To see the other types of publications on this topic, follow the link: Grasslands ecosystems.
Journal articles on the topic 'Grasslands ecosystems'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Grasslands ecosystems.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
Valkó, Orsolya, Rocco Labadessa, Salza Palpurina, Sabina Burrascano, Atushi Ushimaru, and Stephen Venn. "Conservation and diversity of Palaearctic grasslands – Editorial to the 5th EDGG special issue in Hacquetia." Hacquetia 18, no. 2 (December 1, 2019): 143–46. http://dx.doi.org/10.2478/hacq-2019-0011.
Full textAbstract:
Abstract Palaearctic grasslands are diverse and dynamic ecosystems that are in the focus of ecology, conservation biology and agronomy. This special issue is dedicated to the biodiversity and conservation issues of Palaearctic grasslands and was initiated by the Eurasian Dry Grassland Group members attending the 14th Eurasian Dry Grassland Conference (EDGC) at Sulmona, Italy in 2018. The papers in this special issue cover a wide range of grassland ecosystems from mountain dry grasslands to lowland loess grasslands, feathergrass steppes and wet grasslands, and focus on the biodiversity values and conservation issues of Palaearctic grasslands. We believe that this compilation will contribute to a better understanding of the ecology of grasslands and support their more effective conservation.
2
Kang, Le, Xingguo Han, Zhibin Zhang, and Osbert Jianxin Sun. "Grassland ecosystems in China: review of current knowledge and research advancement." Philosophical Transactions of the Royal Society B: Biological Sciences 362, no. 1482 (February 22, 2007): 997–1008. http://dx.doi.org/10.1098/rstb.2007.2029.
Full textAbstract:
Grasslands are the dominant landscape in China, accounting for 40% of the national land area. Research concerning China's grassland ecosystems can be chronologically summarized into four periods: (i) pre-1950s, preliminary research and survey of grassland vegetation and plant species by Russians, Japanese and Western Europeans, (ii) 1950–1975, exploration and survey of vegetation, soils and topography as part of natural resource inventory programmes by regional and national institutions mainly led by the Chinese Academy of Sciences, (iii) 1976–1995, establishment of field stations for long-term ecological monitoring and studies of ecosystem processes, (iv) 1996–present, comprehensive studies of community dynamics and ecosystem function integrating multi-scale and multidisciplinary approaches and experimental manipulations. Major findings of scientific significance in China's grassland ecosystem research include: (i) improved knowledge on succession and biogeochemistry of the semi-arid and temperate grassland ecosystems, (ii) elucidation of life-history strategies and diapause characteristics of the native grasshopper species as one of the key grassland pests, and (iii) development of effective management strategies for controlling rodent pests in grassland ecosystems. Opportunities exist for using the natural grasslands in northern China as a model system to test ecosystem theories that so far have proven a challenge to ecologists worldwide.
3
Gharun, Mana, Lukas Hörtnagl, Eugénie Paul-Limoges, Shiva Ghiasi, Iris Feigenwinter, Susanne Burri, Kristiina Marquardt, et al. "Physiological response of Swiss ecosystems to 2018 drought across plant types and elevation." Philosophical Transactions of the Royal Society B: Biological Sciences 375, no. 1810 (September 7, 2020): 20190521. http://dx.doi.org/10.1098/rstb.2019.0521.
Full textAbstract:
Using five eddy covariance flux sites (two forests and three grasslands), we investigated ecosystem physiological responses to the 2018 drought across elevational gradients in Switzerland. Flux measurements showed that at lower elevation sites (below 1000 m.a.s.l.; grassland and mixed forest) annual ecosystem productivity (GPP) declined by approximately 20% compared to the previous 2 years (2016 and 2017), which led to a reduced annual net ecosystem productivity (NEP). At the high elevation sites, however, GPP increased by approximately 14% and as a result NEP increased in the alpine and montane grasslands, but not in the subalpine coniferous forest. There, increased ecosystem respiration led to a reduced annual NEP, despite increased GPP and lengthening of the growing period. Among all ecosystems, the coniferous forest showed the most pronounced negative stomatal response to atmospheric dryness (i.e. vapour pressure deficit, VPD) that resulted in a decline in surface conductance and an increased water-use efficiency during drought. While increased temperature enhanced the water-use efficiency of both forests, de-coupling of GPP from evapotranspiration at the low-elevation grassland site negatively affected water-use efficiency due to non-stomatal reductions in photosynthesis. Our results show that hot droughts (such as in 2018) lead to different responses across plants types, and thus ecosystems. Particularly grasslands at lower elevations are the most vulnerable ecosystems to negative impacts of future drought in Switzerland. This article is part of the theme issue ‘Impacts of the 2018 severe drought and heatwave in Europe: from site to continental scale’.
