Search

Globalization has spread thousands of invasive insect species into new world regions, 1,2,3 causing severe losses in ecosystem services. Previous work proposed that plant invasions facilitate insect invasions through the creation of niches for non-native herbivores. 3,4,5,6 Despite the impact of insect invasions, a comprehensive understanding is lacking on how invasion success varies among insect feeding groups. We therefore compiled the predominant larval trophic groups (herbivores, predators, parasites, detritivores, and brood-carers) for 5,839 non-native insect species in nine world regions to compare (1) proportions of species in each group between non-native species and the world's fauna, (2) how invasion success for each trophic group has changed over the last three centuries, and (3) how historical herbivore invasions are related to plant invasions over time and parasite invasions are related to herbivores. We find that herbivores represent a significantly larger proportion (52.4%) among non-native insects compared with the world fauna (38.4%), whereas proportions of non-native detritivores (including fungivores), predators, and brood-carers are significantly lower; parasite proportions do not significantly differ. Predators and detritivores dominated among invasions in the 18th century but subsequently diminished, likely due to changing invasion pathways, whereas proportions of herbivores, parasites, and brood-carers increased over time. We found herbivore invasions to lag 80 years behind plant invasions, whereas parasitoids appear to co-invade with their herbivore hosts. The dominance of herbivores among non-native insects and their strong cross-correlation with plant invasions further strengthens the hypothesis that plant invasions drive the global rise in numbers of non-native insects. • Herbivores are over-represented among non-native insects worldwide • Predator and detritivore invasion proportions declined since the 18th century • Herbivore invasion rates are related to historical lagged plant invasions Among non-native insects, herbivores are over-represented compared to the world fauna, and proportions are increasing. In contrast, non-native detritivores and predators are under-represented, with proportions declining. These results are consistent with a mechanism of plant invasions facilitating insect herbivore invasions via niche creation. [ABSTRACT FROM AUTHOR]

From soil to freshwater ecosystems, decomposition can be conceived as the result of interactions between organic matter and a diversity of organisms. This function is driven in part by detritivores, invertebrates that feed on detritus or graze on its associated microbes and that have a significant but extremely variable contribution to decomposition.In order to better understand and predict detritivore–detritus pairwise interactions, we propose a conceptual framework, called Detri2match, to study the consumption of detritus by detritivores, using a trait‐matching approach at the individual detritivore level. Here, we focus on the interaction between saprophagous detritivores that fragment plant detritus.We propose a novel definition of a saprophagous detritivore as an animal that consumes plant detritus when its traits match sufficiently the traits of its resource, passing through five interaction facets of consumption. These include (1) a spatial match rule regarding the encounter, (2) a biomechanical match rule regarding ingestion, (3) a digestive match rule regarding assimilation, (4) an energetic match rule regarding the fulfilment of metabolic needs and (5) a nutritional match rule regarding the fulfilment of chemical element needs in adapted proportions.The main goal of this framework is to guide future research to establish generic rules of misunderstood detritus–detritivore pairwise interactions by identifying relevant interaction facets and their key associated traits for both detritivores and detritus. This investigation should be conducted over the temporal variability of trait‐matching constraints throughout the whole decomposition process. Coupled with adequate accumulation of trait information, the Detri2match framework could also facilitate predictions by inference of non‐tested pairwise detritivore–litter interactions.We also outline conceptual, methodological and analytical challenges of this framework. The main challenge would be to scale up these pairwise rules at the detrital network level and to test their genericity, which would contribute to a better understanding of the functioning of the detrital network and its contribution to decomposition. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Increased temperatures are altering rates of organic matter (OM) breakdown in stream ecosystems with implications for carbon (C) cycling in the face of global change. The metabolic theory of ecology (MTE) provides a framework for predicting temperature effects on OM breakdown, but differences in the temperature dependence of breakdown driven by different organismal groups (i.e., microorganisms vs. invertebrate detritivores) and litter species remain unresolved. Over two years, we conducted 12 60‐day leaf litterbag incubations in 20 headwater streams in the southern Appalachian Mountains (USA). We compared temperature dependence (as activation energy, Ea) between microbial and detritivore‐mediated breakdown, and between a highly recalcitrant (Rhododendron maximum) and a relatively labile (Acer rubrum) leaf species. Detritivore‐mediated breakdown had a higher Ea than microbial breakdown for both leaf species (Rhododendron: 1.48 > 0.56 eV; Acer: 0.97 > 0.29 eV), and Rhododendron breakdown had a higher Ea than Acer breakdown for both organismal groups. Similarly, the Ea of total (coarse‐mesh) Rhododendron breakdown was higher than the Ea of total Acer breakdown (0.89 > 0.52 eV). These effects for total breakdown were large, implying that the number of days to 95% mass loss would decline by 40% for Rhododendron and 26% for Acer between 12°C (our mean temperature value) and 16°C (+4°C, reflecting projected increases in global surface temperature due to climate change). Despite patterns in Ea, overall breakdown rates were higher for microbes than detritivores, and for Acer than Rhododendron over most of our temperature gradient. Additionally, the Ea for a subset of the microbial breakdown data declined from 0.40 to 0.22 eV when fungal biomass was included as a model predictor, highlighting the key role of fungi in determining the temperature dependence of litter breakdown. Our results imply that, as streams warm, routing of leaf litter C to detritivore‐mediated fates will increase faster than predicted by previous studies and MTE, especially for labile litter. As temperatures rise, earlier depletion of autumn‐shed, labile leaf litter combined with rapid breakdown rates of recalcitrant litter could exacerbate seasonal resource limitation and alter carbon storage and transport dynamics in temperate headwater stream networks. [ABSTRACT FROM AUTHOR]

Although intraspecific trait variation is increasingly recognized as affecting ecosystem processes, few studies have examined the ecological significance of among-population variation in behavioral traits in natural ecosystems. In freshwater habitats, crayfish are consumers that can influence ecosystem structure (e.g., macroinvertebrate communities) and function (e.g., leaf litter breakdown). To test whether crayfish behavioral traits (activity, boldness, and foraging voracity) are major contributors of leaf litter breakdown rates in the field, we collected rusty crayfish (Faxonius rusticus) from eight streams across the midwestern USA and measured behaviors using laboratory assays. At the same streams, we measured breakdown rates of leaf packs that were accessible or inaccessible to crayfish. Our results provide evidence that among-population variation in crayfish boldness and foraging voracity was a strong predictor of leaf litter breakdown rates, even after accounting for commonly appreciated environmental drivers (water temperature and human land use). Our results suggest that less bold rusty populations (i.e., emerged from shelter more slowly) had greater direct impacts on leaf litter breakdown than bold populations (P = 0.001, r2 = 0.85), potentially because leaf packs can be both a shelter and food resource to crayfish. Additionally, we found that foraging voracity was negatively related to breakdown rates in leaf packs that were inaccessible to crayfish (P = 0.025, r2 = 0.60), potentially due to a trophic cascade from crayfish preying on other invertebrates that consume leaf litter. Overall, our results add to the growing evidence that trait variation in animals may be important for understanding freshwater ecosystem functioning. [ABSTRACT FROM AUTHOR]

