Grassland Restoration Projects Research Articles

Disembedding and Disentangling Grassland Valuation: Insights into Grassland Management Institutions and Ecological Research in China

After two decades of implementing top-down grassland restoration projects focused on reducing livestock numbers and pastoralist populations, the Chinese government’s well-funded efforts have not significantly reversed grassland degradation. This study reviews the institutional changes in grassland management over the past forty years, highlighting the Livestock and Grassland Double Contract Household Responsibility System of the early 1980s and the Grassland Ecological Reward and Compensation Policy introduced in 2011. It demonstrates how these institutional transformations have shaped pastoralists’ evolving understanding of grassland value and reveals that commodifying grassland’s economic and ecological value has led to the capitalization of nature, disembedding husbandry from grassland production, and undermining the effectiveness of conservation projects. This article also showcases the development of grassland ecology research in China, noting its increasing detachment from a holistic understanding of ecosystems and the interdisciplinary needs of management practices. The disjunction between grassland ecology research and practical management has resulted in a lack of techniques aligned with local ecological and socioeconomic contexts. This article champions active engagement with and protection of pastoralist communities to reintegrate grasslands’ true economic and ecological value into management practices, thereby effectively restoring degraded grasslands and achieving sustainable management.

Scale dependency of taxonomic and functional diversity in pristine and recovered loess steppic grasslands

Widespread campaigns on forest restoration and various tree planting actions lower the awareness of the importance of grasslands for carbon sequestration and biodiversity conservation. Even lower attention is given to the conservation of biodiversity and ecosystem functioning in remnants of ancient, so-called pristine grasslands. Pristine grasslands generally harbour high biodiversity, and even small patches can act as important refuges for many plant and animal species in urbanised or agricultural landscapes. Spontaneous succession of grassland is frequently viewed as a cost-effective tool for grassland restoration, but its applicability is strongly dependent on many local to landscape-scale factors, and the recovery is often slow. It is therefore essential to monitor the success of grassland restoration projects that rely on spontaneous succession. We compared the species diversity and functional attributes of pristine and recovered grasslands by studying the taxonomic and functional diversity in thirteen (8 pristine and 5 recovered) loess steppic grasslands using differently sized sampling plots from 0.01 to 100 m2. Our results indicate that there are remarkable differences in taxonomic and functional diversity between pristine and recovered grasslands. We also found that during secondary succession there is a likely functional saturation of the species assembly in the first few decades of recovery, and while patterns and structure of recovered grasslands became quite similar to those of pristine grasslands, species richness and diversity still remained much lower. Pristine grasslands support considerable plant diversity, and species composition is slow to recover if destroyed by agricultural land use. This underlines the importance of preserving existing pristine grassland remnants, which might serve as sources of species for future restoration measures.

Amount, distribution and controls of the soil organic carbon storage loss in the degraded China's grasslands

More than 80 % of China's grasslands are classified as degraded, and the loss of soil carbon storage due to degradation has a significant impact on China's terrestrial carbon sinks as well as carbon neutrality targets. The loss of soil carbon storage in degraded grasslands can serve as a benchmark for quantifying the carbon sequestration capacity of restored grasslands in the future. Here, above- and below-ground biomass, soil organic carbon (SOC) content at various depths (0–100 cm) and soil bulk density were collected from 226 degradation sequences around China. The above information was integrated and statistically analyzed to quantify the difference of SOC storage between the degraded and natural grassland at national scale. The result showed that grassland degradation led to a significant reduction in SOC storage across different depths. SOC (0–100 cm) of degraded grassland decreased by 39 % compared to that of natural grassland, ranging from 21 % in the lightly degraded sites to 59 % of the extremely degraded sites. 15 potential predictors were used to estimate the national amount of these differences of 0–20 cm depth SOC storage as 5.29 ± 1.59 Pg C. This considerable carbon storage gap implies the necessity of China's grassland restoration project in achieving carbon neutrality goals in the future.