4
Feng, Jiguang, Jingsheng Wang, Yanjun Song, and Biao Zhu. "Patterns of soil respiration and its temperature sensitivity in grassland ecosystems across China." Biogeosciences 15, no. 17 (September 3, 2018): 5329–41. http://dx.doi.org/10.5194/bg-15-5329-2018.
Full textAbstract:
Abstract. Soil respiration (Rs), a key process in the terrestrial carbon cycle, is very sensitive to climate change. In this study, we synthesized 54 measurements of annual Rs and 171 estimates of Q10 value (the temperature sensitivity of soil respiration) in grasslands across China. We quantitatively analyzed their spatial patterns and controlling factors in five grassland types, including temperate typical steppe, temperate meadow steppe, temperate desert steppe, alpine grassland, and warm, tropical grassland. Results showed that the mean (±SE) annual Rs was 582.0±57.9 g C m−2 yr−1 across Chinese grasslands. Annual Rs significantly differed among grassland types, and was positively correlated with mean annual temperature, mean annual precipitation, soil temperature, soil moisture, soil organic carbon content, and aboveground biomass, but negatively correlated with soil pH (p<0.05). Among these factors, mean annual precipitation was the primary factor controlling the variation of annual Rs among grassland types. Based on the overall data across Chinese grasslands, the Q10 values ranged from 1.03 to 8.13, with a mean (±SE) of 2.60±0.08. Moreover, the Q10 values varied largely within and among grassland types and soil temperature measurement depths. Among grassland types, the highest Q10 derived by soil temperature at a depth of 5 cm occurred in alpine grasslands. In addition, the seasonal variation of soil respiration in Chinese grasslands generally cannot be explained well by soil temperature using the van't Hoff equation. Overall, our findings suggest that the combined factors of soil temperature and moisture would better predict soil respiration in arid and semi-arid regions, highlight the importance of precipitation in controlling soil respiration in grasslands, and imply that alpine grasslands in China might release more carbon dioxide to the atmosphere under climate warming.
5
Tomaškin, Ján, Ján Jančovič, Ľuboš Vozár, and Judita Tomaškinová. "The effect of mineral fertilization on belowground plant biomass of grassland ecosystems." Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis 61, no. 5 (2013): 1431–40. http://dx.doi.org/10.11118/actaun201361051431.
Full textAbstract:
Aim of the work was to determine the effect of different doses of mineral fertilization on belowground and aboveground plant biomass production of three different types of grasslands, to state R:S ratio (root:shoot) and turnover period of belowground plant biomass of grasslands. In the contribution, we assess production of underground biomass, tillering zone and aboveground biomass on three types of grasslands – permanent grassland (PG), over-sown grassland (OSG) and temporary grassland (TG) in sub-mountain area of central Slovakia. There were applied four levels of mineral nutrition in each grassland (non-fertilized variant, var. 30 kg.ha−1P and 60 kg.ha−1 K. var. 90 kg.ha−1 N + P30K60, var. 180 kg.ha−1 N + P30K60). The root biomass has the most significant share in the total biomass of grasslands (49.9–54.2 %), followed by tillering zone (33.3–36.0 %) and with the lowest share of aboveground biomass (11.9–16.8 %). A dominant share of root biomass and tillering zone ensure significant extra-productive functions of grasslands that contribute to the stability of agriculture landscape. We recorded the lowest amounts of root mass on TG (7.31 t.ha−1) and OSG (7.76 t.ha−1), the highest amounts on PG (8.52 t.ha−1). The specific nitrogen stimulating influence on root biomass production has been proven. Production of tillering zone was lower on OSG and TG (5.11 or 5.42 t.ha−1), significantly higher on PG (5.72 t.ha−1). We observed a significantly higher production of tillering zone with variants which were fertilized with nitrogen than on non-fertilized and PK fertilized. The lowest harvests of aboveground biomass were noticed on TG (5.80 t.ha−1), significantly higher on PG and OSG (6.35 or 6.54 t.ha−1). Mineral nutrition had a significant impact on production of aboveground biomass.R:S ratio of the assessed grasslands achieved the values from 4.02 to 5.16. Higher values on PG (5.16) are indicating its higher resistance to drought. Turnover time of root biomass was the longest on PG 3.5–5.0 years, on OSG and TG 2.5–3.5 years. Based on achieved results, we recommend using the fodder plants cultivation system on PG or OSG. Permanent grasslands are proved as ecologically more stable and more resistant to drought than temporary grasslands; they can together with optimal mineral nutrition provide adequate production of root biomass (8.5 t.ha−1) and a harvest of aboveground biomass (6.3 t.ha−1).
