The Ecological Impacts of Mining at Seafloor Massive Sulfide Deposits on Megafaunal Assemblage Structure and Population Connectivity

<p>Deep-sea mining is rapidly becoming a reality, yet there are considerable gaps in our knowledge of the seabed assemblages that could be affected by mining activities. Seafloor Massive Sulfide (SMS) mining is expected to remove nearly all organisms in the immediate area and alter the remaining habitat, so that mitigation strategies for SMS mining will most likely need to include the establishment of protected areas to preserve the biodiversity that is lost at mine sites. Prospecting licences have been issued previously for SMS deposits within the New Zealand Exclusive Economic Zone (EEZ), however little is known about the seabed assemblages potentially at risk from SMS mining, particularly with respect to their structure (at multiple spatial scales) and the connectivity of assemblages at different sites. Designing studies to provide this information can be aided by turning to terrestrial, freshwater and shallow marine systems, where the fields of ecological theory, environmental management and conservation theory are better developed (Chapter 1). Prior to detailed investigations into the assemblage structure and population connectivity of New Zealand SMS deposits, it is essential to understand the global context of SMS mining. This was undertaken through an extensive literature review of SMS deposits, including their geology, seafloor communities, impacts from mining, international and national regulation, and environmental management (Chapter 2). In order to investigate the large-scale spatial distribution and structure of seafloor assemblages at SMS deposits, three New Zealand seamounts previously licenced for the prospecting phase of SMS mining were surveyed. Video footage from a towed camera was analysed to identify and characterise assemblages, and their association with environmental variation was investigated. Analysis of 249 video samples (each 250 m in length) distributed amongst the three seamounts indicated that SMS deposits support unique assemblages and that there were strong links between assemblage structure and environmental variation at a range of spatial scales. There was also a complex distribution of assemblages amongst the seamounts, suggesting a network of protected areas would be the most effective method for spatial management. Such networks should include sites that support the unique assemblages found in association with SMS deposits (Chapter 3). The fine-scale distribution and structure of assemblages at SMS deposits was investigated by using data from a single SMS deposit, Proteus 1, and comparing it to a Reference Site selected to have similar size and seabed characteristics to the deposit. Video footage from a Remotely Operated Vehicle (ROV) was used to identify and characterise assemblages, and their association with environmental conditions. Analysis of 153 video samples (each 15 m in length) confirmed the existence of assemblages unique to SMS deposits, and indicated that environmental characteristics specific to the deposit are responsible for the observed patterns of faunal distribution. Although five assemblages were shared between Proteus 1 and the Reference Site, six assemblages were unique to Proteus 1. This suggested that the proposed Reference Site would be inadequate on its own in terms of protecting the biological diversity present at the mine site but could contribute to a network of protected areas (Chapter 4). The issue of connectivity was addressed by examining the genetic connectivity of populations of the endemic hydrothermal vent mussel, Gigantidas gladius. Universal markers, archived material and off-the-shelf DNA extraction kits were used to investigate a cost effective approach. The assessment utilised variation in 586 base pairs of the mitochondrial cytochrome oxidase I subunit (COI) from 150 individuals in seven populations of G. gladius. Small sample sizes limited the recommendations that could be made for environmental management; however interpretation of the available sequences indicated panmixia with limited genetic structure and high connectivity amongst populations. Central Kermadec Volcanic Arc populations had particularly high haplotypic diversity and migrant exchange, suggesting they could be important for maintaining regional genetic connectivity and would merit inclusion in seabed protection measures (Chapter 5). Establishing protected areas for biodiversity needs to utilise all of the available information. The integrated findings of this thesis highlight the need for a network of protected seabed areas along the Kermadec Volcanic Arc to help mitigate the impacts of any future SMS mining activities. These networks should be highly connected (as determined by genetic connectivity) and include both active and inactive SMS areas to conserve 1) the endemic vent fauna in active areas and 2) the unique assemblages found in both environments (Chapter 6).</p>

The Ecological Impacts of Mining at Seafloor Massive Sulfide Deposits on Megafaunal Assemblage Structure and Population Connectivity

