Human alteration of Earth is substantial and growing. Between one-third and one-half of the land surface has been transformed by human action; the carbon dioxide concentration in the atmosphere has increased by nearly 30 percent since the beginning of the Industrial Revolution; more atmospheric nitrogen is fixed by humanity than by all natural terrestrial sources combined; more than half of all accessible surface fresh water is put to use by humanity; and about one-quarter of the bird species on Earth have been driven to extinction. By these and other standards, it is clear that we live on a human-dominated planet.

/pdf/human-domination-of-earth-s-ecosystems-5eevmqq987.pdf

Human Domination of Earth's Ecosystems

This paper describes the contents of the 2016 edition of the HITRAN molecular spectroscopic compilation. The new edition replaces the previous HITRAN edition of 2012 and its updates during the intervening years. The HITRAN molecular absorption compilation is composed of five major components: the traditional line-by-line spectroscopic parameters required for high-resolution radiative-transfer codes, infrared absorption cross-sections for molecules not yet amenable to representation in a line-by-line form, collision-induced absorption data, aerosol indices of refraction, and general tables such as partition sums that apply globally to the data. The new HITRAN is greatly extended in terms of accuracy, spectral coverage, additional absorption phenomena, added line-shape formalisms, and validity. Moreover, molecules, isotopologues, and perturbing gases have been added that address the issues of atmospheres beyond the Earth. Of considerable note, experimental IR cross-sections for almost 300 additional molecules important in different areas of atmospheric science have been added to the database. The compilation can be accessed through www.hitran.org. Most of the HITRAN data have now been cast into an underlying relational database structure that offers many advantages over the long-standing sequential text-based structure. The new structure empowers the user in many ways. It enables the incorporation of an extended set of fundamental parameters per transition, sophisticated line-shape formalisms, easy user-defined output formats, and very convenient searching, filtering, and plotting of data. A powerful application programming interface making use of structured query language (SQL) features for higher-level applications of HITRAN is also provided.

/pdf/the-hitran-2008-molecular-spectroscopic-database-1ud8clpej3.pdf

The HITRAN 2008 molecular spectroscopic database

A doubling in global food demand projected for the next 50 years poses huge challenges for the sustainability both of food production and of terrestrial and aquatic ecosystems and the services they provide to society. Agriculturalists are the principal managers of global useable lands and will shape, perhaps irreversibly, the surface of the Earth in the coming decades. New incentives and policies for ensuring the sustainability of agriculture and ecosystem services will be crucial if we are to meet the demands of improving yields without compromising environmental integrity or public health.

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Agricultural sustainability and intensive production practices

https://cimss.ssec.wisc.edu/dbs/China2011/Day2/Lectures/MODIS_MOD13_NDVI_referenc.pdf

Overview of the radiometric and biophysical performance of the MODIS vegetation indices

Nitrogen is a key element controlling the species composition, diversity, dynamics, and functioning of many terrestrial, freshwater, and marine ecosystems. Many of the original plant species living in these ecosystems are adapted to, and function optimally in, soils and solutions with low levels of available nitrogen. The growth and dynamics of herbivore populations, and ultimately those of their predators, also are affected by N. Agriculture, combustion of fossil fuels, and other human activities have altered the global cycle of N substantially, generally increasing both the availability and the mobility of N over large regions of Earth. The mobility of N means that while most deliberate applications of N occur locally, their influence spreads regionally and even globally. Moreover, many of the mobile forms of N themselves have environmental consequences. Although most nitrogen inputs serve human needs such as agricultural production, their environmental conse- quences are serious and long term. Based on our review of available scientific evidence, we are certain that human alterations of the nitrogen cycle have: 1) approximately doubled the rate of nitrogen input into the terrestrial nitrogen cycle, with these rates still increasing; 2) increased concentrations of the potent greenhouse gas N 2O globally, and increased concentrations of other oxides of nitrogen that drive the formation of photochemical smog over large regions of Earth; 3) caused losses of soil nutrients, such as calcium and potassium, that are essential for the long-term maintenance of soil fertility; 4) contributed substantially to the acidification of soils, streams, and lakes in several regions; and 5) greatly increased the transfer of nitrogen through rivers to estuaries and coastal oceans. In addition, based on our review of available scientific evidence we are confident that human alterations of the nitrogen cycle have: 6) increased the quantity of organic carbon stored within terrestrial ecosystems; 7) accelerated losses of biological diversity, especially losses of plants adapted to efficient use of nitrogen, and losses of the animals and microorganisms that depend on them; and 8) caused changes in the composition and functioning of estuarine and nearshore ecosystems, and contributed to long-term declines in coastal marine fisheries.

