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Neotropical black mangrove (Avicennia germinans) is expanding poleward into temperate salt marsh along Atlantic Florida, USA, with field evidence of trait shifts consistent with greater cold tolerance within range margin populations. However, whether these shifts have a genetic basis remains unanswered. To address this gap, we measured multiple phenotypic traits of twenty A. germinans maternal cohorts from areas in both the Atlantic Florida range core and margin in a 2-year greenhouse common garden with annual temperatures analogous to range margin conditions. Compared to those from the range core, range margin cohorts survived in greater numbers, established (i.e., produced first true leaves) more quickly, and were less stressed under winter temperatures. Range margin cohorts were not taller, but invested more into lateral growth and biomass accumulation that presumably reflects adaptation to their colder and open-canopy environment. Range margin cohorts also exhibited leaf traits consistent with greater resource acquisition that may compensate for a shorter growing season and reduced light quality at higher latitude. Our results suggest that genetically based phenotypic differences better enable these range margin mangroves to thrive within their stressful environment and may facilitate further poleward expansion. An improved understanding of adaptive trait variation within ecologically important mangrove foundation species should also help inform coastal restoration initiatives.

Amongst the global decline of coral reefs, hope spots such as Cordelia Bank in Honduras, have been identified. This site contains dense, remnant thickets of the endangered species Acropora cervicornis, which local managers and conservation organizations view as a potential source population for coral restoration projects. The aim of this study was to determine the genetic diversity of colonies across three banks within the protected area. We identified low genetic diversity (FST = 0.02) across the three banks, and genetic similarity of colonies ranged from 91.3 to 95.8% between the banks. Clonality rates were approximately 30% across the three banks, however, each genotype identified was unique to each bank. Despite the low genetic diversity, subtle genetic differences within and among banks were demonstrated, and these dense thickets were shown not to be comprised of a single or a few genotypes. The presence of multiple genotypes suggests A. cervicornis colonies from these banks could be used to maintain and enhance genetic diversity in restoration projects. Management of hope spots, such as Cordelia Bank, and the incorporation of genetic information into restoration projects to ensure genetic diversity within out-planted populations, will be critical in the ongoing challenge of conserving and preserving coral reefs.

Como primer paso para establecer la estructura genética del erizo de mar Echinometra lucunter lucunter a lo largo del Caribe, se aislaron 26 microsatélites usando secuenciación de extremo pareado (Next Generation Sequencing, NGS) Illumina. Se optimizaron exitosamente 17 marcadores y se probó su variación alélica en 23 individuos recolectados a lo largo del mar Caribe y en Cabo Verde, Atlántico oriental tropical. El número de alelos por locus (Na) fluctuó entre cuatro y 24, la heterocigosidad observada (Ho) entre 0,682 y 1 y la heterocigosidad esperada (He), entre 0,609 y 0,9304. No hubo desequilibrio de ligamento entre los pares de locus detectados. Los microsatelites aislados e identificados se usarán por primera vez para detectar la influencia de las barreras marinas en el flujo génico del erizo E. lucunter lucunter a lo largo del mar Caribe. Estos nuevos marcadores serán esenciales para la conservación y los estudios de conectividad a través del mar Caribe y el océano Atlántico, área donde se distribuye la especie. As a first step to establish the genetic structure of the sea urchin Echinometra lucunter lucunter throughout the Caribbean Sea, 26 microsatellite loci were isolated using Illumina paired-end sequencing, Next Generation Sequencing (NGS). We successfully optimized 17 loci for genotyping and the variation tested for 23 individuals from the Caribbean Sea and Tropical Eastern Atlantic Ocean. The allele number per locus (Na) ranged from four to 24, the observed heterozygosity (Ho) from 0.682 to 1, and the expected heterozygosity (He) from 0.609 to 0.9304. We detected no linkage disequilibrium between pairs of loci. These microsatellites will be used for the first time to detect the influence of marine barriers to genetic flow in the sea urchin E. lucunter lucunter throughout the Caribbean Sea. These new validated markers will be essential for current conservation and connectivity studies across the Caribbean Sea and the Atlantic Ocean.

Understanding population genetic structure can help us to infer dispersal patterns, predict population resilience and design effective management strategies. For sessile species with limited dispersal, this is especially pertinent because genetic diversity and connectivity are key aspects of their resilience to environmental stressors. Here, we describe the population structure of Ircinia campana, a common Caribbean sponge subject to mass mortalities and disease. Microsatellites were used to genotype 440 individuals from 19 sites throughout the Greater Caribbean. We found strong genetic structure across the region, and significant isolation by distance across the Lesser Antilles, highlighting the influence of limited larval dispersal. We also observed spatial genetic structure patterns congruent with oceanography. This includes evidence of connectivity between sponges in the Florida Keys and the southeast coast of the United States (>700 km away) where the oceanographic environment is dominated by the strong Florida Current. Conversely, the population in southern Belize was strongly differentiated from all other sites, consistent with the presence of dispersal-limiting oceanographic features, including the Gulf of Honduras gyre. At smaller spatial scales (

The fire salamander (Salamandra salamandra and its relatives) is of increasing priority for ex situ conservation due to the spread of the fungal pathogen Batrachochytrium salamandrivorans in Europe. In captivity, the species may be maintained on a clinical paper-based or a naturalistic substrate, either of which has its own advantages and disadvantages. However, the impact of these two substrates on bacterial microbiotas within an enclosure and on the salamanders themselves is unknown. To investigate this, we maintained captive fire salamanders on either paper towels or a naturalistic substrate and quantified the culturable microbiotas of both substrates across the one-week lifespan of a paper towel and of the salamanders themselves over a six-month period. We found significant differences in the bacterial communities associated with the two substrates. Over a week-long period, there were major fluctuations in the community composition and abundance on paper towels while on the naturalistic substrate bacterial communities were relatively stable. The skin microbiota of salamanders were indistinguishable at the beginning of the study but after six months differed significantly between the two treatments, although the bacterial morphotypes present remained relatively similar compared with changes between substrates. These data show that husbandry protocols may have a strong influence on the culturable bacterial communities to which captive amphibians are exposed. Nevertheless, the animals were apparently able to maintain their own microbiota to a considerable degree. These findings should be borne in mind when determining husbandry protocols. Given the relative benefits of both types of enclosure, it is possible that a hybrid approach could be used whereby a small amount of naturalistic substrate is provided in a container within an otherwise clinical enclosure, to act as a bacterial reservoir.

