How healthy are America's plants, animals and environment?

Dr. Aronson is the author or co-author of more than 200 journal articles and 17 books, and continues to travel, consult and publish widely.

Mount St. Helens' explosive eruption on May 18, 1980, was a pivotal moment in the field of disturbance ecology.

Morels are prized edible mushrooms that fruit, sometimes prolifically, in many forest types throughout western North America. They are collected for personal consumption and commercially harvested as valuable special (nontimber) forest products. Large gaps remain, however, in our knowledge about their taxonomy, biology, ecology, cultivation, safety, and how to manage forests and harvesting activities to conserve morel populations and ensure sustainable crops. This publication provides forest managers, policymakers, mycologists, and mushroom harvesters with a synthesis of current knowledge regarding these issues, regional summaries of morel harvesting and management, and a comprehensive review of the literature.

Morels are prized edible mushrooms that fruit, sometimes prolifically, in many forest types throughout western North America. They are collected for personal consumption and commercially harvested as valuable special (nontimber) forest products. Large gaps remain, however, in our knowledge about their taxonomy, biology, ecology, cultivation, safety, and how to manage forests and harvesting activities to conserve morel populations and ensure sustainable crops. This publication provides forest managers, policymakers, mycologists, and mushroom harvesters with a synthesis of current knowledge regarding these issues, regional summaries of morel harvesting and management, and a comprehensive review of the literature.

Hemlock dwarf mistletoe (Arceuthobium tsugense [Rosendahl] G.N. Jones) is a small, inconspicuous parasite that has significant effects on tree growth and stand structure in coastal forest ecosystems of western North America. Most previous research focused on the effects of hemlock dwarf mistletoe on timber production. Previous clearcut harvesting of large areas that removed virtually all infected trees and forestry practices that established even-aged stands of trees effectively prevented or minimized future hemlock dwarf mistletoe impacts. Under this regime, further research on hemlock dwarf mistletoe was considered unnecessary. However, current forestry practices that restrict clearcut harvesting to small openings and retain live trees to preserve attributes of old-growth forests create conditions that appear highly favorable for enhanced seed production by hemlock dwarf mistletoe, early spread of the mistletoe to infect young trees, and, consequently, increased growth impacts to residual trees over time. More information is needed on the biology and impacts of hemlock dwarf mistletoe in coastal western hemlock retention harvested forests in the United States of America and Canada. Further work is recommended to develop sampling and monitoring procedures to determine hemlock dwarf mistletoe spread and impacts. We also need to investigate several unusual aspects of hemlock dwarf mistletoe biology and development such as long-distance seed dispersal and persistence in old-growth forests. Detailed tree, stand, and forest-level models are needed to monitor and project hemlock dwarf mistletoe effects over a wide range of ecological conditions and management regimes in coastal forests.

Forests of the Pacific Northwest have been an epicenter for the evolution of truffle fungi with over 350 truffle species and 55 genera currently identified. Truffle fungi develop their reproductive fruit-bodies typically belowground, so they are harder to find and study than mushrooms that fruit aboveground. Nevertheless, over the last five decades, the Corvallis Forest Mycology program of the Pacific Northwest Research Station has amassed unprecedented knowledge on the diversity and ecology of truffles in the region. Truffle fungi form mycorrhizal symbioses that benefit the growth and survival of many tree and understory plants. Truffle fruit-bodies serve as a major food souce for many forest-dwelling mammals. A few truffle species are commercially harvested for gourmet consumption in regional restaurants. This publication explores the biology and ecology of truffle fungi in the Pacific Northwest, their importance in forest ecosystems, and effects of various silvicultural practices on sustaining truffle populations. General management principles and considerations to sustain this valuable fungal resource are provided.

How is coronavirus affecting China, India and the Asia Pacific?

Vic Jurskis says his new book, Firestick Ecology, is a simple story of how Aboriginal people managed the land through fire to create and maintain the biodiversity and the fire-safe environment that greeted the first European settlers. The sub-title is 'fairdinkum science in plain English'. He says that to conserve biodiversity and live safely, we need to manage our forests with fire 'willingly, frequently and, with practice, skilfully'. The evidence of our land management failure is all around us, he says.