Testing the hierarchy of predictability in grassland restoration across a gradient of environmental severity.

Ecological restoration is critical for recovering degraded ecosystems but is challenged by variable success and low predictability. Understanding which outcomes are more predictable and less variable following restoration can improve restoration effectiveness. Recent theory asserts that the predictability of outcomes would follow an order from most to least predictable from coarse to fine community properties (physical structure > taxonomic diversity > functional composition > taxonomic composition) and that predictability would increase with more severe environmental conditions constraining species establishment. We tested this "hierarchy of predictability" hypothesis by synthesizing outcomes along an aridity gradient with 11 grassland restoration projects across the United States. We used 1829 vegetation monitoring plots from 227 restoration treatments, spread across 52 sites. We fit generalized linear mixed-effects models to predict six indicators of restoration outcomes as a function of restoration characteristics (i.e., seed mixes, disturbance, management actions, time since restoration) and used variance explained by models and model residuals as proxies for restoration predictability. We did not find consistent support for our hypotheses. Physical structure was among the most predictable outcomes when the response variable was relative abundance of grasses, but unpredictable for total canopy cover. Similarly, one dimension of taxonomic composition related to species identities was unpredictable, but another dimension of taxonomic composition indicating whether exotic or native species dominated the community was highly predictable. Taxonomic diversity (i.e., species richness) and functional composition (i.e., mean trait values) were intermittently predictable. Predictability also did not increase consistently with aridity. The dimension of taxonomic composition related to the identity of species in restored communities was more predictable (i.e., smaller residuals) in more arid sites, but functional composition was less predictable (i.e., larger residuals), and other outcomes showed no significant trend. Restoration outcomes were most predictable when they related to variation in dominant species, while those responding to rare species were harder to predict, indicating a potential role of scale in restoration predictability. Overall, our results highlight additional factors that might influence restoration predictability and add support to the importance of continuous monitoring and active management beyond one-time seed addition for successful grassland restoration in the United States.

Rethinking local seed sourcing for the restoration of a foundational grass species in California

Restricting seed collecting to local populations is a common practice in restoration because it is assumed that most plants are adapted to local environmental conditions. However, there is still considerable debate about whether local seed collection should be the default seed‐provenancing strategy as the effects of climate change are increasingly considered in restoration planning. It is especially important to explore whether local seed provenance is necessary for dominant species used in restoration because the success of these projects often rests on these species. Stipa pulchra is one such species that is commonly used in grassland restoration projects in California. To explore how different seed‐provenancing strategies affected the establishment and growth of S. pulchra, we established three common garden experiments distributed across a latitudinal gradient in California. We collected seeds from seven wild populations, germinated seeds in a common greenhouse, then planted all populations at the three common gardens. We assessed growth and reproduction for 2 years. We found limited evidence that restricting seed sourcing to local populations increased the establishment of S. pulchra compared to seeds from more distant populations. Instead, we found evidence to support the use of regional admixture seed sourcing to increase resiliency to environmental variation. In particular, we found being sourced from a dry location during the dry 2018 season was a benefit, highlighting the importance of including dry‐adapted populations to increase climate resilience. Our experiment highlights the importance of exploring multiple seed‐provenancing methods when designing a project to improve long‐term success.

Alpine Grassland Degradation and Its Restoration in the Qinghai–Tibet Plateau

The alpine grasslands of the Qinghai–Tibet Plateau are one of the most famous grazing ecosystems in the world, providing a variety of ecosystem functions and services. The rate of grassland degradation has been slowed by the implementation of national grassland restoration projects, but the degradation of grasslands on the Qinghai–Tibet Plateau has not yet been fundamentally reversed, and some grasslands are still degraded to varying degrees. The main causes of grassland degradation on the Qinghai–Tibet Plateau are both human and natural factors. Human factors include overgrazing, over-cultivation, indiscriminate digging and mining, mineral resource development, infrastructure construction and use, and tourism development. Natural factors include climate change, wildlife destruction, pests, etc. Based on the principles of restoration ecology, a number of effective practices and integrated management responses for restoring degraded grasslands have been developed on the Qinghai–Tibet Plateau. The degraded grassland restoration practices include fencing, fertilization, sown grassland establishment, rodent control, and grazing management. Based on these practices, the comprehensive restoration of degraded grasslands and the establishment and sustainable management of sown grasslands in the alpine grasslands of the Qinghai–Tibet Plateau should be further strengthened, and research on the mechanisms of grassland degradation and restoration should be further developed.