Premise Host-plant genetic variation can shape associated communities of organisms. These community-genetic effects include (1) genetically similar hosts harboring similar associated communities (i.e., the genetic similarity rule) and (2) host-plant heterozygosity increasing associated community diversity. Community-genetic effects are predicted to be less prominent in plant systems with limited genetic variation, such as those at distributional range limits. Yet, empirical evidence from such systems is limited. Methods We sampled a natural population of a mangrove foundation species (Avicennia germinans) at an expanding range limit in Florida, USA. We measured genetic variation within and among 40 host trees with 24 nuclear microsatellite loci and characterized their foliar endophytic fungal communities with internal transcribed spacer (ITS1) gene amplicon sequencing. We evaluated relationships among host-tree genetic variation, host-tree spatial location, and the associated fungal communities. Results Genetic diversity was low across all host trees (mean: 2.6 alleles per locus) and associated fungal communities were relatively homogeneous (five sequence variants represented 78% of all reads). We found (1) genetically similar host trees harbored similar fungal communities, with no detectable effect of interhost geographic distance. (2) Host-tree heterozygosity had no detectable effect, while host-tree absolute spatial location affected community alpha diversity. Conclusions This research supports the genetic similarity rule within a range limit population and helps broaden the current scope of community genetics theory by demonstrating that community-genetic effects can occur even at expanding distributional limits where host-plant genetic variation may be limited. Our findings also provide the first documentation of community-genetic effects in a natural mangrove system.

The congeneric lagomorphs Lepus timidus and L. europaeus share allopatric distributions in many areas of Europe characterised by competitive exclusion and hybridisation. We investigated prospects for these species under climate change in northern England uplands. We created ensemble models predicting niche realisation for these species, influenced by abiotic and biotic factors, estimating niche overlap in geo-environmental space. The two species occupy distinctly different niches, influenced more by vegetation preferences than climatic differences. The current climate niche for L. timidus featured higher elevations with cooler temperatures and 168 km2 range extent. Its current habitat niche scale was larger at 269 km2, comprised entirely of upland dwarf shrubs: heather, cotton grass, moorland grasses. By contrast, the current climate niche predicted L. europaeus occupying lowland areas with a milder climate and range extent of 252 km2. Its current habitat niche was also greater, 401 km2, being mostly improved grassland. Competition was presently limited. The current niche predictions showed very little geographic overlap between the species. Niche overlap measured by Schoener Index was low: current climate niche 0.16; current habitat niche 0.07. The future climate niches for 2050 (IPCC RCP2.6), predicted L. timidus range contracting to 19 km2, on hilltops and L. europaeus range expanding to 765 km2. Consequently L. timidus range would be wholly within the L. europaeus range. In many contact zones throughout Europe, L. europaeus outcompetes L. timidus; however, in the Peak District their distributions are largely distinct. Future replacement of L. timidus by L. europaeus may be engendered by dietary convergence, should a warmer climate cause a transition of upland dwarf shrub vegetation to grasses.

This study wasconducted to determine how the litter quality and decomposition of nine species (Acacia auriculiformis, Albizia zygia, Azadiractha indica,Baphia nitida, Gliricidia sepium, Leucaena leucocephala, Tithonia diversifolia, Senna spectabilis and Zea mays) influence soil N availability, microbial biomass and β-glucosidase activity during soil fertility improvement. The results on plant residue chemistry showed significant differences among species with N concentration ranging from 12.2 g kg−1 in Z. mays to 39.2 g kg−1 in B. nitida.C/N ratio was greatest in Z. mays (34.4) while lignin and polyphenol concentrations were greatest in A. auriculiformis. The highest decomposition rate (0.251% day−1) occurred in T. diversifolia and least in A. auriculiformis, A. zygia, B. nitida and Z. mays with half-lives of between 28 – 56 days. Similar to the results on decomposition, between 80 to 89% of N, P, K, Ca and Mg were released from T. diversifolia within 7 days compared with more than 70% retention in A. auriculiformis, B. nitida and Z. mays. Moreover, the half-lives of decomposition and nutrient release of G. sepium, L. leucocephala, A. indica and S. spectabiliswere within 14 days. Mineral N, soil microbial biomass and β-glucosidase activities increased in all treatments with T. diversifolia recording the greatest effect. While N mineralization occurred in all species throughout the experiment, an initial N immobilization was recorded in A. zygia, B. nitida, A. auriculiformis and Z. mays treatments for up to 14 days. Further, the results showed the decomposition, nutrient release rates, mineral N, soil microbial biomass and β-glucosidase activities were dependent on litter quality. Phosphorus, lignin, lignin/N ratio and (lignin + polyphenol)/N ratio were most influential based on significant (p = 0.05) results.

Marine sponges are hosts to large, diverse communities of microorganisms. These microbiomes are distinct among sponge species and from seawater bacterial communities, indicating a key role of host identity in shaping its resident microbial community. However, the factors governing intraspecific microbiome variability are underexplored and may shed light on the evolutionary and ecological relationships between host and microbiome.Here, we examined the influence of genetic variation and geographic location on the composition of the Ircinia campana microbiome.We developed new microsatellite markers to genotype I. campana from two locations in the Florida Keys, USA, and characterized their microbiomes using V4 16S rRNA amplicon sequencing.We show that microbial community composition and diversity is influenced by host genotype, with more genetically similar sponges hosting more similar microbial communities. We also found that although I. campana was not genetically differentiated between sites, microbiome composition differed by location.Our results demonstrate that both host genetics and geography influence the composition of the sponge microbiome. Host genotypic influence on microbiome composition may be due to stable vertical transmission of the microbial community from parent to offspring, making microbiomes more similar by descent. Alternatively, sponge genotypic variation may reflect variation in functional traits that influence the acquisition of environmental microbes. This study reveals drivers of microbiome variation within and among locations, and shows the importance of intraspecific variability in mediating eco‐evolutionary dynamics of host‐associated microbiomes., For the first time, the authors show that intraspecific genetic variation affects microbiome composition in a marine sponge (Ircinia campana), with positive correlations observed between genetic and microbiome similarity. This has significant implications for our understanding of the ecological and evolutionary relationships between host and microbiome in this important model system.

