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This chapter discusses the history and development of mapping and classification of vegetation, first describing early mapping efforts of California's vegetation in the late 1800s and in the early 1900s. It then describes the advances in mapping and classification of vegetation that took place in California. For vegetation mapping, these include the use of satellite-based remote sensing techniques by the U.S. Forest Service Remote Sensing Lab in Sacramento and the development of detailed maps based on the interplay of Geographic Information Systems (GIS) analysis, air-photo interpretation, and extensive field checking. The Manual of California Vegetation (MCV) heralded an increased focus on quantitative descriptive techniques, which led to the current standardized state, national, and international vegetation classification systems. Today, field-based vegetation sampling and the classification scheme is integrated with a detailed GIS-based map of the vegetation using the new standards for quantification of vegetation set forth in the MCV and the National Vegetation Classification system.

There are two distinct categories of remotely sensed data: satellite data and aerial data or photographs. Unlike aerial photographs, satellite data have been routinely available for most of the earth’s land areas for more than two decades and therefore are preferred for reliably monitoring global vegetation conditions. Satellite data are the result of reflectance, emission, and/or back scattering of electromagnetic energy from earth objects (e.g., vegetation, soil, and water). The electromagnetic spectrum is very broad, and only a limited range of wavelengths is suitable for earth resource monitoring and applications. The gaseous composition (O2, O3, CO2, H2O, etc.) of the atmosphere, along with particulates and aerosols, cause significant absorption and scattering of electromagnetic energy over some regions of the spectrum. This restricts remote sensing of the earth’s surface to certain “atmospheric windows,” or regions in which electromagnetic energy can pass through the atmosphere with minimal interference. Some such windows include visible, infrared, shortwave, thermal, and microwave ranges of the spectrum. The shortwave-infrared (SWIR) wavelengths are sensitive to moisture content of vegetation, whereas the thermal-infrared region is useful for monitoring and detecting plant canopy stress and for modeling latent and sensible heat fluxes. Thermal remote sensing imagery is acquired both during the day and night, and it measures the emitted energy from the surface, which is related to surface temperatures and the emissivity of surface materials. This chapter focuses on the contribution of visible and infrared wavelengths to global drought monitoring, and chapter 6 discusses visible, infrared, and thermal wave contributions. Under microwave windows, the satellite data can be divided into two categories: active microwave and passive microwave. Chapters 7 and 8 describe applications of passive and active microwave remote sensing to drought monitoring, respectively. Early use of satellite data was pioneered by the Landsat series originally known as the Earth Resource Technology Satellite (ERTS; http://landsat7.usgs.gov/index.php). Landsat was the first satellite specifically designed for broad-scale observation of the earth’s land surface.

As biodiversity, ecosystem function, and ecosystem services become more closely linked with human well-being at all scales, the study of ecology takes on increasing social, economic, and political importance. However, when compared with other disciplines long linked with human well-being, such as medicine, chemistry, and physics, the technical tools and instruments of the ecologist have generally lagged behind those of the others. This disparity is beginning to be overcome with the increasing use of biotelemetric techniques, microtechnologies, satellite and airborne imagery, geographic information systems (GIS), and both regional and global data networks. We believe that the value and efficiency of ecosystem studies can advance significantly with more widespread use of existing technologies, and with the adaptation of technologies currently used in other disciplines to ecosystem studies. More importantly, the broader use of these technologies is critical for contributing to the preservation of biodiversity and the development of sustainable natural resource use by humans. The concept of human management of biodiversity and natural systems is a contentious one. However, we assert that as human population and resource consumption continue to increase, biodiversity and resource sustainability will only be preserved by increasing management efforts—if not of the biodiversity and resources themselves, then of human impacts on them. The technologies described in this chapter will help enable better management efforts. In this context, biodiversity refers not only to numbers of species (i.e., richness) in an arbitrarily defined area, but also to species abundances within that area. Sustainability refers to the maintenance of natural systems, biodiversity, and resources for the benefit of future generations. Arid-land grazing systems support human social systems and economies in regions all over the world, and can be expected to play increasingly critical roles as human populations increase. Further, grazing systems represent a nexus of natural and domesticated systems. In these systems, native biodiversity exists side by side with introduced species and populations, and in fact can benefit from them.

Climate is one of the most important determinants of biotic structure and function in the alpine. High winds and low temperatures are defining elements of this ecosystem, requiring adaptations of the alpine biota. Interaction between topography and snowcover strongly influences spatial heterogeneity of microclimate, which in turn influences and is influenced by the distribution of vegetation. For nearly 50 years investigators have used Niwot Ridge to examine and document the climate and its interaction with the biota of the alpine tundra. This chapter reviews some of the many findings of these ongoing bioclimatic investigations. Climate studies started on Niwot Ridge in October 1952 when Professor John W. Marr and his students set up a transect of climate stations across the Front Range between Boulder and the Continental Divide (Marr 1961). There were originally 16 stations in groups of four representing different slope exposures in what he defined as the Lower and Upper Montane Forest, the Subalpine Forest, and the Alpine Tundra ecosystems of the Front Range. After 1 year, the network was reduced to four stations, called Al, Bl, Cl, and Dl, which all had ridge-top locations and ranged from lower montane (Al) to high alpine (Dl). From time to time, these stations were supplemented by other stations that supported particular studies. This was especially true during the International Biological Programme years in the early 1970s when focus on work on the Saddle research site of the Ridge began. Following the establishment of Niwot Ridge and Green Lakes Valley as a Long-Term Ecological Research (LTER) site in 1980, even more intensive climatological work has been conducted. The construction of the Tundra Laboratory in August 1990 facilitated intensive winter climatological studies. Geographical locations and elevational data on most of the stations has been provided by Greenland (1989) and is also found in the LTER electronic database (http://culter.colorado.edu/). The climate of Niwot Ridge is characterized by large seasonal and annual variability with very windy and cold winters, wet springs, mild summers, and cool, dry autumns.