“The ASO grassland-restoration project”, to maintain and restore the ASO semi-natural grassland using local certified plants

“The ASO grassland-restoration project”, to maintain and restore the ASO semi-natural grassland using local certified plants

Grassland restoration by local seed mixtures: New evidence from a practical 15‐year restoration study

AbstractAimLocal seed mixtures are frequently used to restore species‐rich grasslands. However, it has hardly been tested whether local seed mixtures can actually be applied successfully in grassland restoration practice at larger scales and long‐term. To close this gap, we report the results of a large‐scale restoration study in which grasslands were restored about 15 years ago using different local seed mixtures.LocationBavaria, SE Germany.MethodsTo evaluate the efficacy of the local seed mixtures, we compared the species composition of seed mixtures and current vegetation. We then tested whether restoration success depends on site characteristics such as the size and shape (rectangle or stripe) of the grassland, restoration procedures such as topsoil removal, seed density and land use, or species habitat preferences for light, water and nutrients, and species life span (annual, perennial).ResultsOn average, the current vegetation contained 62.4% of all species that were present in the local seed mixtures. Species from the local seed mixtures made up on average 69.1% of the total cover in the established vegetation, whereby the species composition of the local seed mixture and vegetation differed significantly from each other. The probability that a sown species would establish increased with seed density up to 300 seeds/m². Furthermore, habitat preferences significantly affected species establishment chances, with species requiring full illumination, dry and nutrient‐poor soil being more successful during restoration, reflecting the high proportion of sites with topsoil removal prior to seeding in our study. Annual species had significantly lower establishment chances compared with their perennial counterparts.ConclusionsOur study provides another piece of evidence that local seed mixtures can be applied successfully in large‐scale grassland restoration projects. We provide several practical recommendations of how such practices can be further improved by using specific seed densities and creating new local seed mixtures using species that are ecologically more suitable to the restored sites.

Hay transfer is a nature-based and sustainable solution for restoring grassland biodiversity

As we enter the United Nations Decade on Ecosystem Restoration, there is an increasing need for finding nature-based solutions for the restoration of grasslands across the globe. Besides seed sowing, alternative restoration methods that build on locally available propagule sources, such as hay transfer, should also be considered and given high priority. The transfer of hay from a donor site to the restoration site serves a double aim by introducing target species and suppressing weeds. We tested the applicability of hay transfer in restoring species-rich grassland in a former cropland in Hungary, over six years of post-restoration monitoring from 2015 to 2020. We sampled the plant species composition of the three donor sites (target state of restoration) and the area surrounding the restoration site. We found that six year after restoration, a species-rich grassland developed with 42 successfully established specialist species that had a cover of 45%. Most specialist species became established from the hay from the second to the sixth year, but the surrounding areas also provided additional propagule sources. Among the eight analysed functional traits, seed mass of the transferred species was the best predictor of the establishment of specialists, and we found that small-seeded species had an establishment advantage in the first years after restoration. Our results suggest that hay transfer can be a suitable nature-based solution for local grassland restoration projects and its potential should be utilized especially in regions where suitable donor sites are present in sufficient quantity and quality.