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Human alteration of the global nitrogen cycle: sources and consequences

https://harvardforest.fas.harvard.edu/sites/harvardforest.fas.harvard.edu/files/publications/pdfs/Currie_ForestEco&Manag_2004.pdf

Redistributions of 15N highlight turnover and replenishment of mineral soil organic N as a long-term control on forest C balance

Carbon-nutrient interactions are identified as important topics for ecological research in the 1980s. The linkages between carbon and nutrients during plant litter decay are the focus of this paper. A recently developed model for estimating the maximum net immobilization potential in decomposing litter is reviewed. The factors that control the magnitude of nitrogen immobilization are considered using the model. Key research questions about carbon-nitrogen interactions during plant litter decay are identified.

Nutrient Immobilization in Decaying Litter: An Example of Carbon-Nutrient Interactions

Leaf biomass is an important component of forest ecosystems. It is proportional to leaf area and primary production and also contains a major portion of a plants annual nutrient uptake and its contribution, through litter fall, to the forest floor. Thus leaf biomass reflects important developmental differences in both primary production and nutrient cycling between stands. While much information is avaialable for changes in leaf production over time in monospecific stands we know of no similar published data for a mixed-species temperate forest.

Leaf Production During Secondary Succession in Northern Hardwoods

Curtis (1959) showed that both climate and soils influence the composition of Wisconsin forests but he could not determine the relative effects of each. To determine the effects of soil properties on species composition, a wide variety of soil and community types is needed in a single climatic regime. Blackhawk Island is a 70-ha island in the Wisconsin River in southwestern Wisconsin which supports a wide variety of forest communities on several soil types, including some communities and soils usually found only in northern Wisconsin. The soils form a gradient of moisture and N availability. Pines (Pinus strobus L., P. resinosa Ait.) are dominant on sandy soils with low N mineralization and nitrification; oaks (Quercus borealis Michx., Q. alba L.) are dominant on sandy clay-loams and silt loams with moderate N mineralization and nitrification, and sugar maple (Acer saccharum Marsh.) is dominant on silty clay-loams with high N mineralization and nitrification. Species replacement along this gradient results in an increase in continuum index that is strongly related to the increase in N mineralization, nitrification, silt + clay content and P content of the soils, but less strongly related to other soil properties. Two communities not on this gradient are: (1) aspen (Populus grandidentata Michx.) on plowed silt loam with low N mineralization and nitrification and (2) hemlock (Tsuga canadensis (L.) Carr.) on organic soil with low N mineralization and nitrification. The soil textures are a result of the geologic history of the island. The distribution of communities is therefore a result of ecological processes which are working within the framework of a soil texture gradient determined by the geologic history of the island. INTRODUCTION In a gradient analysis of the vegetation of Wisconsin, Curtis and his co-workers (Curtis, 1959; see Literature Cited for further references) showed that the geographical distribution of species and communities throughout the state was related to both climate and soil. Because of the large geographic area covered and because of the relationship between climate and soils, it was difficult to determine which had more influence on the distributions and community relationships of species. Many factors varied along a climatic gradient from southwestern to northeastern Wisconsin. For example, the distribution of communities was similar along both a pH gradient and a mean July temperature gradient because of coincident but independent changes in bedrock chemistry and July temperature. In addition, the importance of several species in the communities, such as sugar maple, increased with both decreasing temperature and increasing soil moisture. More recently, Peet and Loucks (1977) showed that the composition of southern Wisconsin forests is related to a moisture-nutrient gradient and to a successional gradient, but did not specify the important nutrient(s) involved. In order to determine more precisely the effect of soils or climate on vegetation distribution, it is desirable to find sites in which one of the factors is held constant, or nearly so, while the other varies. The purpose of this paper is to examine changes in species composition of several forests along a gradient of soil types under equivalent climatic conditions.

Geology, soils and vegetation of Blackhawk Island, Wisconsin.

It has long been recognized that composting yields a large quantity of thermal energy, which is normally lost to the surrounding environment as heat. Efforts to recover this heat using compost heat recovery systems (CHRSs) have been sporadic. Literature on the subject is also disjointed. To summarize the research that has been conducted, the authors performed an extensive literature review, covering publications in scientific journals, trade magazines, books, theses, and published reports. A focus on CHRS design and heat recovery rates is presented. The review covers 45 CHRSs in 16 different countries, ranging from simple hotbeds used in China 2000 years ago, to advanced super-thermal conductor heat pipe systems in 2016. Heat recovery rates varied significantly, with no predictable trend among the 45 systems. Recovery rates averaged 1895 kJ/hr (1159 kJ/kg DM) for lab-scale systems, 20,035 kJ/hr (4302 kJ/kg DM) for pilot-scale systems, and 204,907 kJ/hr (7084 kJ/kg DM) for commercial systems.

John D. Aber

Papers

Redistributions of 15N highlight turnover and replenishment of mineral soil organic N as a long-term control on forest C balance

Nutrient Immobilization in Decaying Litter: An Example of Carbon-Nutrient Interactions

Leaf Production During Secondary Succession in Northern Hardwoods

Geology, soils and vegetation of Blackhawk Island, Wisconsin.

Heat Recovery from Composting: A Comprehensive Review of System Design, Recovery Rate, and Utilization