Trophic Pyramid Research Articles

ANALYZING STUDENT’S SCIENCE LITERACY AND CONTENT ASPECT OF INTERACTION OF ORGANISMS AND ITS ENVIRONMENT TOPIC AT SEKOLAH INDONESIA KUALA LUMPUR

The purpose of this study is to capture student’s science literacy and content aspect of interaction of organisms and its environment topic at Sekolah Indonesia Kuala Lumpur. The method of this study is quasi experiment pretest-posttest one group only. The research subject is 7th graders in Sekolah Indonesia Kuala Lumpur. Student’s science literacy on knowledge aspect is captured through 20 multiple choice questions and questionnaire about science learning. The research data is analyzed by the result of normalized gain and its effect size. There are two aspects of science literacy which are measures namely content and procedural knowledge which enhance satisfactory of n-gain 0.52 and 0.75 respectively. The effect size of those two aspects reach 1.24 which means it has strong effect. Moreover, students mostly excel on both abiotic and ecological pyramid subtopic that are correctly answered by 64.77% students. To sum up, student’s science literacy shows satisfactory results and it can be concluded that students can comprehend the topic well.

Quantification and Visualization of the Variability of Phytoplankton Assemblage in a Semi-lotic Seasonal Canal in Sundarbans, India

Canals of Sundarbans in India are highly vulnerable to anthropogenic pressures which directly or indirectly impact the biological components of such ecosystems. Being at the base of the trophic pyramid, phytoplankton is exposed to environmental stressors and the impact will be reflected in the upper strata of the aquatic food chain. Hence, phytoplankton communities along with their interrelationship with environmental parameters were assessed in Bhetkimari canal, a semi-lotic system in Indian Sundarbans during June 2017 to September 2018. Seventy-seven species under 66 genera were recorded with Cyanophyceae (34%) as a major contributor, followed by Bacillariophyceae (31%) and Chlorophyceae (22%). Diatoms dominated round the year in terms of diversity (25 species) with maximum contribution from Pennales. ANOVA (post-hoc test) showed significant temporal heterogeneity (p≤0.05) in phytoplankton distribution in the canal. The Margalef richness index (d) and Shannon-Weiner diversity index ( H′ ) were 2.59±0.43 and 2.26±0.59, respectively indicating that the environment is good and phytoplankton diversity in the system is moderate. Water temperature, dissolved oxygen, total alkalinity and nutrients (nitrate, silicate and phosphate) were the explanatory variables in shaping the phytoplankton assemblages in the canal, which was evident from Canonical correspondence analysis. The salient findings of this study can add to the existing knowledge on the abundance and distribution pattern of phytoplankton in semi-lotic canal environments, and help in planning better management of canal ecosystems for their sustainable utilization.

Energy limitation or sensitive predators? Trophic and non-trophic impacts of wastewater pollution on stream food webs.

Impacts of environmental stressors on food webs are often difficult to predict because trophic levels can respond in divergent ways, and biotic interactions may dampen or amplify responses. Here we studied food-web-level impacts of urban wastewater pollution, a widespread source of degradation that can alter stream food webs via top-down and bottom-up processes. Wastewater may (1) subsidize primary producers by decreasing nutrient limitation, inducing a wide-bottomed trophic pyramid. However, (2) wastewater may also reduce the quality and diversity of resources, which could decrease energy transfer efficiency by reducing consumer fitness, leading to predator starvation. Additionally, (3) if higher trophic levels are particularly sensitive to pollution, primary consumers could be released from predation pressure. We tested these hypotheses in 10 pairs of stream sites located upstream and downstream of urban wastewater effluents with different pollutant levels. We found that wastewater pollution reduced predator richness by ∼34%. Community size spectra (CSS) slopes were steeper downstream than upstream of wastewater effluents in all except one impact site where predators became locally extinct. Further, variation in downstream CSS slopes were correlated with pollution loads: the more polluted the stream, the steeper the CSS. We estimate that wastewater pollution decreased energy transfer efficiencies to primary consumers by ∼70%, limiting energy supply to predators. Additionally, traits increasing vulnerability to chemical pollution were overrepresented among predators, which presented compressed trophic niches (δ15 N-δ13 C) downstream of effluents. Our results show that wastewater pollution can impact stream food webs via a combination of energy limitation to consumers and extirpation of pollution-sensitive top predators. Understanding the indirect (biotically mediated) vs. direct (abiotic) mechanisms controlling responses to stress may help anticipating impacts of altered water quantity and quality, key signatures of global change.

