The difficulties of systematic reviews

The need for robust evidence to support conservation actions has driven the adoption of systematic approaches to research synthesis in ecology. However, applying systematic review to complex or open questions remains challenging, and this task is becoming more difficult as the quantity of scientific literature increases. We drew on the science of linguistics for guidance as to why the process of identifying and sorting information during systematic review remains so labor intensive, and to provide potential solutions. Several linguistic properties of peer‐reviewed corpora—including nonrandom selection of review topics, small‐world properties of semantic networks, and spatiotemporal variation in word meaning—greatly increase the effort needed to complete the systematic review process. Conversely, the resolution of these semantic complexities is a common motivation for narrative reviews, but this process is rarely enacted with the rigor applied during linguistic analysis. Therefore, linguistics provides a unifying framework for understanding some key challenges of systematic review and highlights 2 useful directions for future research. First, in cases where semantic complexity generates barriers to synthesis, ecologists should consider drawing on existing methods—such as natural language processing or the construction of research thesauri and ontologies—that provide tools for mapping and resolving that complexity. These tools could help individual researchers classify research material in a more robust manner and provide valuable guidance for future researchers on that topic. Second, a linguistic perspective highlights that scientific writing is a rich resource worthy of detailed study, an observation that can sometimes be lost during the search for data during systematic review or meta‐analysis. For example, mapping semantic networks can reveal redundancy and complementarity among scientific concepts, leading to new insights and research questions. Consequently, wider adoption of linguistic approaches may facilitate improved rigor and richness in research synthesis.     

Toward accurate and precise estimates of lion density

Reliable estimates of animal density are fundamental to understanding ecological processes and population dynamics. Furthermore, their accuracy is vital to conservation because wildlife authorities rely on estimates to make decisions. However, it is notoriously difficult to accurately estimate density for wide‐ranging carnivores that occur at low densities. In recent years, significant progress has been made in density estimation of Asian carnivores, but the methods have not been widely adapted to African carnivores, such as lions (Panthera leo). Although abundance indices for lions may produce poor inferences, they continue to be used to estimate density and inform management and policy. We used sighting data from a 3‐month survey and adapted a Bayesian spatially explicit capture‐recapture (SECR) model to estimate spatial lion density in the Maasai Mara National Reserve and surrounding conservancies in Kenya. Our unstructured spatial capture‐recapture sampling design incorporated search effort to explicitly estimate detection probability and density on a fine spatial scale, making our approach robust in the context of varying detection probabilities. Overall posterior mean lion density was estimated to be 17.08 (posterior SD 1.310) lions >1 year old/100 km², and the sex ratio was estimated at 2.2 females to 1 male. Our modeling framework and narrow posterior SD demonstrate that SECR methods can produce statistically rigorous and precise estimates of population parameters, and we argue that they should be favored over less reliable abundance indices. Furthermore, our approach is flexible enough to incorporate different data types, which enables robust population estimates over relatively short survey periods in a variety of systems. Trend analyses are essential to guide conservation decisions but are frequently based on surveys of differing reliability. We therefore call for a unified framework to assess lion numbers in key populations to improve management and policy decisions.     

Archaeological Evidence of Validity of Fish Populations on Unexploited Reefs as Proxy Targets for Modern Populations

Reef‐fish management and conservation is hindered by a lack of information on fish populations prior to large‐scale contemporary human impacts. As a result, relatively pristine sites are often used as conservation baselines for populations near sites affected by humans. This space‐for‐time approach can only be validated by sampling assemblages through time. We used archaeological remains to evaluate whether the remote, uninhabited Northwestern Hawaiian Islands (NWHI) might provide a reasonable proxy for a lightly exploited baseline in the Main Hawaiian Islands (MHI). We used molecular and morphological techniques to describe the taxonomic and size composition of the scarine parrotfish catches present in 2 archaeological assemblages from the MHI, compared metrics of these catches with modern estimates of reproductive parameters to evaluate whether catches represented by the archaeological material were consistent with sustainable fishing, and evaluated overlap between size structures represented by the archaeological material and modern survey data from the MHI and the NWHI to assess whether a space‐for‐time substitution is reasonable. The parrotfish catches represented by archaeological remains were consistent with sustainable fishing because they were dominated by large, mature individuals whose average size remained stable from prehistoric (AD approximately 1400–1700) through historic (AD 1700–1960) periods. The ancient catches were unlike populations in the MHI today. Overlap between the size structure of ancient MHI catches and modern survey data from the NWHI or the MHI was an order of magnitude greater for the NWHI comparison, a result that supports the validity of using the NWHI parrotfish data as a proxy for the MHI before accelerated, heavy human impacts in modern times. Evidencia Arqueológica de la Validez de Poblaciones de Peces en Arrecifes Sin Explotar como Objetivos de Apoderamiento para Poblaciones Actuales     