6
Chang, Juan, Jiaxi Tian, Zengxin Zhang, Xi Chen, Yizhao Chen, Sheng Chen, and Zheng Duan. "Changes of Grassland Rain Use Efficiency and NDVI in Northwestern China from 1982 to 2013 and Its Response to Climate Change." Water 10, no. 11 (November 19, 2018): 1689. http://dx.doi.org/10.3390/w10111689.
Full textAbstract:
The grasslands in arid and semi-arid regions rely heavily on the use of rain, thus, improving rain use efficiency (RUE) is essential for securing sustainable development of grassland ecosystems in these areas with limited rainfall. In this study, the spatial and temporal variabilities of RUE for grassland ecosystems over Northwestern China during 1982–2013 were analyzed using the normalized difference vegetation index (NDVI) and precipitation data. Results showed that: (1) Although grassland area has decreased gradually over the past 30 years, the NDVI in most areas showed that the vegetation was gradually restored; (2) The trends of RUE increased in the east of Northwestern China and decreased in the west of Northwestern China. However, the trends of RUE for the high-coverage grasslands (vs. low-coverage grassland) increased (decreased) significantly over the past 30 years. (3) The RUE for the grasslands was positively correlated with air temperature, while it was negatively correlated with the change of annual mean precipitation in northwestern China. Moreover, the obvious RUE increasing trends were found in the vegetation restoration areas, while the RUE decreasing trends appeared in the vegetation degradation areas. This study will be helpful for understanding the impacts of climate change on securing the sustainable development of grassland ecosystems in arid and semi-arid regions.
7
Yang, Y. H., J. Y. Fang, D. L. Guo, C. J. Ji, and W. H. Ma. "Vertical patterns of soil carbon, nitrogen and carbon: nitrogen stoichiometry in Tibetan grasslands." Biogeosciences Discussions 7, no. 1 (January 5, 2010): 1–24. http://dx.doi.org/10.5194/bgd-7-1-2010.
Full textAbstract:
Abstract. Vertical patterns of soil organic carbon (SOC), total nitrogen (TN) and C:N stoichiometry are crucial for understanding biogeochemical cycles in high-altitude ecosystems, but remain poorly understood. In this study, we investigated vertical distributions of SOC and TN as well as their stoichiometric relationships in alpine grasslands on the Tibetan Plateau using data of 405 profiles surveyed from 135 sites across the plateau during 2001–2004. Our results showed that, both SOC and TN in alpine grasslands decreased with soil depth, while C:N ratio did not exhibit significant change along soil profile. The associations of SOC and TN content (amount per area) with environmental factors diminished with soil depth. Soil carbon content was nearly proportional to nitrogen content with a slope of 1.04 across various various grassland types. The slope did not differ significantly between alpine steppe and alpine meadow or between alpine grasslands and global ecosystems, and also did not reveal significant differences among various soil depth intervals, suggesting that soil carbon-nitrogen coupling is irrespective of ecosystem types and soil depths.
8
Imran, Hafiz Ali, Damiano Gianelle, Michele Scotton, Duccio Rocchini, Michele Dalponte, Stefano Macolino, Karolina Sakowska, Cristina Pornaro, and Loris Vescovo. "Potential and Limitations of Grasslands α-Diversity Prediction Using Fine-Scale Hyperspectral Imagery." Remote Sensing 13, no. 14 (July 6, 2021): 2649. http://dx.doi.org/10.3390/rs13142649.
Full textAbstract:
Plant biodiversity is an important feature of grassland ecosystems, as it is related to the provision of many ecosystem services crucial for the human economy and well-being. Given the importance of grasslands, research has been carried out in recent years on the potential to monitor them with novel remote sensing techniques. In this study, the optical diversity (also called spectral diversity) approach was adopted to check the potential of using high-resolution hyperspectral images to estimate α-diversity in grassland ecosystems. In 2018 and 2019, grassland species composition was surveyed and canopy hyperspectral data were acquired at two grassland sites: Monte Bondone (IT-MBo; species-rich semi-natural grasslands) and an experimental farm of the University of Padova, Legnaro, Padua, Italy (IT-PD; artificially established grassland plots with a species-poor mixture). The relationship between biodiversity (species richness, Shannon’s, species evenness, and Simpson’s indices) and optical diversity metrics (coefficient of variation-CV and standard deviation-SD) was not consistent across the investigated grassland plant communities. Species richness could be estimated by optical diversity metrics with an R = 0.87 at the IT-PD species-poor site. In the more complex and species-rich grasslands at IT-MBo, the estimation of biodiversity indices was more difficult and the optical diversity metrics failed to estimate biodiversity as accurately as in IT-PD probably due to the higher number of species and the strong canopy spatial heterogeneity. Therefore, the results of the study confirmed the ability of spectral proxies to detect grassland α-diversity in man-made grassland ecosystems but highlighted the limitations of the spectral diversity approach to estimate biodiversity when natural grasslands are observed. Nevertheless, at IT-MBo, the optical diversity metric SD calculated from post-processed hyperspectral images and transformed spectra showed, in the red part of the spectrum, a significant correlation (up to R = 0.56, p = 0.004) with biodiversity indices. Spatial resampling highlighted that for the IT-PD sward the optimal optical pixel size was 1 cm, while for the IT-MBo natural grassland it was 1 mm. The random pixel extraction did not improve the performance of the optical diversity metrics at both study sites. Further research is needed to fully understand the links between α-diversity and spectral and biochemical heterogeneity in complex heterogeneous ecosystems, and to assess whether the optical diversity approach can be adopted at the spatial scale to detect β-diversity. Such insights will provide more robust information on the mechanisms linking grassland diversity and optical heterogeneity.
