Seeds of change: The value of using Rhinanthus minor in grassland restoration

Question: What is the value of using Rhinanthus minor in grassland restoration and can restrictions on its establishment be overcome? Location: England (United Kingdom). Methods: Two experiments were established to determine the efficacy of inoculating R. minor on a suite of four agriculturally improved grasslands and the efficacy of using R. minor in grassland restoration. In Experiment 1, the effect of herbicide gap creation on the establishment and persistence of R. minor in grasslands ranging in productivity was investigated with respect to sward management. In Exp. 2, R. minor was sown at 1000 seeds/m² in conjunction with a standard meadow mix over a randomized plot design into Lolium perenne grassland of moderate productivity. The treatment of scarification was investigated as a treatment to promote R. minor. Results: Gap size had a significant role in the establishment and performance of R. minor, especially the 30 cm diameter gaps (Exp. 1). However, R. minor failed to establish long‐term persistent populations in all of the agriculturally improved grasslands. In Exp. 2, establishment of R. minor was increased by scarification and its presence was associated with a significant increase in Shannon diversity and the number of sown and unsown species. Values of grass above‐ground biomass were significantly lower in plots sown with R. minor, but values of total above‐ground biomass (including R. minor) and forb biomass (not including R. minor) were not affected. Conclusions: The value of introducing R. minor into species‐poor grassland to increase diversity has been demonstrated, but successful establishment was dependent on grassland type. The scope for using R. minor in grassland restoration schemes is therefore conditional, although establishment can be enhanced through disturbance such as sward scarification.     

The impact of Rhinanthus minor in newly established meadows on a productive site

Question: What is the impact of the presence of Rhinanthus minor on forb abundance in newly established swards? Location: Wetherby, West Yorkshire, UK (53°55’N, 1°22’W). Method: A standard meadow mix containing six forbs and six grasses was sown on an ex‐arable field and immediately over‐sown using a randomised plot design with three densities of Rhinanthus minor (0, 600, and 1000 seeds per m²). Above‐ground biomass was analysed over a period of three years, while detailed assessments of sward composition were performed during the first two years. Results: Values of grass biomass were reduced in the presence of Rhinanthus, especially at the higher sowing density. The ratio of grass: forb biomass was also lower in association with Rhinanthus, but only at the higher sowing density. The presence of Rhinanthus had no effect on species number or diversity, which decreased between years regardless of treatment. Conclusions: Although not tested in a multi‐site experiment, the benefit of introducing Rhinanthus into newly established swards to promote forb abundance was determined. The efficacy of Rhinanthus presence is likely to depend on whether species not susceptible to the effects of parasitism are present.     

Changes of species richness pattern in mountain grasslands: abandonment versus restoration

Changes in plant species richness at various spatial scales were investigated by manipulative experiment in mountain grasslands. The aim of the research was to compare changes in species richness in newly abandoned sites and sites where restoration measures were applied after 20 years of abandonment. The plots were located in two vegetation types with different moisture regime. Species richness decreased significantly after abandonment, mainly at the finest spatial scale of 10 × 10 cm. There was significant increase of species richness on restored sites, but it was apparent mainly at a larger scale. However, even 4 years of regular mowing were not sufficient to restore species richness to the level typical for traditionally managed grasslands in the region. No significant difference was found in the performance of the 2 contrasting vegetation types (wet and dry) in relation to management measures. A significant difference in scale-dependent species richness was only observed. The dry type had a steeper species-area curve, with a lower number of species at the finest spatial scale. According to the results of the experiment, mountain grasslands are very vulnerable habitats, losing their conservation value quickly after abandonment. Restoration is possible due to an extensive species pool in the region, but return to the original species richness at all spatial scales is quite a long process.     

Estimating economic values of vegetation restoration with choice experiments: a case study of an endangered species in Lake Kasumigaura, Japan

As the pace of ecosystem restoration increases, more attention has been directed towards understanding public preferences for ecosystem restoration projects. This paper utilizes a choice experiments technique to evaluate the restoration project of an endangered species, Nymphoides peltata (known locally as asaza) in Lake Kasumigaura, Japan. The restoration project evaluated in this paper consists of two attributes: an extinction risk and a lakeshore ecosystem. First, we observe a positive willingness-to-pay for the vegetation restoration project: the mean willingness-to-pay for restoring the endangered specie and avoiding extinction was about JPY6,800 and the mean willingness-to-pay for restoring the covering area to the ideal condition that the species originally inhabited in 1996 was about JPY1,600. Second, we clarify what kinds of individual characteristics affect preferences for restoration projects compared with preferences for the status quo. The results show that respondents who have strong environmental attitudes, visit experience, high income, and are female are more likely to prefer restoration projects to the status quo. Third, we investigate whether knowledge and comprehension of ecological information have any influence on respondents’ value formations. We find that respondents’ comprehension of ecological information is positively related to their willingness-to-pay for the avoidable level of extinction risk attribute, while respondents’ knowledge of ecological terms has no effect. Overall, our findings suggest that the public strongly desires the avoidance of extinction of endangered species, and indicates that researchers should be careful about how ecological information is given.

