Distribution and growth dynamics of invasive goldenrod (Solidago canadensis) in its introduced range in Estonia, and some Australian comparisons

Understanding the distribution and population dynamics of invasive plant species is fundamental to our capacity to appropriately predict and manage plant invasions. The invasion biology of non-native Solidago canadensis in Estonia was investigated for the first time by assessing its distribution patterns and growth dynamics. First, fifty-two peri-urban populations were surveyed, and population location, size, adjacent communities, number of shoots as well as shoot height were recorded. Then, thirty genets were excavated from previously surveyed populations in order to analyze their age and growth traits in the vicinity of Tartu. The majority of S. canadensis populations were small, i.e. occupying less than 50 m2, had 1 to 50 plants per population and were located predominantly on disturbed roadsides. The surveyed populations were young, with the average age of genets estimated to be five years at the time of sampling in 2006. We suggest that S. canadensis is well adapted to a wide range of habitats but predominantly occurs in human-disturbed habitats adjacent to settlements and roads. We found that Solidago canadensis genet age did not affect significantly its growth traits suggesting that growth traits are similar between younger and older genets

Global dataset of soil organic carbon in tidal marshes.

Tidal marshes store large amounts of organic carbon in their soils. Field data quantifying soil organic carbon (SOC) stocks provide an important resource for researchers, natural resource managers, and policy-makers working towards the protection, restoration, and valuation of these ecosystems. We collated a global dataset of tidal marsh soil organic carbon (MarSOC) from 99 studies that includes location, soil depth, site name, dry bulk density, SOC, and/or soil organic matter (SOM). The MarSOC dataset includes 17,454 data points from 2,329 unique locations, and 29 countries. We generated a general transfer function for the conversion of SOM to SOC. Using this data we estimated a median (± median absolute deviation) value of 79.2 ± 38.1 Mg SOC ha-1 in the top 30 cm and 231 ± 134 Mg SOC ha-1 in the top 1 m of tidal marsh soils globally. This data can serve as a basis for future work, and may contribute to incorporation of tidal marsh ecosystems into climate change mitigation and adaptation strategies and policies

Global dataset of soil organic carbon in tidal marshes

Tidal marshes store large amounts of organic carbon in their soils. Field data quantifying soil organic carbon (SOC) stocks provide an important resource for researchers, natural resource managers, and policy-makers working towards the protection, restoration, and valuation of these ecosystems. We collated a global dataset of tidal marsh soil organic carbon (MarSOC) from 99 studies that includes location, soil depth, site name, dry bulk density, SOC, and/or soil organic matter (SOM). The MarSOC dataset includes 17,454 data points from 2,329 unique locations, and 29 countries. We generated a general transfer function for the conversion of SOM to SOC. Using this data we estimated a median (± median absolute deviation) value of 79.2 ± 38.1 Mg SOC ha−1 in the top 30 cm and 231 ± 134 Mg SOC ha−1 in the top 1 m of tidal marsh soils globally. This data can serve as a basis for future work, and may contribute to incorporation of tidal marsh ecosystems into climate change mitigation and adaptation strategies and policies

Wooded meadows of Estonia: conservation efforts for agricultural landscape

We provide an overview of the amount and ecological condition of wooded meadows throughout Estonia after significant changes in agriculture in the second part of 20th century. We also present the first attempt to estimate the success of recent conservation efforts for wooded meadows. Our analysis is based on recent exhaustive inventories. We found that Estonia, despite a decrease of the area in wooded meadows by two orders of magnitude during the 20th century, still has about 8400 ha remaining of which approximately 5800 ha are meadows with, at the least, an intermediate conservation value. The latter is directly dependent on mowing regime. Efforts to preserve wooded meadows include establishment of protected areas and financial support for mowing. The national conservation subsidy has been useful and supportive for wooded meadows, however the total amount of this subsidy has been small compared to the area that could be supported. The much larger funds of agri-environmental subsidies have largely not been available for wooded meadows. Moreover, there has been no record keeping about subsidisation of semi-natural grasslands using agricultural support schemes. Although the preservation of some good examples of wooded meadows in Estonia seems guaranteed, further degradation of this valuable habitat type on a national scale is very probable.

Post Hoc Assessment of Stand Structure Across European Wood-Pastures: Implications for Land Use Policy

Europe's woodland and savanna rangelands, often part of silvopastoral systems known as wood-pastures, are deteriorating because of abandonment that leads to return to a forested state or lack of tree regeneration from overgrazing or tree and shrub removal. Despite numerous local studies, there has been no broader survey of the stand structure of European wood-pastures showing which systems are at risk of losing their semiopen character. This overview aims to 1) show some of the differences and similarities in wood-pastures from landscapes across Europe and 2) identify which of these wood-pastures are at risk of losing their semiopen character. We collated a dataset of 13 693 trees from 390 plots in wood-pastures from eight different European regions (western Estonia, eastern Greece, northern Germany, Hungary, northern Italy, southern Portugal, central Romania, and southern Sweden), including tree diameters at breast height, tree density, management type, and tree species composition. On the basis of their structural characteristics, we classified wood-pastures using principal component analysis (PCA) and cluster analysis. The PCA showed a gradient from dense wood-pastures with high levels of regeneration (e.g., in Estonia) to sparse wood-pastures with large trees but a lack of regeneration (e.g., in Romania). Along this gradient, we identified three main groups of wood-pastures: 1) sparse wood-pastures with mostly big trees; 2) dense wood-pastures composed of small trees, and 3) wood-pastures containing a wide range of tree ages. Our results show a large structural gradient in European wood-pastures, as well as regeneration problems varying in their severity, highlighting the importance of social-ecological context for wood-pasture conditions. To maintain the ecological and cultural integrity of European wood-pastures, we suggest 1) more comprehensively considering them in European policies such as the Common Agricultural Policy and EU Habitats Directive, while 2) taking into account their structural characteristics and social-ecological backgrounds.The Rangeland Ecology & Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information