The confounding influence of precipitation to litter layer depth and organic matter content (through gradients of vegetative productivity) and soil pH further are concluded to influence substrate preference by morphological groups. Across the variables examined, similarities between the two communities (arid and forest) in response to climate and soil chemistry show parallel relations, justifying the formal establishment of biological soil crust community in forested regions. The differences between communities related to the presence of trees validate the establishment of forest soil biocrusts as distinct community in both form and ecological function with the forests. / Graduation date: 2013