9
Breitkreuz, Sarah, Laio Silva Sobrinho, Leah Stachniak, and Scott Chang. "Can the Adaptive Multi-Paddock Grazing System Increase Carbon Sequestration in Alberta's Grassland Soils?" Alberta Academic Review 2, no. 2 (September 11, 2019): 13–14. http://dx.doi.org/10.29173/aar52.
Full textAbstract:
Natural grasslands cover around 40% of the Earth’s surface and play an important role as a source of ecological goods and services. By sequestering around 30% of terrestrial global carbon, grasslands play a critical part in the alleviation of climate change. Despite their ecological significance, grasslands have been reduced to a fraction of their original extent. In Canada, up to 70% of grasslands have been destroyed, making it the most endangered ecosystem in North America. What remains is often intensely grazed and a diverse ecosystem of wild animals is replaced by domestic livestock. The continuous application of poor grazing management by ranchers is one of the main causes for the depletion of natural grasslands, resulting in the release of stored soil carbon back into the atmosphere. Fortunately, 60-70% of the depleted carbon can be re-sequestered through the adoption of improved grazing management, thus improving grassland ecosystems. The Adaptive Multi-Paddock (AMP) grazing system is an example of improved grazing management. AMP grazing is a system in which livestock is frequently rotated between multiple fenced paddocks. Compared to conventional grazing practices (Non-AMP), the AMP system is a favorable solution which can improve carbon sequestration in world wide grasslands soils– and in turn, contribute to the mitigation of climate change. By regenerating grassland ecosystems, AMP grazing could potentially aid in creating a more sustainable, resilient agroecosystem. Our goal is to study the effect of AMP grazing on soil organic carbon (SOC) sequestration in Canadian grasslands. First, we collected soil cores from 30 study sites located throughout the grassland ecoregions in Canada. Each site consisted of a pair of ranches: one AMP and one Non-AMP. Second, we analyzed the soil cores for total carbon using an elemental analyzer. There does not seem to be any substantial difference in total carbon between AMP and Non-AMP systems, however we have yet to differentiate between soil organic carbon and soil inorganic carbon. Once we distinguish the two variables we will be able to confirm the effectiveness of the AMP grazing system in increasing carbon sequestration in Canadian grasslands.
Literature Cited:
Derner, J. D., & Schuman, G. E. (2007). Carbon sequestration and rangelands: a synthesis of land management and precipitation effects. Journal of soil and water conservation, 62(2), 77-85.
Gauthier, D. A., & Wiken, E. B. (2003). Monitoring the conservation of grassland habitats, Prairie Ecozone, Canada. Environmental Monitoring and Assessment, 88(1-3), 343-364.
Samson, F., & Knopf, F. (1994). Roundtable: prairie conservation in North America. BioScience, 44(6), 418-421
Kraus, D. (2016). Why Canada’s Prairies are the World’s Most Endangered Ecosystem. Retrieved from: http://www.natureconservancy.ca/en/blog/archive/grasslands-the-most.html#.XUnsE-hKi70
Lal, R. (2002). Soil carbon dynamics in cropland and rangeland. Environmental pollution, 116(3), 353-362
Teague, W. R. (2018). Forages and pastures symposium: Cover crops in livestock production: Whole-system approach: Managing grazing to restore soil health and farm livelihoods. Journal of animal science, 96(4), 1519-1530.
10
Bai, W. M., M. Zhou, Y. Fang, and W. H. Zhang. "Differences in spatial and temporal root lifespan of temperate steppes across Inner Mongolia grasslands." Biogeosciences Discussions 12, no. 23 (December 15, 2015): 19999–20023. http://dx.doi.org/10.5194/bgd-12-19999-2015.
