Southern Interior Research Articles

Holocene biogeography of the southwestern European white‐toothed shrew (Crocidura iculisma, Eulipotyphla) through its fossil record

Abstract Crocidura iculisma (=C. suaveolens) is a shrew (Soricidae, Eulipotyphla) showing a fragmented distribution limited to the Iberian Peninsula, southern and western France and northwestern Italy. Although it has been in the Iberian Peninsula since the Middle Pleistocene, its biogeographical history remains poorly known. Here, we provide new data on Crocidura iculisma from the Castillejo del Bonete site (southern Spain) dated as 3.8–3.6 cal kyr BP. At the same time, we analyse changes in its geographic distribution based on its palaeontological record. We have reviewed thoroughly the Holocene record of Crocidura iculisma in southwestern Europe, considering independently the three time intervals according to the stages defined for this geological time series (Greenlandian, Northgrippian and Meghalayan). Whenever found together in fossil sites, the relative abundance of the two sympatric shrews of the genus Crocidura (Crocidura russula and Crocidura iculisma) was analysed. The data obtained concerning past distribution range and relative abundance were compared with the current status of the species in Iberia to interpret changes through time. The distribution range of the southwestern European white‐toothed shrew in the Iberian Peninsula has notably reduced over time until today. The occurrence at Castillejo del Bonete and other palaeontological records located beyond its current distribution range show that it was distributed in several areas of the eastern part and southern interior of Iberia, at least until the second half of the Meghalayan. Relative abundance patterns observed in the fossil assemblages suggest that competitive exclusion by Crocidura russula and climatic changes played a crucial role in driving the extirpation of Crocidura iculisma from a substantial portion of the Iberian Peninsula.

Climate change and drinking water: exploring resilience to wildfire in the BC Southern Interior

Climate change and drinking water: exploring resilience to wildfire in the BC Southern Interior

Role of Japan Sea Throughflow in the spatial variability of the long-term sea surface temperature trend

The Japan Sea shows a much stronger warming of long-term sea surface temperature (SST) than surrounding oceans. The warming trend possesses a meridionally alternating zonal band pattern, with weak trends along the paths of the Japan Sea Throughflow and strong trends in the remaining interior region. Using idealized models of the Japan Sea Throughflow and atmospheric heating, this study examines the process behind the formation of such spatial patterns in the SST trend. We find that zonal band structures form in a flat rectangular coastline model, and heat budget analysis shows that horizontal heat transport, due to throughflow, reduces the warming effect created by the surface heat flux. A weak SST trend appears around the jet, while a strong SST trend appears elsewhere. Bathymetric effects are also examined using a model with realistic coastline settings. The location of the western boundary current stabilizes, and the coastal branch begins to disconnect from the Japanese coastline toward the north, allowing a more stable SST warming region to form in the southern interior region. Lagrangian particle tracking experiments confirm that a weak (strong) SST trend corresponds to a short (long) residence time, and eddies in the Japan Sea prolong the residence time in interior regions. The model results suggest that the accumulation time of surface heating is essential to the spatial distribution of the long-term SST warming trend.

Atmospheric Moon River

These two long poems address both embodied and encultured experiences of climate change in the Kelowna region of the Okanagan Valley and the Salmon Arm region of the Shuswap in the British Columbia southern interior. Both poems grapple with the fear of future-oriented thinking in a time of climate catastrophe while registering the long historical dimensions that inform that present fear.
 “Atmospheric Moon River” examines desire and beauty in the context of torrential rain and flooding that resulted in the deaths of several humans and many hundreds of farm animals. The poem updates old questions about the ethics of aesthetics when it comes to suffering in the present environmental context. The poem also draws a line from the first erotic love poem in English to the work of cultural theorists such as Michel Foucault and Judith Butler and “classic” Hollywood cinema. 
 “Sweet Air” links a story of personal illness and the loss of reproductive potential to the drama and climate anxiety of dramatically unseasonable weather. In “Sweet Air” the interlocutor of the poem has portions of her fallopian tubes removed to protect her from future illness resulting in the loss of an imagined future. That loss plays out against the backdrop of climate uncertainty and the resulting troubling of broader imagined futures. 