<p>Deep-sea mining is rapidly becoming a reality, yet there are considerable gaps in our knowledge of the seabed assemblages that could be affected by mining activities. Seafloor Massive Sulfide (SMS) mining is expected to remove nearly all organisms in the immediate area and alter the remaining habitat, so that mitigation strategies for SMS mining will most likely need to include the establishment of protected areas to preserve the biodiversity that is lost at mine sites. Prospecting licences have been issued previously for SMS deposits within the New Zealand Exclusive Economic Zone (EEZ), however little is known about the seabed assemblages potentially at risk from SMS mining, particularly with respect to their structure (at multiple spatial scales) and the connectivity of assemblages at different sites. Designing studies to provide this information can be aided by turning to terrestrial, freshwater and shallow marine systems, where the fields of ecological theory, environmental management and conservation theory are better developed (Chapter 1). Prior to detailed investigations into the assemblage structure and population connectivity of New Zealand SMS deposits, it is essential to understand the global context of SMS mining. This was undertaken through an extensive literature review of SMS deposits, including their geology, seafloor communities, impacts from mining, international and national regulation, and environmental management (Chapter 2). In order to investigate the large-scale spatial distribution and structure of seafloor assemblages at SMS deposits, three New Zealand seamounts previously licenced for the prospecting phase of SMS mining were surveyed. Video footage from a towed camera was analysed to identify and characterise assemblages, and their association with environmental variation was investigated. Analysis of 249 video samples (each 250 m in length) distributed amongst the three seamounts indicated that SMS deposits support unique assemblages and that there were strong links between assemblage structure and environmental variation at a range of spatial scales. There was also a complex distribution of assemblages amongst the seamounts, suggesting a network of protected areas would be the most effective method for spatial management. Such networks should include sites that support the unique assemblages found in association with SMS deposits (Chapter 3). The fine-scale distribution and structure of assemblages at SMS deposits was investigated by using data from a single SMS deposit, Proteus 1, and comparing it to a Reference Site selected to have similar size and seabed characteristics to the deposit. Video footage from a Remotely Operated Vehicle (ROV) was used to identify and characterise assemblages, and their association with environmental conditions. Analysis of 153 video samples (each 15 m in length) confirmed the existence of assemblages unique to SMS deposits, and indicated that environmental characteristics specific to the deposit are responsible for the observed patterns of faunal distribution. Although five assemblages were shared between Proteus 1 and the Reference Site, six assemblages were unique to Proteus 1. This suggested that the proposed Reference Site would be inadequate on its own in terms of protecting the biological diversity present at the mine site but could contribute to a network of protected areas (Chapter 4). The issue of connectivity was addressed by examining the genetic connectivity of populations of the endemic hydrothermal vent mussel, Gigantidas gladius. Universal markers, archived material and off-the-shelf DNA extraction kits were used to investigate a cost effective approach. The assessment utilised variation in 586 base pairs of the mitochondrial cytochrome oxidase I subunit (COI) from 150 individuals in seven populations of G. gladius. Small sample sizes limited the recommendations that could be made for environmental management; however interpretation of the available sequences indicated panmixia with limited genetic structure and high connectivity amongst populations. Central Kermadec Volcanic Arc populations had particularly high haplotypic diversity and migrant exchange, suggesting they could be important for maintaining regional genetic connectivity and would merit inclusion in seabed protection measures (Chapter 5). Establishing protected areas for biodiversity needs to utilise all of the available information. The integrated findings of this thesis highlight the need for a network of protected seabed areas along the Kermadec Volcanic Arc to help mitigate the impacts of any future SMS mining activities. These networks should be highly connected (as determined by genetic connectivity) and include both active and inactive SMS areas to conserve 1) the endemic vent fauna in active areas and 2) the unique assemblages found in both environments (Chapter 6).</p>

How Can Geomorphology Inform Ecological Restoration? A Synthesis of Geophysical and Biological Assessment to Determine Restoration Priorities

<p>The central concern that this study addresses is how an understanding of geomorphological processes and forms may inform ecological restoration; particularly practical restoration prioritisation. The setting is that of a hill country gully system covered in grazing pasture which historically would have been cloaked in indigenous forest. The study examines theory in conjunction with an application using a case study centred on Whareroa Farm (the restoration site) and Paraparaumu Scenic Reserve (the reference site) on the southern Kapiti Coast, north of Wellington. The impact that the change of land use has had on the soil and geomorphic condition of Whareroa and the influence the changes may have on the sites restoration is investigated. The thesis demonstrates a method of choosing reference sites to be used as templates for rehabilitating the restoration site. Geographical Information Systems and national databases are used and supplemented with site inspection. The reference site chosen, Paraparaumu Scenic Reserve, proved to be a good template for the restoration site particularly given that it is located in the midst of a heavily modified area. On-site inspection considering dendritic pattern and floristic composition confirms the database analysis results. Soil variables (bulk density, porosity, soil texture, pH, Olsen P, Anaerobic Mineralisable N, Total N (AMN), Total C and C:N ratio) are investigated and statistical comparisons made between the sites to quantify changes due to land-use change, i.e. deforestation and subsequent pastoral grazing. Factors investigated that may explain the variation in the soil variables were site (land use), hillslope location, slope aspect, and slope angle. Permutation tests were conducted to investigate the relationships between the independent factors and the SQI (dependent soil variables). Land use and slope angle were most frequent significant explanatory factors of variation, followed by hillslope location whilst slope aspect only influenced soil texture. A number of soil variables at Whareroa were found to be outside the expected range of values for an indigenous forest soil including AMN, Total N, Olsen P, and pH ...</p>