Full textAbstract:
Abstract. Lifespan of fine roots plays important roles in regulating carbon (C) cycling in terrestrial ecosystems. Determination of root lifespan and elucidation of its regulatory mechanism in different plant communities are essential for accurate prediction of C cycling from ecosystem to regional scales. Temperate steppes in Inner Mongolia grasslands have three major types, i.e., Stipa krylovii, Stipa grandis and Stipa breviflora grasslands. There have been no studies to compare the root dynamics among the three types of grasslands. In the present study, we determined root lifespan of the three grasslands using the rhizotron. We found that root lifespan differed substantially among the three types of grasslands within the temperate steppes of Inner Mongolia, such that root lifespan of Stipa breviflora > Stipa grandis > Stipa krylovii grasslands. Root lifespan across the three types of grasslands in the Inner Mongolian temperate steppes displayed a similar temporal pattern, i.e. lifespan of the roots produced in spring and autumn was shortest and longest, respectively, whereas lifespan of summer-produced roots was between that of roots produced in spring and autumn. The spatial and temporal differences in root lifespan across the three types of grasslands were mainly determined by contents of soluble sugars in roots of the dominant species. The differences in root lifespan across the major types of grasslands and different seasons highlight the necessity to take into account these differences in the prediction of C cycling within grassland ecosystem by the simulating model.
11
Soubry, Irini, Thuy Doan, Thuan Chu, and Xulin Guo. "A Systematic Review on the Integration of Remote Sensing and GIS to Forest and Grassland Ecosystem Health Attributes, Indicators, and Measures." Remote Sensing 13, no. 16 (August 18, 2021): 3262. http://dx.doi.org/10.3390/rs13163262.
Full textAbstract:
It is important to protect forest and grassland ecosystems because they are ecologically rich and provide numerous ecosystem services. Upscaling monitoring from local to global scale is imperative in reaching this goal. The SDG Agenda does not include indicators that directly quantify ecosystem health. Remote sensing and Geographic Information Systems (GIS) can bridge the gap for large-scale ecosystem health assessment. We systematically reviewed field-based and remote-based measures of ecosystem health for forests and grasslands, identified the most important ones and provided an overview on remote sensing and GIS-based measures. We included 163 English language studies within terrestrial non-tropical biomes and used a pre-defined classification system to extract ecological stressors and attributes, collected corresponding indicators, measures, and proxy values. We found that the main ecological attributes of each ecosystem contribute differently in the literature, and that almost half of the examined studies used remote sensing to estimate indicators. The major stressor for forests was “climate change”, followed by “insect infestation”; for grasslands it was “grazing”, followed by “climate change”. “Biotic interactions, composition, and structure” was the most important ecological attribute for both ecosystems. “Fire disturbance” was the second most important for forests, while for grasslands it was “soil chemistry and structure”. Less than a fifth of studies used vegetation indices; NDVI was the most common. There are monitoring inconsistencies from the broad range of indicators and measures. Therefore, we recommend a standardized field, GIS, and remote sensing-based approach to monitor ecosystem health and integrity and facilitate land managers and policy-makers.
12
Gong, Y. M., A. Mohammat, X. J. Liu, K. H. Li, P. Christie, F. Fang, W. Song, et al. "Response of carbon dioxide emissions to sheep grazing and N application in an alpine grassland – Part 2: Effect of N application." Biogeosciences 11, no. 7 (April 3, 2014): 1751–57. http://dx.doi.org/10.5194/bg-11-1751-2014.
Full textAbstract:
Abstract. Widespread nitrogen (N) enrichment resulting from anthropogenic activities has led to great changes in carbon exchange between the terrestrial biosphere and the atmosphere. Grassland is one of the most sensitive ecosystems to N deposition. However, the effect of N deposition on ecosystem respiration (Re) in grasslands has been conducted mainly in temperate grasslands, which are limited largely by water availability, with few studies focused on alpine grasslands that are primarily constrained by low temperatures. Failure to assess the magnitude of the response in Re outside the growing season (NGS) in previous studies also limits our understanding of carbon exchange under N deposition conditions. To address these knowledge gaps we used a combination of static closed chambers and gas chromatography in an alpine grassland from 2010 to 2011 to test the effects of N application on ecosystem respiration (Re) both inside and outside the growing season. There was no significant change in CO2 emissions under N application. Re outside the growing season was at least equivalent to 9.4% of the CO2 fluxes during the growing season (GS). Annual Re was calculated to be 279.0–403.9 g CO2 m−2 yr−1 in Bayinbuluk alpine grasslands. In addition, our results indicate that soil temperature was the dominant abiotic factor regulating variation in Re in the cold and arid environment. Our results suggest that short-term N additions exert no significant effect on CO2 emissions in alpine grassland.
13
Fuhlendorf, Samuel D., Craig A. Davis, R. Dwayne Elmore, Laura E. Goodman, and Robert G. Hamilton. "Perspectives on grassland conservation efforts: should we rewild to the past or conserve for the future?" Philosophical Transactions of the Royal Society B: Biological Sciences 373, no. 1761 (October 22, 2018): 20170438. http://dx.doi.org/10.1098/rstb.2017.0438.