Bottom-Heavy Trophic Pyramids Impair Methylmercury Biomagnification in the Marine Plankton Ecosystems.

Methylmercury (CH3Hg+, MMHg) in the phytoplankton and zooplankton, which form the bottom of marine food webs, is a good predictor of MMHg in top predators, including humans. Therefore, evaluating the potential exposure of MMHg to higher trophic levels (TLs) requires a better understanding of relationships between MMHg biomagnification and plankton dynamics. In this study, a coupled ecological/physical model with 366 plankton types of different sizes, biogeochemical functions, and temperature tolerance is used to simulate the relationships between MMHg biomagnification and the ecosystem structure. The study shows that the MMHg biomagnification becomes more significant with increasing TLs. Trophic magnification factors (TMFs) in the lowest two TLs show the opposite spatial pattern to TMFs in higher TLs. The low TMFs are usually associated with a short food-chain length. The less bottom-heavy trophic pyramids in the oligotrophic oceans enhance the MMHg trophic transfer. The global average TMF is increased from 2.3 to 2.8 in the warmer future with a medium climate sensitivity of 2.5 °C. Our study suggests that if there are no mitigation measures for Hg emission, MMHg in the high-trophic-level plankton is increased more dramatically in the warming future, indicating greater MMHg exposure for top predators such as humans.

Rapid decline of a four-trophic-level system over a 15-year period.

Recent climate change has produced a wide range of shifts in the phenology of species and consequent changes in the relationships among them. However, a dearth of studies exists that evaluates an entire trophic pyramid over an extended period. Here I characterize changes in several important variables on such a multitrophic suite of species, which contains two primary producers (sensitive and marsh ferns Onoclea sensibilis and Thelypteris palustris), one herbivore (caterpillars of the fern moth Herpetogramma theseusalis), one primary parasitoid (the braconid wasp Alabagrus texanus), and three facultative hyperparasitoids (including the eulophid wasp Aprostocetus sp.). I ask how the abundance of these species changes over time, how parasitism and mortality change along with the plants an herbivore selects, how the relationships between the different trophic levels change, and what effect these results play in the makeup of a trophic pyramid. Herbivores prospered most on sensitive fern, while levels of parasitism and mortality on herbivores and primary parasitoids remained relatively similar over the study period. However, facultative hyperparasitoids declined strikingly, and the few remaining individuals increased their exploitation of caterpillars (vs. Alabagrus), further decreasing the impact of the fourth trophic level. Since a previous study demonstrated that phenological change by these primary parasitoids exceeds that of their herbivore, further breakdown of the system appears likely.

