Man's Impact Research Articles

The Attic landscape throughout the centuries and its human degradation

Characteristic of the Attic landscape is its great diversity. There are many mountains, plains, valleys, basins and hills. The geological background and the climate are varied. Man's impact on this landscape has a long history, because there were settlements and intense grazing even during the prehistoric period. There were, also, cultivations, especially olive orchards. The history of human impact on the Attic landscape is divided into different phases of landscape modification. The natural ecosystems of Attica and their present status are considered.

Environmental impact studies on marine communities: Pragmatical considerations

Abstract The measurement of changes in the structure of natural marine communities is widely used for the detection and monitoring of man's impact on the sea. Such studies are almost always a compromise between the scientific ideal and political, financial and logistical constraints. This paper considers a number of these constraints, suggests some possible solutions, and discusses the consequences (in terms of loss of information) of adopting strategies which might be considered suboptimal.Identification of all organisms in a community to species level is a major time and cost constraint. Many recent studies have shown that very little information is lost by working at a taxonomic level higher than species (e.g. family or even phylum). This implies a functional coherence of species within each higher taxon. Indeed, there are theoretical reasons, and some empirical evidence, for supposing that community responses to human perturbations may be more easily detected above the noise of natural variability by working at high taxonomic levels.Many environmental impacts, for example oil spillages from tankers, are accidental and it is unusual to have the luxury of a time‐series of data from the site prior to the incident. Good spatial control samples may also be difficult to obtain in a heterogeneous environment. Absolute rather than comparative measures of community degradation are valuable in this context. Methods which fall into this category include comparisons of community structure with some theoretical expectation or with empirical‘training’ data, comparing attributes of community structure that respond differently to perturbation, or identifying highly conservative properties of unperturbed communities that are modified in a predictable way by perturbation.All studies are selective with regard to which components and attributes of the biota should be investigated. The choice frequently depends on local expertise and research interests, rather than on an objective decision about what biological data are most appropriate for the problem in hand. The paper concludes by a discussion of the relative merits of the various alternatives.

Global warming and the evaluation of fuel substitution strategies: on why policy should be left to the politicians

It is often taken for granted that substituting natural gas for oil will serve to reduce the greenhouse emissions of the energy sector, and executing such substitution is thus seen as a coherent policy response to the problem of global warming. In this paper we argue that such a policy is ill–founded because the supposition on which it rests is based on an incomplete consideration of the comparative pollution characteristics of the two fuels. The consideration is incomplete in two senses: (i) authors focus on emissions of carbon dioxide to the virtual exclusion of the secondary greenhouse gases, and (ii) attention is paid only to those emissions which result from fuel combustion, rather than to emissions from the entire fuel cycle (including extraction, distribution and storage). In this paper we adopt a simple, empirical 'emissions–accounting' framework [28]. Using a range of plausible parameter values it is demonstrated that the 'greenhouse friendliness' ranking of natural gas and oil is highly ambiguous. We cite very recent engineering estimates of methane leakage associated with commercial natural gas distribution and go on to demonstrate that natural gas usage may result in the emission of more greenhouse gases than oil usage. The ambiguity in the ranking is driven by two major uncertainties, one technological and one political. The most significant implication is that the resolution of the technical uncertainty surrounding the greenhouse effect and man's impact upon global climate will not be sufficient to determine what constitutes an effective policy response. The determination of policy will be an essentially political problem. Policy formulation and determination should, as the title suggests, be left to the politicians.