How Can Geomorphology Inform Ecological Restoration? A Synthesis of Geophysical and Biological Assessment to Determine Restoration Priorities

<p>The central concern that this study addresses is how an understanding of geomorphological processes and forms may inform ecological restoration; particularly practical restoration prioritisation. The setting is that of a hill country gully system covered in grazing pasture which historically would have been cloaked in indigenous forest. The study examines theory in conjunction with an application using a case study centred on Whareroa Farm (the restoration site) and Paraparaumu Scenic Reserve (the reference site) on the southern Kapiti Coast, north of Wellington. The impact that the change of land use has had on the soil and geomorphic condition of Whareroa and the influence the changes may have on the sites restoration is investigated. The thesis demonstrates a method of choosing reference sites to be used as templates for rehabilitating the restoration site. Geographical Information Systems and national databases are used and supplemented with site inspection. The reference site chosen, Paraparaumu Scenic Reserve, proved to be a good template for the restoration site particularly given that it is located in the midst of a heavily modified area. On-site inspection considering dendritic pattern and floristic composition confirms the database analysis results. Soil variables (bulk density, porosity, soil texture, pH, Olsen P, Anaerobic Mineralisable N, Total N (AMN), Total C and C:N ratio) are investigated and statistical comparisons made between the sites to quantify changes due to land-use change, i.e. deforestation and subsequent pastoral grazing. Factors investigated that may explain the variation in the soil variables were site (land use), hillslope location, slope aspect, and slope angle. Permutation tests were conducted to investigate the relationships between the independent factors and the SQI (dependent soil variables). Land use and slope angle were most frequent significant explanatory factors of variation, followed by hillslope location whilst slope aspect only influenced soil texture. A number of soil variables at Whareroa were found to be outside the expected range of values for an indigenous forest soil including AMN, Total N, Olsen P, and pH ...</p>

Archaeological and Chemical Investigation on Mortars and Bricks from a Necropolis in Braga, Northwest of Portugal

This investigation intends to study and characterize the mortars and bricks from walls and floors used in the funerary nucleus of the archaeological site of Dr. Gonçalo Sampaio Street (Braga, Portugal), associated with the Via XVII necropolis of the Bracara Augusta Roman city. The diversity of the funeral structures and their exceptional state of conservation make this sector of the necropolis an unprecedented case and a reference site in the archaeology of Braga, a determinant for its conservation and musealization. Nineteen mortars samples were analysed by X-ray Fluorescence. The results showed clear chemical composition differences among coating and floor mortars (CFM), masonry mortars (MM) and bricks (B) groups of samples. The chemical affinity between CFM from the V to IV centuries, CFM from the IV to V centuries, MM from brick walls (IV–V centuries), MM from stone walls (V–VII centuries) and B from the IV to V centuries samples were confirmed by statistical analyses. Their composition was distinctly related to the use of different raw materials, according to their chronological context; in mortars, according to their function in the structures; and in some samples, from contamination.

Spontaneous vegetation succession and recovery of ecosystem structure and function in a 40-year abandoned stone quarry in a Mexican tropical dryland