Many species are expanding beyond their distributional range margins in response to a warming planet. Due to marginal environmental conditions and novel selection pressures, range margins may foster unique genetic adaptations that can better enable species to thrive under the extreme climatic conditions at and beyond their current distributional limits. Neotropical black mangrove (Avicennia germinans) is expanding poleward into temperate salt marsh along Atlantic Florida, USA, with field evidence of adaptive trait shifts within range-margin A. germinans populations. However, whether these adaptive shifts have a genetic basis remains to be answered.We monitored twenty A. germinans maternal cohorts from areas in both the Atlantic Florida range core and margin in a greenhouse common garden with annual temperatures analogous to range-margin conditions. We measured variation in a series of phenotypic traits starting at initial planting of field-collected propagules and continuing until two years development.Maternal cohorts from the Atlantic Florida range margin consistently outperformed those from the range core throughout the experiment. Range-margin cohorts survived in greater numbers, established faster, and were less stressed under winter chilling and sub-zero temperatures that are often reached at the Atlantic range margin, but not within the range core. Range-margin cohorts did not grow taller, but instead invested more into lateral growth and biomass accumulation that presumably reflects adaptation to their colder and open canopy environment. Range-margin cohorts also exhibited leaf traits consistent with greater resource acquisition that may compensate for a shorter growing season and reduced light quality at higher latitude.Synthesis. We confirmed that there is a genetic basis to adaptive trait shifts towards an expanding mangrove range margin. Our results suggest that genetically-based phenotypic differences better enable these range-margin mangroves to thrive within their stressful environment and may facilitate further poleward expansion in the future. In addition, our documentation of adaptive trait variation among maternal cohorts of an ecologically-important mangrove foundation species, quantitative data that is lacking for mangroves, should help inform mangrove restoration initiatives.

Environmental degradation has the potential to alter key mutualisms that underlie the structure and function of ecological communities. How microbial communities associated with fishes vary across populations and in relation to habitat characteristics remains largely unknown despite their fundamental roles in host nutrition and immunity. We find significant differences in the gut microbiome composition of a facultative coral-feeding butterflyfish (Chaetodon capistratus) across Caribbean reefs that differ markedly in live coral cover (∼0-30%). Fish gut microbiomes were significantly more variable at degraded reefs, a pattern driven by changes in the relative abundance of the most common taxa potentially associated with stress. We also demonstrate that fish gut microbiomes on severely degraded reefs have a lower abundance of Endozoicomonas and a higher diversity of anaerobic fermentative bacteria, which may suggest a less coral dominated diet. The observed shifts in fish gut bacterial communities across the habitat gradient extend to a small set of potentially beneficial host associated bacteria (i.e., the core microbiome) suggesting essential fish-microbiome interactions may be vulnerable to severe coral degradation.

Surveying cryptic, nocturnal animals is logistically challenging. Consequently, density estimates may be imprecise and uncertain. Survey innovations mitigate ecological and observational difficulties contributing to estimation variance. Thus, comparisons of survey techniques are critical to evaluate estimates of abundance. We simultaneously compared three methods for observing mountain hare Lepus timidus using Distance sampling to estimate abundance. Daylight visual surveys achieved 41 detections, estimating density at 14.3 hares km–2 (95%CI 6.3–32.5) resulting in the lowest estimate and widest confidence interval. Night-time thermal imaging achieved 206 detections, estimating density at 12.1 hares km–2 (95%CI 7.6–19.4). Thermal imaging captured more observations at furthest distances, and detected larger group sizes. Camera traps achieved 3705 night-time detections, estimating density at 22.6 hares km–2 (95%CI 17.1–29.9). Between the methods, detections were spatially correlated, although the estimates of density varied. Our results suggest that daylight visual surveys tended to underestimate density, failing to reflect nocturnal activity. Thermal imaging captured nocturnal activity, providing a higher detection rate, but required fine weather. Camera traps captured nocturnal activity, and operated 24/7 throughout harsh weather, but needed careful consideration of empirical assumptions. We discuss the merits and limitations of each method with respect to the estimation of population density in the field.

This review represents a comprehensive analysis on pollutants in elasmobranchs including meta-analysis on the most studied pollutants: mercury, cadmium, PCBs and DDTs, in muscle and liver tissue. Elasmobranchs are particularly vulnerable to pollutant exposure which may pose a risk to the organism as well as humans that consume elasmobranch products. The highest concentrations of pollutants were found in sharks occupying top trophic levels (Carcharhiniformes and Lamniformes). A human health risk assessment identified that children and adults consuming shark once a week are exposed to over three times more mercury than is recommended by the US EPA. This poses a risk to local fishing communities and international consumers of shark-based products, as well as those subject to the widespread mislabelling of elasmobranch products. Wider screening studies are recommended to determine the risk to elasmobranchs from emerging pollutants and more robust studies are recommended to assess the risks to human health.

Interactions between hosts and their resident microbial communities are a fundamental component of fitness for both agents. Though recent research has highlighted the importance of interactions between animals and their bacterial communities, comparative evidence for fungi is lacking, especially in natural populations. Using data from 49 species, we present novel evidence of strong covariation between fungal and bacterial communities across the host phylogeny, indicative of recruitment by hosts for specific suites of microbes. Using co-occurrence networks, we demonstrate that fungi form critical components of putative microbial interaction networks, where the strength and frequency of interactions varies with host taxonomy. Host phylogeny drives differences in overall richness of bacterial and fungal communities, but the effect of diet on richness was only evident in mammals and for the bacterial microbiome. Collectively these data indicate fungal microbiomes may play a key role in host fitness and suggest an urgent need to study multiple agents of the animal microbiome to accurately determine the strength and ecological significance of host-microbe interactions.SIGNIFICANCE STATEMENTMicrobes perform vital metabolic functions that shape the physiology of their hosts. However, almost all research to date in wild animals has focused exclusively on the bacterial microbiota, to the exclusion of other microbial groups. Although likely to be critical components of the host microbiome, we have limited knowledge of the drivers of fungal composition across host species. Here we show that fungal community composition is determined by host species identity and phylogeny, and that fungi form extensive interaction networks with bacteria in the microbiome of a diverse range of animal species. This highlights the importance of microbial interactions as mediators of microbiome-health relationships in the wild.

