and use and management measures have strong implications on environmental properties such as the quality of soil, water and air, and biodiversity, as well as on social and cultural values. This is also clearly indicated in the Swedish National Environmental Quality Goals where measures to meet quality criteria have been set. However, there are several question marks concerning relations between land management and environment, and in particular there are conflict situations where a specific management form might be positive for the environment in one respect, but negative in another. Although it is not the mandate of science to balance different needs, it is definitely its role to describe the environmental, social and cultural impacts, as well as the economic viability, including the use of environmental and sustainability assessment tools. In this way science enables decisions towards sustainable land use.The environmental, social and cultural impacts from land use might in the future be even bigger as the needs for food, feed, fibre and fuel are supposed to increase substantially. At the same time climate change and loss of natural resources will further limit our ability to meet the demands for food, feed, fibre and fuel. In short, we need to produce more under more difficult circumstances, with less available resources and with less (preferably not any) environmental negative impact. Thus, there is an urgent need to more accurately understand relations between environment and a number of land management measures. Towards this background, the aim of this project was to describe the state of art concerning land management and environment and to elucidate urgent knowledge gaps in order to enable prioritization of further research. The focus is on Swedish conditions, although globalization due to increased global trading and increased global environmental concerns necessitate a certain outlook beyond national boundaries.There is almost an unlimited amount of land use and management varieties. For this reason the study was restricted to some management forms that either concerns a large part of Sweden or, according to the present knowledge, may provide big consequences and/or big uncertainties. It was also restricted to terrestrial land use including wetlands, i.e. the use of water bodies, and fisheries are excluded. Included are complicated questions in forestry such as harvest of biomass in production forestry (c. 60% of all Swedish land), use of harvest residues, cutting forms, nitrogen fertilization, liming, choice of tree species and drained peat-land management. In agriculture we focused on fertilization, liming, cropping systems and tillage and crop-residue management. We decided not to evaluate the use of genetically modified organisms neither in agriculture nor in forestry as the large political and environmental uncertainties involved motivate a report by itself. Finally we also assess methods and consequences for energy forestry and, briefly, for reindeer grazing since about 40% of the Swedish land-area is used for reindeer grazing. If reindeer production is used as an alternative for intensive meat production it will be a measure to decrease emissions of greenhouse gases. Grazing by reindeer affects biodiversity, often positively, especially in areas that suffer from increased abundance of broad-leaved vegetation due to climatic changes. Conflicts are possible in future: the area that is suitable for reindeer grazing may decrease due to a warmer climate, but also due to demands for agricultural development. The report is organized in such a way that the management forms are discussed one by one, followed by a systems perspectives approach. We begin with summarizing conclusions .Systems perspective – How to read figures in the reportFor most chapters in the report there are one or two summarizing figures drawn from an environmental systems perspective. For most options described in the figures there is a reference state given in the figure caption (although not illustrated in the figure). When so, the figure must be read with the reference state in mind as e.g. an increase or decrease in biodiversity depends on that reference state. In the figures, boxes represent activities, and arrows either represent flows, or simply “leads to”, when connecting two activity boxes. Green colour signifies avoided activities and related resource use and emissions. Grey colour signifies activities or flows that are likely to be of minor importance in the specific scenario. Oval shapes with dotted boundaries and open arrows at both ends represent activities which life cycles should be included in a systems perspectives for a full picture, but which are either beyond the scope of the report, or link to an earlier figure which is then given. In two figures life cycle data from the CPM (Center for environmental assessment of product and material systems) LCA database, 2011, is included. These date from 2005 and are included to give the reader an idea of the size of resource use and emissions involved.In the summaries below the pictures, the various effects, goal conflicts and the knowledge gaps discussed refer to environmental effects and ecosystem services. Conclusions on economic and social aspects are beyond the scope of this report.