Contamination status and potential release of trace metals in a mangrove forest sediment in Ho Chi Minh City,Vietnam

Can Gio district is located in the coastal area of Ho Chi Minh City, southern Vietnam. Discharge of wastewater from Ho Chi Minh City and neighboring provinces to the rivers of Can Gio has led to concerns about the accumulation of trace metals (As, Cu, Cr, Ni, Pb, and Zn) in the coastal sediments. The main objective of this study was to assess the distribution of As, Cu, Cr, Ni, Pb, and Zn in surface and core sediments and to evaluate the contamination status in relation to local background values, as well as the potential release of these selected trace metals from sediments to the water environment. Sediment characteristization, including determination of fine fraction, pH, organic matter, and major elements (Al, Fe, Ca, K, Mg, and S), was carried out to investigate which parameters affect the trace metal enrichment. Fine fraction and Al contents were found to be the controlling proxies affecting the distribution of trace metals while other sediment characteristics did not show any clear influence on trace metals’ distribution. Although As concentrations in the sediments were much higher compared to its reference value in other areas, the enrichment factor based on local background values suggests minor contamination of this element as well as for Cr, Cu, and Pb. Risk assessment suggested a medium to very high risk of Mn, Zn, and Ni under acidification. Of importance is also that trace metals in sediments were not easily mobilized by organic complexation based on their low extractabilities by ammonium-EDTA extraction.

     

Volcano-related materials in concretes: a comprehensive review

Massive volcano-related materials (VRMs) erupted from volcanoes bring the impacts to natural environment and humanity health worldwide, which include generally volcanic ash (VA), volcanic pumice (VP), volcanic tuff (VT), etc. Considering the pozzolanic activities and mechanical characters of these materials, civil engineers propose to use them in low carbon/cement and environment-friendly concrete industries as supplementary cementitious materials (SCMs) or artificial/natural aggregates. The utilization of VRMs in concretes has attracted increasing and pressing attentions from research community. Through a literature review, this paper presents comprehensively the properties of VRMs and VRM concretes (VRMCs), including the physical and chemical properties of raw VRMs and VRMCs, and the fresh, microstructural and mechanical properties of VRMCs. Besides, considering environmental impacts and the development of long-term properties, the durability and stability properties of VRMCs also are summarized in this paper. The former focuses on the resistance properties of VRMCs when subjected to aggressive environmental impacts such as chloride, sulfate, seawater, and freezing–thawing. The latter mainly includes the fatigue, creep, heat-insulating, and expansion properties of VRMCs. This study will be helpful to promote the sustainability in concrete industries, protect natural environment, and reduce the impacts of volcano disaster. Based on this review, some main conclusions are discussed and important recommendations regarding future research on the application of VRMs in concrete industries are provided.     

The city as a refuge for insect pollinators

Research on urban insect pollinators is changing views on the biological value and ecological importance of cities. The abundance and diversity of native bee species in urban landscapes that are absent in nearby rural lands evidence the biological value and ecological importance of cities and have implications for biodiversity conservation. Lagging behind this revised image of the city are urban conservation programs that historically have invested in education and outreach rather than programs designed to achieve high‐priority species conservation results. We synthesized research on urban bee species diversity and abundance to determine how urban conservation could be repositioned to better align with new views on the ecological importance of urban landscapes. Due to insect pollinators’ relatively small functional requirements—habitat range, life cycle, and nesting behavior—relative to larger mammals, we argue that pollinators put high‐priority and high‐impact urban conservation within reach. In a rapidly urbanizing world, transforming how environmental managers view the city can improve citizen engagement and contribute to the development of more sustainable urbanization.     