Expansion of many tree species lags behind climate‐change projections. Extreme storms can rapidly overcome this lag, especially for coastal species, but how will storm‐driven expansion shape intraspecific genetic variation? Do storms provide recruits only from the nearest sources, or from more distant sources? Answers to these questions have ecological and evolutionary implications, but empirical evidence is absent from the literature. In 2017, Hurricane Irma provided an opportunity to address this knowledge gap at the northern range limit of the neotropical black mangrove (Avicennia germinans ) on the Atlantic coast of Florida, USA. We observed massive post‐hurricane increases in beach‐stranded A. germinans propagules at, and past, this species’ present‐day range margin when compared to a previously‐surveyed, non‐hurricane year. Yet, propagule dispersal does not guarantee subsequent establishment and reproductive success (i.e., effective dispersal). We also evaluated prior effective dispersal along this coastline with isolated A. germinans trees identified beyond the most northern established population. We used 12 nuclear microsatellite loci to genotype 896 hurricane‐driven drift propagules from nine sites and 10 isolated trees from four sites, determined their sources of origin, and estimated dispersal distances. Almost all drift propagules and all isolated trees came from the nearest sources. This research suggests that hurricanes are a prerequisite for poleward range expansion of a coastal tree species and that storms can shape the expanding gene pool by providing almost exclusively range‐margin genotypes. These insights and empirical estimates of hurricane‐driven dispersal distances should improve our ability to forecast distributional shifts of coastal species.

Better-informed mangrove conservation and management practices are needed as the ecosystem services provided by these intertidal forests continue to be threatened by increasing anthropogenic pressures and climate change. Multiple layers of knowledge are required to achieve this goal, including insights into population genetics of mangrove species. Understanding the importance of population-genetic insights to conservation, multiple research groups have developed microsatellite loci for the widespread, neotropical red mangrove, Rhizophora mangle. However, although a wealth of genetic markers exist, empirical research is limited in the number of these loci employed. Here, we designed two multiplex PCR panels that combine seven novel loci developed for this work and eight previously-developed loci from three research groups to generate 15-locus genotypes, more than twice the average number of loci used in previous research, in only two PCR. We demonstrated utility in R. mangle from four sites across ~ 2500 km near this species’ northern latitudinal limits, and that these multiplex panels were better able to delineate populations than data subsets with numbers of loci comparable to previous research. We focus our discussion on how this tool is a more-informative, efficient (both in terms of time and resources), and easily-modifiable alternative to address many pressing conservation and management issues, such as the generation of baseline genetic data for areas not yet studied, better defining management units, and monitoring genetic effects of restoration projects. We also provide a quick protocol that outlines each step in this procedure to facilitate the use of this tool by others.

Genetic tools can have a key role in informing conservation management of declining populations. Genetic diversity is an important determinant of population fitness and resilience, and can require careful management to ensure sufficient variation is present. In addition, population genetics data reveal patterns of connectivity and gene flow between locations, enabling mangers to predict recovery and resilience, identify areas of local adaptation, and generate restoration plans. Here, we demonstrate a conservation genetics approach to inform restoration and management of the loggerhead sponge (Spheciospongia vesparium) in the Florida Keys, USA. This species is a dominant, habitat-forming component of marine ecosystems in the Caribbean region, but in Florida has suffered numerous mass mortality events. We developed microsatellite markers and used them to genotype sponges from 14 locations in Florida and a site each in The Bahamas, Belize and Barbuda. We found that genetic diversity levels were similar across all sites, but inbreeding and bottleneck signatures were present in Florida. Populations are highly structured at the regional scale, whilst within Florida connectivity is present in a weak isolation by distance pattern, coupled with chaotic genetic patchiness. Evidence of a weak barrier to gene flow was found in Florida among sites situated on opposite sides of the islands in the Middle Keys. Loggerhead sponge populations in Florida are vulnerable in the face of mass mortalities due to low connectivity with other areas in the region, as well as distance-limited and unpredictable local connectivity patterns. However, our discovery of Florida’s high genetic diversity increases hope for resilience to future perturbations. These results provide valuable insight for sponge restoration practice in Florida.

The central-marginal hypothesis (CMH) posits that range margins exhibit less genetic diversity 16 and greater inter-population genetic differentiation compared to range cores. CMH predictions 17 are based on long-held ‘abundant-centre’ assumptions of a decline in ecological conditions and 18 abundances towards range margins. Although much empirical research has confirmed CMH, 19 exceptions remain almost as common. We contend that mangroves provide a model system to 20 test CMH that alleviates common confounding factors and may help clarify this lack of 21 consensus. Here, we document changes in black mangrove (Avicennia germinans) population 22 genetics with 12 nuclear microsatellite loci along three replicate coastlines in the United States 23 (only 2 of 3 conform to underlying ‘abundant-centre’ assumptions). We then test an implicit 24 prediction of CMH (reduced genetic diversity may constrain adaptation at range margins) by 25 measuring functional traits of leaves associated with cold tolerance, the climatic factor that 26 controls these mangrove distributional limits. CMH predictions were confirmed only along the 27 coastlines that conform to ‘abundant-centre’ assumptions and, in contrast to theory, range margin 28 A. germinans exhibited functional traits consistent with greater cold tolerance compared to range 29 cores. These findings support previous accounts that CMH may not be a general rule across 30 species and that reduced neutral genetic diversity at range margins may not be a constraint to 31 shifts in functional trait variation along climatic gradients.

© 2018 Blackwell Verlag GmbH. Individuals in groups can suffer costs through interactions with adversarial or unknown conspecifics. Social niche construction allows individuals to buffer such potential costs by only engaging in preferred associations. This may be particularly beneficial in insect aggregations, which are often large and highly fluid. However, little is known regarding the structuring of such aggregations. Here we use social network analyses to test for fine-scale social structure in resting aggregations of the sub-social cockroach Diploptera punctata and to explore the social pressures that contribute towards such structure. We showed that females were significantly more gregarious than males and formed the core of the proximity network, thus demonstrating a higher level of social integration. This fine-scale structure is likely to result from females displacing males; females initiated most displacements whilst males received the majority. We explain this behaviour in terms of social niche construction by showing that females received significantly fewer approaches and investigations at more female-biased local sex ratios. We therefore suggest that female social clustering occurs in this, and presumably other, species to reduce potential costs associated with male harassment. This demonstrates how social niche construction can lead to higher level social structure; we suggest this approach could be used across a range of species in order to improve our understanding of the evolution of sociality.

