1. Given the widespread impacts on habitats in the UK it is essential to understand how
habitat management measures could mitigate N deposition impacts and promote
recovery. This project reviews the effectiveness of ‘on-site’ land management methods
to mitigate nitrogen deposition impacts on sensitive habitats; assesses what effect current
management practice has on habitat response to nitrogen deposition; considers how
measures may be affected by climate change; and recommends realistic and practical
management measures for different habitat types which could be used to mitigate
nitrogen impacts or speed recovery.
2. The potential for management to mitigate N deposition impacts was considered across the
following broad habitats: broadleaved, mixed and yew woodland & (natural) coniferous
woodland; neutral grassland; calcareous grassland; acid grassland; dwarf shrub heath;
bog; coastal dunes and slacks; other coastal habitats. For all habitats we were able to
identify management techniques with some potential to mitigate N deposition impacts.
3. Management techniques may improve habitat suitability (e.g. control dominant species),
remove nitrogen from the system, or both.
4. However, all management techniques also have unintended consequences meaning that
their implementation might conflict with other conservation priorities.
5. There are a range of schemes and handbooks providing habitat management advice in the
UK. The following techniques were reviewed in detail: grazing; cutting; burning;
fertilisation; liming; hydrological management; scrub and tree management; disturbance.
6. Current management may already be partially offsetting the impact of N deposition.
7. Management for N is unlikely to make habitats more vulnerable to climate change. There
is complementarity in the management options required to tackle N deposition and
climate change. The frequency or intensity of measures such as grazing, cutting or
burning will all need to increase. Regional variation in climate change may lead to
different emphasis of management options in the wetter north west and the drier south
east.
8. Climate change will alter habitat sensitivity to N deposition, via changes in ecosystem
processes. Overall, climate change will make woodlands less sensitive to N deposition,
but will make heathlands more sensitive to N deposition. Effects on other habitats have
not yet been evaluated.
9. There is some potential for mitigating the impacts of N deposition through on-site
management although this varies greatly between habitat and management practice. It is
likely that small changes in management and adherence to appropriate guidelines could
partially improve habitat suitability and/or increase N removal.
10. The majority of management practices do not remove significant quantities of N (with the
exception of removing biomass or topsoil). Furthermore, management of a suitable
intensity to remove sufficient N to fully offset N added by atmospheric deposition is
likely to damage the habitat and result in a number of unintended consequences.
11. Further research is needed to determine the impacts of individual management practices
on the N budget in different habitats. Further research is also needed to explore the
potential for novel management techniques to remove N from sites.
12. For an individual site where N is identified as a pressure, a manager can look at current
management and compare this with the management recommendations in the report to
make changes where appropriate.
13. All management recommendations that remove N from the site move it elsewhere and
have the potential for unintended consequences. Consequently there is no substitute for
reducing the amount of N deposited onto a site which can only be achieved through
emission controls.
Atmospheric nitrogen (N) deposition is a recognized threat to plant diversity in temperate and northern parts of Europe and North America. This paper assesses evidence from field experiments for N deposition effects and thresholds for terrestrial plant diversity protection across a latitudinal range of main categories of ecosystems, from arctic and boreal systems to tropical forests. Current thinking on the mechanisms of N deposition effects on plant diversity, the global distribution of G200 ecoregions, and current and future (2030) estimates of atmospheric N-deposition rates are then used to identify the risks to plant diversity in all major ecosystem types now and in the future. This synthesis paper clearly shows that N accumulation is the main driver of changes to species composition across the whole range of different ecosystem types by driving the competitive interactions that lead to composition change and/or making conditions unfavorable for some species. Other effects such as direct toxicity of nitrogen gases and aerosols, long-term negative effects of increased ammonium and ammonia availability, soil-mediated effects of acidification, and secondary stress and disturbance are more ecosystem- and site-specific and often play a supporting role. N deposition effects in mediterranean ecosystems have now been identified, leading to a first estimate of an effect threshold. Importantly, ecosystems thought of as not N limited, such as tropical and subtropical systems, may be more vulnerable in the regeneration phase, in situations where heterogeneity in N availability is reduced by atmospheric N deposition, on sandy soils, or in montane areas. Critical loads are effect thresholds for N deposition, and the critical load concept has helped European governments make progress toward reducing N loads on sensitive ecosystems. More needs to be done in Europe and North America, especially for the more sensitive ecosystem types, including several ecosystems of high conservation importance. The results of this assessment show that the vulnerable regions outside Europe and North America which have not received enough attention are ecoregions in eastern and southern Asia (China, India), an important part of the mediterranean ecoregion (California, southern Europe), and in the coming decades several subtropical and tropical parts of Latin America and Africa. Reductions in plant diversity by increased atmospheric N deposition may be more widespread than first thought, and more targeted studies are required in low background areas, especially in the G200 ecoregions.