Summary and discussionTable 1 is a very condensed summary of the report. It must be read with the comparisons made in mind, i.e. a specific action is not necessarily positive or negative with regard to the chosen parameters generally speaking – only as compared to the reference states used in this report. The effect on climate change is either direct (source or sink of carbon dioxide) or indirect (via a substitution effect). In the case of fossil fuel substitution there is a delay in climate change mitigation; whereas the emission of CO2 from biomass burning is immediate, the uptake of CO2 in the trees that are replacing the cut trees is taking place over decades. Generally speaking, substitution for a construction material is more effective than substitution for fuel. Notably, the table says nothing of the size of the impacts discussed; for this we refer to the special chapters and the literature cited. Neither does the table, nor the report, say anything about how to measure the impact of the different actions. Let alone the report says something about how the various effects can be compared to each other. Most plausible, the answers to these questions will vary from case to case, but also between different actors in the field, depending on what is ascribed the highest importance – or value – in different situations (Haider & Jax 2007). Critical trade-offsIt can be seen from table 1 that many activities that have a positive effect on climate change through a stock or sink mechanism also have positive effects on biodiversity, whereas an increased substitution effect tend to conflict with biodiversity. Similar patterns are there for eutrophication and water regulation (when relevant). These patterns give rise to complex choices as it has to be considered how important harvest of biomass (substitution effect) is as compared to e.g. biodiversity or eutrophication. Except local and case specific aspects – social as well as ecological – there is also a time aspect involved. Our obligations to future generations also needs to be taken into consideration in management of natural resources (de-Shalit 1995; Dobson 1999).Notably, biodiversity, the nitrogen cycle and climate change (in that order) have been pointed out by Rockström et al. (2009) as the three most critical out of nine so called planetary boundaries. Crossing these boundaries is, according to the authors, associated with a risk of deleterious, possibly disastrous consequences for humans. This is pointed out to underline how critical land use measures are, and that the trade-offs between climate change, biodiversity and nitrogen cycle impacts are far from obvious. How do we determine what degree of climate change that corresponds to a given change of biodiversity? It can be argued that increased climate change will in the end affect biodiversity negatively, but on the other hand it can also be argued that higher biodiversity generally means more resilient ecosystems, and more resilient ecosystems cope better with climate changes. A few of the land use measures investigated are positive from climate change point of view as well as from a number of other perspectives. These measures include forest reservation (in the short term), wetland restoration, livestock production with ley (if compared to livestock production with only arable crops), and energy forests (if compared to agriculture). A switch to deciduous tree species may also fall into this category, although here there’s a lack of knowledge regarding productivity as well as emissions associated with many tree species. Similarly, certain kinds of selective cutting may be positive from many points of view, but again there are uncertainties with regard to actual emissions. Such (potential) win-win solutions are usually only possible on small areas compared to the area subject to, e.g., conventional forestry, but may be highly significant for the preservation of threatened biodiversity and a number of other ecosystem functions. A national land use strategy aiming for (environmental) win-win options only will however not be possible. Tradeoffs between different environmental values will be necessary. Many of the parameters discussed through the report depend on site specific characteristics. Occurrence of species and site conditions such as soil properties, geology, hydrology, climate, deposition vary from one place to the other. In addition to this, people have different preferences, both at the individual level and at the cultural level. All of this, on top of the scientific difficulty of saying what is “best” when it comes to trade-offs between e.g. climate change and biodiversity, makes it impossible to recommend a “best land management option” on a general level; it will vary from one place to the other and over time, and a variety of options will be needed. A variety of options can be seen as a means of safeguarding a variety of values and ecosystem services, meeting different needs and preferences of people, and as a way of precautious risk spreading. The issue is further complicated when social and economic aspects, in terms of cultural ecosystem services are added. Briefly, cultural ecosystem services are “The non-material benefits people obtain from ecosystems through spiritual enrichment, cognitive development, reflection, recreation, and aesthetic experience, including, e.g., knowledge systems, social relations, and aesthetic values.” (Millennium Ecosystem Assessment 2003, p 58). As an example, productivity may be somewhat lower for selective cutting than for clear-cut forestry as well as for deciduous forests compared to spruce stands. On the other hand, selective cutting and deciduous forests may enable cultural, aesthetic and recreational values that production forestry misses. At the same time, it is more plausible that the selective cutting-forests and the deciduous forests enable cultural and recreational activities such as fishing, picking wild berries and hunting. In the case the economic value of these activities is limited (such as in many high-income countries), it is reasonable to include them in the cultural ecosystem services as they contribute to the high cultural, aesthetic, social and health values of a biodiverse landscape (Norling 2001). The cultural ecosystem services are most plausible difficult to replace (Lisberg Jensen 2008). In many cases, then, trade-offs seem to be unavoidable not only between environmental aspects, but also between environmental aspects on the one hand and social and economical aspects on the other, especially if including the global situation in the reasoning (Dobson 2007). In these tradeoffs, science can give advice, but the decisions remain political, and dependent of valuations and preferences. Concerning preferences, there is e.g. a risk that many preferences that people have, are monotonous, short sighted, temporary or just unrealistic to an extent that will challenge environmental decision making, environmental policy and/or environmental ethics (Minteer, Corley & Manning 2004; Minteer &Miller 2011). Furthermore, there is an extensive discussion in environmental ethics about the importance of natural landscapes (Callicott 2001; Hettinger 2002). On the other hand, empirical studies show that naturalness is not crucial. On the contrary, cultivated landscapes obviously have the social, cultural, aesthetic and spiritual values that many people appreciate (Norling 2001).