Floristic evaluation of anthropopressure zones in Warsaw With 5 Figures

AbstractIn the present work the results of floristic investigations conducted in Warsaw for over a period of 10 years were used. The city area was divided into 225 squares. Each square was assigned to one of the four anthropopressure zones A, B, C, D which were distinguished with respect to the gradually decreasing intensity and duration of man's impact. The work attempts to find the best floristic reflection of the anthropopressure zones. For each square both the floristic lists and the previously defined complex indices of flora synanthropization were analyzed.The use of complex indices instead of entire flora is associated with the inevitable reduction of informations which may be selected intentionally.Seven different ways of classifying the squares according to the anthropopressure intensity: A‐B‐C‐D, A‐B‐(CD), A‐(BC)‐D, (AB)‐C‐D, (AB)‐(CD), A‐(BCD), (ABC)‐D were compared with the floristic classifications. These classifications were compiled using the cluster analysis in which both the entire flora and complex indices were used.Assessing the similarities between classifications it is possible to draw conclusions about the sensitiveness of indices and flora as a whole to change due to man. Floristic value of the borders between the anthropopressure zones A‐(BCD) or between (AB)‐(CD) is the greatest. In general, the indices reflect the anthropopressure zones better than the entire flora.

AGU acquires Springer‐Verlag Series

AGU has acquired Springer‐Verlag's (New York) Coastal and Estuarine Studies book series. This acquisition adds thirty‐nine volumes to AGU's own Coastal and Estuarine Sciences book series.Coastal and estuarine science is a rapidly growing area of research driven in part by an increasing awareness of man's impact on the coastal zone, and the importance in understanding its delicate ecosystems. This area of study enhances AGU's initiatives in interdisciplinary research. Particular emphasis is being placed on understanding the complex interactions between the physical, geological, chemical, and biological aspects of marine science.

The DECAFE experiments: Overview and meteorology

The objective of the Dynamique et Chimie de l'Atmosphère en Forêt Equatoriale (DECAFE) program is to determine the influence of African tropics on atmospheric chemistry. Savannas and forests constitute the main ecosystems in this area. Because of the occurrence of biomass burning during the dry season, savannas of the northern and southern hemispheres are active sources of many constituents which are of interest to atmospheric chemistry. The rain forest, with its important biomass activity is also a source or sink for gases and aerosols. Man's impact on this ecosystem is important since the rate of deforestation is about 0.5% per year. Furthermore, a general air motion from savanna regions toward the tropical rain forest is observable in most parts of Africa, leading to important interactions between the respective emissions of these two ecosystems. The DECAFE experiments presented in this issue were located in the Mayombe forest (southern Congo) and in the forest of the northen Congo. A study of rain chemistry was undertaken in 1986 in the Mayombe forest, then continued in the northern forest. In February 1988 a coordinated experiment was held in the tropical rain forest of the north, near Impfondo. The paper presents an overview of the general meteorological and climatological situation in the African tropics, a study of the climatological features of the sites, and a short description of the Impfondo experiment, which is the subject of most of the contributions to this special issue. The local meteorological situation during the time of the experiment is analyzed.

Global ecology priorities

An attempt to substantiate priorities of global ecology has been undertaken with an emphasis on two principal aspects: 1) heat balance of the Earth and anthropogenically induced redistribution of its components; 2) closed nature of global biogeochemical cycles. It has been shown that the ecological faith of the Earth depends first of all on biosphere dynamics disturbed by man's impact. The Global Change programmes worked out in the U.S. and France have been summarized to analyse their advantages and disadvantages. The principal conclusion is that further discussion is necessary, preferably at the UN level. The Second UN Conference on Environment and Development will opens such a possibility.

Protection of the natural environment in time of armed conflict

Since the early 1970s, the steady deterioration of the natural environment has given rise to widespread awareness of man's destructive impact on nature.This awareness of the vital importance for humanity of a healthy environment and the determined efforts of numerous environmental protection agencies have led over the years to the adoption of a large body of laws for the protection and preservation of the natural environment.

