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Conversion of natural habitats into agricultural and industrial landscapes, and ultimately into degraded land, is the major impact of humans on the natural environment, posing a great threat to biodiversity. The emerging discipline of restoration ecology provides a powerful suite of tools for speeding the recovery of degraded lands. In doing so, restoration ecology provides a crucial complement to the establishment of nature reserves as a way of increasing land for the preservation of biodiversity. An integrated understanding of how human population growth and changes in agricultural practice interact with natural recovery processes and restoration ecology provides some hope for the future of the environment

One of the most important binding agents for forming stable aggregates is a soil organic matter (SOM), which can be retained in various size fractions of aggregates. If aggregates are water-resistant, they retain more carbon. Therefore, the aim of this study was to evaluate the stability of aggregates and their ability of carbon sequestration in different soil types and soil management systems in Slovakian vineyards. The highest content of water-stable macro-aggregates (WSAma) was determined in Cambisols, and the lowest in Fluvisols. The highest content of WSAma (size fraction 0.5–3 mm) was determined in Chernozems, decreasing within the following sequence: Fluvisols > Leptosols > Cambisols > Luvisols. The soil type had a statistically significant influence on the re-distribution of soil organic matter in size fractions of water-stable aggregates. The highest content of SOM in water-stable aggregates of the vineyards was determined in grassy strips in-between the vineyard rows in comparison to intensively cultivated rows of vineyard. The highest values of carbon sequestration capacity (CSC) in WSAma were found in Cambisols > Leptosols and the lowest values of CSC were in Fluvisols. The micro-aggregates represented a significant carbon reservoir for the intensively cultivated soils (rows of vineyard). On the other hand, increasing of macro-aggregates (size fraction 0.5–3 mm) was characteristic for grassland soils (between the rows of vineyard).

Spatially explicit population models are becoming increasingly useful tools for population ecologists, conservation biologists, and land managers. Models are spatially explicit when they combine a population simulator with a landscape map that describes the spatial distribution of landscape features. With this map, the locations of habitat patches, individuals, and other items of interest are explicitly incorporated into the model, and the effect of changing landscape features on population dynamics can be studied. In this paper we describe the structure of some spatially explicit models under development and provide examples of current and future research using these models. Spatially explicit models are important tools for investigating scale-related questions in population ecology, especially the response of organisms to habitat change occurring at a variety of spatial and temporal scales. Simulation models that incorporate real-world landscapes, as portrayed by landscape maps created with geographic information systems, are also proving to be crucial in the development of management strategies in response to regional land-use and other global change processes. Spatially explicit population models will increase our ability to accurately model complex landscapes, and therefore should improve both basic ecological knowledge of landscape phenomena and applications of landscape ecology to conservation and management.

Harmful impacts of floods are the result of an interaction between extreme hydrological events and environmental, social, and economic processes. Flood management should consider many diverse aspects and influences and an integrated approach to flood management therefore plays an important role. In order to make an analysis and provide an adequate flood management, it is necessary to bring together a team comprising experts e.g. from the fields of hydrology and water resources, nature protection, risk management, human security, municipal administration, economics, and land use. Estimates by experts can serve finding solutions to given YES/NO problems, and estimating the value of specific attributes or parameters. It is not easy to adopt the solution which represents the best possible agreement among the participating experts, since experts and other participants can represent diverse standpoints. In particular, landowners and leaseholders upstream a catchment are often in a different position than the members of the municipal flood control committee downstream in a city with a high inhabitancy. In order to measure and evaluate the level of agreement between experts and landowners, a newly developed method for assessing the level of agreement and the τ-agreement value was applied. The aim of the present paper is to illustrate the use of a fuzzy-group-agreement decision-making procedure of this kind, involving a broad range of standpoints in a case study of the Zdravá Voda catchment, Žarošice, Czech Republic. This illustration has been made by comparison of hydrological model scenarios with the experts’ decision. The method used in the paper applied towards aggregating expert proposals expressed as fuzzy quantities to propose a binary solution to estimate a decisive parameter numerical value. The decision achieved for the Zdravá Voda catchment was that the efficiency of structural measures (polder) was superior over the non-structural measures (replacement of the arable land by grassland).

Auction theory is used to analyze the potential benefits of auctions in allocating contracts for the provision of nonmarket goods in the countryside. A model of optimal bidding for conservation contracts is developed and applied to a hypothetical conservation program. Competitive bidding, compared to fixed-rate payments, can increase the cost effectiveness of conservation contracting significantly. The cost revelation mechanism inherent in the bidding process makes auctions a powerful means by which to reduce the problems of information asymmetry. Strategic bidding behavior, which may adversely affect the performance of sequential auctions, is difficult to address by means of auction design.