While some streams have dense populations of aquatic detritivorous isopods, research on the colonization of leaf packs typically focuses on aquatic insects. To determine whether shifts in dominant local forest species might impact isopod populations, we placed leaf packs of red/sugar maple, American beech, and red oak on the substratum of riffles and pools in Cedar Creek (Allentown, PA, USA) in April 2019. We retrieved the packs after one week, re-deployed them, and re-collected them after two weeks of submersion, enumerating the number of isopods (Lirceus sp.) upon each retrieval. Surprisingly, neither the species of leaf nor the stream microhabitat significantly affected the number of isopods. However, the duration of leaf conditioning was important; significantly more isopods inhabited leaves after two weeks of submersion than after only one week. Maple and oak leaves displayed significantly more skeletonization after two weeks than the beech leaves, which remained intact. However, the similar numbers of isopods across leaf species suggest either the presence of acceptable, consumable microbial communities on all three species of leaves or that a tradeoff exists between the value of food and the importance of refuge provided by intact leaves. [ABSTRACT FROM AUTHOR]

While some streams have dense populations of aquatic detritivorous isopods, research on the colonization of leaf packs typically focuses on aquatic insects. To determine whether shifts in dominant local forest species might impact isopod populations, we placed leaf packs of red/sugar maple, American beech, and red oak on the substratum of riffles and pools in Cedar Creek (Allentown, PA, USA) in April 2019. We retrieved the packs after one week, re-deployed them, and re-collected them after two weeks of submersion, enumerating the number of isopods (Lirceus sp.) upon each retrieval. Surprisingly, neither the species of leaf nor the stream microhabitat significantly affected the number of isopods. However, the duration of leaf conditioning was important; significantly more isopods inhabited leaves after two weeks of submersion than after only one week. Maple and oak leaves displayed significantly more skeletonization after two weeks than the beech leaves, which remained intact. However, the similar numbers of isopods across leaf species suggest either the presence of acceptable, consumable microbial communities on all three species of leaves or that a tradeoff exists between the value of food and the importance of refuge provided by intact leaves.

Although belowground invasive species are probably equally widespread and as important as their aboveground counterparts, they remain understudied, and their impacts are likely to be stronger when these invaders act as ecosystem engineers and differ functionally from native species. This is the case in regions historically devoid of native earthworms, such as parts of northern North America, which are now experiencing an invasion by European earthworms. Although invasive earthworms have been reported to have multiple consequences for native communities and ecosystem functioning, this knowledge is mostly based on observational studies, and the mechanisms underlying their cascading impacts need to be investigated. Here, we thus investigated the sequence of events, i.e., ecological cascades following earthworm invasion, that have rarely been studied before, in a two-year field experiment. We expected that the changes in soil abiotic properties observed following invasion would coincide with changes in plant community diversity and community trait composition, as well as in alterations in above- and belowground ecosystem functions. To test these hypotheses, we set up a field experiment that ran for two years in a forest in Alberta (Canada) to investigate soil properties and understory plant community composition in response to invasive earthworms. Our study shows that invasive European earthworms alter several soil abiotic properties (i.e., soil nutrient content, and pH) after two years of experiment. Invasive earthworm effects varied with soil depth for some soil properties (i.e., soil pH, water-stable aggregates, nitrogen, and microbial basal respiration), but we did not find any significant earthworm effect on soil water content, bulk density, or the total soil microbial biomass independently of the soil layer. Moreover, invasive earthworms did not affect plant community composition and only slightly affected community diversity in this short-term experiment. The minor changes observed in plant functional group composition are thus potentially the first signs of invasive-earthworm effects on plant communities. Our research provides experimental evidence that previously reported observational effects of invasive earthworms on soil properties are indeed causal and already significant after two years of invasion. These changes in soil properties are likely to have cascading effects on plant community composition, functional diversity, and ecosystem functioning, but such effects may take longer than two years to materialize. [ABSTRACT FROM AUTHOR]

Large mammalian herbivores substantially impact ecosystem functioning. As their populations are dramatically altered globally, disentangling their consumptive and non‐consumptive effects is critical to advance mechanistic understanding and improve prediction of effects over ecosystem and Earth‐system spatial extents. Mathematical models have played an important role in clarifying potential mechanisms of herbivore zoogeochemistry, based mostly on their consumptive effects as primary consumers and recyclers of organic and inorganic matter via defecation and urination. Trampling is a ubiquitous effect among walking vertebrates, but the consequences and potential mechanisms of trampling in diverse environments remain poorly understood.We derive a novel mathematical model of large mammalian herbivore effects on ecosystem nitrogen cycling, focusing on how trampling and environmental context impact soil processes. We model herbivore trampling with a linear positive or negative additive effect on soil‐mediated nitrogen cycling processes.Combining analytical and numerical analyses, we find trampling by large mammalian herbivores is likely to decrease nitrogen mineralisation rate across diverse environments, such as temperate grassland and boreal forest. These effects are mediated by multiple potential mechanisms, including trampling‐induced changes to detritivore biomass and functioning (e.g. rate of organic matter consumption). We also uncover scenarios where trampling can increase nitrogen mineralisation rate, contingent on the environment‐specific relative sensitivity of detritivore mineral‐nitrogen release and detritivore mortality, to trampling.In contrast to some consumptive mechanisms, our results suggest the pace of soil nitrogen cycling prior to trampling has little influence over the direction of the trampling net effect on nitrogen mineralisation, but that net effects may be greater in slow‐cycling systems (e.g. boreal forests) than in fast‐cycling systems (e.g. grasslands).Our model clarifies the potential consequences of previously overlooked mechanisms of zoogeochemistry that are common to all terrestrial biomes. Our results provide empirically testable predictions to guide future progress in empirical and theoretical studies of herbivore effects in diverse environmental contexts. Resolving ecological contingencies around animal consumptive and non‐consumptive effects will improve whole‐ecosystem management efforts such as restoration and rewilding. [ABSTRACT FROM AUTHOR]

To explore the mixing effect of litter decomposition and the role of detritivores, we conducted a laboratory- based microcosm experiment to study the influence of detritivores on litter mixture decomposition by using two litter species with contrasting quality, i.e., Cinnamomum camphora and Michelia X alba, and a detritivore (isopoda). After 100 days incubation, the decomposition rate of litter mixture was 52.1%, slower than that of M. alba (62.6%) and significantly faster than that of C. camphora (33.6%). The addition of isopods significantly increased litter decomposition rate, with C. camphora, M. alba, and the mixture increased by 14.4%, 20.1% and 22.1%, respectively. There was no significant mixing effect without isopods. Adding isopods significantly promoted the mixing effect of litter decomposition, with a value of the litter mixture decomposition effect of 8.6%. The detritivores increased litter decomposition rate and mixing effect through increasing consumption of litter with better quality. [ABSTRACT FROM AUTHOR]