Possibilities of restoration of natural or seminatural grasslands

The number of natural grassland restoration projects increased in the last decade in Hungary, and probably the area of restored grasslands will be significantly extended in the next years due to New National Rural Development Program. To contribute to the success of this activity, in this paper we review the most important theoretical and practical aspects of natural grassland restoration methods. In the course of grassland restoration, habitats dominated by grasses and/or sedges have been restored in place of arable lands. In order to perform “natural” restoration, we should consider the ecological conditions of the landscape, and reconstruct natural or seminatural grasslands including of native plant species. Essentially, rehabilitation of natural landscape is supported also by creating new seminatural grassland patches. The basic principles of the natural grassland restoration are:
 1. When a spontaneous secondary succession starts to proceed on an abandoned field without invasion of any alien plant species, the re-ploughing of the abandoned field has to be ignored.
 2. Generally, the old fields surrounded by species-rich natural or seminatural grassland pathes can succesfully be restorated. Then, as a consequence of newly restored vegetation patches the recovery of the whole landscape can be accelerated. Furthermore, by restoring isolated grassland patches surrounded by arable lands a more diverse landscape pattern could be developed.
 3. Spontaneous secondary succession of grasslands should be assisted.
 4. The development of typical species composition of a seminatural grassland can be promoted by methods of spreaded hay. For successful process the hay has to be cut in a habitat type similar to ones that will be restored.
 5. Applying seed-mix for sowing can be useful to prevent spreading weeds drastically in the early stages of succession.
 6. Ideally, the seed-mix is originated from own harvesting or gathering from similar (or the same) habitats. If it is not possible, commercially available seed-mix can be applied, in which the dominant species is the same as in the restored habitat, with similar proportion.
 7. Seed-mix consists of alien species has to be avoided.
 8. If the composition or structure of the restored grassland is not appropriate after some years, the renewal of the grassland could be necessary. During the improvement process the reploughing of the restored grassland is avoided, but spreading seeds or hay, and direct sowing can be applied.
 9. The loading of nutrient is not necessary in any stages of grassland restoration.
 10. Applying chemicals is avoided; any herbicides can be used only when extensive invasion of alien plant species occurs.
 11. The mechanical intrusions on soil are also avoided.
 12. The restored grasslands is required regular or continuous management, which could be a preserving mowing or moderate grazing. The aspects of nature conservation should be considered.

How much does is cost to restore a grassland?

Knowledge of the costs involved to implement a restoration project is imperative to most cost‐effectively allocate restoration funds, aid the prioritization of efforts, minimize waste, and conceive realistic objectives. When integrated with information regarding ecological and other socioeconomic indicators, consistent and complete cost‐reporting not only informs evaluations of overall project success but also aids practitioners and academics alike to assess the suitability of restoration innovations prior to implementation. Yet, despite awareness of the lack of cost information in restoration literature for at least 30 years, cost reporting, and thus analysis of cost variability, is still rare. This study discusses the results of a literature review and questionnaire conducted with grassland restoration practitioners internationally in order to better understand the costs related to grassland restoration, and to attempt to explain sources of variability in cost data. Only 12 scientific papers reporting cost data were retrieved, and although widely distributed, only 15 responses to the survey were registered. Northern hemisphere temperate grassland restoration projects dominated. Costs for grassland restoration were extremely variable, with costs of individual restoration activities/phases ranging from a few dollars to thousands of dollars. This variation derives from the highly context‐dependent nature of ecological restoration. The lack of cost data may hinder implementation of broader scale restoration projects, and mechanisms should be sought to collect standardized information and make it better available.

Evaluating ecological outcomes from environmental stewardship initiatives: A comparative analysis of approaches

Understanding the extent to which stewardship initiatives achieve objectives of enhanced ecological outcomes is important for enhancing effectiveness and efficiency of environmental management initiatives. Alternative approaches – community science, stakeholder perceptions, and remote sensing - are emerging in lieu of the conventional approach of collecting field data that present different benefits and drawbacks and to date have not been directly compared. This research compared the use of four approaches to evaluating ecological outcomes of a grassland restoration project on a 2 ha Niagara Parks Commission property in Ontario, Canada. We collected three levels of quantitative data, from general site assessments to species-specific data using standardized questionnaires and multi-spectral imagery from a remotely piloted aircraft system. We found that community scientists and stakeholders provided comparable general site assessments to the field data, but that as the assessments became more detailed, differences emerged. Further, remotely sensed data were assessed and provided a more positive site assessment than any other method. Experiences and knowledge of nature did not influence assessments by community scientists or stakeholders. Our findings show that for overall site assessments, community scientists and stakeholders may be able to provide a reasonably accurate assessment. If monitoring and evaluation needs (either research-based or practical) extend beyond a broad assessment, use of a field expert or multiple methods of data collection may be warranted.

