Microbes in high arctic snow and implications for the cold biosphere

We applied molecular, microscopic, and culture techniques to characterize the microbial communities in snow and air at remote sites in the Canadian High Arctic (Ward Hunt Island, Ellesmere Island, and Cornwallis Island, latitudes 74 to 83(o)N). Members of the Bacteria and Eukarya were prevalent in the snow, and their small subunit (SSU) rRNA gene signatures indicated strong local aerial transport within the region over the preceding 8 months of winter snowpack accumulation. Many of the operational taxonomic units (OTUs) were similar to previously reported SSU rRNA gene sequences from the Arctic Ocean, suggesting the importance of local aerial transport processes for marine microbiota. More than 47% of the cyanobacterial OTUs in the snow have been previously found in microbial mats in the region, indicating that this group was also substantially derived from local sources. Viable cyanobacteria isolated from the snow indicated free exchange between the snow and adjacent mat communities. Other sequences were most similar to those found outside the Canadian Arctic but were from snow, lake and sea ice, glaciers and permafrost, alpine regions, Antarctica, and other regions of the Arctic, supporting the concept of global distribution of microbial ecotypes throughout the cold biosphere.     

Prokaryotic biosphere

The life philosophy aspects of natural sciences are discussed. The key role of prokaryotes in the origin, development, and existence of the biosphere is considered. It helps to understand how the penetration in the world of prokaryotes changes our notions of the place of biology in natural sciences.     

Origin of biosphere

Concepts of origin of life on the planet are briefly considered. The problem of origin of biosphere is discussed, with a suggestion that the origin of living organisms and biosphere are two aspects of the same process. There is put forward a hypothesis of embryosphere—the primary medium, in which preorganisms could appear. The ecosystemic approach to origin of life poses question about sources of the matter and energy used by the primary life as well as about causes of the biochemical unity that exists in all Earth organisms.     

黑果腺肋花楸枝条的深超冷与抗寒性

差热分析法测得黑果腺肋花楸枝条有深超冷。黑果腺肋花楸低温放热峰的起始温度和组织褐变法测得的致死温度相吻合。以黑果腺肋花楸低温放热峰的起始温度作为枝条的抗寒性指标,抗寒性的季节变化表现为：晚秋至１２月上旬为抗寒性驯化阶段,１２月上旬至次年２月上旬为最强抗寒性维持阶段,２月上旬以后开始脱锻炼。初冬后的锻炼过程和早春的脱锻炼过程十分迅速并与环境温度密切相关。     

Bioengineering the biosphere?

Our planet is experiencing an accelerated process of change associated to a variety of anthropogenic phenomena. The future of this transformation is uncertain, but there is general agreement about its negative unfolding that might threaten our own survival. Furthermore, the pace of the expected changes is likely to be abrupt: catastrophic shifts might be the most likely outcome of this ongoing, apparently slow process. Although different strategies for geo-engineering the planet have been advanced, none seem likely to safely revert the large-scale problems associated to carbon dioxide accumulation or ecosystem degradation. An alternative possibility considered here is inspired in the rapidly growing potential for engineering living systems. It would involve designing synthetic organisms capable of reproducing and expanding to large geographic scales with the goal of achieving a long-term or a transient restoration of ecosystem-level homeostasis. Such a regional or even planetary-scale engineering would have to deal with the complexity of our biosphere. It will require not only a proper design of organisms but also understanding their place within ecological networks and their evolvability. This is a likely future scenario that will require integration of ideas coming from currently weakly connected domains, including synthetic biology, ecological and genome engineering, evolutionary theory, climate science, biogeography and invasion ecology, among others.     

The science of the biosphere

This paper considers the needs and potentials for the development of the biosphere. An emphasis is placed on the unusual qualities of the biosphere, such as important time lags, interactions between life and its environment at large scales, and biological evolution, which has led to large scale changes in the environment during the Earth's history. These qualities require a different approach to the development of a theory for this large scale system than has been used in the past, when the biosphere was treated as a steady-state, quasilinear system. Other aspects of the development of the science of the biosphere, including the use of remote sensing, are reviewed, and the application of these techniques to the estimation of certain biological variables is discussed.     