Amphibian populations worldwide are at risk of extinction from infectious diseases, including chytridiomycosis caused by the fungal pathogen Batrachochytrium dendrobatidis (Bd). Amphibian cutaneous microbiomes interact with Bd and can confer protective benefits to the host. The composition of the microbiome itself is influenced by many environment- and host-related factors. However, little is known about the interacting effects of host population structure, genetic variation and developmental stage on microbiome composition and Bd prevalence across multiple sites. Here we explore these questions in Amietia hymenopus, a disease-affected frog in southern Africa. We use microsatellite genotyping and 16S amplicon sequencing to show that the microbiome associated with tadpole mouthparts is structured spatially, and is influenced by host genotype and developmental stage. We observed strong genetic structure in host populations based on rivers and geographic distances, but this did not correspond to spatial patterns in microbiome composition. These results indicate that demographic and host genetic factors affect microbiome composition within sites, but different factors are responsible for host population structure and microbiome structure at the between-site level. Our results help to elucidate complex within- and among- population drivers of microbiome structure in amphibian populations. That there is a genetic basis to microbiome composition in amphibians could help to inform amphibian conservation efforts against infectious diseases.

© The authors 2017. The white spotted sand bass Paralabrax albomaculatus is a member of the subfamily Serraninae and is endemic to the Galapagos Islands. Locally known as camotillo, it is an important component of the local artisanal fishery that is permitted in the Galapagos Marine Reserve. Despite its Endangered status on the IUCN Red List, and its local socio-economic importance, nothing is known about its life history. The reproductive biology of P. albomaculatus was studied from samples collected between February 2013 and March 2014. Histological examination confirmed functional gonochoristic sexual reproduction. Sex ratios were biased towards females (4.36:1), and although the size distribution of males and females overlapped, the mean ± SD total length (TL) of males (45.9 ± 8.4 cm) was significantly larger than that of females (41.5 ± 7.6 cm). Length at first maturity for females was 37 cm TL. Monthly gonado-somatic indices and the presence of eggs in the hydrated sub-phase suggest a spawning season between October and March, with a reproductive peak between November and January. Given its restricted range and continuous levels of exploitation, a management plan that includes minimum and maximum landing sizes and a seasonal closure during the reproductive season is urgently required for this Endangered Galapagos endemic.

1. Selection does not only operate in a genotype (G) × environment (E) context, but can also be modulated by the activities of organisms interacting with their environment (G × G × E). 2. The influences of aphid clonal identity and host plant (Vicia faba) intraspecific genetic variation on the performance of five genotypes of pea aphid (Acyrthosiphon pisum) were investigated – with and without interaction with a competing heterospecific clone of vetch aphid (Megoura viciae) – across three cultivars of V. faba. 3. Pea aphid performance in the presence of a competing vetch aphid clone (G × G × E) compared with the absence of competition (G × E) revealed strong context-dependent, genotype-specific shifts in performance, influenced by plant cultivar, competitor presence and their interaction. 4. The performance of vetch aphid in competition with each pea aphid clone was also compared. Here, competitor's genotype and abundance underlay a remarkably varied response by vetch aphid across interactions. 5. The study shows that aphid genotypes exhibit a varying degree of risk spreading, contingent on competitor identity and the patterns of aggregation across three plant cultivars. Owing to feedback loops between species activities and selective forces acting on them, our findings suggest that there are context-dependent responses by competitors that are shaped via the interplay of the co-occurring species and their biotic environment. 6. This work highlights the complexity of species interactions and the importance of investigating reciprocity between competition and intraspecific genetic variation. A better understanding of the eco-evolutionary interactions between phloem-feeding insects and their host plants can potentially be used to enhance crop protection and pest control.

The compostable biopolymer, poly(lactic) acid (PLA), is increasingly being used as an alternative to conventional plastics for short shelf-life products, disposable bags and packaging, and in agriculture. Despite the increase in the amount of PLA entering composting systems, few studies have examined the impact of PLA degradation on the compost microbial community. Thermophilic fungi play an import role in the composting process as they secrete hydrolytic enzymes capable of breaking down an array of complex natural polymers. In this study, the impact of PLA hydrolysis on the compost fungal community was examined by terminal restriction fragment length polymorphism and 454 sequencing. At 25°C, the effect of PLA on the surrounding compost community was relatively small and no physical changes were observed to the PLA films. However, when incubated at 50°C, where physical disintegration of PLA was occurring, a clear divergence between the compost populations in the presence and absence of PLA was evident after 2 months but became closer to the population in the absence of PLA after 4 months indicating that, after causing an initial perturbation after 2 months, the population began to return to that seen in the absence of PLA. The only exception was in the population containing 50% (w/w) PLA film, which remained divergent after 4 months and was associated with a marked acidification of the compost. Thus, 454-pyrosequencing revealed that the presence of PLA caused a strong selection for a Thermomyces sp. that was present only at low abundance in the absence of PLA.

The sensitivity of tropical forest carbon to climate is a key uncertainty in predicting global climate change. Although short-term drying and warming are known to affect forests, it is unknown if such effects translate into long-term responses. Here, we analyze 590 permanent plots measured across the tropics to derive the equilibrium climate controls on forest carbon. Maximum temperature is the most important predictor of aboveground biomass (-9.1 megagrams of carbon per hectare per degree Celsius), primarily by reducing woody productivity, and has a greater impact per °C in the hottest forests (>32.2°C). Our results nevertheless reveal greater thermal resilience than observations of short-term variation imply. To realize the long-term climate adaptation potential of tropical forests requires both protecting them and stabilizing Earth's climate., Our plot monitoring networks havebeen supported by multiple grants from a large number of funding bodies: European Research Council; Natural Environment Research Council; European Union’s Fifth, Sixth, and Seventh Framework Programme; Royal Society, Leverhulme Trust; Gordon and Betty Moore Foundation; David and Lucile Packard Foundation; State of São Paulo Research Foundation (FAPESP); National Council for Science and Technology Development of Brazil (CNPq); Agence Nationale de la Recherche; Conservation International; Missouri Botanical Garden; Smithsonian Institution; Wildlife Conservation Society; National Geographic Society; Centre for International Forestry; and Gabon’s National Park Agency.