Adding scent: exploring improvements in pan trapping to monitor pollinators

Our project assessed whether adding floral scents to pan traps would increase the abundance and/or diversity of Hymenoptera sampled or decrease bycatch. We sampled insects using white pan traps containing 0.5 mL of floral scent (linalool, phenylacetaldehyde, limonene, geraniol, benzaldehyde, no scent control) per liter of trapping solution in an interior southern California natural space. Scented traps shared between 53.0% and 79.7% similarity in Hymenoptera assemblage and 59.5% and 72.2% similarity when using presence/absence data as compared with the control. Phenylacetaldehyde and geraniol increased the capture rate of new Hymenoptera, while phenylacetaldehyde also increased overall Hymenoptera and bycatch capture rate. Additionally, we noted that phenylacetaldehyde traps increased small parasitoid wasp capture 10-fold, potentially indicating an alternative use for the addition of phenylacetaldehyde to pan traps. We found no evidence that the addition of scent decreased the abundance or diversity of Hymenoptera caught. Those seeking to exhaustively record the species richness in an area may benefit the most from this method with potential to increase capture of large-bodied, rare, or specialist pollinating Hymenoptera with scent preference, though further research is needed. Based on the data presented here, scent should be explored further for its effect on pan trap catch.

Addressing the Spatiotemporal Patterns of Heatwaves in Portugal with a Validated ERA5-Land Dataset (1980–2021)

This study presents a comprehensive analysis of heatwaves in mainland Portugal from 1 October 1980 to 30 September 2021 (41 hydrological years). It addresses a research gap by providing an updated assessment using high-resolution reanalysis daily minimum and maximum temperature data (Tmin and Tmax) from the gridded ERA5-Land dataset, overcoming the lack of publicly available daily temperature records. To assess the representation of the previous dataset, nine different grid-point locations across the country were considered. By comparing monthly ERA5-Land temperature data to ground-based records from the Portuguese Met Office, a monthly validation of the data was conducted for the longest common period, demonstrating good agreement between the two datasets. The heatwave magnitude index (HWMI) was employed to establish the temperature thresholds and thus identify heatwaves (defined as three or more consecutive days above the threshold). With over 640 Tmin heatwave days recorded at each of the nine ERA5-Land grid-points, data analysis revealed a discernible upward trend in Tmin heatwaves. The grid-point situated in the capital city’s urban area, i.e., Lisbon, exhibited the highest number of Tmin heatwave days. With an average of more than 800 Tmax heatwave days over the 41-year period, the northern and interior regions of Portugal had the greatest number of occurrences, reaching up to 916. A kernel rate estimation method was applied to further investigate the annual frequency of Tmin and Tmax heatwave occurrences. Results exhibited clear temperature changes, with a widespread increase in the number of heatwave days over the past two decades, particularly for Tmax. In summary, the occurrence of this phenomenon displayed significant spatial variations, with the southern interior and coastal grid-points experiencing a greater increase in annual Tmax heatwave days, rising from 10 to 30 between 2018 and 2019.

Predicting favourable streams for anadromous salmon spawning and natal rearing under climate change

Successful management of imperilled anadromous salmon stocks requires understanding how salmon will respond to a changing climate across their extensive ranges. Though largely unused for anadromous salmon to date, environmental niche models (ENMs) can provide a strong foundation for estimating where and how much habitat will likely remain favourable. We applied a comprehensive suite of ENM statistical approaches to five Pacific salmon species, focusing on freshwater spawning and natal rearing habitat as not only critical for population survival, but also highly susceptible to a changing climate. We developed ENMs for spawning ranges across British Columbia (BC), Canada, and western US, and projected future scenarios for BC. Projections indicated net expansion of favourable spawning habitat across species in BC, with the most change occurring by 2060. However, shifts in favourable habitat varied greatly geographically and by species, with notable reductions in coastal and southern interior streams. Our results provide a basis for identifying important changes in spawning and natal rearing habitat conditions to help inform priorities for restoration and protection actions.