Biological invasions have major impacts on a variety of ecosystems and threaten native biodiversity. Earthworms have been absent from northern parts of North America since the last ice age, but non‐native earthworms were recently introduced there and are now being spread by human activities. While past work has shown that plant communities in earthworm‐invaded areas change towards a lower diversity mainly dominated by grasses, the underlying mechanisms related to changes in the biotic interactions of the plants are not well understood. Here, we used a trait‐based approach to study the effect of earthworms on interspecific plant competition and aboveground herbivory. We conducted a microcosm experiment in a growth chamber with a full‐factorial design using three plant species native to northern North American deciduous forests, Poa palustris (grass), Symphyotrichum laeve (herb) and Vicia americana (legume), either growing in monoculture or in a mixture of three. These plant community treatments were crossed with earthworm (presence or absence) and herbivore (presence or absence) treatments. Eight out of the fourteen above‐ and belowground plant functional traits studied were significantly affected by earthworms, either by a general effect or in interaction with plant species identity, plant diversity level and/or herbivore presence. Earthworms increased the aboveground productivity and the number of inflorescences of the grass P. palustris. Further, earthworms and herbivores together affected root tissue density of P. palustris and the specific leaf area of V. americana. In this study, earthworm presence gave a competitive advantage to the grass species P. palustris by inducing changes in plant functional traits. Our results suggest that invasive earthworms can alter competitive and multitrophic interactions of plants, shedding light on some of the mechanisms behind invasive earthworm‐induced plant community changes in northern North America forests. [ABSTRACT FROM AUTHOR]

Copyright of Biotropica is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Simple Summary: Changes in precipitation patterns can significantly alter biological processes and associated ecosystem functions. This study aimed to investigate the impacts of rainfall intensity and timing on the structure of dung beetle assemblage and dung mass loss rate in a Tibetan alpine meadow. The results revealed that exposure to rainfall within a 2 h timeframe, regardless of rainfall intensity, significantly reduced the rate of dung mass loss. However, this decrease was not attributed to the activity of dung beetles. Earlier rainfall tended to decrease species richness of dung beetles, while heavier rainfall significantly decreased beetle abundance. These findings suggest that changes in precipitation patterns can influence both the assemblage of dung beetles and the rate of dung decomposition, but may also decouple their relationship under a certain circumstance. The variability in local biological processes and ecosystem functions deserves greater attention within a global climate change scenario. Changes in precipitation patterns, including rainfall intensity and rainfall timing, have been extensively demonstrated to impact biological processes and associated ecosystem functions. However, less attention has been paid to the effects of rainfall intensity and rainfall timing on the assembly of detritivore communities and the decomposition rate of detritus such as animal dung. In a grazed alpine meadow on the eastern Qinghai–Tibet Plateau, we conducted a manipulative experiment involving two levels of rainfall intensity (heavy rainfall, 1000 mL/5 min; light rainfall, 100 mL/5 min) and five levels of rainfall timing (0, 2, 4, 24, and 48 h after yak dung deposition). The aim was to determine the effects of rainfall intensity, timing, and their interaction on the assemblage of dung beetles and dung removal rate during the early stage (i.e., 96 h after yak dung deposition) of dung decomposition. Light rainfall significantly increased species richness in the treatment of 48 h after dung pats were deposited. Heavy rainfall significantly decreased beetle abundance in both the 0 h and 48 h treatments while light rainfall had no effect on beetle abundance. Dung mass loss was significant lower in the 2 h treatment compared to other treatments regardless of rainfall intensity. The structural equation model further revealed that the species richness of dung beetles and dung mass loss were significantly affected by rainfall timing but not by rainfall intensity. However, no significant relationships were observed between any variables examined. These findings suggest that changes in precipitation patterns can influence both the structure of dung beetles and the rate of dung decomposition but may also decouple their relationship under a certain circumstance. Therefore, it is crucial to pay greater attention to fully understand local variability between the biological processes and ecosystem functions within a global climate change scenario. [ABSTRACT FROM AUTHOR]

Leaf litter decomposition is a significant ecosystem process for streams' energy provisioning, while species‐specific decomposition rates often form a continuum from slow to fast decomposing species allowing for resources' availability to stream consumers over a longer time period after leaf fall. Leaf litter mixtures in streams typically comprise leaf species varying in their traits, allowing for litter diversity effects on decomposition. At the same time, agricultural land use, habitat characteristics, water quality and invertebrate composition modulate leaf litter decomposition. To identify leaf litter diversity effects and disentangle the roles of agricultural intensity, habitat characteristics, water quality and invertebrate composition for leaf litter processing in streams, we quantified leaf litter decomposition of three leaf species covering a gradient from slow to fast decomposing species, tested either individually or as a three‐species mixture. The study was conducted over 21 days across 18 streams with a gradient of agricultural intensity (percent agricultural land use) in their catchments. We found leaf litter diversity effects in terms of complementarity under low to intermediate agricultural intensity, given that slow decomposing leaf species decomposed almost twice as fast in the three‐species mixture compared to the observations on individual leaf species. This leaf litter diversity effect decreased with increasing agricultural intensity, suggesting that agriculture weakens the biodiversity–ecosystem functioning relationship. However, pathways by which agriculture affected decomposition differed between single‐species and mixed‐species scenarios. For the single‐species scenario, negative effects of agriculture appeared to be mediated through effects on the proportion of sensitive detritivore species and altered habitat characteristics. For the mixed‐species scenario, altered water quality negatively affected the proportion of sensitive detritivore species, in turn reducing the diversity effect on functioning. Our results suggest that the weakened biodiversity–ecosystem functioning relationship under increasing agricultural intensity might be a significant factor threatening carbon cycling and food web integrity in streams. [ABSTRACT FROM AUTHOR]

Food webs can be conceptualized as being powered by energy derived from living and dead vegetation, respectively. Most food web research has focused on "green food webs" which begin with the consumption of living vegetation by herbivores. However, "brown food webs" which stem from the consumption of senescent vegetation by detritivores are also an important channel of energy transfer. In theory, herbivores have the potential to disrupt brown food webs by consuming plant material before it can senesce and become available for detritivores. Here we investigate the effects that grazing by kangaroos, whose population had irrupted partly due to the absence of an apex predator, has on the brown food web in an arid environment. We compared the cover of living and dead vegetation, the abundances of detritivorous termites and their predators inside one ha herbivore exclosures and nearby control plots. Results show there was more cover of living and dead vegetation inside the exclosures. Similarly, abundances of termites and small vertebrate predators of termites were greater inside the exclosures. Our study provides evidence that consumption of plant material by irruptive herbivores can disrupt the functioning of the brown food web by reducing the flow of energy from plant biomass to termites which in turn translates to reduced abundances of termites and small vertebrates that feed on termites. Our findings have implications for conservation and management because they shed light on a previously unconsidered threat to the functioning of arid ecosystems, disruption of brown food webs by irruptive herbivores. [ABSTRACT FROM AUTHOR]