Research Highlights: Global coffee production, especially in smallholder farming systems, is vulnerable and must adapt in the face of climate change. To this end, shaded agroforestry systems are a promising strategy. Background and Objectives: Understanding local contexts is a prerequisite for designing locally tailored systems, this can be achieved by utilizing farmers&rsquo, knowledge. Our objective is to explore ecosystem services (ESs) provided by different shade tree species as perceived by farmers and possible factors (elevation, gender, and membership in local farmers groups) influencing these perceptions. We related these factors, as well as farmers&rsquo, ESs preferences, to planting densities of tree species. Materials and Methods: During interviews with 263 small-scale coffee farmers on the southern slope of Mt. Kilimanjaro, they ranked the most common shade tree species according to perceived provision of the locally most important ESs for coffee farmers. We asked them to estimate the population of each tree species on their coffee fields and to identify the three ESs most important for their household. Results: Food, fodder, and fuelwood emerged as the most important ESs, with 37.8% of the respondents mentioning all three as priorities. Density of tree species perceived to provide these three ESs were significantly higher for farmers prioritizing these services compared to farmers that did not consider all three ESs in their top three. Albizia schimperiana scored the highest for all rankings of regulatory ESs such as coffee yield improvement, quality shade provision, and soil fertility improvement. Influence of elevation, gender, and farmer group affiliation was negligible for all rankings. Conclusions: This study shows the need to understand factors underlying farmers&rsquo, management decisions before recommending shade tree species. Our results led to the upgrade of the online tool (shadetreeadvice.org) which generates lists of potential common shade tree species tailored to local ecological context considering individual farmers&rsquo, needs.

Bespoke microsatellite marker panels are increasingly affordable and tractable to researchers and conservationists. The rate of microsatellite discovery is very high within a shotgun genomic data set, but extensive laboratory testing of markers is required for confirmation of amplification and polymorphism. By incorporating shotgun next‐generation sequencing data sets from multiple individuals of the same species, we have developed a new method for the optimal design of microsatellite markers. This new tool allows us to increase the rate at which suitable candidate markers are selected by 58% in direct comparisons and facilitate an estimated 16% reduction in costs associated with producing a novel microsatellite panel. Our method enables the visualisation of each microsatellite locus in a multiple sequence alignment allowing several important quality checks to be made. Polymorphic loci can be identified and prioritised. Loci containing fragment‐length‐altering mutations in the flanking regions, which may invalidate assumptions regarding the model of evolution underlying variation at the microsatellite, can be avoided. Priming regions containing point mutations can be detected and avoided, helping to reduce sample‐site‐marker specificity arising from genetic isolation, and the likelihood of null alleles occurring. We demonstrate the utility of this new approach in two species: an echinoderm and a bird. Our method makes a valuable contribution towards minimising genotyping errors and reducing costs associated with developing a novel marker panel. The Python script to perform our method of multi‐individual microsatellite identification (MiMi) is freely available from GitHub (https://github.com/graemefox/mimi).

© 2016 Springer-Verlag Berlin Heidelberg Connectivity, the exchange of individuals among locations, is a fundamental ecological process that explains how otherwise disparate populations interact. For most marine organisms, dispersal occurs primarily during a pelagic larval phase that connects populations. We paired population structure from comprehensive genetic sampling and biophysical larval transport modeling to describe how spiny lobster (Panulirus argus) population differentiation is related to biological oceanography. A total of 581 lobsters were genotyped with 11 microsatellites from ten locations around the greater Caribbean. The overall FST of 0.0016 (P = 0.005) suggested low yet significant levels of structuring among sites. An isolation by geographic distance model did not explain spatial patterns of genetic differentiation in P. argus (P = 0.19; Mantel r = 0.18), whereas a biophysical connectivity model provided a significant explanation of population differentiation (P = 0.04; Mantel r = 0.47). Thus, even for a widely dispersing species, dispersal occurs over a continuum where basin-wide larval retention creates genetic structure. Our study provides a framework for future explorations of wide-scale larval dispersal and marine connectivity by integrating empirical genetic research and probabilistic modeling.

Adapting coffee production to climate change is a significant challenge requiring a detailed understanding of local climatic change patterns and the consequences, both real and perceived, for coffee production. To this end, we examined changes in precipitation at Mt. Kilimanjaro over the last two decades and conducted twelve focus group discussions to obtain farmers&rsquo, perceptions on climate change, the impact of extreme weather events on coffee production and the potential of shade trees as an adaptation strategy. Despite an increase in total annual precipitation, farmers are still confronted with droughts due to a shift in seasons. We found a delayed onset of the main rainy season and showed that a positive Indian Ocean Dipole contributes to the increase in precipitation during the short rainy season. Farmers clearly described the impacts of drought or excess rainfall on coffee production during flowering, maturation, and harvest. Thus, adaptation strategies need to be tailored such that specific coffee development stages are buffered against the effects of droughts, shorter wet seasons, and less frequent but heavier rainfall events. To develop the potential of shade trees as an effective adaptation strategy, optimum shade density, specific tree species, and management practices need to be identified.

Climate-driven range expansion of ecosystem-defining foundation species can have wide-reaching ecological consequences. Expansion may also result in mating system changes in these foundation species because of the ecological characteristics of range margins, such as greater conspecific isolation and reduced pollinator availability. It is important to understand how mating systems may change during expansion due to their direct influence on intraspecific genetic and demographic dynamics. Here, we used 12 microsatellite loci to genotype progeny arrays of the neotropical black mangrove (Avicennia germinans) at six collection sites (n = 23 maternal trees; 1,612 genotyped propagules) along a latitudinal gradient towards a northern distributional limit on the Atlantic coast of Florida, USA (27.56–30.01oN), where mangroves have expanded into salt marsh over the past several decades. We assessed mating system variation at three spatial scales. First, at the species-distribution level, published outcrossing rates for tropical conspecifics were more than two times higher than those for subtropical Florida A. germinans, consistent with reductions in pollinator diversity and in mangrove abundance with latitude. Second, at the population level, Florida outcrossing rates did not systematically decline towards the northern range limit, but instead, a more open pollen-dispersal neighbourhood at the transition from mangrove to salt marsh dominance may elevate outcrossing until conspecific abundances become too low towards the range limit. Third, at the individual level, outcrossing increased as conspecific cover increased at the Florida range margin, consistent with density-dependent plastic shifts in mating system. These findings suggest that ecological structure influences the A. germinans mating system at varying spatial scales. Further research needs to evaluate the effect of A. germinans mating system variation on the survival and fitness of offspring and on the extent of population-level local adaptation at expanding distributional limits.