BIODIVERSITY OF EDAPHIC FAUNA IN GRAY FOREST SOILS OF THE REPUBLIC OF MOLDOVA

Gray forest soils of the natural ecosystems in the central and northern zones of the Republic of Moldova are the habitat and the source of conservation and reproduction of the edaphic fauna. They represent themselves the standards of the biodiversity for soil invertebrates. Invertebrates sampling was carried out from test cuts by manual sampling of soil layers to the depth of soil fauna occurrence. The main content of invertebrates in gray soils under the forest was in the layer of 0-20 cm. In addition to the Lumbricidae family there were found the species of the Clubionidae, Hydromiidae, Scarabaeidae, Oniscidae, Tortricidae, Julidae, Curculionidae, Carabidae, Geophilidae, Tenebrionidae, Melandryidae and Formicidae families. Species of Eisenia rosea, Euomphalia strigella, Formica rufa, Tortrix viridana, Curculio glandium, Melolontha melolontha and others have been identified in three subtypes of gray forest soils of natural ecosystems. The long use of these soils in agricultural production led to the considerable decrease in the number and biomass of invertebrates and degradation of the faunal complex in general. The number of families decreased from 6-12 to 1-3. Species of Lumbricidae, Elateridae, Tortricidae and Coccinellidae have been found in arable gray forest soils. The trophic pyramids are stable in the typical virgin gray soil. The relationship between trophic levels of the edaphic fauna in the typical gray forest soil is stronger in comparison with albic and molic gray forest soils.

초등 예비교사들의 먹이그물, 생태피라미드 모형 개발 과정의 단계별 일관성과 과학적 모형 평가와의 관계 분석

This study analyzed correlations between scientific model assessments and consistency appearing in the process of pre-service elementary school teachers’ developing a food web and ecological pyramid model. As research subjects, 15 students in the third school year of education graduate school, who were taking classes of science teaching material research and teaching methods, were selected and divided into 5 groups, each of three persons. They were made to develop a food web and ecological pyramid model for about a month. Then, their reports on results, models completed, inquiry diaries and PPT presentations were all used as analysis data. The analysis results were as follows; Firstly, when analyzing consistency in the process of developing such a model, this study found consistency in two different perspectives from three groups and one perspective from two other groups. Secondly, when analyzing causes leading consistency to break-off, this study found one cause in the phase of setting learning goals, two causes in the phase of actual survey, one cause in the phase of analyzing textbooks and three causes in the phase of developing a model. Thirdly, this study discovered that as a group had higher frequency of consistency, it received higher scores from the scientific model assessment.

Gut contents and trophodynamics of riverine catfish Rita rita (Hamilton 1822) inhabiting Bangladesh waters

This study aimed to investigate the diet composition, potential food preferences, and trophodynamics (trophic level) of Riverine catfish Rita rita collected from the Surma River, Bangladesh. For this purpose, gut contents of 151 of R. rita were examined. Gut content analysis revealed that fish fed frequently on mollusks (26.36%) and arthropods (17.78%) followed by plant matters (16.96%), insects (12.75%), teleosts (12.52%), and rice seeds (6.02%). The mean trophic level was 2.411 ± 0.251, indicating that the studied fish are largely carnivorous. The highest mean trophic level was observed in February (2.794 ± 0.207), which is significantly higher than other months (P < 0.05). Moreover, diets were not significantly different among size groups. Overall, gut content and trophic level analyses revealed that R. rita is largely a carnivorous species that occupies the intermediate level in the trophic pyramid.

Using Multiple Ecological Models to Inform Environmental Decision-Making

Coastal ecosystems are experiencing degradation from compound impacts of climate change and multiple anthropogenic disturbances. These pressures often act synergistically and complicate designing effective conservation measures; consequently, large-scale coastal restoration actions become a wicked problem. The purpose of this study was to use two different food web models in a coordinated manner to inform resource managers in their assessment of the ecological effects of a large-scale marsh restoration project. A team was formed that included the model developers and outside scientists, who were asked to use available model results of the calibrated simulations of an Ecopath with Ecosim (EwE) model and a Comprehensive Aquatic Systems Model (CASM), both designed to describe the structure and energetics of the Barataria Bay, Louisiana, United States food web. Both models offer somewhat different depictions of the predator-prey and competitive interactions of species within the food web, and how environmental conditions affect the species biomass pools and energetics. Collectively, the team evaluated the strengths of each model and derived a common set of indicator variables from model outputs that provided information on the structure and energy flow of the simulated food web. Considering the different modeling structures and calibration approaches, indicators were interpreted within and between models. Use of both models enabled a robust determination that: (1) Detritus plays a vital role in the energetics of the system; (2) The food web responds to spring high flow seasons by increasing productivity through specific, dominant pathways; (3) The trophic pyramid is truncated; (4) Compared to other estuaries, this system has redundant pathways for energy transfer. These findings indicate that the food web appears to be resilient to disturbance because of a detritus energy reserve, most consumer biomass consists of low trophic level, high turnover species, and redundant energy pathways exist. This information provides context to decision-makers for assessing possible basin-scale impacts on fish and shellfish resources of a proposed large-scale restoration project. The use of multiple models in a coordinated but not overly constrained way, as demonstrated here, provides a significant step toward co-production of knowledge for use in resource management decisions.