Stoneflies are a globally threatened aquatic insect order. In Arkansas, a diverse group of winter stonefly (Capniidae: Allocapnia) have not been surveyed since the 1980s, likely because species-level identification requires the rarely-collected adult form. Allocapnia mohri, a regional endemic, was previously commonly found in mountainous, intermittent streams from the Ouachita Mountains ecoregion north to the Ozark Highlands, but no species distributional models including land use or climate variables exist to our knowledge. We collected adults from 71 stream reaches from the historic Arkansas range from November to April 2020 and 2021. We modeled distributions using random forest (RF) models populated with landscape, climate, and both data to determine which were most predictive of species presence. Correlations between landscape or climate variables and presence were examined using multiple logistic regression. The landscape RF models performed better than the climate or landscape + climate RF models. A. mohri presence sites tended to have a greater elevation, a lower mean July temperature, and a greater percentage of very slow infiltration soils in the watershed, compared to absence sites. A. mohri was absent at the Ouachita Mountains sites and may be experiencing a range contraction or migration northward.

Stoneflies are a globally threatened aquatic insect order. In Arkansas, a diverse group of winter stonefly (Capniidae: Allocapnia) have not been surveyed since the 1980s, likely because species-level identification requires the rarely-collected adult form. Allocapnia mohri, a regional endemic, was previously commonly found in mountainous, intermittent streams from the Ouachita Mountains ecoregion north to the Ozark Highlands, but no species distributional models including land use or climate variables exist to our knowledge. We collected adults from 71 stream reaches from the historic Arkansas range from November to April 2020 and 2021. We modeled distributions using random forest (RF) models populated with landscape, climate, and both data to determine which were most predictive of species presence. Correlations between landscape or climate variables and presence were examined using multiple logistic regression. The landscape RF models performed better than the climate or landscape + climate RF models. A. mohri presence sites tended to have a greater elevation, a lower mean July temperature, and a greater percentage of very slow infiltration soils in the watershed, compared to absence sites. A. mohri was absent at the Ouachita Mountains sites and may be experiencing a range contraction or migration northward. [ABSTRACT FROM AUTHOR]

Changes in precipitation patterns, including rainfall intensity and rainfall timing, have been extensively demonstrated to impact biological processes and associated ecosystem functions. However, less attention has been paid to the effects of rainfall intensity and rainfall timing on the assembly of detritivore communities and the decomposition rate of detritus such as animal dung. In a grazed alpine meadow on the eastern Qinghai–Tibet Plateau, we conducted a manipulative experiment involving two levels of rainfall intensity (heavy rainfall, 1000 mL/5 min; light rainfall, 100 mL/5 min) and five levels of rainfall timing (0, 2, 4, 24, and 48 h after yak dung deposition). The aim was to determine the effects of rainfall intensity, timing, and their interaction on the assemblage of dung beetles and dung removal rate during the early stage (i.e., 96 h after yak dung deposition) of dung decomposition. Light rainfall significantly increased species richness in the treatment of 48 h after dung pats were deposited. Heavy rainfall significantly decreased beetle abundance in both the 0 h and 48 h treatments while light rainfall had no effect on beetle abundance. Dung mass loss was significant lower in the 2 h treatment compared to other treatments regardless of rainfall intensity. The structural equation model further revealed that the species richness of dung beetles and dung mass loss were significantly affected by rainfall timing but not by rainfall intensity. However, no significant relationships were observed between any variables examined. These findings suggest that changes in precipitation patterns can influence both the structure of dung beetles and the rate of dung decomposition but may also decouple their relationship under a certain circumstance. Therefore, it is crucial to pay greater attention to fully understand local variability between the biological processes and ecosystem functions within a global climate change scenario.

Surveys on detritivorous moths were carried out at three locations in Kyushu, Japan, in 2019, using bait traps. The trap material consisted of dead leaves or rice straw, baited with dog food, chicken manure, or bat guano. A total of 293 moth individuals, comprising 25 species belonging to 17 families, were trapped during the experiment. The emerged moths included 285 detritivore individuals of 17 species in nine families and eight herbivore individuals of eight different families. Most moth individuals emerged from the traps made of dead leaves with dog food, which contains several nutrients, as the bait. Of these individuals, species such as Phaeoses sp. (Tineidae) and Pyralis farinalis(Pyralidae), which often emerge from bird nests but are difficult to collect, were also found. This is the first study to collect detritivorous moths using traps with different baits.

Anthropogenic stressors are predicted to alter biodiversity and ecosystem functioning worldwide. However, scaling up from species to ecosystem responses poses a challenge, as species and functional groups can exhibit different capacities to adapt, acclimate, and compensate under changing environments. We used a naturally acidified seagrass ecosystem (the endemic Mediterranean Posidonia oceanica) as a model system to examine how ocean acidification (OA) modifies the community structure and functioning of plant detritivores, which play vital roles in the coastal nutrient cycling and food web dynamics. In seagrass beds associated with volcanic CO2 vents (Ischia, Italy), we quantified the effects of OA on seagrass decomposition by deploying litterbags in three distinct pH zones (i.e., ambient, low, extreme low pH), which differed in the mean and variability of seawater pH. We replicated the study in two discrete vents for 117 days (litterbags sampled on day 5, 10, 28, 55, and 117). Acidification reduced seagrass detritivore richness and diversity through the loss of less abundant, pH‐sensitive species but increased the abundance of the dominant detritivore (amphipod Gammarella fucicola). Such compensatory shifts in species abundance caused more than a threefold increase in the total detritivore abundance in lower pH zones. These community changes were associated with increased consumption (52%–112%) and decay of seagrass detritus (up to 67% faster decomposition rate for the slow‐decaying, refractory detrital pool) under acidification. Seagrass detritus deployed in acidified zones showed increased N content and decreased C:N ratio, indicating that altered microbial activities under OA may have affected the decay process. The findings suggest that OA could restructure consumer assemblages and modify plant decomposition in blue carbon ecosystems, which may have important implications for carbon sequestration, nutrient recycling, and trophic transfer. Our study highlights the importance of within‐community response variability and compensatory processes in modulating ecosystem functions under extreme global change scenarios. [ABSTRACT FROM AUTHOR]

Seagrass, systems export significant amounts of their primary production as large detritus (i.e. macrophytodetritus). Accumulations of exported macrophytodetritus (AEM) are found in many areas in coastal environment. Dead seagrass leaves are often a dominant component of these accumulations, offering shelter and/or food to numerous organisms. AEM are particular habitats, different from donor habitats (i.e. seagrass meadow, kelp or macroalgae habitats) and with their own characteristics and dynamics. They have received less attention than donor habitats despite the fact they often connect different coastal habitats, are the place of intense remineralization processes and shelter associated detritus food web. As for seagrass meadows themselves, AEM are potentially affected by global change and by tropicalization processes. Here, we review briefly general characteristic of AEM with a focus on Mediterranean Sea and Western Australia and we provide some hypotheses concerning their tropicalization in a near future. We conclude that AEM functioning could change either through: (1) declines in biomass or loss of seagrass directly due to increased ocean temperatures or increased herbivory from tropicalized herbivores; (2) increased degradation and processing of seagrass detritus within seagrass meadows leading to reduced export; (3) replacement of large temperate seagrass species with smaller tropical seagrass species; and/or (4) loss or changes to macroalgae species in neighboring habitats that export detritus. These processes will alter the amount, composition, quality, timing and frequency of inputs of detritus into ecosystems that rely on AEM as trophic subsidies, which will alter the suitability of AEM as habitat and food for invertebrates.