Predicting the establishment success of introduced target species in grassland restoration by functional traits

Species‐rich semi‐natural grasslands are highly endangered habitats in Central Europe and numerous restoration efforts have been made to compensate for the losses in the last decades. However, some plant species could become more easily established than others. The establishment success of 37 species was analyzed over 6 years at two study sites of a restoration project in Germany where hay transfer and sowing of threshing material in combination with additional sowing were applied. The effects of the restoration method applied, time since the restoration took place, traits related to germination, dispersal, and reproduction, and combinations of these traits on the establishment were analyzed. While the specific restoration method of how seeds were transferred played a subordinate role, the establishment success depended in particular on traits such as flower season or the lifeform. Species flowering in autumn, such as Pastinaca sativa and Serratula tinctoria, became established better than species flowering in other seasons, probably because they could complete their life cycle, resulting in increasingly stronger seed pressure with time. Geophytes, like Allium angulosum and Galium boreale, became established very poorly, but showed an increase with study duration. For various traits, we found significant trait by method and trait by year interactions, indicating that different traits promoted establishment under different conditions. Using a multi‐model approach, we tested whether traits acted in combination. For the first years and the last year, we found that models with three traits explained establishment success better than models with a single trait or two traits. While traits had only an additive effect on the establishment success in the first years, trait interactions became important thereafter. The most important trait was the season of flowering, which occurred in all best models from the third year onwards. Overall, our approach revealed the potential of functional trait analysis to predict success in restoration projects.     

Establishment of Picea abies seedlings in a central European mountain grassland: an experimental study

Abstract. Secondary meadows in the Kru?né hory mountains, central Europe, are not colonized by woody species, although they have been abandoned for half a century and are surrounded by Picea abies (Norway spruce) forests. The causes of inhibition of establishment of Norway spruce seedlings in the meadows were tested experimentally. The experiment was started in a masting year to ensure sufficient seed input. Four treatments (vegetation cut; vegetation cut and litter removed; all above-ground biomass and topsoil removed; control) were combined in a factorial design. The effect of browsing, mainly by deer, was assessed by fencing half of the experimental plots. Seedling establishment differed among treatments (all pair-wise differences were significant) but was independent of fencing. In contrast, seedling survival was influenced both by the treatment and fencing. At the end of the second year, only the plots with all biomass and organic topsoil removed supported viable populations of spruce seedlings. Dense herb cover and a thick layer of slowly decaying litter are considered the main factors inhibiting the establishment of woody species.     

World historical mapping and potential distribution of Cinchona spp. in Peru as a contribution for its restoration and conservation

Peru is a megadiverse country in neotropical flora and is home to an important genus of plants called Cinchona and commonly all its individual species are called Cinchona Tree (Cinchona spp.), which represents the national tree for this nation. This country has 18 species, a group of these species are listed as vulnerable, endangered, and their population trend is currently unknown. This genus is at risk of extinction due to overexploitation for its medicinal, constructive and food uses. The IUCN also mentions that increased species assessments and records will help make the IUCN Red List a “barometer of life”. Based on the fact that understanding the effects of environmental change on ecosystems requires the identification of historical and current baselines, which can act as reference conditions, this research generated georeferenced global historical maps of Cinchona spp. and then determined the appropriate sites based on environmental variables using the MaxEnt software and established the probabilities of occurrence of this genus in Peru to establish priority areas for its conservation and restoration. Four maps were obtained, one for each centennial, from 1737 to the present, with 10 860 occurrences of Cinchona. In the MaxEnt modeling, 10.30 % (13 3172.56 km²) and 19.20 % (24 7371.32 km²) of Peru's surface area had high ( > 0.6) and moderate (0.4–0.6) probabilities, respectively, of hosting Cinchona. Only 7.6 % (17 305.32 km²) and 22.0 % (50 153.73 km²) of the areas with high and moderate distribution potential, respectively, were covered by natural protected areas. Likewise, 11.90 % (21 738.75 km²) and 33.20 % (60 789.17 km²) of the high and moderate probability lands, respectively, correspond to degraded areas (DAs) and, therefore, are considered a priority for restoration with Cinchona spp. The results may stimulate the rethinking of decision making for the National Action Plan for Reforestation with Species of the Genus Cinchona and other plans or tools for Cinchona conservation in Peru.     