Fire-killed forest biomass for mills and communities and bioenergy GHG impacts

We examine the supply chains of post-fire salvage harvest to 28 mills or 10 communities in British Columbia, Canada, and assess the net change in GHG emissions for community bioenergy and biofuels, relative to a ‘do-nothing’ baseline with fossil fuel use.Lowest-cost supply chains for post-fire salvage had largest hauled biomass for mills in the southern interior of the province, with mills in close proximity to each other having small fibresheds and low haul costs. Supply chains were also quantified for salvage biomass hauled to communities by using a lowest GHG optimization routine that selected between liquid transportation fuels or community bioenergy (heat and/or electricity). For the first few decades, avoided GHG emissions were larger when biomass was used for bioenergy (heat and/or electricity), mainly in larger communities, to avoid fossil fuel burning. As energy systems decarbonized, biomass was used for biofuels, and production was more evenly distributed amongst the communities.Adding these results to an integrated framework with previously published ecosystem emissions and removals assessed the net change in GHG emissions for a post-fire rehabilitation and bioenergy scenario relative to a ‘do-nothing’ baseline with continued fossil fuel use. We found that there was an initial increase in net GHG emissions even though biogenic emissions from bioenergy were partially offset by avoided fossil fuel emissions. Over time, an enhanced sink from rehabilitation activities combined with avoided fossil fuel emissions resulted in a cumulative (2020–2070) GHG reduction at median levels of −6 TgCO2e with a range from reduced emissions of −39 TgCO2e to increased emissions 37 TgCO2e. Cumulative avoided fossil emissions were −62 TgCO2e with a range from −49 TgCO2e to −86 TgCO2e.

Regional vulnerability to environmental and climate change risks: A study of Odisha, India

Climate change-induced risks and their regional implications are inevitable on land, resources, and living communities. It is a social challenge because societies are at risk at varied levels. To study the relationship between regional vulnerability to climate change risks is to give a telescopic view from below. The state of Odisha, located along the eastern coastal region of India, is selected for the present study. Considering natural, demographic, and economic aspects, selected indicators at the district level are applied in the study. In the context of the functional relation to climate change risk, the indicator score is standardized, the vulnerability index calculated, and districts are categorized based on the vulnerability scale. The analysis shows remarkable spatial variations in higher and lower vulnerability districts in the state. These spatial contrasts are associated with the development pattern of the state. Most vulnerable are in the western and southern interior and a few in the north compared to the low vulnerability districts located along the eastern coast and central part of the state. The regional vulnerability perspective thus offers insights and contributes towards strengthening development strategy, responses, and policymaking for tackling climate change risks and the implications and concerns across the region.

Compositional characterization of pottery and clays from Guam by NAA

Neutron activation analysis (NAA) was performed on a sample of 38 pottery sherds and five clays recovered from archaeological sites and river valleys in Guam. To maximize the chance of finding compositional differences, sherds were sampled from sites in five different coastal areas and nine sites in the island’s southern interior. The clays came from two locations in the island’s southern interior. The analytical and statistical procedures used to identify two subgroups within the pottery samples are described and a relationship between one of the subgroups and the clays is discussed.

Rainfall Interception by Mature Coastal and Interior Forests in British Columbia

Interception of rainfall by forest canopies and its evaporation back to the atmosphere is an important component of the hydrological balance. We quantify the influence of six mature forests at two coastal and one southern interior locations in British Columbia on interception loss. Drainage from the canopy was measured with throughfall troughs and stemflow collars that emptied into tipping buckets monitored by data loggers. Interception loss was evaluated on an event basis and summed to monthly and seasonal totals. The throughfall coefficients increased with a decrease in canopy volume with values of 0.3 for the south coast forest, 0.5 for the north coast forests, and 0.6 for the southern interior forests. The respective saturation capacities were 2.0, 1.1, and 0.6 mm. The average evaporation rates during events varied from 0.05 to 0.3 mm h-1 at all sites. Consequently, for large events, interception loss was dominated by evaporation and replenishment of water in storage during the event. Increasingn event size increased interception loss, which tended to plateau at large events. The coastal forests had throughfall 75±2 percent, stemflow 1±0.2 percent, and interception loss 24±2 percent of the May to November rainfall. The respective values for the interior forests were 72±3 percent, 0.05±0.05 percent, and 28±3 percent of the late May to October rainfall. The similarity between coastal and interior sites in the partitioning of the seasonal rainfall resulted from the differing distributions of event size and similar evaporation rates of intercepted water during events.