Detritivore sea cucumbers appear to have been abundant on historic tropical reefs, but (1) have been heavily exploited since at least the mid-1800s, (2) often show minimal recovery post-harvest, and (3) are relatively depleted from modern marine communities. Because they were more abundant, fed on bacteria, microalgae, and other organics, and processed tremendous masses of sediments, removing these detritivores from tropical seas may have suppressed removal of sedimentary pathogens, and impacted co-occurring species in ways that are not documented. We conducted enclosure and exclosure experiments of the sea cucumber Holothuria atra in a back reef lagoon in Moorea, French Polynesia and found that excluding this sea cucumber increased a measure of sediment surface pigmentation by about 10 × but also decreased the potency of extracts from a co-occurring coral (Acropora cytherea) against the heat-activated coral pathogen Vibrio coralliilyticus by a significant 52%. This suggests that the large-scale removal of detritovores from shallow tropical seas may make some co-occurring foundation species more susceptible to pathogens during periods of elevated temperatures or other stresses. [ABSTRACT FROM AUTHOR]

Organisms that rely on detritus as their primary food source may face particularly strong nutritional constraints on growth and development, given the characteristically poor quality of detrital resources. In freshwater ecosystems, the low content of P in detritus often limits detritivore growth. Additionally, a growing body of evidence suggests the biochemical composition of algae, such as essential fatty acids, can limit aquatic detritivore growth. We investigated feeding preference and growth responses of common aquatic detritivores by performing paired feeding-preference and growth experiments on 4 species of larval caddisflies (Trichoptera) from the family Limnephilidae: Asynarchus nigriculus , Anabolia bimaculata , Limnephilus externus , and Ecclisomyia sp. We manipulated both the P content and epiphytic algal biomass of a common detrital food resource (decomposing sedge [ Carex sp.]) by conditioning the detritus under 2 different light (ambient, shaded) and P (ambient [low], +P) regimes. We tested 3 hypotheses that describe feeding preferences and performance under different scenarios of P limitation, algal limitation, and co-limitation by P and algae. We observed evidence of preferential feeding behavior for each of the 4 taxa, with 2 species exhibiting preferences for conditioned detritus with high algal biomass and 2 for detritus from the +P treatments. We observed agreement between feeding preferences and performance (growth, growth efficiency, mortality) for only 2 taxa, with A. nigriculus exhibiting higher growth rates and growth efficiency on their preferred high-P detritus, and L. externus experiencing lower mortality when reared on their preferred high algal biomass detritus. These findings provide an initial step toward characterizing the feeding preferences and performance responses of aquatic detritivores to 2 potentially common nutritional constraints: detrital P and algal supply. [ABSTRACT FROM AUTHOR]

Ecosystems world‐wide experience changes in species composition in response to natural and anthropogenic changes in environmental conditions. Research to date has greatly improved our understanding of how species affect focal ecosystem functions. However, because measurements of multiple ecosystem functions have not been consistently justified for any given trophic group, it is unclear whether interpretations of research syntheses adequately reflect the contributions of consumers to ecosystems. Using model communities assembled in experimental microcosms, we examined the relationship between four numerically dominant detritivore species and six ecosystem functions that underpin fundamental aspects of carbon and nitrogen cycling above‐ and below‐ground. We tested whether ecosystem responses to changes in detritivore identity depended upon species trait dissimilarity, food web compartment (aboveground, belowground, mixed) or number of responses considered (one to six). We found little influence of detritivore species identity on brown (i.e. soil‐based) processes. Only one of four detritivore species uniquely influenced decomposition, and detritivore species did not vary in their influence on soil nitrogen pools (NO3− and NH4+), or root biomass. However, changes in detritivore identity influenced multiple aboveground ecosystem functions. That is, by serving as prey, ecosystem engineers and occasionally also as herbivores as well as detritivores, these species altered the strength of aboveground predator–herbivore interactions and plant–shoot biomass. Yet, dissimilarity of detritivore functional traits was not associated with dissimilarity of ecosystem functioning. These results serve as an important reminder that consumers influence ecosystem processes via multiple energy channels and that food web interactions set important context for consumer‐mediated effects on multiple ecosystem functions. Given that species are being lost, gained and redistributed at unprecedented rates, we can anticipate that changes in species identity will have additional ecosystem consequences beyond those predicted by species' primary functional role. [ABSTRACT FROM AUTHOR]

Changes in the composition of plant functional traits may affect ecosystem processes through influencing trophic interactions. Bottom‐up control by plant species through food availability to animals may vary with time. However, such dynamics and their consequences for deadwood turnover are poorly known for detrital food webs.We introduce a dynamic conceptual model of the feedback of tree functional traits, (deadwood‐feeding) termite populations and deadwood decomposition. We hypothesized that tree functional diversity (in terms of a wood resource economic spectrum [WES]) supports the sustenance of termite populations via complementary food supplied through time, as deadwood varies in traits both initially across species and because of different decomposition rates. Simultaneously, driven by this temporal dynamics of food quality, the consumption of deadwood by termites should hypothetically sustain deadwood turnover in a functionally diverse forest over time.We tested our hypothesis through an 18‐month termite‐exclusion decomposition experiment by incubating coarse (i.e. 5 cm diameter) deadwood of 34 woody species in two subtropical forests in East China. One site still sustained a healthy population of pangolins as the keystone termite predator, whereas another had lost its pangolins due to hunting and illegal wildlife trade.The results supported our hypothesis: in the first 12 months, termites amplified the positive linear relationship between % wood mass loss and initial wood quality (WES). In contrast, between 12 and 18 months, termite‐mediated consumption, and associated wood mass loss, showed a humpback relation with the initial WES. This shift in termite preference of deadwood species along the WES reflects complementary food availability to termites through time.Synthesis. Our findings imply that tree functional composition, with variation in deadwood quality through decomposition time, can help to sustain termite populations and thereby forest carbon turnover. Future studies need to test whether and how our conceptual model may apply to other detrital systems and food webs. In general, food web research would benefit from a stronger focus on temporal patterns for better understanding the interactions of basal resource functional traits and consumers on ecosystem functions. [ABSTRACT FROM AUTHOR]