Etorphine-azaperone immobilisation was evaluated for translocation of Masai giraffes. Nine giraffes were darted with 0.012 &plusmn, 0.001 mg/kg etorphine and 0.07 &plusmn, 0.01 mg/kg azaperone. Once ataxic, giraffes were roped for recumbency and restrained manually. Naltrexone (3 mg/mg etorphine) was immediately given intravenously to reverse etorphine-related side effects. Protocol evaluation included physiological monitoring, blood-gas analyses, anaesthetic times, and quality scores (1 = excellent, 4 = poor). Sedation onset and recumbency were achieved in 2.6 &plusmn, 0.8 and 5.6 &plusmn, 1.4 min. Cardio-respiratory function (HR = 70 &plusmn, 16, RR = 32 &plusmn, 8, MAP = 132 &plusmn, 16) and temperature (37.8 &plusmn, 0.5) were stable. Arterial gas analysis showed hypoxaemia in some individuals (PaO2 = 67 &plusmn, 8 mmHg) and metabolic acidosis (pH = 7.23 &plusmn, 0.05, PaCO2 = 34 &plusmn, 4 mmHg, HCO3&minus, = 12.9 &plusmn, 1.2 mmol/l). Minor startle response occurred, while higher induction-induced excitement correlated to longer inductions, worse restraint, and decreased HCO3&minus, After 19 &plusmn, 3.5 min of restraint, giraffes were allowed to stand and were loaded onto a chariot. Immobilisations were good and scored 2 (1&ndash, 3). Inductions and recoveries were smooth and scored 1 (1&ndash, 2). Translocations were uneventful and no complications occurred in 14-days boma follow-up.

1. The ability to define the spatial dynamics of fish stocks is critical to fisheries man- agement. Combating illegal, unreported and unregulated fishing and the regula- tion of area-based management through physical patrols and port side controls are growing areas of management attention. Augmenting the existing approaches to fisheries management with forensic techniques has the potential to increase compliance and enforcement success rates. 2. We tested the accuracy of three techniques (genotyping, otolith microchemistry and morphometrics) that can be used to identify geographic origin. We used fish caught from three fishing grounds, separated by a minimum of 5 km and a maxi- mum of 60 km, to test the accuracy of these approaches at relatively small spatial scales. 3. Using nearest-neighbour analyses, morphometric analysis was the most accurate (79.5%) in assigning individual fish to their fishing ground of origin. Neither otolith microchemistry (54.0%) or genetic analyses (52.4%) had sufficient accuracy at the spatial scales we examined. 4. Synthesis and applications. The combination of accuracy and minimal resource re- quirements make morphometric analysis a promising tool for assessing compli- ance with area-based fishing restrictions at the scale of kilometres. Furthermore, this approach has promising application, in small-scale fisheries through to com- munity-based management approaches where technical and financial resources are limited.

Mangroves are declining globally at faster rates than tropical forests and coral reefs, with primary threats including, aquaculture, agriculture and climate change. Mangroves provide ecosystem services to coastal communities of Mexico, Belize, Guatemala and Honduras, which comprise the Mesoamerican Reef (MAR) ecoregion. Over the past two decades mangroves within the MAR have declined. Current estimates of mangrove cover in the region suggest that mangroves cover 239,176 ha of the MAR, equivalent to 1.7% of the world's mangroves. Concerted efforts to manage, conserve and protect mangrove forest are apparent in all four countries. Comprehensive laws that prohibit the cutting and clearing of mangroves have been implemented in Mexico, Guatemala and Honduras. Belize has a permitting system to regulate mangrove alterations. In addition, a total of seven international and regional agreements have been ratified. Across the ecoregion, forty-three protected areas have been designated that contain mangroves, providing protection to 111,396 ha of mangroves (47% of the total). However, our findings suggest a lack of transparency in the governance framework, a disconnect between management and research, and geopolitical differences have all played a role in reducing management efficacy. A key finding of our study reveals a distinct division in the perceived major threats to mangroves between Ramsar site managers and researchers. Ramsar site managers identify anthropogenic disturbances as key threats, while in contrast, the bulk of research focuses on natural disturbances. To promote the inclusion of evidence-based research within mangrove management plans, greater efforts to connect these important stakeholders are required.

Management efforts for improving the sustainability of the Caribbean spiny lobster (Panulirus argus) fishery require knowledge of population connectivity. The aim of this study is to investigate population connectivity of P. argus at two levels: (1) spatially between two marine protected areas (MPAs) in the Caribbean coast of Mexico, and (2) temporally within MPAs; by genotyping discrete size classes lobsters using microsatellite markers. No evidence of population differentiation between lobster populations from Banco Chinchorro and Sian Ka’an MPAs was found (P = 0.139). In contrast significant levels of population differentiation among discrete size classes of lobsters was found (FST = 0.0054; P = 0.0052). Temporal variation among the genotypes of new larval recruits may explain these results. Future research will be required to directly test the genotypes of new larval recruits in Banco Chinchorro and Sian Ka’an MPAs to confirm this hypothesis.

An article published by Archives of Agronomy and Soil Science, 2016 Vol. 62, No. 2, 199–215, http://dx.doi.org/10.1080/03650340.2015.1040399

[This corrects the article DOI: 10.1371/journal.pone.0185151.].

Mosquito-borne pathogens pose major threats to both wildlife and human health and, largely as a result of unintentional human-aided dispersal of their vector species, their cumulative threat is on the rise. Anthropogenic climate change is expected to be an increasingly significant driver of mosquito dispersal and associated disease spread. The potential health implications of changes in the spatio–temporal distribution of mosquitoes highlight the importance of ongoing surveillance and, where necessary, vector control and other health-management measures. The World Association of Zoos and Aquariums initiative, Project MOSI, was established to help protect vulnerable wildlife species in zoological facilities from mosquito-transmitted pathogens by establishing a zoo-based network of fixed mosquito monitoring sites to assist wildlife health management and contribute data on mosquito spatio–temporal distribution changes. A pilot study for Project MOSI is described here, including project rationale and results that confirm the feasibility of conducting basic standardized year-round mosquito trapping and monitoring in a zoo environment.