Application of the QuEChERS method for the determination of organochlorine pesticide residues in Brazilian fruit pulps by GC-ECD

The Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) method was applied to the extraction of 14 organochlorine pesticides (OCPs) residues from commercial fruit pulps available in supermarkets in Fortaleza, Northeastern Brazil. The analyses were carried out by gas chromatography (GC), coupled to an electron-capture detector (ECD), and were confirmed by GC-tandem mass spectrometry (MS). The parameters of the analytical method, such as accuracy, precision, linear range, limits of detection and quantification, were determined for each pesticide. The results showed good linearity (R² ≥ 0.9916) and the overall average recoveries were considered satisfactory obtaining values between 69 and 110%, RSD of 2–15 %, except for hexachlorobenzene (HCB) in açai, acerola and guava pulp samples. The OCPs were detected in guava (α–HCH; lindane) and soursop (α, β–HCH isomers) samples. The QuEChERS method and GC–ECD were successfully used to analyze OCPs in commercially available Brazilian fruit pulps and can be applied in routine analytical laboratories.     

Assessing effects of non-native crayfish on mosquito survival

Introductions of non-native predators often reduce biodiversity and affect natural predator–prey relationships and may increase the abundance of potential disease vectors (e.g., mosquitoes) indirectly through competition or predation cascades. The Santa Monica Mountains (California, U.S.A.), situated in a global biodiversity hotspot, is an area of conservation concern due to climate change, urbanization, and the introduction of non-native species. We examined the effect of non-native crayfish (Procambarus clarkii) on an existing native predator, dragonfly nymphs (Aeshna sp.), and their mosquito larvae (Anopheles sp.) prey. We used laboratory experiments to compare the predation efficiency of both predators, separately and together, and field data on counts of dragonfly nymphs and mosquito larvae sampled from 13 local streams. We predicted a lower predation efficiency of crayfish compared with native dragonfly nymphs and a reduced predation efficiency of dragonfly nymphs in the presence of crayfish. Dragonfly nymphs were an order of magnitude more efficient predators than crayfish, and dragonfly nymph predation efficiency was reduced in the presence of crayfish. Field count data showed that populations of dragonfly nymphs and mosquito larvae were strongly correlated with crayfish presence in streams, such that sites with crayfish tended to have fewer dragonfly nymphs and more mosquito larvae. Under natural conditions, it is likely that crayfish reduce the abundance of dragonfly nymphs and their predation efficiency and thereby, directly and indirectly, lead to higher mosquito populations and a loss of ecosystem services related to disease vector control.     

Developing biodiversity indicators on a stakeholders’ opinions basis: the gypsum industry Key Performance Indicators framework

This study aims to establish a common Key Performance Indicators (KPIs) framework for reporting about the gypsum industry biodiversity at the European level. In order to integrate different opinions and to reach a consensus framework, an original participatory process approach has been developed among different stakeholder groups: Eurogypsum, European and regional authorities, university scientists, consulting offices, European and regional associations for the conservation of nature, and the extractive industry. The strategy is developed around four main steps: (1) building of a maximum set of indicators to be submitted to stakeholders based on the literature (Focus Group method); (2) evaluating the consensus about indicators through a policy Delphi survey aiming at the prioritization of indicator classes using the Analytic Hierarchy Process method (AHP) and of individual indicators; (3) testing acceptability and feasibility through analysis of Environmental Impact Assessments (EIAs) and visits to three European quarries; (4) Eurogypsum final decision and communication. The resulting framework contains a set of 11 indicators considered the most suitable for all the stakeholders. Our KPIs respond to European legislation and strategies for biodiversity. The framework aims at improving sustainability in quarries and at helping to manage biodiversity as well as to allow the creation of coherent reporting systems. The final goal is to allow for the definition of the actual biodiversity status of gypsum quarries and allow for enhancing it. The framework is adaptable to the local context of each gypsum quarry.