Ecological principles and guidelines for managing the use of land

The many ways that people have used and managed land throughout history has emerged as a primary cause of land‐cover change around the world. Thus, land use and land management increasingly represent a fundamental source of change in the global environment. Despite their global importance, however, many decisions about the management and use of land are made with scant attention to ecological impacts. Thus, ecologists\u27 knowledge of the functioning of Earth\u27s ecosystems is needed to broaden the scientific basis of decisions on land use and management. In response to this need, the Ecological Society of America established a committee to examine the ways that land‐use decisions are made and the ways that ecologists could help inform those decisions. This paper reports the scientific findings of that committee. Five principles of ecological science have particular implications for land use and can assure that fundamental processes of Earth\u27s ecosystems are sustained. These ecological principles deal with time, species, place, disturbance, and the landscape. The recognition that ecological processes occur within a temporal setting and change over time is fundamental to analyzing the effects of land use. In addition, individual species and networks of interacting species have strong and far‐reaching effects on ecological processes. Furthermore, each site or region has a unique set of organisms and abiotic conditions influencing and constraining ecological processes. Disturbances are important and ubiquitous ecological events whose effects may strongly influence population, community, and ecosystem dynamics. Finally, the size, shape, and spatial relationships of habitat patches on the landscape affect the structure and function of ecosystems. The responses of the land to changes in use and management by people depend on expressions of these fundamental principles in nature. These principles dictate several guidelines for land use. The guidelines give practical rules of thumb for incorporating ecological principles into land‐use decision making. These guidelines suggest that land managers should: (1) examine impacts of local decisions in a regional context, (2) plan for long‐term change and unexpected events, (3) preserve rare landscape elements and associated species, (4) avoid land uses that deplete natural resources, (5) retain large contiguous or connected areas that contain critical habitats, (6) minimize the introduction and spread of nonnative species, (7) avoid or compensate for the effects of development on ecological processes, and (8) implement land‐use and management practices that are compatible with the natural potential of the area. Decision makers and citizens are encouraged to consider these guidelines and to include ecological perspectives in choices on how land is used and managed. The guidelines suggest actions required to develop the science needed by land managers

Ecological guidelines for land use and management

This volume applies ecological principles and guidelines to understand past and current land use and land management; and more importantly, endeavors to promote more ecologically sound approaches to future land use and management decisions. The volume incorporates case studies from a wide variety of disciplines and perspectives. The case studies explore past and current land use decisions, on both public and private lands, and include practical approaches and tools for land-use decision-making. Perhaps the most important feature of the book is the linking of ecological theory and principle with applied land use decision-making - the theoretical and empirical are joined through concrete case studies of actual land use decision-making processes. In this volume, readers will find a statement of fundamental ecological principles that are relevant for land use planning and management, coupled with multiple in-depth explorations of the application of these principles in action. In addition, most case studies describe specific tools and approaches for incorporating endeavors to join fundamental ecological knowledge with cutting edge application in order to both educate and provide concrete guidance for decision-making

New Light on the Relationship between the Montecitorio Obelisk and Ara Pacis of Augustus

The article takes as its point of departure recent work (Frischer forthcoming) critiquing the theory of Edmund Buchner about the relationship of the gnomonical instrument known as the Horologium Augusti and the Ara Pacis Augustae. As a result of this critique, the Montecitorio Obelisk could be situated with greater precision on the map of the city. A computer simulation showed that Buchner erred in positing that the shadow of the Montecitorio Obelisk went into the center of the Ara Pacis on Augustus’ birthday. In this article, computer simulations are used to develop a post-Buchnerian interpretation of the relationship of the obelisk and altar. Over 230 hitherto unrecognized solar and shadow alignments are reported. The first part of the article defines four zones around the monuments where the solar and shadows observations were made. In the second part of the article, specialists interpret the significance of the annual solar and shadow spectacle from various points of view. The conclusion synthesizes the results, arguing that the monuments were intentionally aligned and situated in order to propagate the same message as the one inscribed on two sides of the Montecitorio Obelisk [CIL 6.702 = ILS 91]: that Augustus was a devoted worshipper of the sun god (Sol), who brings Rome victory in war, peace, and prosperity through his earthly representative, the emperor

Excess Nitrogen in the U.S. Environment: Trends, Risks, and Solutions

Thanks largely to the early 20th century invention of synthetically manufactured nitrogen (N) fertilizers, the growing human population is, on average, better nourished now than ever before in human history. About 40 to 60% of the current human population depends upon crops grown with synthetic nitrogen fertilizer. Unfortunately, this impressive advance in agricultural productivity and human nutrition has come at a high price of environmental degradation and human health risks from pollution. A large fraction of nitrogen fertilizer applied to cropland - often over half - is not used by the crops and is lost to air, water, and downstream and downwind habitats, polluting landscapes and waterscapes. At the same time, energy, transportation, and industrial sectors also emit nitrogen pollution into the air through increasing use of fossil fuels. In 1997, the first Issue in Ecology described the magnitude, causes, and consequences of these human alterations of the nitrogen cycle, documenting how humans have more than doubled the amount of reactive nitrogen (see Glossary for definitions) annually in circulation in the terrestrial biosphere. Several of these trends have continued along with increasing numbers of people, including improving human diets in the developing world, increasing global use of fertilizers, increasing atmospheric concentrations of the potent greenhouse gas nitrous oxide, and increasing eutrophication of aquatic and terrestrial habitats. Fifteen years later, we now ask: "Has scientific awareness of the growing problems of nitrogen pollution fostered progress in finding solutions?"