Hierarchy of environmental factors driving restoration of dry grasslands: A multi‐site analysis

AbstractQuestionsQuantification of the role of particular factors driving restoration may improve our understanding of restoration processes and thus lead to a better design of restoration projects. We investigated how restoration methods, soil characteristics, time since sowing or abandonment, proximity effects, and climate influence vegetation changes and restoration success in the restored grasslands. We particularly asked: (a) which of the studied environmental factors influence the course of restoration of dry grasslands and how much; (b) what is their hierarchy; and (c) what are the implications for ecological restoration?LocationWhite Carpathians Protected Landscape Area, eastern Czech Republic.MethodsWe studied 82 dry grasslands restored on former arable land, either sown with a regional or commercial clover–grass seed mixture or left to spontaneous succession, and compared them with ancient dry grasslands as reference sites. Data were processed using Detrended Correspondence Analysis and Canonical Correspondence Analysis. Generalized linear models (GLMs) were used to test the relationships between two measures of restoration success (number of colonizing target species and Bray–Curtis similarity between restored and reference vegetation) and the environmental factors.ResultsThe ordination results demonstrate some convergence of grasslands restored with different methods toward reference sites. Using regional seed mixtures led to a higher participation of dry grassland species, while using commercial seed mixtures and spontaneous succession favored mesic grassland species. All tested groups of environmental variables exhibited some significant effects on the course of restoration. Their hierarchy varied depending on the vegetation characteristic we used but generally, restoration method and soil factors appeared to be the most important, followed by time since sowing or abandonment, climatic factors, and proximity effects.ConclusionsWhen planning grassland restoration projects, we have to consider especially soil characteristics and landscape context, i.e., location of the restored site in the landscape matrix and climatic conditions, and select proper restoration methods.

Ant‐hill heterogeneity and grassland management

Abstract1. In many grasslands, some ants act as ecological engineers to produce long‐lasting soil structures which have a considerable influence on the patterns and dynamics of plant, vertebrate and invertebrate species. They promote species richness and diversity.2. The yellow meadow ant, Lasius flavus, is the most abundant allogenic ecological engineer in grazed European grasslands, producing vegetated long‐lasting mounds. It is so frequent and abundant that it must be regarded as a keystone species. Grassland restoration projects frequently attempt to re‐introduce grasslands on abandoned arable fields. When this ant does not colonize naturally it should be introduced. It probably limits the abundance of grasses in a similar manner to hemi‐parasitic plant species.3. Ant‐hills make a distinctive contribution to grassland heterogeneity. Measurements on mounds in a single grassland over 45 years document the dynamics of the same 200+ ant‐hills in volume, surface area and basal area. As the mounds aged, they increased in size and took over a higher proportion of the grassland surface. Occupied mounds continued to grow, abandoned mounds decreased in volume and some disappeared entirely.4. Four plant species favoured by the soil heaped by the ants were also monitored. Two woody perennials grew up through heaped soil and two short‐lived species colonized its surface. As the mounds became occupied, some of these species significantly increased, and when they were abandoned some decreased.5. In a grassland, the ant‐hill population provides a fluctuating subset of plant and animal species which are characteristic of temporary habitats. This seems likely to reduce the rate of local extinctions which might otherwise result from fluctuations in grazing pressure. In conservation settings, ant‐hills should be introduced or maintained where possible, and considered in planning grassland maintenance and management.