Full textAbstract:
Grasslands are among the most imperilled biomes of the world. Identifying the most appropriate framework for restoring grasslands is dependent on the objectives of restoration, which is inherently determined by human priorities. Debates over the appropriate conservation model for grasslands have often focused on which species of herbivores should be the focus of restoration efforts. Here we discuss three perspectives of herbivore-based conservation in North American grasslands. First, the Pleistocene rewilding perspective is based upon the idea that early humans contributed to the demise of megafauna that were important to the evolution and development of many of North America's grasslands; therefore, their aim of restoration is rewilding of landscapes to pre-human times. Second, the bison rewilding perspective considers American bison a keystone herbivore that is culturally and ecologically important to North American grasslands. A third perspective focuses on restoring the pattern and processes of herbivory on grasslands and is less concerned about which herbivore is introduced to the landscape. We evaluate each of these three conservation perspectives in terms of a framework that includes a human domain, an herbivore domain and a biophysical domain. While all conservation perspectives partly address the three domains, they all fall short in key areas. Specifically, they fail to recognize that past, current and future humans are intimately linked to grassland patterns and processes and will continue to play a role in structuring grasslands. Furthermore, these perspectives seem to only superficially consider the role of fragmentation and climate change in influencing grassland patterns and processes. As such, we argue that future grassland conservation efforts must depend on the development of a model that better integrates societal, economic and policy objectives and recognizes climate change, fragmentation and humans as an integral part of these ecosystems. This article is part of the theme issue ‘Trophic rewilding: consequences for ecosystems under global change’.
14
Van den Hoof, Catherine, Michel Verstraete, and Robert Scholes. "Differing Responses to Rainfall Suggest More Than One Functional Type of Grassland in South Africa." Remote Sensing 10, no. 12 (December 18, 2018): 2055. http://dx.doi.org/10.3390/rs10122055.
Full textAbstract:
Grasslands, which represent around 40% of the terrestrial area, are mostly located in arid and semi-arid zones. Semiarid ecosystems in Africa have been identified as being particularly vulnerable to the impacts of increased human pressure on land, as well as enhanced climate variability. Grasslands are indeed very responsive to variations in precipitation. This study evaluates the sensitivity of the grassland ecosystem to precipitation variability in space and time, by identifying the factors controlling this response, based on monthly precipitation data from Climate Hazards Group InfraRed Precipitation with Station data (CHIRPS) and the Fraction of Absorbed Photosynthetically Active Radiation (FAPAR) data from the Multi-angle Imaging SpectroRadiometer-High Resolution (MISR-HR) datasets, used as proxy for productivity, at 60 grassland sites in South Africa. Our results show that MISR-HR products adequately capture the spatial and temporal variability in productivity at scales that are relevant to this study, and they are therefore a good tool to study climate change impacts on ecosystem at small spatial scales over large spatial and temporal domains. We show that combining several determinants and accounting for legacies improves our ability to understand patterns, identify areas of vulnerability, and predict the future of grassland productivity. Mean annual precipitation is a good predictor of mean grassland productivity. The grasslands with a mean annual rainfall above about 530 mm have a different functional response to those receiving less than that amount of rain, on average. On the more arid and less fertile soils, large inter-annual variability reduces productivity. Our study suggests that grasslands on the more marginal soils are the most vulnerable to climate change.
15
Fayiah, Moses, ShiKui Dong, Sphiwe Wezzie Khomera, Syed Aziz Ur Rehman, Mingyue Yang, and Jiannan Xiao. "Status and Challenges of Qinghai–Tibet Plateau’s Grasslands: An Analysis of Causes, Mitigation Measures, and Way Forward." Sustainability 12, no. 3 (February 4, 2020): 1099. http://dx.doi.org/10.3390/su12031099.
Full textAbstract:
Grassland ecosystems on the Qinghai–Tibet Plateau (QTP) provide numerous ecosystem services and functions to both local communities and the populations living downstream through the provision of water, habitat, food, herbal medicines, and shelter. This review examined the current ecological status, degradation causes, and impacts of the various grassland degradation mitigation measures employed and their effects on grassland health and growth in the QTP. Our findings revealed that QTP grasslands are continually being degraded as a result of complex biotic and abiotic drivers and processes. The biotic and abiotic actions have resulted in soil erosion, plant biomass loss, soil organic carbon loss, a reduction in grazing and carrying capacity, the emergence of pioneer plant species, loss of soil nutrients, and an increase in soil pH. A combination of factors such as overgrazing, land-use changes, invasive species encroachment, mining activities, rodent burrowing activities, road and dam constructions, tourism, migration, urbanization, and climate change have caused the degradation of grasslands on the QTP. A conceptual framework on the way forward in tackling grassland degradation on the QTP is presented together with other appropriate measures needed to amicably combat grassland degradation on the QTP. It is recommended that a comprehensive and detailed survey be carried out across the QTP to determine the percentage of degraded grasslands and hence, support a sound policy intervention.