L'évolution tardiglaciaire et holocène des glaciers et de la végétation autour de l'Alpe d'Huez (Oisans, Alpes Françaises)

Abstract: Tardiglacial and Holocène evolution of glaciers and vegetation in the Alpe d'Huez area (Oisans, French Alps) The limited glaciation of the Rousses massif in the French northern Alps (lat. 45°N) may be explained in terms of the physical parameters of this mountain environment, the highest peak of which is the Pic Bayle (3465 m). Along its southwestern slopes, below the forward ice margins of the present glaciers, can be found several accumulations of glacial moraine. Through the study of pollens found in two post-glacial bogs and carbon 14 dating, it is possible to ascribe them to Tardiglacial and Holocène fluctuations. Since 14 000 BP, the main valleys in this part of the Alps have been free of ice. With the first temperate phases of the Tardiglacial period, alpine grasslands and trees appeared on the slopes between 1800 and 2000 m. During the Atlantic stage, a forest of birches and alders grew on the site of Alpe d'Huez, constituting a transitional belt between the coniferous sub- alpine forest and alpine grasslands. During the Roman period, about 2000 years ago, the forest was destroyed by man and the present land-scape of treeless grasslands became established. Over the past 2000 years, man's impact has been so great that today only the periglacial and glacial areas can be considered as true natural mountain environments. For this reason, the author suggests establishing a nature reserve in the north of the massif.

A 5-year scientific research programme for managing coastal seas

The management of coastal seas requires scientific knowledge to: (i) link inputs to resulting concentrations, (ii) distinguish between natural variability and man's impact, and (iii) predict long term trends. This knowledge incorporates: (i) movement and dispersion of both water and sediments, (ii) partitioning of contaminants between dissolved and particulate phases, (iii) successive exchange processes between river/estuary/coastal zone/sea/ocean and between sea/sea-bed and sea/atmosphere. The UK is presently mid-way into a 5-year, £15M oceanographic research programme in the North Sea involving the development of numerical models, systematic observations and fundamental research to fill gaps in basic knowledge. The programme will proceed through three stages, simulating physical, biological, chemical and sedimentological parameters: (i) over the well-defined annual seasonal cycle, (ii) over inter-annual variations, (iii) for long term trends. Long-term data sets are vital for such programmes, systematic marine monitoring programmes must be initiated, involving combinations of remote sensing, sea-truth moorings and coastal stations. This programme will be extended to consider the contribution to and effect from global pollution, specifically possible greenhouse effects such as rise in mean sea level and meteorological changes. The widespread impact of such phenomena emphasises the necessity for internationa co-operation in all aspects of these studies.

Factors controlling late Cenozoic continental margin growth from the Ebro Delta to the western Mediterranean deep sea

The Ebro continental margin sedimentation system originated with a Messinian fluvial system. This system eroded both a major subaerial canyon cutting the margin southeastward from the present Ebro Delta and an axial valley that drained northeastward down Valencia Trough. Post-Messinian submergence of this topography and the Pliocene regime of high sea levels resulted in a marine hemipelagic drape over the margin. Late Pliocene to Pleistocene glacial climatic cycles, drainagebasin deforestation, and sea-level lowstands combined to increase sediment supply, cause the margin to prograde, and create a regime of lowstand sediment-gravity flows in the deeper margin. The depositional patterns of regressive, transgressive and highstand sea-level regimes suggest that location of the sediment source near the present Ebro Delta throughout the late Cenozoic, southward current advection of sediment, and greater subsidence in the southern margin combined to cause generally asymmetric progradation of the margin to the southeast. Thicker, less stable deposits filling the Messinian subaerial canyon underwent multiple retrograde failures, eroded wide gullied canyons and formed unchanneled base-of-slope sediment aprons in the central margin area; other margin areas to the north and south developed a series of channel-levee complexes. On the basin floor, the formation of Valencia Valley over the Messinian subaerial valley and earlier faults led to draining of about 20% of the Ebro Pleistocene sediment from channel-levee complexes through the valley to prograde Valencia Fan as much as 500 km northeast of the margin. Thus, the Ebro margin has two growth directions, mainly southeastward during higher sea levels, and eastward to northeastward during lower sea levels. The northeastward draining of turbidity currents has produced unusually thin and widely dispersed turbidite systems compared to those on ponded basin floors. During the past few centuries, man's impact has exceeded natural controls on Ebro margin growth. Deforestation of the drainage basin more than doubled the normal Holocene sediment supply, and construction of dams then reduced the supply by 95%. This reduction of the past 50 years has caused erosion of the delta and contamination of bottom sediment because normal Holocene sediment discharge is not available to prograde the delta or help dilute pollutants.