Ten lessons in 20 years: Insights from monitoring fauna and temperate woodland revegetation

In the last two decades, there has been enormous effort dedicated to better understanding how to restore and manage temperate native woodland vegetation in Australia's eastern wheat–sheep belt, and the consequences for fauna. This study presents ten of the most important lessons learned from the work to date by the Lindenmayer group at the Fenner School of Environment and Society at The Australian National University.     

Restoring Kangaroo Grass (Themeda triandra) to grassland and woodland understoreys: a review of establishment requirements and restoration exercises in south-east Australia

Summary Temperate grassy ecosystems are amongst Australia's most endangered ecosystems. Most remnants are small, fragmented and highly degraded. Practical methods for restoring native understorey species are urgently required. Dominant native grasses such as Kangaroo Grass (Themeda triandra Forssk.) and Tussock‐grasses (Poa species) have been eliminated from many remnants by heavy grazing in the past. The reintroduction of these grasses is a critical step for understorey restoration. This paper (i) reviews the literature on Themeda seed biology and seedling establishment; (ii) summarizes the lessons learnt from three major attempts to establish Themeda stands in south‐east Australia; and (iii) identifies the research needed to enhance Themeda restoration. Considerable information is available on Themeda seed and establishment biology, and restoration exercises have shown that Themeda stands can be readily established by surface‐spreading awned seeds in seed‐bearing hay. However, many practical challenges remain, including the need to identify optimal sowing periods, create better seedbed conditions, develop practical mulching techniques, and improve weed control. The use of seed‐bearing hay has constrained restoration to relatively small areas in the past. Future trials may benefit by using more concentrated seed products such as seed‐bearing florets and pure seeds which permit larger areas to be restored at one time.     

Effects of long‐term cutting in a grassland system: perspectives for restoration of plant communities on nutrient‐poor soils

Abstract. The upper courses of brook valley systems harbour Nardo‐Galion saxatilis communities characteristic of oligo‐trophic soils under low‐intensity farming. Most of these communities have disappeared under intensified farming i.e. application of fertilizers. We studied the possibilities of restoration i.e. re‐establishment of the former plant community by adopting various cutting regimes after the cessation of fertilization in 1972. The various cutting regimes revealed different effects after 25 yr. Regimes with cutting every second year with or without removal of the swath, and complete abandonment deviated from the other regimes that included annual haymaking with different frequency and timing. The latter group of cutting regimes came closer to the community of an adjacent field where fertilization stopped in 1967. This field in turn harboured several Nardo‐Galion species after 25 yr of annual cutting, and showed more resemblance with a local reference community (at a distance of 500 m) that had not been fertilized since the 1940s. The local reference still does not match poorly developed Nardo‐Galion saxatilis communities found in the region of ca. 50 km around the study area, and is far from well developed Nardo‐Galion communities in the same region. The study site still harbours several species characteristic of eutrophic soil and few species characteristic of oligotrophic soil after 25 yr of annual cutting and removal of the swath. The soil seed bank harbours only few target species. Although species characteristic of oligotrophic soil are present in an adjacent field and Nardo‐Galion saxatilis species occur at 500 m, they have not (yet) established in the target area.     

Remediation of ecosystems damaged by environmental contamination: Applications of ecological engineering and ecosystem restoration in Central and Eastern Europe

To investigate the applicability of ecological engineering to pollution problems prevalent in present-day Central and Eastern Europe, a SCOPE-UNEP sponsored workshop was held in Estonia in November 1995. The workshop was undertaken specifically to obtain information from and to train planners, managers and scientists in the region. These ‘countries in transition' face, in many respects, unique environmental problems as a result of their recent domination by a centralized planning government system. Twenty workshop findings that resulted from workshop presentations and subsequent discussion are presented. Six papers published as part of this special issue of Ecological Engineering, and summarized here, deal with the general principles of mineland restoration, acidification effects and mitigation in Poland, reestablishment of riparian buffer strips in Estonia, recovery of forests in the Black Triangle of Czechoslovakia and Poland, restoration after 10 years near the Chernobyl nuclear plant accident in the Ukraine, and studies on remediation of contaminated soils in Belarus.     