16
Zhao, Qian, Lei Yang, Xin Wang, Runcheng Bi, and Qindi Zhang. "Effects of two typical revegetation methods on soil moisture in the semi-arid Loess Plateau, China." Hydrology Research 50, no. 5 (July 17, 2019): 1453–62. http://dx.doi.org/10.2166/nh.2019.011.
Full textAbstract:
Abstract Understanding the effects of vegetation on soil moisture is vital to the ecosystem restoration in water-restricted areas. For this study, the effects of introduced revegetation and natural revegetation on soil water (0–1.8 m) were investigated in the Chinese Loess Plateau, which was based on an in situ vegetation removal experiment and two years of soil moisture monitoring. The results indicated that under introduced revegetation, pasture grassland had lower soil moisture but higher temporal variations over the growing season. Compared with abandoned farmlands and native grasslands under natural revegetation, pasture grasslands revealed greater negative effects on deep soil moisture (1–1.8 m), which was difficult to recover following soil desiccation. In contrast, for abandoned farmlands and native grasslands, the surface soil moisture (0–0.4 m) was mainly impacted, which was easily replenished through rainfall events. These outcomes implied that natural revegetation, rather than introduced revegetation, should be the first choice in water-limited regions toward the rehabilitation of degraded ecosystems.
17
Price, Jodi N., Megan K. Good, Nick L. Schultz, Lydia K. Guja, and John W. Morgan. "Multivariate drivers of diversity in temperate Australian native grasslands." Australian Journal of Botany 67, no. 5 (2019): 367. http://dx.doi.org/10.1071/bt18190.
Full textAbstract:
Disturbance has been considered essential for maintaining biodiversity in temperate grassy ecosystems in Australia. This has been particularly well demonstrated for inter-tussock plant species in C4 Themeda-dominated grasslands in mesic environments. Disturbance is also thought crucial to maintain the structure of preferred habitat for some animals. Relationships between disturbance and diversity may be contingent on ecosystem productivity, but little is known about the generality of the disturbance-promoting-diversity paradigm across the range of temperate grasslands. To date, the disturbance-promoting-diversity paradigm has taken a univariate approach to the drivers of biodiversity; rainfall is seen as a key driver of productivity, which then drives diversity, mediated by disturbance. We argue that this framework is too simplistic as biodiversity drivers are multivariate. We suggest that the accumulation of phytomass (live and dead plant material) is an important determinant of diversity in grassy ecosystems and that phytomass accumulation is governed by multiple drivers (of which disturbance is just one). For fauna, it is structure – not biomass – that determines habitat suitability, and this can be moderated by both abiotic and biotic drivers. The assumption that there is a consistent effect of disturbance on diversity through the range of temperate grassland settings in southern Australia ignores the likelihood that biodiversity also responds to other factors such as spatial heterogeneity in the environment, resource availability and climatic variation. We developed a conceptual model of the multivariate drivers of grassland diversity that explores mechanisms underpinning patterns of species richness. Despite four decades of research, it is clear that our understanding of the multivariate drivers of diversity across the range of temperate grasslands in Australia is still incomplete. Further research into the conditions under which disturbance is required to maintain biodiversity in grasslands is integral to conservation planning in these endangered systems.
18
Yamaura, Yuichi, Ayu Narita, Yoshinobu Kusumoto, Atsushi J. Nagano, Ayumi Tezuka, Toru Okamoto, Hikaru Takahara, Futoshi Nakamura, Yuji Isagi, and David Lindenmayer. "Genomic reconstruction of 100 000-year grassland history in a forested country: population dynamics of specialist forbs." Biology Letters 15, no. 5 (May 29, 2019): 20180577. http://dx.doi.org/10.1098/rsbl.2018.0577.
Full textAbstract:
Grassland ecosystems worldwide have been extensively converted to other land uses and are globally imperiled. Because many grasslands have been maintained by human activities, understanding their origin and history is fundamentally important to better contemporary management. However, existing methods to reconstruct past vegetation can produce contrasting views on grassland history. Here, we inferred demographic histories of 40 populations of four grassland forb species throughout Japan using high-resolution genome sequences and model-flexible demographic simulation based on the site frequency spectrum. Although two species showed a slight decline in population size between 100 000–10 000 years ago, our results suggest that population sizes of studied species have been maintained within the range of 0.5–2.0 times the most recent estimates for at least 100 000 years across Japan. Our results suggest that greater than 90% declines in Japanese grasslands and subsequent losses of grassland species in the last 100 years are geologically and biologically important and will have substantial consequences for Japanese biota and culture. People have had critical roles in maintaining disturbance-dependent grassland ecosystems and biota in this warm and wet forested country. In these contexts, disturbances associated with forest harvesting and traditional extensive farming have the potential to maintain grassland ecosystems and can provide important opportunities to reconcile resource production and conservation of grassland biodiversity.