How Do Scientists Know? Answering High School Students’ Questions with an Ecological Sampling Unit

What do animals eat? What animals are present in a habitat? How many animals are present? How was the habitat different years ago? How old is this animal? These are all questions that scientists want to answer. We know the answers to questions like these from data collected by scientists in a variety of ways. Science is evidence based, and conclusions are arrived at after multiple replicable experiments. Presented here are six ecological scenarios that demonstrate how scientists arrive at answers to population ecology questions. These lessons can be implemented as single activities that supplement a high school ecology or environmental science curricular unit or as a multiday rotation of stations in which students practice field sampling techniques used in population and community ecology, designed to answer ecological questions. Student scientists learn how to use indirect sampling methods to estimate abundance, density, age, and population size using mark–recapture, transects, and quadrats to model authentic field methods. They calculate species richness and biodiversity with a simplified Simpson’s diversity index and describe species age structure and distribution using tree rings, sheep horns, and camera trap images. Students also learn to display population data appropriately, graphing survivorship and richness vs. area and studying trophic pyramids.

High genetic diversity and low differentiation reflect the ecological versatility of the African leopard

Large carnivores are generally sensitive to ecosystem changes because their specialized diet and position at the top of the trophic pyramid is associated with small population sizes. Accordingly, low genetic diversity at the whole-genome level has been reported for all big cat species, including the widely distributed leopard. However, all previous whole-genome analyses of leopards are based on the Far Eastern Amur leopards that live at the extremity of the species' distribution and therefore are not necessarily representative of the whole species. We sequenced 53 whole genomes of African leopards. Strikingly, we found that the genomic diversity in the African leopard is 2- to 5-fold higher than in other big cats, including the Amur leopard, likely because of an exceptionally high effective population size maintained by the African leopard throughout the Pleistocene. Furthermore, we detected ongoing gene flow and very low population differentiation within African leopards compared with those of other big cats. We corroborated this by showing a complete absence of an otherwise ubiquitous equatorial forest barrier to gene flow. This sets the leopard apart from most other widely distributed large African mammals, including lions. These results revise our understanding of trophic sensitivity and highlight the remarkable resilience of the African leopard, likely because of its extraordinary habitat versatility and broad dietary niche.

Radiolysis generates a complex organosynthetic chemical network

The architectural features of cellular life and its ecologies at larger scales are built upon foundational networks of reactions between molecules that avoid a collapse to equilibrium. The search for life’s origins is, in some respects, a search for biotic network attributes in abiotic chemical systems. Radiation chemistry has long been employed to model prebiotic reaction networks, and here we report network-level analyses carried out on a compiled database of radiolysis reactions, acquired by the scientific community over decades of research. The resulting network shows robust connections between abundant geochemical reservoirs and the production of carboxylic acids, amino acids, and ribonucleotide precursors—the chemistry of which is predominantly dependent on radicals. Moreover, the network exhibits the following measurable attributes associated with biological systems: (1) the species connectivity histogram exhibits a heterogeneous (heavy-tailed) distribution, (2) overlapping families of closed-loop cycles, and (3) a hierarchical arrangement of chemical species with a bottom-heavy energy-size spectrum. The latter attribute is implicated with stability and entropy production in complex systems, notably in ecology where it is known as a trophic pyramid. Radiolysis is implicated as a driver of abiotic chemical organization and could provide insights about the complex and perhaps radical-dependent mechanisms associated with life’s origins.