Reversing expansion of Calamagrostis epigejos in a grassland biodiversity hotspot: Hemiparasitic Rhinanthus major does a better job than increased mowing intensity

Questions

Can hemiparasitic Rhinanthus major originating from a local population suppress the competitive clonal grass Calamagrostis epigejos and reverse its expansion in species‐rich semi‐natural grasslands? Does sowing seeds of R. major facilitate restoration of target meadow vegetation? Is R. major more beneficial for biodiversity restoration/conservation than increased mowing intensity, a conventional measure to suppress C. epigejos?

Location

?ertoryje National Nature Reserve, Bílé Karpaty (White Carpathians) Protected Landscape Area, Czech Republic.

Methods

We conducted a before‐after‐control‐impact experiment in meadow patches heavily infested by C. epigejos: eight blocks, each containing four plots with four treatment combinations: (1) traditional management, i.e. mowing once in summer, (2) mowing in summer and autumn (3) mowing in summer and seed sowing of R. major, (4) mowing in summer and autumn and seed sowing of R. major. Above‐ground biomass of C. epigejos and vegetation composition of each of the plots were monitored every year from 2013 to 2016. To assess the effects of treatments, we analysed biomass production of C. epigejos, herb layer cover and vegetation composition.

Results

Both sowing R. major and an additional autumn meadow cut significantly suppressed C. epigejos. Their effects were additive and of comparable size. Both treatments also had significant but markedly different effects on community composition. Rhinanthus major facilitated directional community composition change towards the regional Brachypodio‐Molinetum meadows. In contrast, increased mowing intensity significantly decreased frequency of threatened species, which however may have also been influenced by R. major.

Conclusions

Sowing of autochthonous R. major seeds was demonstrated as an efficient tool to suppress C. epigejos and facilitate community restoration. It can be combined with an additional meadow cut to further accelerate decline of the grass. The additional cut should however be used as a short‐term practice (1–2 years) only to minimize potential negative effects of its long‐term application on some threatened plant species. The effects of R. major are comparable to those of Rhinanthus alectorolophus reported previously. As a species occurring naturally in species‐rich dry grasslands, R. major has a broader and longer‐term application potential than R. alectorolophus in ecological restoration and conservation of these communities.     

Ecosystem response to changes in water level of Lake Ontario marshes: lessons from the restoration of Cootes Paradise Marsh

A general understanding of how aquatic vegetation responds to water-level fluctuations is needed to guide restoration of Great Lakes coastal wetlands because inter-annual and seasonal variations often confound effects of costly remedial actions. In 1997, common carp (Cyprinus carpio) was removed from Cootes Paradise Marsh (L. Ontario) to reduce sediment resuspension and bioturbation, and thus regenerate marsh plants that had declined dramatically since the 1930s. Data from 1934 to 1993 were re-assembled from the literature to relate percentage cover of emergent vegetation to mean summer water level. A non-linear regression equation explained close to 90% of the variation compared with 80% for a non-linear equation, and this trend was confirmed for the dominant species, Typha latifolia. A modest recovery of emergent vegetation in 1999 following carp exclusion could have been predicted from declining water level alone, without invoking any effects of the biomanipulation. An unusually cool spring in 1997 delayed the migration of spawning planktivores into the marsh. This resulted in a grazer-mediated clear-water phase that coincided with a resurgence of the submersed aquatic vegetation (SAV) community in 1997, which declined again in 1999 when low water levels occurred. Even though decrease in water level was significantly related to increased suspended solids and greater light attenuation, light conditions appeared to have been adequate in marsh embayments to support SAV growth, according to a published relationship between maximum depth of SAV colonization and light extinction coefficient. I suggest that wave disturbance and propagule burial associated with shallow water depths may have been the main reasons for the decline of the SAV in 1999 and 2000.     

Revegetation,restoration and reptiles in rural landscapes: Insights from long‐term monitoring programmes in the temperate eucalypt woodlands of south‐eastern Australia

Over the past decade, there has been a concerted effort to better understand the distribution and abundance of reptiles in agricultural landscapes and to specifically evaluate their response to revegetation (tree and shrub plantings) and habitat restoration in the wheat‐sheep belt of south‐eastern Australia. This article reviews the response of reptiles to revegetation and woodland management and provides ten insights and lessons that can be applied to help improve reptile conservation in temperate eucalypt woodlands and fragmented agricultural landscapes in Australia. The review focuses primarily on revegetation programmes conducted by Landcare and Greening Australia, and management interventions funded by Local Land Services in NSW and Catchment Management Authorities in Victoria.     