Site-occupancy models that predict habitat suitability for plant species in relation to measurable environmental factors can be useful for conservation planning. Such models can be derived from large-scale presence–absence datasets on the basis of environmental observations or, where only floristic data are available, using plant trait values averaged across a plot. However, the estimated modelled relationship between species presence and environmental variables depends on the type of statistical model adopted and hence can introduce additional uncertainty. Authors used an ensemble-modelling approach to constrain and quantify the uncertainty because of the choice of statistical model, applying generalised linear models (GLM), generalised additive models (GAM), and multivariate adaptive regression splines (MARS). Niche models were derived for over 1000 species of vascular plants, bryophytes and lichens, representing a large proportion of the British flora and many species occurring in continental Europe. Each model predicts habitat suitability for a species in response to climate variables and trait-based scores (evaluated excluding the species being modelled) for soil pH, fertility, wetness and canopy height. An R package containing the fitted models for each species is presented which allows the user to predict the habitat suitability of a given set of conditions for a particular species. Further functions within the package are included so that these habitat suitability scores can be plotted in relation to individual explanatory variables. A simple case study shows how the R package (MultiMOVE) can be used quickly and efficiently to answer questions of scientific interest, specifically whether climate change will counteract any benefits of sheep-grazing for a particular plant community. The package itself is freely available via http://doi.org/10.5285/94ae1a5a-2a28-4315-8d4b-35ae964fc3b9.
Businesses have an unrivalled ability to mobilize human, physical and financial capital, often manage large land holdings, and draw on resources and supply products that impact a wide array of ecosystems. Businesses therefore have the potential to make a substantial contribution to arresting declines in biodiversity and ecosystem services. To realize this potential, businesses require support from researchers in applied ecology to inform how they measure and manage their impacts on, and opportunities presented to them by, biodiversity and ecosystem services.We reviewed papers in leading applied ecology journals to assess the research contribution from existing collaborations involving businesses. We reviewed applications to, and grants funded by, the UK's Natural Environment Research Council for evidence of public investment in such collaborations. To scope opportunities for expanding collaborations with businesses, we conducted workshops with three sectors (mining and quarrying, insurance and manufacturing) in which participants identified exemplar ecological research questions of interest to their sector.Ten to fifteen per cent of primary research papers in Journal of Applied Ecology and Ecological Applications evidenced business involvement, mostly focusing on traditional rural industries (farming, fisheries and forestry). The review of UK research council funding found that 35% of applications mentioned business engagement, while only 1% of awarded grants met stricter criteria of direct business involvement.Some questions identified in the workshops aim to reduce costs from businesses' impacts on the environment and others to allow businesses to exploit new opportunities. Some questions are designed to inform long-term planning undertaken by businesses, but others would have more immediate commercial applications. Finally, some research questions are designed to streamline and make more effective those environmental policies that affect businesses.Business participants were forward-looking regarding ecological questions and research. For example, representatives from mining and quarrying companies emphasized the need to move beyond biodiversity to consider how ecosystems function, while those from the insurance sector stressed the importance of ecology researchers entering into new types of interdisciplinary collaboration.Synthesis and applications. Businesses from a variety of sectors demonstrated a clear interest in managing their impacts on, and exploiting opportunities created by, ecosystem services and biodiversity. To achieve this, businesses are asking diverse ecological research questions, but publications in leading applied ecology journals and research council funding reveal limited evidence of direct engagement with businesses. This represents a missed opportunity for ecological research findings to see more widespread application.
Abstract Soil biota accounts for ~25% of global biodiversity and is vital to nutrient cycling and primary production. There is growing momentum to study total belowground biodiversity across large ecological scales to understand how habitat and soil properties shape belowground communities. Microbial and animal components of belowground communities follow divergent responses to soil properties and land use intensification; however, it is unclear whether this extends across heterogeneous ecosystems. Here, a national-scale metabarcoding analysis of 436 locations across 7 different temperate ecosystems shows that belowground animal and microbial (bacteria, archaea, fungi, and protists) richness follow divergent trends, whereas β-diversity does not. Animal richness is governed by intensive land use and unaffected by soil properties, while microbial richness was driven by environmental properties across land uses. Our findings demonstrate that established divergent patterns of belowground microbial and animal diversity are consistent across heterogeneous land uses and are detectable using a standardised metabarcoding approach.