Potential Herbs as Eco-green Drugs for Aquaculture: A Review

Floral resources are abundant across the globe as it forms a key role in an ecological pyramid and enriched with a bunch of medicinal properties. Historical statue reveals various plants and its materials were used for treatments of different ailments and injuries and also used as nutraceuticals in humans and animals and also used for pest control in agriculture. The practice of using plants in aquaculture started in early 1990’s for various purposes by traditional farmers. Of late, due to overuse of fertilizers, antibiotics and other chemicals in aquaculture that created the environmental issues. As an alternative to chemicals and drugs, herbal based products can be used for eco and green aquaculture for safe and healthy fish productions. There are many potential herbal plants that have been identified and used in aquaculture and we focused on a few highly important herbal plants used in aquaculture. The potential herbal plants such as Aloe vera, Phyllanthus niruri, Azardirachta indica, Curcuma longa, Allium sativum, Ocimum sanctum, Zingiber officinale, Eclipta alba, Cissus quadrangularis, Acalypha indica could be used in fish farming. These herbal plants have versatile medicinal and therapeutic properties in fish, antioxidant, antifungal, antibacterial, antioxidant and immuno-stimulant. This review article gives information about the application of herbal plants in Aquaculture as a sustainable solution for safe and healthy fish productions.

Being Isolated and Protected Is Better Than Just Being Isolated: A Case Study From the Alacranes Reef, Mexico

Isolated reefs suffered from overfishing to a lesser extent than coastal reefs systems. Nevertheless, the exploitation of coastal areas forced fishers to move offshore to compensate for their decreasing catches, helped by an overall increase in their technological capabilities. Thus, these once pristine isolated areas are under increasing threat and should be considered a protection priority. Here, we compared the fish and epibenthic community of two isolated coral reefs in the southern Gulf of Mexico: one is the Alacranes reefs a Marine Protected Area (MPA) with two No-Take Zones (NTZs) and the other is Bajos del Norte an Open Area (OA). Alacranes reef is ~135 km off the northern coast of the Yucatan Peninsula while Bajos del Norte ~160 km. Our results show that despite being isolated, the OA reefs never reach the same biomass levels of MPA or NTZ reefs which in some cases exceeded 1 ton/ha. Furthermore, 70% of the reefs within NTZ and MPA had a large predatory fish (e.g. sharks, jackfish, groupers) biomass relative contribution larger than 25%, while only two reefs in the OA had a relative piscivore contribution of more than 25%. Large predatory fish have a larger contribution to overall biomass within NTZs than MPAs reefs, even at low biomass values, suggesting that NTZ is more effective in protecting large predators. NTZ and MPA reefs also showed from 5 to 10% higher coral cover than OA which had a higher erect algae cover (~22.9%). Indicating that the disruption of the trophic pyramid caused by the fishing pressure in OA reefs is reflecting on the trophic cascades controlling the benthic communities balance. These isolated areas represent the last pillars of natural diversity and are under such an increasing anthropogenic pressure that just being isolated is not enough anymore to guarantee a safe zone from detrimental activities like overfishing. Immediate establishment of protective NTZ is needed to maintain the role they play as a natural wilderness capital.

Increasing temperature and productivity change biomass, trophic pyramids and community-level omega-3 fatty acid content in subarctic lake food webs.