Gut microbes play an important role in the biology and evolution of insects. Australian native dung beetles (Scarabaeinae) present an opportunity to study gut microbiota in an evolutionary context as they come from two distinct phylogenetic lineages and some species in each lineage have secondarily adapted to alternative or broader diets. In this study, we characterized the hindgut bacterial communities found in 21 species of dung beetles across two lineages, using 16S rRNA sequencing. We found that gut microbial diversity was more dependent on host phylogeny and gut morphology than specific dietary preferences or environment. In particular, gut microbial diversity was highest in the endemic, flightless genus Cephalodesmius, which feeds on a broad range of composted organic matter. The hindgut of Cephalodesmius beetles harbors a highly conserved core set of bacteria, suggesting that the bacteria are symbiotic. Symbiosis is supported by the persistence of the core microbiota across isolated beetle populations and between species in the genus. A coevolutionary relationship is supported by the expansion of the hindgut to form a fermentation chamber and the fermentative nature of the core microbes. In contrast, Australian species of the widespread dung beetle genus Onthophagus that specialize on a single food resource, such as dung or fungus, exhibit minimal food processing behavior and have a short, narrow hindgut and a variable gut microbiota with relatively few core bacterial taxa. A conserved, complex gut microbiota is hypothesized to be unnecessary for this highly mobile genus. [ABSTRACT FROM AUTHOR]

Many organisms contribute to the decomposition of carrion. For arthropods, many studies focus on the necrophagous community, those directly consuming carrion.Necrophagous arthropods use carrion as a shelter or food source. Therefore, carrion generally increases the abundance and biodiversity of necrophagous species. However, it is unclear if carrion has similar effects on detrital communities.This study examines changes in community structure and composition of necrophilous and detrital communities over the course of decomposition.Five pig head carrion were placed at least 7 m apart under cages in temperate mixed forest. Leaf litter was sampled 0 m, 1.5 m, and 3 m from each carrion weekly during summer, and monthly during autumn, until the first frost. Arthropods were extracted from leaf litter by using Berlese funnels.At the carrion site, necrophagous insects increased in abundance, species richness, and Shannon diversity during decomposition, and all decreased after dry decay.Detritus arthropods displayed a sharp increase in abundance during advanced decay, decreasing during dry decay, and a general increase over time for species richness and diversity.In conclusion, carrion can influence the surrounding, non‐necrophagous arthropod community, highlighting the need to investigate carrion effects beyond typical necrophagous species to have a more holistic understanding of carrion ecology. [ABSTRACT FROM AUTHOR]

Background and aims: Intensification of savannah land-use is predicted to negatively influence soil biodiversity and functioning such as litter decomposition by detritivores. Loss of macrodetritivores, particularly termites, may be problematic in drier savannahs due to the capacity of macrodetritivores to sustain litter decomposition. Here we investigate how human land-use and spatiotemporal rainfall influence the contribution of macrodetritivores to plant litter decomposition. Methods: We measured decomposition using globally standardized litter: labile green and recalcitrant rooibos tea litter. The contribution of macrodetritivores to litter decomposition was determined through exclusion using meshed litterbags. Litter decomposition was determined in agricultural land, pastureland and wildlife protected areas during both wet and dry seasons and in mesic and wet rainfall regions across the borders of the Serengeti National Park, Tanzania. Results: Macrodetritivores consumed recalcitrant rooibos and mainly avoided labile green tea litter. On average macrodetritivores enhanced recalcitrant litter decomposition by 22%, but litter mass loss varied across land-uses, typically being higher on agricultural and pastureland compared to wildlife protected areas, and was sustained during periods of water scarcity. However, we observed instances of higher decomposition of recalcitrant litter by macrodetritivores in wildlife protected areas. In contrast, litter decomposition by microbes and microdetritivores was more constrained by seasonal and regional water availability with a minor influence of land-use. Conclusion: We found that moderate human-modification of savannahs is compatible with macrodetritivore litter decomposition. As savannahs become more intensely used by humans, raising ecological awareness among agropastoralist is required to ensure continued contribution of macrodetritivores to litter decomposition. [ABSTRACT FROM AUTHOR]

Copyright of Orinoquia is the property of Universidad de los Llanos and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Converting forest to pasture can alter the roles of biota in ecosystem functioning, while vegetation restoration should arguably assist functional recovery. Since tests of this are scarce, this study quantifies both litter decomposition rates and their association with decomposer invertebrates, across 25 sites representing different phases of deforestation and subsequent reforestation of rain forest. Open and closed (to exclude macro‐invertebrates) mesh bags containing forest leaves were exposed in the field for up to eight months, and invertebrates were extracted from separate collections of ground surface litter. Sites spanned five vegetation categories (five sites in each): reference states of both old‐growth forest and grazed pasture; unassisted woody regrowth aged 20–50 years on former pasture; and assisted regeneration aged 1–3 and 5–10 years after interventions were applied to similar regrowth. Decomposition rates in open bags were about 50% slower in pasture than old‐growth forest, and abundances of macro‐ and meso‐decomposer invertebrates were 95% and 77% lower, respectively. However, in all restoration site‐types, decomposition rates had recovered to 83% of old‐growth values, and abundances of invertebrate decomposers were similar in old‐growth forest. Decomposer community composition at a broad taxonomic level differed strongly between pasture and all other vegetation types. Exclusion of macro‐invertebrates decreased decomposition rates by only about 3.1%, but decomposition rates in open bags were significantly correlated (across sites) with abundances of both macro‐ and meso‐decomposers, most strongly so for meso‐decomposers. Drawing useful generalizations across studies is impeded by differing methodologies and because few include both agricultural and forest reference sites. [ABSTRACT FROM AUTHOR]

In different parts of the world, the increasing agricultural practice of retaining crop stubble in fields across seasons has led to population increases of soil-dwelling arthropods, primarily detritivorous species. These species typically play a beneficial role in the ecosystem, but some, including the Portuguese millipede (Ommatoiulus moreleti (Lucas)) can be sporadic pests. To assist in better understanding of pest risk, this study examines why O. moreleti feeds on crop seedlings. For lupin, seedling susceptibility appears to be related to plant properties, with greatly different levels of damage caused to the two cultivated species (Lupinus angustinus and Lupinus albus) and particularly between cultivated and wild-type L. angustinus seedlings. Millipedes feeding on lupin (cultivated L. angustinus), but not lucerne (Medicago sativa), gained a similar amount of weight to those feeding on other foods known to be readily consumed. The life-stage and sex of O. moreleti was found to be related to seedling damage. The presence of crop stubbles (as alternate food sources) did not limit the damage O. moreleti caused to lupin, suggesting that the presence of stubble in a field situation may not preclude feeding on crop seedlings. We discuss how results from these controlled environment trials can build a basis for understanding variable crop damage by O. moreleti in the field. [ABSTRACT FROM AUTHOR]

To explore the mixing effect of litter decomposition and the role of detritivores, we conducted a laboratory-based microcosm experiment to study the influence of detritivores on litter mixture decomposition by using two litter species with contrasting quality, i.e ., Cinnamomum camphora and Michelia × alba , and a detritivore (isopoda). After 100 days incubation, the decomposition rate of litter mixture was 52.1%, slower than that of M. alba (62.6%) and significantly faster than that of C. camphora (33.6%). The addition of isopods significantly increased litter decomposition rate, with C. camphora , M. alba , and the mixture increased by 14.4%, 20.1% and 22.1%, respectively. There was no significant mixing effect without isopods. Adding isopods significantly promoted the mixing effect of litter decomposition, with a value of the litter mixture decomposition effect of 8.6%. The detritivores increased litter decomposition rate and mixing effect through increasing consumption of litter with better quality.