Remote sensing inversion of grassland aboveground biomass based on high accuracy surface modeling

Accurate and effective accounting of grassland aboveground biomass (AGB) is essential for grassland carbon storage accounting and pastoral agriculture sustainability. In this study, we combined AGB field survey data and remote sensing data to build a suitable model to estimate the grassland AGB in the Three-River Source Region (TRSR) of China. Three machine learning models were used to simulate the grassland AGB from 2001 to 2019, including support vector machine (SVM), random forest (RF), and high accuracy surface modeling (HASM). The results show that (1) the HASM achieved better results than the RF and SVM models (R2 = 0.8459 > 0.72 > 0.5858; RMSE = 29 < 41 < 56), and the HASM results reproduce the spatial distribution characteristics of the biomass well. The subsequent spatiotemporal analysis of the AGB conducted in this study was based on the results of the HASM. (2) The highest AGB was located in the eastern and central-southern parts of the TRSR, and the lowest AGB was distributed in the western region. (3) The overall change in the AGB revealed that the percentage of the area that experienced a significant increase in AGB (21%) was larger than that of the area that experienced a significant decrease (13%), and the stable areas accounted for 66% of the total area. The grassland AGB increased by 1 g/m2/yr during 2001–2019. (4) The factors driving the changes in the AGB were analyzed. Overall, the warm and wet climate conditions promoted grass growth in most regions of the TRSR. (5) However, the biomass decreased in some regions with warm and wet conditions. For example, overgrazing and increased populations of grazing led to significant biomass decreases in the towns of Ziketang and Heka in Xinghai County. In this study, the grassland AGB was simulated based on the HASM model, with a high accuracy and a spatial resolution of 500 m. The results of this study provide a scientific basis for grassland resource protection and the highly effective implementation of grassland restoration projects in China.

The ASO grassland-restoration project, to maintain and restore the ASO semi-natural grassland ―Ecological Revegetation Study Group, The Japanese Society of Revegetation Technology―

The ASO grassland-restoration project, to maintain and restore the ASO semi-natural grassland ―Ecological Revegetation Study Group, The Japanese Society of Revegetation Technology―

Activity Report of “the ASO grassland-restoration project” 2018

Activity Report of “the ASO grassland-restoration project” 2018

地域植物資源の活用と保全の試み・阿蘇小規模崩壊地復元プロジェクト ―日本緑化工学会 生態・環境緑化研究部会―

地域植物資源の活用と保全の試み・阿蘇小規模崩壊地復元プロジェクト ―日本緑化工学会 生態・環境緑化研究部会―

Ecosystem Services and Their Relationships in the Grain-for-Green Programme—A Case Study of Duolun County in Inner Mongolia, China

Grassland restoration projects are currently being implemented to mitigate human disturbance to the natural environment and reduce grassland degradation. China’s Grain-for-Green Programme (GFGP), including one project implemented in Duolun County, China, in 2000, has significantly improved the overall ecological health of this region. Using a modeling approach, this study quantified changes in four ecosystem services (ESs), including Net Primary Production (NPP), soil conservation (SC), water yield (WY), and sandstorm prevention (SP), in Duolun County between 2000 and 2016. We found the total NPP, water yield, and soil conservation increased by 80.44%, 248.2%, and 12.2%, respectively, during this period, while the sandstorm prevention decreased by 55.9%. Unlike other areas of GFGP implementation, the improvement of the ecological environment in Duolun County is largely attributed to the increased of vegetation coverage (88%) instead of land use circulation (12%). We found the grassland is a factor that reduces the trade-off while this effect was related with the grassland coverage. Future policies should be based on the mechanisms of vegetation underlying the ESs change and the relationships of ESs in order to achieve sustainable provision of ESs.

Introduction of “the ASO grassland-restoration project”, to maintain and restore the ASO semi-natural grassland”

Introduction of “the ASO grassland-restoration project”, to maintain and restore the ASO semi-natural grassland”