Climate change in the Arctic is outpacing the global average and land-use is intensifying due to exploitation of previously inaccessible or unprofitable natural resources. A comprehensive understanding of how the joint effects of changing climate and productivity modify lake food web structure, biomass, trophic pyramid shape and abundance of physiologically essential biomolecules (omega-3 fatty acids) in the biotic community is lacking. We conducted a space-for-time study in 20 subarctic lakes spanning a climatic (+3.2°C and precipitation: +30%) and chemical (dissolved organic carbon: +10mg/L, total phosphorus: +45µg/L and total nitrogen: +1,000µg/L) gradient to test how temperature and productivity jointly affect the structure, biomass and community fatty acid content (eicosapentaenoic acid [EPA] and docosahexaenoic acid [DHA]) of whole food webs. Increasing temperature and productivity shifted lake communities towards dominance of warmer, murky-water-adapted taxa, with a general increase in the biomass of primary producers, and secondary and tertiary consumers, while primary invertebrate consumers did not show equally clear trends. This process altered various trophic pyramid structures towards an hour glass shape in the warmest and most productive lakes. Increasing temperature and productivity had negative fatty acid content trends (mg EPA+DHA/g dry weight) in primary producers and primary consumers, but not in secondary nor tertiary fish consumers. The massive biomass increment of fish led to increasing areal fatty acid content (kg EPA+DHA/ha) towards increasingly warmer, more productive lakes, but there were no significant trends in other trophic levels. Increasing temperature and productivity are shifting subarctic lake communities towards systems characterized by increasing dominance of cyanobacteria and cyprinid fish, although decreasing quality in terms of EPA+DHA content was observed only in phytoplankton, zooplankton and profundal benthos.

Alimentary exposure and elimination routes of rare earth elements (REE) in marine mammals from the Baltic Sea and Antarctic coast

Marine mammals found at the top of the trophic pyramid are excellent bioindicators of pollutants in the marine environment, the concentrations of which increase along with the trophic level of the organism. As these animals are usually protected species, their contamination has to be assessed non-invasively by analysing excrement and epidermal structures such as fur or claws. The present study involved testing the excrement and fur of the grey seal (Halichoerus grypus) from the Southern Baltic coast and the Southern elephant seal (Mirounga leonine) from Admiralty Bay, along with fish muscle (food) and the lithological background of both areas, for the presence of rare earth elements (REE). The soil on the Baltic coast is characterized by the predomination of light rare earth elements (LREE): yttrium, lanthanum and cerium (∑REE = 7.86 mg·kg−1 dw). In the soil and bedrock of Admiralty Bay all REEs were found except for terbium, thulium and lutetium (∑REE = 96.1 mg·kg−1 dw). The REE levels found in the muscles of Baltic herring (∑REE = 0.057 mg·kg−1 ww) were lower than those in the muscles of marbled rockcod (∑REE = 0.540 mg·kg−1 ww). The situation was analogous in the mammals, with the REE concentrations in grey seal fur (∑REE = 0.489 mg·kg−1 dw) and excrement (∑REE = 0.676 mg·kg−1 dw) being lower than those found in the fur (∑REE = 10.1 mg·kg−1 dw) and excrement (∑REE = 83.6 mg·kg−1 dw) of the elephant seal. The LREE/HREE partition coefficients in the grey seal excrement (3.37) and its fur (4.00), but also in the faeces of the elephant seal (2.63) and its fur (2.65), indicate that in each species the process of elimination from the body occurs in similar proportions.

Trophic pyramids reorganize when food web architecture fails to adjust to ocean change.

As human activities intensify, the structures of ecosystems and their food webs often reorganize. Through the study of mesocosms harboring a diverse benthic coastal community, we reveal that food web architecture can be inflexible under ocean warming and acidification and unable to compensate for the decline or proliferation of taxa. Key stabilizing processes, including functional redundancy, trophic compensation, and species substitution, were largely absent under future climate conditions. A trophic pyramid emerged in which biomass expanded at the base and top but contracted in the center. This structure may characterize a transitionary state before collapse into shortened, bottom-heavy food webs that characterize ecosystems subject to persistent abiotic stress. We show that where food web architecture lacks adjustability, the adaptive capacity of ecosystems to global change is weak and ecosystem degradation likely.