Invasions can trigger cascades in ecological communities by altering species interactions. Following the introduction of cats and foxes into Australia, one tenth of Australia's terrestrial mammal species became extinct, due to predation, while many continue to decline. The broader consequences for Australian ecosystems are poorly understood. Soil-dwelling invertebrates are likely to be affected by the loss of fossorial native mammals, which are predators and disturbance agents. Using reintroductions as a model for ecosystems prior to species loss, we tested the hypothesis that mammal reintroduction leads to reduced vegetation cover and altered termite assemblages, including declines in abundance and biomass and changed species composition. We hypothesised that the magnitude of mammal reintroduction effects would diminish with increasing aridity, which affects resource availability. We compared six paired sites inside and outside three reintroduction sanctuaries across an aridity gradient. We sampled termite assemblages using soil trenches and measured habitat availability. Reintroductions were associated with increased bare ground and reduced vegetation, compared with controls. Aridity also had an underlying influence on vegetation cover by limiting water availability. Termite abundance and biomass were lower where mammals were reintroduced and the magnitude of this effect decreased with increasing aridity. Termite abundance was highest under wood, and soil-nesting wood-feeders were most affected inside sanctuaries. Ecological cascades resulting from exotic predator invasions are thus likely to have increased termite biomass and altered termite assemblages, but impacts may be lower in less-productive habitats. Our findings have implications for reserve carrying capacities and understanding of assemblage reconstruction following ecological cascades. [ABSTRACT FROM AUTHOR]

Increasing climate variability is one of the dominant components of climate change, resulting particularly in altered rainfall patterns. Yet, the consequences of rainfall variability on biogeochemical processes that contribute to greenhouse gas emissions has received far less attention than have changes in long-term mean rainfall. In particular, it remains unclear how leaf litter decomposition responds to changes in rainfall frequency compared to changes in cumulative rainfall quantity, and if changes in rainfall patterns will differentially affect organisms in the decomposer food web (e.g., microbial decomposers that break down leaf litter through saprotrophic processes versus detritivores that directly ingest leaf litter). To address this knowledge gap, we disentangled the relative importance of cumulative rainfall quantity and rainfall frequency on both microbial- and detritivore-driven litter decomposition, using the isopod Armadillidium vulgare as a model macro-detritivore species and simulating rainfall in a full-factorial microcosm experiment. We found that microbially-driven decomposition was positively related to cumulative rainfall quantity, but tended to saturate with increasing cumulative rainfall quantity when rainfall events were large and infrequent. This saturation appeared to result from two mechanisms. First, at high level of cumulative rainfall quantity, large and infrequent rainfall events induce lower litter moisture compared to smaller but more frequent ones. Second, microbial activity saturated with increasing litter moisture, suggesting that water was no longer limiting. In contrast, isopod-driven decomposition was unaffected by cumulative rainfall quantity, but was strongly controlled by the rainfall frequency, with higher isopod-driven decomposition at low rainfall frequency. We found that isopod-driven decomposition responded positively to an increase in the weekly range of soil moisture and not to mean soil or litter moisture, suggesting that an alternation of dry and moist conditions enhances detritivore activity. Collectively, our results suggest that A. vulgare morphological and behavioral characteristics may reduce its sensitivity to varying moisture conditions relative to microbial decomposers. We conclude that the activity of microorganisms and isopods are controlled by distinct aspects of rainfall patterns. Consequently, altered rainfall patterns may change the relative contribution of microbial decomposers and detritivores to litter decomposition. • We disentangled the effect of rainfall quantity from frequency on decomposition. • We compared the responses of microbially- and isopod-driven litter decomposition. • Microbially-driven decomposition increased with increasing rainfall quantity. • Isopod-driven decomposition increased with decreasing rainfall frequency. [ABSTRACT FROM AUTHOR]

Lampreys have a complex life cycle which includes a multi‐year infaunal larval stage (ammocoete). Gut content analysis has generally identified detritus (i.e., unidentifiable organic matter) as the major dietary component to ammocoetes, though algae can also be important. However, gut content preserves only a snapshot of the animal's diet and does not reflect assimilated material. In order to better characterise the nutritional sources supporting ammocoete growth, we analysed ammocoete body tissue and potential dietary sources at two streams using natural Δ14C and δ15N to estimate time‐integrated nutritional support. Bayesian isotope mixing models revealed differences in the importance of sources supporting ammocoetes between sites. Ammocoetes from a stream in a mixed land usage area (~50% agriculture, ~40% forest and ~10% developed) were primarily supported (mean: ~50%) by fresh terrestrial organic matter but were also supported by substantial contributions (mean: ~30%) by aged organic matter (AOM) and autochthonous material (algae; mean ~20%). In a predominantly forested (~90%) headwater stream, different modelling scenarios (uninformed or informed priors) suggested that algal support of ammocoete nutrition ranged from 7% to 45%. However, the model relying on informed priors developed from gut content analysis produced the low estimates, suggesting these were more reliable. When algae were a minor component of the nutrition at the forested site, ammocoetes were highly dependent on AOM (83 ± 26%; mean ± SD). Based on these findings, ammocoete growth and development are predicted to be strongly influenced by both land use and the availability of allochthonous and autochthonous materials of varying ages within streams. [ABSTRACT FROM AUTHOR]

Abstract Aquaculture of larval lampreys (ammocoetes), to help recover and maintain threatened populations, is increasingly viewed as an important management tool. Ammocoetes are filter-feeders that remain burrowed in fine grain substrates for the majority of their lives, making it difficult to determine how well diets are being supplied and in what proportions various foods are utilized. Stable isotope analysis offers the ability to distinguish which foods are being incorporated into animal biomass. While muscle tissue is most commonly used for stable isotope analysis, other tissues could also be collected to avoid lethal sampling (e.g., blood) or to provide insight into condition (e.g., liver). Muscle, red blood cells (RBC), plasma, liver, and notochord were collected from Pacific lamprey (Entosphenus tridentatus) larvae raised in the laboratory on a varied diet; δ2H, δ13C, δ15N, δ18O and δ34S were measured in food sources, animal tissues, and lipid-extracted muscle. Tissues were generally isotopically similar to one another except in a few notable cases. The δ2H of notochord was more enriched than any other tissue and the δ15N and δ34S of RBC were elevated over muscle. The δ18O of all tissues was predicted from source water, allowing this isotope ratio to provide information about regional origin of lampreys. A stable isotope mixing model found that larval biomass, even when ammocoetes were supplied with various diet items, was still primarily dependent on aquatic sediments. Therefore, the burrowing medium supplied to ammocoetes in aquaculture facilities is likely to have a strong impact on growth rate and may benefit from the inclusion of more labile organic material or feed that specifically enriches the aquatic sediment. Highlights • It is difficult to detect if larval lampreys reared in aquaculture are utilizing food sources, but stable isotope analysis can identify nutritional sources. • Larval lampreys are highly dependent on aquatic sediments even when fed varied diets. • Removal of lipids from ammocoete tissues is critical before stable isotope analysis. • Stable isotopes in various tissues showed tissues are similar. [ABSTRACT FROM AUTHOR]