Tribune News Service Faridabad, January 24 Despite an overall lull in the real estate sector, illegal construction and encroachment in certain parts of the district appear to be going on in “full swing”. These include the hilly terrain of the Aravallis. However, the authorities have removed certain encroachments from the Surajkund area in the past. “Several construction activities have been noticed in the area, including the Surajkund road. As the non-forest area comes under the jurisdiction of the Municipal Corporation Faridabad (MCF), it has removed certain encroachments in the past,” said a source in the civic body. Admitting that illegal construction poses a threat to the green cover of the […]

Degradation and loss of natural habitat is the major driver of the current global biodiversity crisis. Most habitat conservation efforts to date have targeted small areas of highly threatened habitat, but emerging debate suggests that retaining large intact natural systems may be just as important. We reconcile these perspectives by...

Gastrointestinal (GI) or gut microbiotas play essential roles in host development and physiology. These roles are influenced partly by the microbial community composition. During early developmental stages, the ecological processes underlying the assembly and successional changes in host GI community composition are influenced by numerous factors, including dispersal from the surrounding environment, age-dependent changes in the gut environment, and changes in dietary regimes. However, the relative importance of these factors to the gut microbiota is not well understood. We examined the effects of environmental (diet and water sources) and host early ontogenetic development on the diversity of and the compositional changes in the gut microbiota of a primitive teleost fish, the lake sturgeon (Acipenser fulvescens), based on massively parallel sequencing of the 16S rRNA gene. Fish larvae were raised in environments that differed in water source (stream versus filtered groundwater) and diet (supplemented versus nonsupplemented Artemia fish). We quantified the gut microbial community structure at three stages (prefeeding and 1 and 2 weeks after exogenous feeding began). The diversity declined and the community composition differed significantly among stages; however, only modest differences associated with dietary or water source treatments were documented. Many taxa present in the gut were over- or underrepresented relative to neutral expectations in each sampling period. The findings indicate dynamic relationships between the gut microbiota composition and host gastrointestinal physiology, with comparatively smaller influences being associated with the rearing environments. Neutral models of community assembly could not be rejected, but selectivity associated with microbe-host GI tract interactions through early ontogenetic stages was evident. The results have implications for sturgeon conservation and aquaculture production specifically and applications of microbe-based management in teleost fish generally.

IMPORTANCE We quantified the effects of environment (diet and water sources) and host early ontogenetic development on the diversity of and compositional changes in gut microbial communities based on massively parallel sequencing of the 16S rRNA genes from the GI tracts of larval lake sturgeon (Acipenser fulvescens). The gut microbial community diversity declined and the community composition differed significantly among ontogenetic stages; however, only modest differences associated with dietary or water source treatments were documented. Selectivity associated with microbe-host GI tract interactions through early ontogenetic stages was evident. The results have implications for lake sturgeon and early larval ecology and survival in their natural habitat and for conservation and aquaculture production specifically, as well as applications of microbe-based management in teleost fish generally.

Biological nitrogen fixation can be an important source of nitrogen in tropical forests that serve as a major CO₂ sink. Extensive deforestation of the Amazon is known to influence microbial communities and the biogeochemical cycles they mediate. However, it is unknown how diazotrophs (nitrogen-fixing microorganisms) respond to deforestation and subsequent ecosystem conversion to agriculture, as well as whether they can recover in secondary forests that are established after agriculture is abandoned. To address these knowledge gaps, we combined a spatially explicit sampling approach with high-throughput sequencing of nifH genes. The main objectives were to assess the functional distance decay relationship of the diazotrophic bacterial community in a tropical forest ecosystem and to quantify the roles of various factors that drive the observed changes in the diazotrophic community structure. We observed an increase in local diazotrophic diversity (α-diversity) with a decrease in community turnover (β-diversity), associated with a shift in diazotrophic community structure as a result of the forest-to-pasture conversion. Both diazotrophic community turnover and structure showed signs of recovery in secondary forests. Changes in the diazotrophic community were primarily driven by the change in land use rather than differences in geochemical characteristics or geographic distances. The diazotroph communities in secondary forests resembled those in primary forests, suggesting that at least partial recovery of diazotrophs is possible following agricultural abandonment.