A field study on the effects of combined biomanipulation on the water quality of a eutrophic lake

Lake eutrophication has become a serious environmental problem in China. Manipulations covering more elements of trophic pyramid are methods for lakes to obtain clear water state and should be studied in detail. In the present study, Meishan Dongpo Lake was divided into two parts, and a combined biomanipulation project was conducted in one part (RLake), and the other part was used as a control (CLake). Species of submerged-plant, fish, macrobenthos, and zooplankton were screened and a certain number of them were added to adjust the eco-chain in RLake. After restoration, the coverage of submerged macrophytes reached >85%; zooplankton greater than 0.6 mm in size increased in number, and the ratio of zooplankton biomass to chlorophyll-a (Chl-a) concentration increased. The dominant fish species changed, and disturbance of the sediment was reduced. The average density of mollusks in RLake was 111.5 ± 19.8 ind m−2, which was much higher than that in CLake (36.7 ± 2.1 ind m−2). Water quality and clarity were substantially improved, and nutrient concentrations, particularly total phosphorus, total nitrogen, and Chl-a were significantly reduced. The aquatic community parameters were negatively correlated with the nutrient parameters and Chl-a. The ecological restoration have adjusted the aquatic ecosystem in RLake, and many positive feedback effects among the aquatic communities made them remove internal nutrients and Chl-a more efficiently.

Salty, mild, and low plant biomass grasslands increase top‐heaviness of invertebrate trophic pyramids

AbstractAimMultiple hypotheses predict how gradients of nutrient availability, plant biomass, and temperature shape trophic pyramids. We aim to disentangle the simultaneous influence of those factors and their indirect effects on trophic structure and individual trophic levels.LocationUnited States.Time period2017.Major taxa studiedInvertebrates.MethodsTo examine differences in trophic pyramid shape and abundance within trophic levels and across ecological gradients, we conducted 54 standardized surveys of invertebrate communities in North American grasslands. We tested for the direct and indirect effects of plant biomass, temperature, sodium (Na), other essential elements (e.g. N, P, and K), and toxic heavy metals, (e.g. Ar and Pb) in plant tissue on both individual trophic levels, and trophic pyramid shape, estimated as the community trophic mean (CTM).ResultsPlant sodium increased CTM, indicating that high plant sodium concentrations are associated with top‐heavy invertebrate trophic pyramids. Sites with higher plant biomass had higher proportions of herbivores compared to higher trophic levels. Finally, increasing temperature resulted in more top‐heavy trophic pyramids. Overall, plant biomass, temperature, and plant chemistry directly and indirectly affected the abundances within different trophic levels, highlighting the complexity of factors regulating trophic structure.Main conclusionsTrophic structure of grassland invertebrate communities is strongly influenced by plant sodium, plant biomass, and to a lesser extent, temperature. Grasslands occupy 30% of the Earth’s terrestrial surface and are an imperiled ecosystem due to conversion to row crop agriculture. As biogeochemistry and temperature in the Anthropocene are increasingly modified, our results have considerable implications for the trophic structure of future grassland communities.

Fishing restrictions and remoteness deliver conservation outcomes for Indonesia's coral reef fisheries

AbstractCoral reef fisheries depend on reef fish biomass to support ecosystem functioning and sustainable fisheries. Here, we evaluated coral reefs across 4,000 km of the Indonesian archipelago to reveal a large gradient of biomass, from &lt;100 kg/ha to &gt;17,000 kg/ha. Trophic pyramids characterized by planktivore dominance emerged at high biomass, suggesting the importance of pelagic pathways for reef productivity. Total biomass and the biomass of most trophic groups were higher within gear restricted and no‐take management, but the greatest biomass was found on unmanaged remote reefs. Within marine protected areas (MPAs), 41.6% and 43.6% of gear restricted and no‐take zones, respectively, met a global biomass target of 500 kg/ha, compared with 71.8% of remote sites. To improve conservation outcomes for Indonesia's biodiverse and economically important coral reef fisheries, our results suggest to: (1) strengthen management within Indonesia's existing MPAs and (2) precautionarily manage remote reefs with high biomass.