Andrzej Kędziora

Energy control of matter fluxes through land-water ecotones in an agricultural landscape

Ecotones play and important role in control of matter input into water bodies. The impacts of shelterbelt and meadow ecotones on ground water passage from cultivated fields to pond were studied. The reduction of water flux due to evapotranspiration by shelterbelts and meadows on slopes of different steepness were estimated. The horizontal passage of heat energy between cultivated fields and ecotones, which enhances evaporation in shelterbelts and meadows was demonstrated. The reduction of ground water flux by a ten meter wide shelterbelt or meadow surrounding a pond can reach as much as 100 per cent when the slope is about 1 degree, during a sunny day. Shelterbelts are a more effective measure for control of cycling matter than meadows. The greater the slope of the water table and the more intensive the radiation and advective processes, the more distinct the differences between shelterbelt and meadow impacts on groundwater flow are.

The influence of plant cover structures on water fluxes in agricultural landscapes

Water shortages, as well as floods and problems of water quality, especially its pollution by nitrates, have become worldwide threats to the sustainable development of human populations. In many regions of the world, water abstractions exceed available supplies (WMO, 1997). There is a prevailing premise that the best way to manage water resources is via large-scale technical interventions, such as new dams, aqueducts, pipelines, reservoirs and other devices for water withdrawals, storage, distribution or diversion (Gleick, 2003). Demand for water grew at more than twice the rate of global population growth in the 20th century, leading to many regional water crises (about 80 countries, constituting 40% of the world’s population, showed serious water shortages) and to a situation in which people presently use about half of the world’s available fresh water (WMO, 1997). It is no surprise then that water lies at the heart of many national and international conflicts globally. In an effort to address these problems, the UN Millennium Development Goals calls for a halving of the number of people without access to safe drinking water by 2015. It also calls for the implementation of strategies for sustainable water exploitation. The limited success so far of this initiative has compelled administrations to look for alternative water policies. Besides large water management constructions, so-called ‘soft-path solutions’ are proposed, which require much lower funding inputs and rely on decentralized decision making and use of more efficient technologies (Gleick, 2003). Stress is placed on the efficiency of water use for sanitation, food production, irrigation and other activities in small enterprises. In order to develop a strategy for sustainable water management, one has to grasp the system of relationships between the climatic constraints on water balance and the patterns of main water fluxes in landscapes, including the kinetics of water cycling and recycling and its uptake for human populations. Relying only on a single characteristic of a water regime often leads to incorrect conclusions. Thus, for example, the average annual precipitation in Finland amounts to about 550 mm and in Poland to 700 mm, but Poland is a more waterstressed country than Finland because evapotranspiration here is much higher than in Finland. Thus, the amount of precipitated water alone has little informative value for an evaluation of water conditions. Besides alreadyknown technical solutions for water storage and recycling, new options have been provided by the recent advances in landscape ecology (Ryszkowski and Kedziora, 1987; Olejnik and Kedziora, 1991; Ryszkowski et al., 1999; Kedziora and Olejnik, 2002).

Impact of Land-Use and Climate on Biodiversity in an Agricultural Landscape

The term “biodiversity” was used for the first time by wildlife scientist and conservationist [1] in a lay book advocating nature conservation. The term was not adopted by more then decade. In 1980 use of the term by Thomas Lovejoy in the Foreword to the book “Conservation Biology” [2] credited with launching the field of conservation biology introduced the term to the scientific community. There are many definitions of biodiversity. One of them, formulated in Millennium Ecosystem Assessment [3] reads: ” Biodiversity is the variability among living organisms from all sources, including terrestrial, marine, and other aquatic ecosystems and the ecological complexes of which they are part; this includes diversity within species, between species, and of ecosystems”. Biodiversity forms the foundation of the vast array of ecosystem services that critically contribute to human well-being. Biodiversity is important in human-managed as well as natural ecosystems. Decisions humans make that influence biodiversity affect the well-being of themselves and others [3].

Possibilities for the Development of Mixed Crop-Beef Farming in the Kościan Region Based on Natural Fodder Resources. Results from the MEA-Scope Case Study in Poland

Ongoing dominance of cereals in cropping patterns in the Kościan region of Poland creates threats to sustainable development because it may induce ecological problems. To reduce environmental pressure caused by simplified agricultural land use and to improve the management of grasslands, the possibility of developing mixed crop-beef farming as an alternative to arable farming is considered. Scenario models were developed for different farming types. The analysis focused on a comparison of economic performance, nitrogen balance and the evolution of soil carbon (C) stock between different models. The general conclusion was that beef-based scenarios for mixed farming were economically viable. They allowed for diversification of farm activities and supported the improvement of environmental performance in terms of better cropping patterns and soil C sequestration. However, an undesirable effect involved is a higher nitrogen (N) emission into the atmosphere due to N losses from manure before its application to a field.

Studies on Agricultural Landscape Management in Western Poland Plain

Increasing production farmers subsidise energy in order to simplify plant cover structure both within cultivated fields (selection of genetically uniform cultivates and elimination of weeds) and within agricultural landscape (elimination of hedges, stretches of meadows and wetlands, small mid-field ponds). Animal communities are also impoverished in cultivated fields. Fanners interfere with the matter cycling in agroecosystems directly by inputs of fertilisers, pesticides, etc., or indirectly by changing water cycling and decreasing holding capacities of soils for chemical compounds. In addition agricultural activity often leads to decrease of humus contents. Powerful machines used in modern tillage technologies not only strongly affect upon soil properties but also enable land surface levelling, modification of water drainage systems etc., which leads to changes in geomorphological characteristics of the terrain. All these effects of farming activity result in the development of a less complex network of interrelations among the components of agroecosystems. As a consequence of this simplification, relationships among agroecosystem components are altered, so that there is less tie-up in local cycles of matter. Thus increased leaching, blowing off, volatilisation and escape of various chemical compounds and materials from agroecosystems should be expected (Ryszxowski 1992, 1994, Ryszkowski et al. 1996).

Impact of climatic change on eco-hydrology: a case study for Poland

The impact of climatic change on variables of concern to eco-hydrology was examined. Long time series of records of temperature, precipitation and river flow for Poznan were analyzed and forecasts of tendencies were made. Spatial distribution of runoff and of the ratio of evapotranspiration to precipitation was obtained for the country. It was found likely that the dynamics of the hydrological cycle will accelerate. Annual precipitation, runoff and evapotranspiration will increase. The joint effect, including estimated growth in water demand, is likely to be a decrease in the amount of soil moisture.