IMPORTANCE The Amazon region is a major tropical forest region that is being deforested at an alarming rate to create space for cattle ranching and agriculture. Diazotrophs (nitrogen-fixing microorganisms) play an important role in supplying soil N for plant growth in tropical forests. It is unknown how diazotrophs respond to deforestation and whether they can recover in secondary forests that establish after agriculture is abandoned. Using high-throughput sequencing of nifH genes, we characterized the response of diazotrophs’ β-diversity and identified major drivers of changes in diazotrophs from forest-to-pasture and pasture-to-secondary-forest conversions. Studying the impact of land use change on diazotrophs is important for a better understanding of the impact of deforestation on tropical forest ecosystem functioning, and our results on the potential recovery of diazotrophs in secondary forests imply the possible restoration of ecosystem functions in secondary forests.

Microbial mat communities are associated with extensive (~700 km²) and morphologically variable carbonate structures, termed microbialites, in the hypersaline Great Salt Lake (GSL), Utah. However, whether the composition of GSL mat communities covaries with microbialite morphology and lake environment is unknown. Moreover, the potential adaptations that allow the establishment of these extensive mat communities at high salinity (14% to 17% total salts) are poorly understood. To address these questions, microbial mats were sampled from seven locations in the south arm of GSL representing different lake environments and microbialite morphologies. Despite the morphological differences, microbialite-associated mats were taxonomically similar and were dominated by the cyanobacterium Euhalothece and several heterotrophic bacteria. Metagenomic sequencing of a representative mat revealed Euhalothece and subdominant Thiohalocapsa populations that harbor the Calvin cycle and nitrogenase, suggesting they supply fixed carbon and nitrogen to heterotrophic bacteria. Fifteen of the next sixteen most abundant taxa are inferred to be aerobic heterotrophs and, surprisingly, harbor reaction center, rhodopsin, and/or bacteriochlorophyll biosynthesis proteins, suggesting aerobic photoheterotrophic (APH) capabilities. Importantly, proteins involved in APH are enriched in the GSL community relative to that in microbialite mat communities from lower salinity environments. These findings indicate that the ability to integrate light into energy metabolism is a key adaptation allowing for robust mat development in the hypersaline GSL.

IMPORTANCE The earliest evidence of life on Earth is from organosedimentary structures, termed microbialites, preserved in 3.481-billion-year-old (Ga) rocks. Phototrophic microbial mats form in association with an ~700-km² expanse of morphologically diverse microbialites in the hypersaline Great Salt Lake (GSL), Utah. Here, we show taxonomically similar microbial mat communities are associated with morphologically diverse microbialites across the lake. Metagenomic sequencing reveals an abundance and diversity of autotrophic and heterotrophic taxa capable of harvesting light energy to drive metabolism. The unexpected abundance of and diversity in the mechanisms of harvesting light energy observed in GSL mat populations likely function to minimize niche overlap among coinhabiting taxa, provide a mechanism(s) to increase energy yield and osmotic balance during salt stress, and enhance fitness. Together, these physiological benefits promote the formation of robust mats that, in turn, influence the formation of morphologically diverse microbialite structures that can be imprinted in the rock record.

The most recent U.N. demographic projections show world population growing to 9.3 billion by 2050, an addition of 2.3 billion people.

The Rs 6300-crore plans for development of the Ganga waterway from Allahabad to Haldia should be undertaken only after meticulous examination of its impact on various elements of river ecology. Debadityo Sinha explains why.

The ongoing vigorous debate between wildlife enthusiasts and tribal rights activists must be steered by a vital lesson from past conservation failures - that India's unparalleled riches of biodiversity can only be protected by working with, rather than against, the rural and tribal communities who live closest to them, writes Ramachandra Guha.

Cham : Springer, c2019.

[S.l.] : SPRINGER NATURE, 2020.

Cham : Springer, 2020.

Amsterdam : Elsevier, 2018.

Edinburgh : Elsevier, 2020.

Hayden Library - QH353.P4745 2018

Toy, Eugene C., author

London : Academic Press, 2020.

Hayden Library - QH456.H55 2019

Dewey Library - QH331.F35 2019

Should people have the same rights and obligations online as they do in the real world? MIT computer scientist Alex “Sandy” Pentland explains how developing social networks as trusted networks will help establish a sustainable digital ecology for years to come.

Online Resource

Rotch Library - BF353.G53 2019

Dewey Library - BF311.M34 2017

Meise, Belgium : National Botanic Garden of Belgium : Royal Botanical Society of Belgium

Sisaye, Seleshi, 1951- author

Hayden Library - QP376.F7413 2018

Nguyen, An Thinh, author