An emerging goal of ecosystem management is to maintain ecosystems within their range of natural variability, which requires attention to pre-EuroAmerican landscape-scale processes and corresponding landscape structures (e.g., old-growth forest distribution). The prevailing \"equilibrium\" view of ponderosa pine forest landscapes, for example, holds that frequent, low-intensity surface fires maintained open, park-like forests of large, old trees. Yet a contrasting \"nonequilibrium\" view suggests that some forest ecosystems are subject to unpredictable catastrophic disturbances that dramatically alter these ecosystems. To assess these views' relevance, we examined early historical accounts and records of natural disturbances in the ponderosa pine forests of the Black Hills in South Dakota and Wyoming (U.S.A.). There is evidence of frequent, low-intensity surface fires and large, catastrophic disturbances before EuroAmerican influence. Several large, stand-replacing fires occurred between 1730 and 1852, and, shortly after EuroAmerican settlement, a major outbreak of mountain pine beetles (Dendroctonus ponderosae Hopk.) occurred. The location of these severe disturbances coincides geographically with early explorers' reports of extensive tracts of relatively dense closed-canopy forests, including some very large patches (5000 + ha) of dense old growth. This contrasts with sparse, open-canopy forests thought to be maintained by periodic, low-intensity surface fires. We suggest that the cooler, moister, central and northern Black Hills and topographically protected areas may have been dominated by infrequent, catastrophic disturbances that maintained large patches of dense forests, including large, contiguous patches of old growth, in a relative state of nonequilibrium. The warmer and drier southern Black Hills, south-facing slopes, and exposed areas may have been dominated by frequent, low-intensity surface fires and other small disturbances that maintained open-canopy forests in a relative state of equilibrium. Proposed Black Hills National Forest management plans that exclusively endorse the equilibrium view are misdirected and will move the forest ecosystem farther outside its range of natural variability.

Use of suboptimal targeting tools to acquire environmental benefits is more the norm than the exception. We analyze how the joint spatial distribution of costs and environmental benefits affect efficiency losses from following targeting rules based on cost or benefits, rather than based on the benefit to cost ratio. Using analytical and numerical models, we demonstrate that the relative variability of costs and benefits and the correlation between the two are primary determinants of efficiency losses. We apply our framework to renewal of Conservation Reserve Program contracts and estimate how well alternative targeting tools obtain environmental benefits under reduced budgets.

To date, there have been few systematic assessments of the role of social institutions-rules, norms, and systems of authority and power-in creating and reconfiguring natural environments. In the desert grass and shrub lands of Rajasthan, India, where multiple, contending institutions govern village resources in a state of legal pluralism, the need for such research is pressing. Here, state political interventions vie against traditional common and semiprivate rule arrangements for control of valuable pasture and forest resources. This paper introduces an authority-centered theoretical vocabulary for such an analysis and reviews research conducted during 1993-1994 comparing four institutional forms to assess the role of institutions in configuring resource extraction decisions made by producers and in creating distinct and distinguishable biotic conditions. The study results demonstrate that responses to authority differ along axes of gender, caste, and class and so lead to varied decisions by producers. Each institutional form gives rise to a statistically significant pattern of annual and perennial herb distribution and of tree species occurrence. The location of enforcement, whether central or local, is shown to be less important than the breadth of authority forms controlling the resource. The results hold implications for future work in cultural/political ecology and for global change research. They also call into question any a priori assumptions of the superiority of either state of local resource management regimes.

Land managers need new tools, such as spatial models, to aid them in their decision-making processes because managing for biodiversity, water quality, or natural disturbance is challenging, and landscapes are complex and dynamic. Spatially explicit population models are helpful to managers because these models consider both species-habitat relationships and the arrangement of habitats in space and time. The visualizations that typically accompany spatially explicit models also permit managers to @'see@' the effects of alternative management strategies on populations of interest. However, the expense entailed in developing the data bases required for spatially explicit models may limit widespread implementation. In addition, many of the models are developed for one or a few species, and dealing with multiple species in a landscape remains a significant challenge. To be most useful to land managers, spatially explicit population models should be user friendly, easily portable, operate on spatial and temporal scales appropriate to management decisions, and use input and output variables that can be measured affordably.

During the 20th century, environmental problems have increased from sewage discharge in the first decennia towards climate change today. An increase in scale of threats implies an increase in scale of management and assessment. Successively, physico-chemical, biological and ecological assessment evolved but failed to stop deterioration. The development in techniques runs parallel to the evolution in assessment. Eight major groups of assessment techniques are distinguished: indices (saprobic, diversity, biotic), multimetrics and rapid techniques, physico-ecological, catchment scale, ecosystem components, assemblage/community, process, and non-taxonomic assessment. An increasing refinement is observed in objectives, measures and complexity, and a decreasing one in levels of scale, stream type and, more often, taxonomy. The applied algorithms were typically restricted to single summary measures. Multivariate analysis was introduced only recently. Assessment can do without a reference condition. Still, this condition is often used in assessment. Therefore, the role of the reference is discussed and it is concluded that, if used, it needs to be defined strictly. The role of nine concepts of lotic ecology in assessment is studied. Two major groups of concepts are distinguished. One is related to catchment-scale functioning of streams and the other to instream habitat-related processes and biodiversity. The 5-S-Model, a frame that divides the stream ecosystem into five major components: system conditions, stream hydrology, structures, substances and species (Verdonschot et al., 1998: The 5-S-Model, an integrated approach for stream rehabilitation. In H.O. Hansen & B.L. Madsen, River Restoration '96, Session lectures proceedings. National Environmental Research Institute, Denmark, International Conference arranged by the European Centre for River Restoration: 36-44), is a first attempt to comprise this knowledge in management. Finally, integrated ecological assessment is defined. It is based on three major approaches: an ecological typology approach, an ecological catchment approach and a societal approach. Ecological typology implies a nested multiple parameter approach based on regional ecological stream typology where types are scaled and different taxonomic groups are incorporated. Ecological typology sets the ecological demands necessary to make management sustainable. The ecological catchment approach implies a nested multiple scale approach which couples natural and anthropogenic features and dynamics of the catchment both in space and time. This approach sets the conditions within the catchment to facilitate sustainable catchment management. The societal approach adds human activities to the first two. It couples ecological demands and anthropogenic uses and supports those user choices that make management sustainable. The application of these three approaches is initiated to enable sustainable catchment management.[PUBLICATION ABSTRACT]