JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org. SUMMARY(1) An experimental comparison of the effects of eleven cutting treatments on roadside vegetation was made at two sites in Cambridgeshire over a period of 18 years. The treatments were combinations of cutting date, cutting frequency (0, 1, 2, or 5 times per annum) cutting machine (haymower, flail mower or rotary mower) and leaving or removing cuttings.(2) Vascular plant species-richness of the vegetation was unaffected by altering the date of a single cut from June to July or by cutting with different types of machine. It was lowest in the uncut plots and highest in plots cut twice per annum.(3) Increased cutting frequency significantly decreased the frequency of ten mainly coarse growing species, including Elymus repens, Arrhenatherum elatius and Anthriscus sylvestris. Eleven finer species (mostly grasses) increased in frequency and two others (Ranunculus repens and Plantago lanceolata) reached a maximum at two cuts per annum.(4) Removing cuttings led to an increase in plant species-richness, mainly due to an increase in herbs. Removing cuttings led to a decrease in extractable potassium in the soil but most other soil nutrients, including total and available nitrogen, were unaffected. It is suggested that the increase in species-richness was not due to reduced levels of soil nutrients, but was probably associated with the disturbance and scarification which accompanied the removal of cuttings by hand raking, and with the alleviation of the smothering effect caused by leaving cut vegetation on the verges.(5) The effects of the treatments on species-richness and the frequencies of individual species were very similar at both sites.

No abstract

ABSTRACT. The International Long-Term Ecological Research (ILTER) network comprises > 600 scientific groups conducting sitebased research within 40 countries. Its mission includes improving the understanding of global ecosystems and informs solutions to current and future environmental problems at the global scales. The ILTER network covers a wide range of social-ecological conditions and is aligned with the Programme on Ecosystem Change and Society (PECS) goals and approach. Our aim is to examine and develop the conceptual basis for proposed collaboration between ILTER and PECS. We describe how a coordinated effort of several contrasting LTER site-based research groups contributes to the understanding of how policies and technologies drive either toward or away from the sustainable delivery of ecosystem services. This effort is based on three tenets: transdisciplinary research; cross-scale interactions and subsequent dynamics; and an ecological stewardship orientation. The overarching goal is to design management practices taking into account trade-offs between using and conserving ecosystems toward more sustainable solutions. To that end, we propose a conceptual approach linking ecosystem integrity, ecosystem services, and stakeholder well-being, and as a way to analyze trade-offs among ecosystem services inherent in diverse management options. We also outline our methodological approach that includes: (i) monitoring and synthesis activities following spatial and temporal trends and changes on each site and by documenting cross-scale interactions; (ii) developing analytical tools for integration; (iii) promoting trans-site comparison; and (iv) developing conceptual tools to design adequate policies and management interventions to deal with trade-offs. Finally, we highlight the heterogeneity in the socialecological setting encountered in a subset of 15 ILTER sites. These study cases are diverse enough to provide a broad cross-section of contrasting ecosystems with different policy and management drivers of ecosystem conversion; distinct trends of biodiversity change; different stakeholders' preferences for ecosystem services; and diverse components of well-being issues.

Long-term integrated monitoring is an important approach for investigating, detecting and predicing the effects of environmental changes. Currently. European freshwaters, glaciers, forests and other natural and semi-natural ecosystems and habitats are monitored by a number of networks established by different organisations. However, many monitoring programmes have a narrow focus (e.g. targeting individual ecosystems) and most have different measurement protocols and sampling design. This has resulted in poor integration of ecosystem monitoring at a European level, leading to some overlapping of efforts and a lack of harmonised data to inform policy decisions. The need for a consistent pan-European long-term integrated monitoring of terrestrial systems programme is recognised in the scientific community. However, the design of such a system can be problematic, not least because of the constraints imposed by the need to make maximum use of existing sites and networks. Based on the outcomes of the NoLIMITS project (Networking of Long-term Integrated Monitoring in Terrestrial Systems). this article reviews issues that should be addressed in designing a programme based on existing monitoring sites and networks. Four major design issues are considered: (i) users' requirements, (ii) the need to address multiple objectives, (iii) role of existing sites and (iv) operational aspects.