Contemporary warfare has been significantly transformed by the promotion and implementation of unmanned aerial vehicles (or drones) into global military operations. Networked remote sensory vision and the drones’ capability to carry deadly missiles entail and facilitate increasingly individualised, racialised, and necropolitical military practices conceptualised as ‘surgical strikes’ or ‘targeted killings’, all in the name of ‘counterinsurgency’. In the absence of publicly accessible documentations of ‘drone vision’, images of drones themselves constitute what is arguably one of the most contested iconographies of the present. The ethical and legal problems engendered by the virtualisation of violence and the panoptical fantasies of persistent vision and continuous threat interfere with the commercial interests and the publicised ideas of ‘clean’ warfare of the military-industrial-media complex. Drones have become a fetishised icon of warfare running out of human measure and control and are henceforth challenged by activist strategies highlighting the blind spots and victims of their deployment.

One of the remarkable sides of the fast and intense transformation of the Amazon in recent decades has been the coupled process of urbanization and forest resurgence taking place in the Amazon estuary. This chapter provides an analysis of the region's forest-based economy of relevance to rural and urban residents, and the emergence of new forms of household and social networks linking rural and urban spaces in the Amazon estuary. These analyses benefit from long-term ethnographic work in the Amazon estuary, particularly the municipality of Ponta de Pedras (Pará State), primary and secondary remote sensing of forest change, archival and census data from 1950 to 2000, and recent household surveys among seven rural communities (264 households and 2,168 individuals) and three urban areas (100 urban households and 1,063 individuals). The article concludes by reflecting on the implications of these processes to the understanding of forests, livelihoods, and urbanization in the Amazon.

Digital archives offer the investigator an up-to-date analysis of an extensive and specialized literature. Periodic revisions are reported in the open literature and it seems unlikely that future investigators will attempt to use any other source where archives can provide the required data. For this reason, we shall confine our comments on permitted vibration-rotation transitions to describing the AFGL tape contents, but we shall add two areas not contained in it: first, electronic bands, and second, the related topics of forbidden transitions, collision-induced transitions, and polymer spectra. The AFGL tape lists data on one important set of electronic transitions, those giving rise to the near-infrared atmospheric bands of molecular oxygen. These bands behave in the same way as vibration rotation bands, except for the frequency displacement caused by the change in electronic energy and the symmetry conditions imposed by the electronic wave functions. Other electronic transitions usually involve larger differences between energy levels and cannot be understood as completely as the lower energy, vibrational and rotational transitions. Fortunately, visible and ultraviolet bands of importance for atmospheric problems are less complicated than vibration—rotation bands and they are usually less affected by state parameters. Atmospheric absorption calculations in the visible and ultraviolet spectrum are commonly made on the basis of empirical data without requiring the level of understanding developed in Chapters 3 and 4 for vibration-rotation bands. The altitude of unit optical depth for ultraviolet atmospheric bands is illustrated in Fig. 5.1. The intensity of solar radiation falls off rapidly with decreasing wavelength in the spectral region shown (the irradiance at 2000 Å compared to that at 3000 Å is 10-2 whereas at 1000 Å it is 10-5, see Appendix 9). For heating rate calculations at altitudes less than 100km, only O2 and O3 are important, except under special conditions when the atmosphere contains large amounts of volcanic aerosols, or polar stratospheric clouds at high latitudes. All of the absorptions shown in Fig. 5.1 are important for other reasons that do not directly concern us here.

One of the goals of logical analysis is to construct mathematical models of various practices of deductive inference. Traditionally, this is done by means of giving semantics and rules of inference for carefully specified formal languages. While this has proved to be an extremely fruitful line of analysis, some facets of actual inference are not accurately modeled by these techniques. The example we have in mind concerns the diversity of types of external representations employed in actual deductive reasoning. Besides language, these include diagrams, charts, tables, graphs, and so on. When the semantic content of such non-linguistic representations is made clear, they can be used in perfectly rigorous proofs. A simple example of this is the use of Venn diagrams in deductive reasoning. If used correctly, valid inferences can be made with these diagrams, and if used incorrectly, they can be the source of invalid inferences; there are standards for their correct use. To analyze such standards, one might construct a formal system of Venn diagrams where the syntax, rules of inference, and notion of logical consequence have all been made precise and explicit, as is done in the case of first-order logic. In this chapter, we will study such a system of Venn diagrams, a variation of Shin’s system VENN formulated and studied in Shin [1991] and Shin [1991a] (see Chapter IV of this book). Shin proves a soundness theorem and a finite completeness theorem (if ∆ is a finite set of diagrams, D is a diagram, and D is a logical consequence of ∆ , then D is provable from ∆ ). We extend Shin’s completeness theorem to the general case: if ∆ is any set of diagrams, D is a, diagram, and D is a logical consequence of ∆. then D is provable from ∆. We hope that the fairly simple diagrammatic system discussed here will help motivate closer study of the use of more complicated diagrams in actual inference.