Abstract Soil dwelling beetles contribute greatly to biodiversity and offer important services in agroecosystems including predation, weed herbivory and decomposition. An experiment was conducted in the 2013/2014 and 2014/2015 cropping seasons at Chinhoyi University of Technology experiment station, Zimbabwe, to investigate the impact of tillage system (conservation tillage and conventional tillage), fertilizer application rate and weeding intensity on beetle communities in maize. The experiment was laid out in a split-split plot using a randomized complete block design and replicated three times. Beetles were sampled using un-baited pitfall traps. A total of 6020 beetles were collected comprising 53 species, nine families and four functional groups. Tillage system had the strongest effects on beetle diversity. Advanced constrained analysis using principal response curves revealed that the abundances of Anchophthalmus oncotipes decreased under conservation tillage. In contrast, abundances of Zophosis boei , Gonocephalum simplex , Renatiella reticulata and Stenethmus tentyriniformis increased under conservation tillage relative to conventiona tillage (CT). Detritivore abundances were 50.8% and 45% greater under rip line seeding than CT during the hot dry season of 2014 and cold dry season of 2015, respectively. Predator abundances were almost double in basin planting relative to CT during the cold dry season of 2014 and hot humid season of 2015. In the 2014/2015 cropping season, maize grain yield significantly increased (P < 0.05) from 4963 kg ha−1 in CT to 7848 kg ha−1 in basin planting tillage. Application of a high rate of fertilizer increased maize grain yield by 31.2% compared to the low and medium fertilizer application rates. Weeding twice resulted in the highest maize grain yield but there was no yield benefit in increasing weeding intensity more than twice per season. Our results suggest that there is potential for increasing density and diversity of beneficial beetle species through conservation tillage with crop residue retention. [ABSTRACT FROM AUTHOR]

Highlights • Severely burnt sites supported fewer invertebrates and lower invertebrate diversity. • Invertebrates in severely burnt sites were larger. • Other traits were not clearly associated with fire severity. Abstract High severity fires are likely to become more prevalent with global climate change, so it is critical that we understand their effects on forest ecosystems. Leaf litter dependent fauna are likely to be particularly vulnerable to habitat loss resulting from fire, which often destroys their leaf litter habitat. We hypothesised that, as fire severity increased: (1) richness and abundance of macroinvertebrate litter fauna would decline; (2) species composition would change; and (3) species responses would depend on morphological and trophic traits, with proportions of larger, winged and predatory species increasing with fire severity. To test the effects of fire severity on the composition and functional traits of litter-dwelling macroinvertebrates, we collected macroinvertebrates using litterbags and standardised hand searches of logs at unburnt, low severity (ground burnt) and high severity (crown burnt) burnt eucalyptus forests (n = 7) in south eastern Australia, three years after fire. Litter-dwelling macroinvertebrates were larger, less abundant and less species-rich at high severity burnt than unburnt sites and species composition differed from unburnt and low severity burnt sites. Fire severity did not affect the proportion of winged species or individuals. Thus, we suggest small bodied species may struggle to recolonize through limited dispersal ability or may be limited by the drier post-fire environment. Increases in large scale, high severity fires may therefore result in assemblages dominated by larger macroinvertebrate species, but will also be associated with lower species richness. [ABSTRACT FROM AUTHOR]

1. Bird nests are ubiquitous but patchy resources in many terrestrial habitats. Nests can support diverse communities of commensal invertebrates, especially moths (Lepidoptera). However, there is a shortage of information on the moths associated with bird nests, and the factors influencing their abundance, diversity and composition. 2. Two hundred and twenty‐four nests, from 16 bird species, were sampled from sites in mid‐Wales (UK) and the moths that emerged from them were recorded. 3. Seventy eight percent of nests produced moths, with 4657 individuals of ten species recorded. Moth communities were dominated by generalist species rather than bird nest specialists. 4. Open nests built in undergrowth supported significantly fewer moths than nests in enclosed spaces (for example, nesting boxes). The occurrence of fleas was positively associated with the incidence and abundance of moths. There was no evidence that different nest types supported different moth communities. Bird nests are concentrated pockets of resource for detritivores and can support diverse communities of invertebrates, especially moths (Lepidoptera).Seventy eight percent of the 224 nests collected produced moths, with 4657 adults from ten species recorded. Generalist detritivores greatly outnumbered bird nest obligates.Nest boxes support a larger abundance of moths than open nests and the occurrence of fleas was positively associated with the presence of moths. [ABSTRACT FROM AUTHOR]

Highlights • The woodlouse Porcellio dilatatus was used in food preference tests. • Cork-oak and a grass species litter from farms with different management was used. • Management is a strong determinant of litter consumption for the oak species. • Management effects on litter intake vary with plant species and fungal colonization. Abstract The detritivore woodlouse Porcellio dilatatus was selected to test the effects of home-field advantage and land management on the isopod feeding preferences and ingestion rates. Woodlice specimens and plant litter from two neighbouring farms were used in "cafeteria" experiments. The farms are cork-oak agro-forests with a similar litter matrix but different land-use history and current management (organic vs. conventional farms). The plant litter species selected were Quercus suber L. and Agrostis pouretti L. Leaf litter lignin, N and C concentrations, total phenolics, and fungal biomass were measured on both litter species for the assessment of litter quality. A higher preference for cork-oak litter from the conventional site was observed, both in isopods collected from the organic farm and from the conventional farm. This can be explained by the significant differences in litter quality that were found between Quercus litter types collected in the two farms. The differences in the nutritional content (lower C:N ratio for Quercus of the conventional farm) of litter from the same plant species support the assumption of a management effect on decomposition by changing plant litter quality. Yet, this pattern was not found for the other plant litter tested in this study – the grass species Agrostis pouretti. Also, despite the remarkable differences in litter traits between Quercus and Agrostis , no significant differences were found between the ingestion rates of the litter from the two plant species. Although, depending on the plant species, litter quality resulting from different management influenced P. dilatatus feeding preferences and ingestion rates. [ABSTRACT FROM AUTHOR]