Climatology and Composite Evolution of Flash Drought over Australia and Its Vegetation Impacts

Abstract This study describes flash drought (FD) inferred from the evaporative stress index (ESI) over Australia and its relationship to vegetation. During 1975–2020, FD occurrence ranges from less than 1 per decade in the central arid regions to 10 per decade toward the coasts. Although FD can occur in any season, its occurrence is more frequent in summer in the north, winter in the southern interior and southwest, and across a range of months in the far southeast and Tasmania. With a view toward real-time monitoring, FD “declaration” is defined as the date when the ESI declines to at least −1, i.e., drought conditions, after at least 2 weeks of rapid decline. Composite analysis shows that evaporative demand begins to increase about 5–6 weeks before declaration with an increase in solar radiation, while evapotranspiration initially increases with evaporative demand but then decreases in response to the soil moisture depletion. Solar radiation increases simultaneously with precipitation deficit, both reaching their peak around declaration. FD intensity peaks with soil moisture depletion, 2–3 weeks after declaration. The composite wind speed only shows a modest increase around declaration. The composite FD ends 4 weeks after rapid decreases in solar radiation and increases in precipitation. Satellite-derived vegetation health composites show pronounced decline in the nonforested regions, peaking about 4–8 weeks after FD declaration, followed by a recovery period lasting about 12 weeks after flash drought ends. The forest-dominated regions, however, are little impacted. Modeled pasture growth data show reduced values for up to 3 months after the declaration month covering the main agricultural areas of Australia. Significance Statement Flash drought describes a fast intensification or rapid development of drought conditions with potential severe impacts on agriculture and ecosystems. This study describes the climatology and typical evolution of flash drought over Australia for the period 1975–2020. An objective definition of flash drought, using high-resolution observational-based datasets, is proposed and its spatiotemporal variability is provided, as well as its relationship with vegetation health and pasture growth. This constitutes a guideline for understanding flash drought in Australia and its impacts on vegetation.

Smallholder farmers’ knowledge, practices and perceptions associated with grain storage and hermetic technology in southern Ghana: Implications for awareness and training

Hermetic grain storage (HGS) bags are simple and appropriate to effectively protect stored grains against pests and aflatoxins in areas where effective facilities are lacking. This study assessed farmers’ knowledge and perceptions associated with current practices, awareness-facilitating agents, and HGS bags in interior southern Ghana. The main objective was to provide information that can be included in sensitization and awareness creation programs to increase adoption of HGS bags for sustainable production of grain crops, food security, income-generation, and livelihood improvement across farming communities in selected areas in southern Ghana. Therefore, 925 smallholder farmers were randomly selected and interviewed across three districts (or municipals), which included West Akim Municipal, Ayensuano District, and Suhum Municipal in southern Ghana, using a semi-structured questionnaire for data collection and analysis. The results showed that 95.24% of farmers were still using ineffective grain storage approaches to store grains. Average awareness level about HGS bags among farmers was ≤30%, whereas adoption of HGS bags was very low (4.76%). However, awareness and adoption were mostly observed in West Akim Municipal. Although awareness was significantly dependent on numerous demographic and farming factors, it had significant positive correlations with ‘female farmers’ and respondents’ age-range (36–50 years) only; it suggests that if these two factors are considered in sensitization programs, they will increase awareness about HGS bags. The most performing awareness-facilitating agent was the Ministry of Food and Agriculture, followed by famers’ neighbors. Nonetheless, farmers (who were aware of or adopted HGS bags) were facing challenges or limitations. Hence, the need for training smallholder farmers has been discussed.

Indigenous Organizations Increasingly Being Funded by B.C. Corporation

Laurel Douglas has certainly proven to be a changemaker. Douglas was brought on board as the CEO of ETSI-BC in May 2020. The full name for the British Columbia-based not-forprofit corporation is the Economic Trust of the Southern Interior. ETSI-BC, previously known as the Southern Interior Development Initiative Trust, was launched in 2006 by the B.C. government to administer a $50 million endowment fund that was intended to support economic investment in the southern interior of the province. Governance of the trust is carried out by the 13 individuals who serve on ETSI-BC’s board of directors. Five of the board members are appointed by the province. The other eight are district representatives within ETSI-BC’s coverage area.