<p>Soil porosity controls the flow of mass and energy through soil, and thus plays a fundamental role in regulating hydrological and biochemical cycling at the land surface. Global land surface and earth system models commonly derive porosity from soil texture using pedotransfer functions. This does not allow for response to change in environment or management, or potentially important climate feedbacks. Furthermore, the approach does not fully represent the baseline spatial variation in this important soil property. Here we show that porosity, and bulk density (BD), depend on SOM in temperate soils, using two comprehensive national data sets, covering the full range of soil organic matter (SOM) (n=1385 & n=2570). Our novel use of analytical models with machine learning (ML) algorithms opens up new physical insight into controls on porosity and BD, while generalized additive mixed models (GAMMs) provide further insights and opportunities for prediction. Our models allow us to consider influence of management on soil compaction and recent observations that soil porosity responds to climate change. The dependence of soil porosity on SOM, more so than texture, indicates the need for a paradigm shift in the conceptualization and modelling of these soil physical properties. Broad habitat was also an important control, and explained some of the variance in the relationship between SOM and porosity. This highlights that changes in soil porosity may occur due to land use or climate change, and will create feedbacks to hydrological and biogeochemical cycling which should be represented in Global land surface models. This will also be important for other pedotransfer functions, e.g. the use of BD to determine carbon stock from concentration. &#160;In addition, we found opportunities for improved representation of the spatial pattern of porosity, even in the absence of measured data on SOM, based on climate and earth observation data.</p>
Summary Understanding and quantifying constraints to multiple ecosystem service delivery and biodiversity is vital for developing management strategies for current and future human well‐being. A particular challenge is to reconcile demand for increased food production with provision of other ecosystem services and biodiversity. Using a spatially extensive data base (covering Great Britain) of co‐located biophysical measurements (collected in the Countryside Survey), we explore the relationships between ecosystem service indicators and biodiversity across a temperate ecosystem productivity gradient. Each service indicator has an individual response curve demonstrating that simultaneous analysis of multiple ecosystem services is essential for optimal service management. The shape of the response curve can be used to indicate whether ‘land sharing’ (provision of multiple services from the same land parcel) or ‘land sparing’ (single service prioritization) is the most appropriate option. Soil carbon storage and above‐ground net primary production indicators were found to define opposing ends of a primary gradient in service provision. Biodiversity and water quality indicators were highest at intermediate levels of both factors, consistent with a unimodal relationship along a productivity gradient. Positive relationships occurred between multiple components of biodiversity, measured as taxon richness of all plants, bee and butterfly nectar plants, soil invertebrates and freshwater macroinvertebrates, indicating potential for management measures directed at one aspect of biodiversity to deliver wider ecosystem biodiversity. We demonstrate that in temperate, human‐dominated landscapes, ecosystem services are highly constrained by a fundamental productivity gradient. There are immediate trade‐offs between productivity and soil carbon storage but potential synergies with services with different shaped relationships to production. Synthesis and applications . Using techniques such as response curves to analyse multiple service interactions can inform the development of Spatial Decision Support tools and landscape‐scale ecosystem service management options. At intermediate productivity, ‘land‐sharing’ would optimize multiple services, however, to deliver significant soil carbon storage ‘land‐sparing’ is required, that is, resources focused in low productivity areas with high carbon to maximize investment return. This study emphasizes that targets for services per unit area need to be set within the context of the national gradients reported here to ensure best use of limited resources.
'%3e%3cpath fill='%23012169' d='M0 0v30h60V0z'/%3e%3cpath stroke='%23fff' stroke-width='6' d='m0 0 60 30m0-30L0 30'/%3e%3cpath stroke='%23C8102E' stroke-width='4' d='m0 0 60 30m0-30L0 30' clip-path='url(%23b)'/%3e%3cpath stroke='%23fff' stroke-width='10' d='M30 0v30M0 15h60'/%3e%3cpath stroke='%23C8102E' stroke-width='6' d='M30 0v30M0 15h60'/%3e%3c/g%3e%3c/svg%3e)