Murettes et terrasses de culture dans les régions karstiques méditerranéennes

Stone-walls and land-terraces in the mediterranean karst areas. After analysis on the functions of stone-walls and terraces, the paper show many types of agrarian arrangement in limestone slopes and table-land, in rapport with the quality of soils, and in little karst depressions. They make up «agro-karstic landscapes». In the dolines and uvalas particularly, the contouring and removal of blocks give «anthropo-geomorphological forms». This researches are continued in the outline of I.G.U. Study Group on «Man's impact in Karst», now «Environmental Changes in Karst Areas».

Les risques naturels dans un espace montagnard : la Haute Ubaye

Abstract. - The Upper Ubaye valley represents a scarcely populated, isolated mountain cell with a rather small turnover of seasonal visitors. Due to its geological complexity, it can be considered as an actual «museum» of natural disasters. This article deals various types of such catastrophic phenomena, ancient natural disasters linked with post-glacial decompression, some rather unfrequent phenomena like a glacier outburst, and much more tremendous disasters, earthquakes and floods which twice caused severe damage to the valley. The mountain area concerned is constantly subject to natural hazards, such as avalanches and rockslides, that cause few deaths so long as there is no real increase in the visiting population. Those great slope equilibriums have recently been put to question, as a result of man's impact, together with too narrow a view on the actual nature of such natural equilibriums and on the limits that should be ascribed to human interference with an environment that appears to be fragile.

Satellite Earth Observations for Energy Resource Development and Environmental Management: ABSTRACT

Global change and growing needs for energy and other resources and their impact on the environment will be major international issues for the 1990s. Advanced international satellite earth observation systems during the 1990s will include systems for Japan (JERS, ADEOS), France (SPOT), Canada (Radarsat), Europe (ERS), India (IRS), and the U.S. (Landsat, NOAA, and N-POP). NASA's proposed advanced Earth Observing System (EOS/N-POP) will provide extensive satellite earth observations for resource development and global change studies for better environmental management. These satellites will produce tremendous volumes of digital electro-optical, microwave, and radar data creating a massive database for basic scientific and applied research for geology, agriculture, oceanography, meteorology, and environmental sciences. Database management and data access are major NASA and international issues under current review. Use of earth observations in energy and mineral resource exploration and development has become established during the last 20 years and will continue to expand with new information derived from these new satellite systems. US government environment global change research is being coordinated by the new interagency Committee on Earth Sciences (C.E.S.). The Geosat Committee, supported by resource industries who contribute to man's environmental impact and have a major stake in the C.E.S. research plan, ismore » working with the C.E.S. to establish industry-government-academia linkages for research in the broad global resource and environmental studies from space.« less

On the use of ecological prices and system-wide indicators derived therefrom to quantify man's impact on the ecosystem