Understanding the key characteristics and challenges of pine barrens restoration: insights from a Delphi survey of forest land managers and researchers

Pine barrens are open‐canopy ecological communities once prevalent on sandy soils across the northern Great Lakes Region of the United States and Canada, though fire suppression and plantation forestry have now reduced them to a few isolated areas. Efforts to restore pine barrens are underway on some public lands, but lack of knowledge on the social and ecological issues and challenges that affect these projects impedes fuller progress. As a precursor to designing a public preference survey for pine barrens restoration, we sought input from those with expert knowledge about pine barrens. Using a three‐round modified Delphi survey, forest land managers and researchers identified the key characteristics of pine barrens and important current and future management challenges. Key characteristics were related to fire, landscape structure, plant and animal species, soils, and social themes. Current and future challenges were related to landscape, invasive species, social, economic, climate change, and science themes. Four social issues (education, fire acceptance, fire risk, aesthetics) were rated among the top current challenges but none of them maintained prominence as future challenges. Potential explanations for this shift are that the experts felt these social concerns would be resolved in time or that other issues, such as development pressures and budgets for carrying out restoration, would become greater future challenges. Our approach can be used by managers and researchers to better understand the ecosystems they seek to restore and to communicate with public stakeholders about restoration efforts.     

从恢复生态学视角透析防护林衰退及其防治对策：以章古台地区樟子松林为例

针对防护林衰退问题,以章古台樟子松固沙林为案例,应用生态演替、干扰、种群密度等关键性恢复生态学理论和原则,对防护林在决策层面的设计要素的科学性及其与衰退的关系进行了分析和评价,认为大面积造林与地带性顶极的不吻合（即偏离生态学原则）,使防护林建设的目标、步骤、树种的组成和密度等出现了偏颇,成为防护林衰退的最深层次的原因,疏于管理和粗放经营以及频频发生的自然和人为干扰也是致衰的重要因素;据此提出深化对受损生态系统的认识、强化物质和能量的投入、建立干扰的防控体系等对策.文中还就人工植被建设目标与生态演替顶极类型的判别,以及偏途顶极在人工植被建设中的应用问题进行了讨论,一并作为对策以供参考.     

Identification of metabolic fluxes in hepatic cells from transient 13C-labeling experiments: Part II. Flux estimation

This contribution addresses the identification of metabolic fluxes and metabolite concentrations in mammalian cells from transient (13)C-labeling experiments. Whilst part I describes experimental set-up and acquisition of required metabolite and (13)C-labeling data, part II focuses on setting up network models and the estimation of intracellular fluxes. Metabolic fluxes were determined in glycolysis, pentose-phosphate pathway (PPP), and citric acid cycle (TCA) in a hepatoma cell line grown in aerobic batch cultures. In glycolytic and PPP metabolite pools isotopic stationarity was observed within 30 min, whereas in the TCA cycle the labeling redistribution did not reach isotopic steady state even within 180 min. In silico labeling dynamics were in accordance with in vivo (13)C-labeling data. Split ratio between glycolysis and PPP was 57%:43%; intracellular glucose concentration was estimated at 101.6 nmol per 10(6) cells. In contrast to isotopic stationary (13)C-flux analysis, transient (13)C-flux analysis can also be applied to industrially relevant mammalian cell fed-batch and batch cultures.     

Identification of metabolic fluxes in hepatic cells from transient 13C-labeling experiments: Part I. Experimental observations

An experimental set-up for acquiring metabolite and transient (13)C-labeling data in mammalian cells is presented. An efficient sampling procedure was established for hepatic cells cultured in six-well plates as a monolayer attached to collagen, which allowed simultaneous quenching of metabolism and extraction of the intracellular intermediates of interest. Extracellular concentrations of glucose, amino acids, lactate, pyruvate, and urea were determined by GC-MS procedures and were used for estimation of metabolic uptake and excretion rates. Sensitive LC-MS and GC-MS methods were used to quantify the intracellular intermediates of tricarboxylic acid cycle, glycolysis, and pentose phosphate pathway and for the determination of isotopomer fractions of the respective metabolites. Mass isotopomer fractions were determined in a transient (13)C-labeling experiment using (13)C-labeled glucose as substrate. The absolute amounts of intracellular metabolites were obtained from a non-labeled experiment carried out in exactly the same way as the (13)C-labeling experiment, except that the media contained naturally labeled glucose only. Estimation of intracellular metabolic fluxes from the presented data is addressed in part II of this contribution.