Winner and losers: examining biotic interactions in forbs and grasses in response to changes in water and temperature in a semi-arid grassland.

Warming and changing water amount can alter the outcome of biotic interactions in native and exotic plants between facilitation and competition. Exotic plants may adapt better to changing environmental conditions, such that they may compete better than native plants. We conducted competition trials for four plant species, two exotic forbs (Centaurea stoebe and Linaria vulgaris) and two grasses (exotic Poa compressa and native Pseudoroegneria spicata), commonly found in Southern interior British Columbia. We compared the effects of warming and changing water on target plant shoot and root biomass, and on pair-wise competitive interactions among all four species. We quantified interactions using the Relative Interaction Intensity index, which has values from -1 (complete competition) to +1 (complete facilitation). C. stoebe biomass was highest under low water and no competition. Facilitation of C. stoebe was found under high water and low temperatures but shifted to competition under low water and/or warming. Competition in L. vulgaris decreased due to reduced water and increased due to warming. Grasses were less competitively suppressed by warming but more competitively suppressed by reduced water input. The response of exotic plants to climate change can differ by plant species, moving in opposite directions for both forbs, but grasses appear to respond similarly. This has consequences for grasses and exotic plants in semi-arid grasslands.

Roles of Surface Forcing in the Southern Ocean Temperature and Salinity Changes under Increasing CO2: Perspectives from Model Perturbation Experiments and a Theoretical Framework

Abstract A rapid warming and freshening of the Southern Ocean have been observed over the past several decades and are attributed to anthropogenic climate change. In this study, ocean model perturbation experiments are conducted to separate roles of individual surface forcing in the Southern Ocean temperature and salinity changes. Model-based findings are compared with results from a theoretical framework including three idealized processes defined on the θ–S diagram. Under the future scenario of CO2 doubling, the heat flux forcing dominates the large-scale warming, deepening of isopycnals, and spiciness changes along isopycnals, which can be captured by an idealized pure warming process to represent the subduction of surface heat uptake. The poleward-intensifying westerly winds account for 24% of the enhanced warming between 35° and 50°S and would have comparable contribution as the heat flux forcing after removing the global ocean warming effect. In contrast, the widespread freshening in the Southern Ocean driven by increased surface freshwater input is largely compensated by the wind-driven saltening. The response to freshwater forcing could not be approximated as a similar pure freshening process as the induced cooling and freshening have comparable effects on density. The wind-driven changes are primarily through the local heave of isopycnals, thus resembling an idealized pure heave process, but contain considerable spiciness signals especially in the midlatitude Southern Ocean, resulting from anomalous northward transport and subduction of heat and salt that are largely density-compensating. These distinct signatures of individual surface forcing help us to better understand observed and projected changes in the Southern Ocean. Significance Statement Considerable changes including a rapid warming and freshening have been observed in the Southern Ocean as it absorbs most of the extra heat from the anthropogenic climate change, receives increased surface freshwater input, and experiences a poleward shift and intensification of the westerly winds. The purpose of this study is to distinguish different contributions from surface heat flux, freshwater flux, and wind forcing to the Southern Ocean temperature and salinity changes, based on ocean model experiments and three idealized processes from a theoretical framework. Our study reveals distinct signatures of individual surface forcing that help us to understand linkages between changes seen at the surface and in the interior Southern Ocean.

Mallard (<i>Anas platyrhynchos</i>) drake observed consuming an adult Western Tiger Salamander (<i>Ambystoma mavortium</i>)

We observed a Mallard (Anas platyrhynchos) drake consuming an adult Western Tiger Salamander (Ambystoma mavortium) in the southern interior of British Columbia, Canada. To our knowledge, this is the first published report of this predator–prey interaction. We outline the events of the short observation, briefly discuss natural history of the predator and prey relevant to the observed interaction, and provide chronological photographs of the event.