Ecological prices and other system-wide, quantitative descriptors of ecosystem functioning are derived from the assumption that ecosystems allocate available resources efficiently among their components. However, ecological prices are not efficiency prices only, and using them does not require one to assume that the ecosystem is completely controlled by Man. The same prices balance flows of different biomasses in a multicomponent system. As such they play the role of exchange prices in a decentralized ecosystem. Properly defined with the help of ecological prices, the resulting ecosystem productivity is no less a significant indicator of ecosystem functioning than the national product is significant for assessing the functioning of an economy. Considerations of the values taken simultaneously by our proposed indicators and by their economic analogs are of much help in judging the desirability of projects with relatively mild environmental repercussions. These values are obtained from an integrated model of a system in which ecological and economic activities are intertwined. However, for the indicators to have an analytical meaning, the methodology should be applied to trace only those dynamic paths during which the system possesses unique, state-dependent, intensive properties. In other cases, a more comprehensive methodology - one which also pays due regard to the viability of the ecosystem - must supplement the analytical approach. This rather comprehensive methodology is scale-dependent and probabilistic in nature. While delineating relations between the structure of the system and its behavior, this method implies that efficiency and viability are two complementary rather than two commensurate attributes of a single entity. An outside observer may be guided by his own values in his attempts to weigh these features, but no inherent property of the system exists that supports his values unequivocally. Nevertheless, this paper proposes an approximation to overcome this difficulty and to estimate a quantitative limit to the rate of substitution between productivity and viability. Such a limit is also an intensive property of the simulated system, and the estimation of its value is shown to be crucial for studying the vulnerability of real ecosystems to severe Man-made disturbances.

Climate and water resources

Abstract River runoff and the resulting water resources which provide the needs of mankind for fresh water are subject to variations in space and time mainly depending on the space and time variability of climate characteristics. Thus there are close interrelations between the problems of the provision of fresh water and the problems of both natural and anthropogenic changes in climate. Moreover, these interrelations are characterized by specific features both under natural conditions and during a period of man's intensive impact on water resources. The problem of these interrelations has acquired a particular scientific and practical importance during recent years in which climatologists have attempted to predict global anthropogenic changes in climate for the near future, changes unknown on our plant for millennia. The present paper has been prepared mainly on the basis of research results obtained at the State Hydrological Institute in Leningrad. It describes the global interrelations between climatic ...

Attitudes towards the environment in Switzerland, 1880–1914

Compared with our own time, very caring in matters concerning the environment, the end of the nineteenth century and the beginning of the twentieth century can also be seen as a period already very sensitive toward the negative consequences of man's impact on the natural environment. In Switzerland, in particular, rapid transformations of the mountain landscape, hitherto intact, caused some reactions. This article shows that, contrary to what occurs today, preoccupation with the landscape around 1900 did not justify itself by scientific arguments, even if the concepts already existed. It was aesthetic and patriotic arguments which won the day in speeches by the defenders of the landscape. The landscape which some wished to protect had been created according to the norms and social values of the society of that period. The ideological implications are essential in order to understand the emergence of a sensitivity toward the environment, be it in 1900 or today.

Evolutionary analysis of the contemporary landscape sphere of the earth and prognosis

Recently, the dynamics of the landscape sphere over different time scales have become the focus of increased attention. The origin of the landscape sphere, monitoring of the changes which the sphere has undergone and is undergoing, and prediction of future events, have been combined into the new discipline of ‘evolutionary geography’. The structure of the landscape sphere is mainly controlled by the hydrothermal regime, in particular by solar energy input, spatial distribution of heat, and heat and moisture transport over the earth's surface. The present-day landscape sphere is characterized by belts of temperate and tropical forests in a polyzonal system. The natural course of climatic change would result in the future transformation of the landscape sphere to a cryohyperzonal system dominated by open tundra-steppes, steppes, and deserts. Anthropogenic modification of the climate, however, is likely to significantly disturb this pattern. Efforts to assess future changes are centered around determination of paleoecological regimes, both prior to and during the earlier phases of anthropogenic modification. The main process of man's impact on the zonal structure of the landscape sphere is deforestation, which will lead to an artificially-created hyperzonal system dominated by warm temperatures and open areas. If the prognosis of global warming and permafrost degradation is realized, the future of the landscape sphere must be viewed apprehensively.