Review: from chemosphere to biosphere

An understanding of how the Earth's chemosphere was transformed to a biosphere is central to our understanding of the origin of life and the search for extraterrestrial life or life signatures. Once early prokaryotic life originated and colonized the Earth, the biosphere was well on its way to being formed. In this paper, information and knowledge is integrated to examine the possibility how life first self-assembled and transformed a lifeless chemosphere into a complex biosphere that we still do not understand today.     

Upper boundary of the biosphere.

By using meterological rockets fitted with specially designed analyzers, samples for microbiological investigation have been taken. The analyzer design prevented extraneous microorganisms from penetrating into the analyzer. Before being used, the analyzers were sterilized with high gamma-ray doses. For the first time microorganisms have been detected in the mesosphere at an altitude of 48 to 77 km. The microorganisms are microscopic fungi having black conidia or spores (Circinella muscae, Aspergillus niger, Papulaspora anomala) and one species forming green conidia (Penicillium notatum). Colonies of Mycobacterium luteum and Micrococcus albus have also grown. Five of the six species have synthesized pigments. The presence of pigmented microbial forms leads us to believe that natural selection is occurring in the mesosphere because cells possessing chromogenous pigments (carotenoids, melanins) are more resistant to ultraviolet-ray action. A greater number of microorganisms have been registered in the mesosphere during dust storms than in the absence of strong winds.     

Humic substances in the early biosphere

Humic substances and their organic-mineral compounds are the first stage in transformation of biotic residues into stable geopolymers, which comprise the main reservoir of organic C in the biosphere. Early appearance of HS in the Earth’s history is of principal importance for the understanding of geo-biological processes on land in the past. However, there is no fossil record of HS before land colonization by lignified vegetation (400 Ma). When the first soil HS were formed? Could HS be synthesized in the Precambrian before plants and mosses terrestrialization? The formation of HS occurs in mesophilic aerobic conditions and requires presence of oxidative catalysts and production of aromatic (phenolic) precursors by biota. In this paper, humification processes in algo-myco-bacterial and lichen communities are discussed from actualistic point of view. These communities are considered as a relict ecosystem, which could dominate on land during the Neoproterozoic-Early Paleozoic (1–0.5 Ga).     

Primary production: The biosphere and man

The net primary production of the biosphere is about 160×10 ⁹ tons/year, with 34% of this in marine, 0.8% in freshwater, and 66% in terrestrial ecosystems. World biomass (in the year 1950) is estimated as 1840×10⁹ tons of dry matter, strongly concentrated on the continents (99.8%) and mostly in forests (90%). The total chlorophyll of the biosphere is about 240×10⁶ tons; with about 90% of this on land. Land communities typically have 3–8 m² of leaf surface and 1–4 g of chlorophyll per m² of ground surface; chlorophyll in the oceans ranges mostly downward from 0.5 g/m². Terrestrial and marine communities are in contrast in their mean ratios of biomass to net annual productivity (17.3 and 0.07) and of net annual productivity to chlorophyll (473 and 3100g/g). Man harvests about 1.3×10⁹ tons/year of food from the land surface, about 17×10⁶ tons/year from water bodies, with 88% of this from the seas. Despite the immensity of the biosphere, man has reduced its biomass and is beginning, with pollution, to affect its productivity. The relation of an exponentially increasing human population and industry to the biosphere is thus unstable. Some characteristics of this instability and the different consequences of overgrowth for poor or developing and rich or developed countries are considered.This paper was presented at the symposium, The Primary Production of the Biosphere, given at the Second Congress of the American Institute of Biological Sciences, Miami, Florida, October 24, 1971.     

Water: the bloodstream of the biosphere

Water, the bloodstream of the biosphere, determines the sustainability of living systems. The essential role of water is expanded in a conceptual model of energy dissipation, based on the water balance of whole landscapes. In this model, the underlying role of water phase changes--and their energy-dissipative properties--in the function and the self-organized development of natural systems is explicitly recognized. The energy-dissipating processes regulate the ecological dynamics within the Earth's biosphere, in such a way that the development of natural systems is never allowed to proceed in an undirected or random way. A fundamental characteristic of self-organized development in natural systems is the increasing role of cyclic processes while loss processes are correspondingly reduced. This gives a coincidental increase in system efficiency, which is the basis of growing stability and sustainability. Growing sustainability can be seen as an increase of ecological efficiency, which is applicable at all levels up to whole landscapes. Criteria for necessary changes in society and for the design of the measures that are necessary to restore sustainable landscapes and waters are derived.