The importance of effective moisture and landscape controls on diatom assemblages and primary production in Roche Lake, British Columbia, Canada over the past ca. 1800 years

AbstractLakes in the semiarid Southern Interior Plateau of British Columbia, Canada are vulnerable to future climate-driven changes in water quantity and quality. However, few long-term monitoring records exist to assess the effects of varying hydroclimate conditions on lake function. We present a high-resolution multiproxy paleolimnological record containing subfossil diatoms, μXRF via ITRAX, and chlorophyll-athat spans the past 1800 years from Roche Lake in south-central British Columbia. Generalized additive models indicate that the diatom assemblages were associated with changes in lake level and the accompanying effects of atmospheric forcing on lake thermal structure, and that these forcing mechanisms had a weak relationship with primary production. We infer two pronounced arid periods between ca. AD 600–950 and ca. AD 1730–1950 that correspond to evidence of reduced lake mixing and enhanced anoxia, but variable patterns in primary production. Synthesis of regional proxy records suggests that inferences of moist but possibly warm conditions during the Medieval Climate Anomaly may have occurred because of a complex interaction between prolonged La Niña-like conditions and higher radiative forcing. Overall, lakes in this region are sensitive to changes in hydroclimate generated by interactions between external forcing and Pacific Ocean–atmosphere processes, and the resulting changes in aridity may have potentially negative consequences on salmonid habitat.

Paedomorphic Blotched Tiger Salamander (<i>Ambystoma mavortium melanostictum</i>) in ovo counts, British Columbia, Canada

Reproductively mature larval morphs, known as paedogens, are a rare occurrence in Blotched Tiger Salamander (Ambystoma mavortium melanostictum). The Southern Mountain population of this subspecies, confined to the southern interior of British Columbia, is listed federally as Endangered and has been facing increasing pressures from anthropogenic stressors in both their aquatic and terrestrial landscapes. In 2017, we examined a subset of 36 frozen Blotched Tiger Salamander paedogens collected in September 1985 after rotenone treatment in preparation for a recreational fishery near Oliver, British Columbia. We estimated total in ovo numbers in nine gravid individuals to gain insight into paedogen reproductive condition. The number of eggs per individual averaged 227 ± 109 [SD]; range 28–421), with larger dark eggs accounting for 133 ± 69 and smaller pale eggs (possibly follicles or colour may be an artifact of storage) accounting for 94 ± 49. Salamanders were collected in September after the expected egg-laying period for the terrestrial form (early spring); thus, the reproductive stage of the eggs is unclear, but is assumed to be post-breeding and representative of developing eggs and follicles. Canadian data on in ovo counts within the body cavity have not been reported for Blotched Tiger Salamander paedogens and our study provides valuable information on the reproductive condition of paedogens. Although terrestrial forms have been observed, the presence of paedogens in the treated wetland has yet to be detected.

Development and implementation of a Heat Alert and Response System in rural British Columbia.

SettingIn 2018, a regional health authority in British Columbia (BC) initiated a multi-year project to support planning and response to extreme heat. Climate projections indicate that temperatures in the southern interior of BC will continue to increase, with concomitant negative impacts on human health. Successful climate change adaptation must include cross-sectoral action, inclusive of the health sector, to plan for and respond to climate-related events, including extreme heat.InterventionThe objective of this project was to support the development and implementation of a Heat Alert and Response System (HARS) in a small, rural community. The health authority facilitated collaboration among provincial and local governments, community organizations, and First Nations partners to assess community assets, draft a plan for extreme heat, and prepare for a community-supported response during heat events.OutcomesStakeholders expressed the importance of utilizing existing partnerships and community resources, such as physical and procedural infrastructure, in which to embed the HARS. It was imperative that the plan be simple, concise, and considerate of the community’s unique context. Educational materials and a tailored method of dissemination were important for collective and individual risk mitigation.ImplicationsA community-driven approach that utilized existing assets allowed for integration of HARS within municipal response plans and established infrastructure. The result is a sustainable public health intervention that has the potential to mitigate the negative health effects of extreme heat. Knowledge acquired through this initiative is informing similar HARS planning processes in other rural BC communities.