Quasi-equilibrium in Holocene climatic change

To understand man's impact on the environment we should consider the long-term record. Within the Holocene epoch (approximately the last 10 ka), often regarded as having a uniformly mild ‘interglacial-type’ of climate, infrequent but violent fluctuations have disturbed this uniformitarian ideal. A quasi-equilibrium is maintained, however, by powerful feedback mechanisms. The precise nature of both the disturbance-forcing functions and the recovery mechanisms urgently requires study on an interdisciplinary basis, calling for a common-front approach by historians (for the best time scale), by geologists (for establishing the paleoecological and paleogeographical conditions by means of isotopic, sedimentological and stratigraphic studies), and by climatologists (for modelling the meteorological, synoptic conditions that characterize the varied events). Five non-linear forcing agents may be considered in a framework of working hypotheses to help explain the climatic departures: (1) Volcanic eruptions (dust veils and aerosols); (2) lunar and luni-solar tidal effects (variable standing waves in atmospheric pressure, modulation of ocean tides and currents); (3) terrestrial spin-rate and axial tilt (with secular change in precession, the 18.6 year axial rotation and the 1.2 year Chandler wobble); (4) oceanographic and glacial lag factors (influencing the chronology of latitudinal heat transfer; (5) solar radiation modulation of two principal types affecting the corpuscular pulses (solar flares), and the electromagnetic radiation (sunspot and Gleissberg cycles). This paper addresses particularly the last variable because this is the most neglected, and because new information has now become available thanks to new computer-based data sources.

Vegetational history of Carbury Bog (Co. Kildare, Ireland) during the last 850 years and a test of the temperature indicator value of 2H/1H measurements of peat samples in relation to historical sources and meteorological data

SUMMARYA palynological study of contiguous samples of the upper 128 cm of Carbury Bog, Co. Kildare, Ireland, showed details of the fluctuating human impact on the vegetation during the last c. 850 years. During the period of c. 1130–1440 A.D. the landscape around Carbury Bog was still dominated by forest. During the second half of the 15th century there was a considerable reduction of the forested area, reflected in the pollen diagram. The commercial exploitation of the forest during the 17th century resulted in almost complete deforestation. The pollen records for the 18th century vegetation show a rise in the curves of Pinus, Fraxinus and Fagus as a consequence of planting of these trees.Apart from pollen many other palynomorphs (‘Types’, a.o. fungal spores and rhizopods) were recorded. The spectrum of Types appeared to be comparable with the Type spectrum of continental raised bogs. The results of the macrofossil analysis in combination with the indicator values of some Types were used in a detailed reconstruction of the local vegetation succession and the changes in hydrological and trophic conditions. The disappearance of Sphagnum imbricatum during the late medieval period possibly was caused by the increased influx of dust, as a consequence of man's impact on the environment around the bog. The recent importance of S. magellanicum as a peat forming species is possibly the effect of an increased atmospheric deposition of nitrate.Parallel to the analysis of micro‐ and macrofossils a sample series from the same monolith was analysed for the ratio of the stable isotopes 2H and 1H. Theoretically the 2H/1H ratio in cellulose of peat‐forming plants should be indicative for palaeotemperatures, but, apart from a temperature dependent signal, this ratio is also strongly related to specific characteristics in the isotopic behaviour of different peat forming species. The overall fractionation is a complex function of climatic and plant‐physiological parameters.In the present study the results of the 2H/1H measurements were compared with Lamb's palaeoclimatic data derived from historical sources and meteorology. The 2H/1H ratios of Carbury Bog appeared to be negatively correlated with the medieval climatic optimum, the Little Ice Age and the subsequent phase of warming climate. There is an obvious relationship between the 2H/1H ratio and the local succession of peat forming taxa and, as a consequence, with strictly local hydrological and trophic conditions. The present study shows that a climatic signal in the 2H/1H ratio of peat samples is completely dominated by the direct effects of the spectrum of plants. In addition, the variation in the duration of the growing season in different climatic periods may have had a considerable influence on the 2H/1H ratio of the peat‐forming plants.