Marine protected areas (MPAs) are an important ecosystem-based management approach to help improve the sustainability of the spiny lobster fishery (Panulirus argus), but information is lacking concerning levels of lobster population connectivity among MPAs. Given their prolonged (~6 months) pelagic larval duration, population connectivity must be considered in any spatial management plan for P. argus. We used genetic techniques to uncover spatial patterns of connectivity among MPAs along the Mesoamerican Barrier Reef (MBRS) of Central America. We hypothesized that connectivity would be greater and genetic differentiation diminished among lobster populations within MPAs in the southern MBRS, which is dominated by a retentive oceanographic environment, as compared to MPAs in the more advective environment further north. We found that levels of connectivity are high among spiny lobster populations residing in MPAs in Central America, although overall F ST was low (F ST = 0.00013) but significant (P = 0.037). MPAs in the northern MBRS contained significantly more individuals that were genetically determined outliers or migrants than southern MPAs (P = 0.008, R 2 = 0.61), which may have contributed to the higher levels of genetic differentiation observed in northern MPAs. Direct genetic testing of larvae and adults will be required to confirm this hypothesis. The high level of connectivity among MPAs provides additional evidence of the importance of international cooperation in the management of Caribbean lobster fisheries. However, uncertainty regarding the ecological and physical drivers of genetic differentiation in Northern MPAs implies that managers should hedge against uncertainty.

The application of biochar with inorganic fertilizers is shown to improve crop productivity. However, resource-poor farmers may be constrained in their ability to meet the fertilizer requirements. In this short-term greenhouse research, we investigated whether combining biochar and green manure sources of Tithonia diversifolia and Vicia faba could be a viable soil management option for smallholder agroecosystems. Generally, the application of the green manures either singly or mixed with biochar showed similar effects on soil properties. However, in contrast to mixed biochar and fertilizer treatments, soil microbial biomass C, mineral N, available P, and pH were generally higher in soils that received mixed green manure and biochar applications. The results also showed a positive but comparable synergistic effect of applying green manure or fertilizers with biochar. It was inferred that the combined applications of biochar and V. faba or T. diversifolia increased maize grain yield by 35 and 25 %, respectively, compared with sole V. faba and T. diversifolia applications. Relative to sole fertilizer application, there was a 27 % increase in maize grain yield when fertilizer was combined with biochar. The increased biological yield of maize in mixed than single treatments was attributed to the increased N use efficiency of maize plants that received mixed application of biochar and green manures or inorganic fertilizer. The results established that in places where inorganic fertilizers are limited, green manures could be applied with biochar for improved soil fertility and crop productivity.

Many amphibian species are dependent on ex situ conservation interventions for their long-term persistence. However, projects have been jeopardised by husbandry issues involving poor calcium metabolism and nutritional metabolic bone disease (NMBD). Healthy calcium metabolism requires appropriate dietary calcium content and access to vitamin D3 . In many animals, vitamin D3 can be photobiosynthesised in skin exposed to UVB radiation, as well as extracted from the diet, but the extent of vitamin D3 photobiosynthesis in amphibians is poorly known. Additionally, prey insects for captive amphibians are deficient in calcium and calcium content must be artificially increased, but the effects of different levels of augmentation and their interaction with UVB exposure are also little understood. We fed captive fire-bellied toads (Bombina orientalis) with crickets augmented to contain 5% and 10% calcium and housed them with and without UVB exposure. Despite additional dietary vitamin D3 supplementation, we found that toads exposed to UVB radiation exhibited significantly higher serum vitamin D3 levels, indicating that this species may partly rely on photobiosynthesis sources of vitamin D3 . These data are the first to show a direct link between UVB exposure and serum vitamin D3 in an amphibian. We found significant positive effects of UVB exposure and 10% dietary calcium content on skeletal structure, as well as complex interactions between treatments. We also found UVB radiation exposure resulted in more rapid natural coloration acquisition. Together, this indicates that standard calcium plus vitamin D3 supplementation methods may not fully substitute for UVB exposure and for increased feeder insect calcium content. This may have implications for the success of ex situ amphibian conservation, as well as for the welfare of captive amphibians in general. Our data lend support for the provision of UVB radiation for captive, basking amphibians.

Genetic variation in plants can influence the community structure of associated species, through both direct and indirect interactions. Herbivorous insects are known to feed on a restricted range of plants, and herbivore preference and performance can vary among host plants within a species due to genetically based traits of the plant (e.g., defensive compounds). In a natural system, we expect to find genetic variation within both plant and herbivore communities and we expect this variation to influence species interactions. Using a three-species plant-aphid model system, we investigated the effect of genetic diversity on genetic interactions among the community members. Our system involved a host plant (Hordeum vulgare) that was shared by an aphid (Sitobion avenae) and a hemi-parasitic plant (Rhinanthus minor). We showed that aphids cluster more tightly in a genetically diverse host-plant community than in a genetic monoculture, with host-plant genetic diversity explaining up to 24% of the variation in aphid distribution. This is driven by differing preferences of the aphids to the different plant genotypes and their resulting performance on these plants. Within the two host-plant diversity levels, aphid spatial distribution was influenced by an interaction among the aphid's own genotype, the genotype of a competing aphid, the origin of the parasitic plant population, and the host-plant genotype. Thus, the overall outcome involves both direct (i.e., host plant to aphid) and indirect (i.e., parasitic plant to aphid) interactions across all these species. These results show that a complex genetic environment influences the distribution of herbivores among host plants. Thus, in genetically diverse systems, interspecific genetic interactions between the host plant and herbivore can influence the population dynamics of the system and could also structure local communities. We suggest that direct and indirect genotypic interactions among species can influence community structure and processes.

The application of organic materials with wide carbon-to-nitrogen (C-to-N) ratios is known to cause initial immobilization of nutrients, unless N fertilizers are applied. In Sub-Saharan Africa, regular application of mineral fertilizers with organic residues is seldom practiced due to several socioeconomic constraints. In the present study, we assessed the biomass qualities of Zea mays, Tithonia diversifolia and Vicia faba and evaluated whether delayed decomposition and nutrient release of low quality residues will improve when mixed with high quality residues. Our hypothesis was that high quality organic residues have high N supply capabilities to improve decomposition and nutrient release of low quality materials when mixed together. Compared with V. faba and T. diversifolia biomasses, Z. mays residue was found to be relatively poor in quality as a result of its relatively low N concentration (10.8 g/kg) and wider C-to-N ratio (37.2:1). The assessment on biomass quality was consistent with the results on decomposition. After one week, 42 % of Z. mays residues had decomposed compared with more than 90 % of T. diversifolia and V. faba residues. Further, the decomposition and N release rate of Z. mays tripled when mixed with either T. diversifolia or V. faba biomass. In this study, the initial N, C, lignin, C-to-N ratio, lignin-to-N ratio and (lignin + polyphenol)/N ratio of the residues were useful indicators of degradability and nutrient release based on significant (P