Background: The restoration of sites degraded by stone quarrying in drylands requires expensive interventions. However, these interventions cannot be used in tropical drylands because rural communities lack financial resources. Spontaneous vegetation succession may help restore degraded sites. However, spontaneous succession is evaluated by only comparing species composition between degraded and reference sites, without considering the structure and function of degraded sites. Question: Can spontaneous succession restore the structure and function of sites degraded by stone quarrying? Study sites and dates: San Rafael Coxcatlán, Puebla, 2013. Methods: We evaluated nine indicators of ecosystem structure and function in 4 degraded sites abandoned for 40 years and 1 reference site. Results: Spontaneous succession partially restored the structure and function of degraded sites. In all degraded sites, herb cover (20-49 %) and biocrust cover (21-51 %) were similar to those in reference site (19 %, 56 %). Three degraded sites also had canopy covers (57-76 %), shrub covers (51-52 %), and bare ground covers (2-3 %) similar to those in reference site (80 %, 42 %, 2 %). However, one degraded site displayed the opposite pattern (32 %, 8 %, 14 %). All degraded sites had lower tree cover (0-2 %), visual obstruction (6-25 %), and litter cover (3-30 %) than the reference site (21 %, 66 %, 77 %). Conclusions: Spontaneous succession helped restore the structure and function in some degraded sites.

Selection of an Appropriate Bedrock for Site Amplification Studies.

The selection of half-space or reference sites significantly influences site amplification studies. However, there are no well-defined guidelines in the literature. Generally, a layer with a local shear wave velocity (VS) of more than 760 m/s is considered a bedrock/half-space/reference site. This study attempts to formulate a rationale for selecting bedrock stiffness to be used as a half-space/reference site. For this study, VS,30 (average shear wave velocity of top 30-meter soil strata from shear wave velocity measurements) and the site's fundamental frequency (obtained from Horizontal to vertical spectral ratio of ambient vibration records) were used as proxies to study the influence of bedrock/half-space and development of a rationale for their selection. This study uses strong-motion data from India's sixty-two strong motion stations and a few from Japan (Kik-Net). The results suggest that considering a site with a shear wave velocity of 760 m/s may not be suitable as a half-space/bedrock for most geomorphological conditions. The results also recognize a pattern that can help in the development of a mathematical model for determining the bedrock for a site using VS,30 and its fundamental frequency as a proxy.

Agrivoltaic system impacts on microclimate and yield of different crops within an organic crop rotation in a temperate climate

Agrivoltaic (AV) systems integrate the production of agricultural crops and electric power on the same land area through the installation of solar panels several meters above the soil surface. It has been demonstrated that AV can increase land productivity and contribute to the expansion of renewable energy production. Its utilization is expected to affect crop production by altering microclimatic conditions but has so far hardly been investigated. The present study aimed to determine for the first time how changes in microclimatic conditions through AV affect selected agricultural crops within an organic crop rotation. For this purpose, an AV research plant was installed near Lake Constance in south-west Germany in 2016. A field experiment was established with four crops (celeriac, winter wheat, potato and grass-clover) cultivated both underneath the AV system and on an adjacent reference site without solar panels. Microclimatic parameters, crop development and harvestable yields were monitored in 2017 and 2018. Overall, an alteration in microclimatic conditions and crop production under AV was confirmed. Photosynthetic active radiation was on average reduced by about 30% under AV. During summertime, soil temperature was decreased under AV in both years. Furthermore, reduced soil moisture and air temperatures as well as an altered rain distribution have been found under AV. In both years, plant height of all crops was increased under AV. In 2017 and 2018, yield ranges of the crops cultivated under AV compared to the reference site were −19 to +3% for winter wheat, −20 to +11% for potato and −8 to −5% for grass-clover. In the hot, dry summer 2018, crop yields of winter wheat and potato were increased by AV by 2.7% and 11%, respectively. These findings show that yield reductions under AV are likely, but under hot and dry weather conditions, growing conditions can become favorable.

Empirical Spectral Amplification Function for a Reference Site Near Keddara Dam in Algeria using Strong Motion Data.

This paper deals with empirical spectral amplification function for a reference site (STK) near Keddara dam in Algeria using local strong ground motion of earthquakes of magnitudes Mw 4.0-6.8. Amplification function is obtained as the 5% damped mean spectral ratio of surface observed and the rock predicted ground motions and it is compared to the ambient vibration HVSR which shows a good agreement in terms of fundamental frequency and curve tendency. In addition, recorded ground motions are compared to surface predicted motion with modified GMPE, the site term of the local ground motion prediction equation is adjusted based on the obtained amplification function of the free field STK site. Examples of the M 6.8, M5.4 and M4.7 earthquakes show clearly the advantage of using the adjusted Ground Motion Prediction Equations (GMPE) for predicting surface ground motion. Site effect characterization and the adjusted GMPE presented in this study provide the basis elements toward partially non ergodic site specific-Probabilistic seismic hazard assessment (PSHA) application based on local strong motion data in Algeria.