19
Roby, Matthew C., Russell L. Scott, Greg A. Barron-Gafford, Erik P. Hamerlynck, and David J. P. Moore. "Environmental and Vegetative Controls on Soil CO2 Efflux in Three Semiarid Ecosystems." Soil Systems 3, no. 1 (January 8, 2019): 6. http://dx.doi.org/10.3390/soilsystems3010006.
Full textAbstract:
Soil CO2 efflux (Fsoil) is a major component of the ecosystem carbon balance. Globally expansive semiarid ecosystems have been shown to influence the trend and interannual variability of the terrestrial carbon sink. Modeling Fsoil in water-limited ecosystems remains relatively difficult due to high spatial and temporal variability associated with dynamics in moisture availability and biological activity. Measurements of the processes underlying variability in Fsoil can help evaluate Fsoil models for water-limited ecosystems. Here we combine automated soil chamber and flux tower data with models to investigate how soil temperature (Ts), soil moisture (θ), and gross ecosystem photosynthesis (GEP) control Fsoil in semiarid ecosystems with similar climates and different vegetation types. Across grassland, shrubland, and savanna sites, θ regulated the relationship between Fsoil and Ts, and GEP influenced Fsoil magnitude. Thus, the combination of Ts, θ, and GEP controlled rates and patterns of Fsoil. In a root exclusion experiment at the grassland, we found that growing season autotrophic respiration accounted for 45% of Fsoil. Our modeling results indicate that a combination of Ts, θ, and GEP terms is required to model spatial and temporal dynamics in Fsoil, particularly in deeper-rooted shrublands and savannas where coupling between GEP and shallow θ is weaker than in grasslands. Together, these results highlight that including θ and GEP in Fsoil models can help reduce uncertainty in semiarid ecosystem carbon dynamics.
20
Zhao, Jinling, Jiale Chen, Honghui Wu, Linghao Li, and Fengjuan Pan. "Effects of Mowing Frequency on Soil Nematode Diversity and Community Structure in a Chinese Meadow Steppe." Sustainability 13, no. 10 (May 17, 2021): 5555. http://dx.doi.org/10.3390/su13105555.
Full textAbstract:
Soil nematodes are one of the most important components in terrestrial ecosystems and the critical factor driving the belowground process. The grasslands of Northeast China have been subject to mowing for ages, which theoretically should have had substantial effects on the processes associated with soil nematodes. However, relevant studies have barely been conducted to date. This study examined variations in soil nematode abundance, biomass, diversity, and community structure, with respect to varying mowing frequencies. The results showed that a higher mowing frequency significantly reduced the abundance of soil nematodes, biomass, diversity, and community structure stability in the ecosystem, while intermediate mowing frequency enhanced these parameters to different extents. Our findings indicate that the changing patterns of the nematode indices with mowing frequency conform to the intermediate disturbance theory. This study provides a theoretical basis for formulating grassland-related management measures and maintaining the stability of grassland ecosystems.
21
Holúbek, Ivan, Peter Hric, Peter Kovár, and Andrea Boháčiková. "Financing of grassland habitats in the Slovak Republic in 2010–2016." Acta Regionalia et Environmentalica 15, no. 1 (May 1, 2018): 22–27. http://dx.doi.org/10.2478/aree-2018-0005.
Full textAbstract:
Abstract The grasslands in the Slovak Republic are divided into 7 categories that have different way and conditions of management to protect and maintain them. From the area of 1,239,777 hectares of habitats in SR and payments per hectare, we calculated the amount of financial support that represents 130,265,701 € for the A-G habitats in 2010-2016. Based on the data about potential use of grassland habitats in livestock feeding (mountain meadows and alluvial meadows), the production potential of C 3.12 t.ha-1biotope E 4.25 t.ha-1of dry matter was calculated, as a result of 5-years long experiment of the Department of Grassland Ecosystems and Forage Crops of SUA in Nitra. We calculated the direct costs for the production of hay dry matter, which reached 116.78 €.ha-1in the meadows, and 71.11 €.ha-1in valleys. Direct costs per 1 hectare of hay dry production are with a support covered on 111.0% of mountain meadows and 74% of meadows. The annual value of ecosystem services of grassland habitats reached 579,789,008 €. Subsidies for permanent grassland habitats stimulate the economy of agricultural subjects and protect the biodiversity of permanent grasslands.
22
Yang, Ting Ting, Peng Li, Peng Tao Liu, and Xin Hong Wu. "Distribution of Grassland Biomass Carbon Storage in China." Advanced Materials Research 518-523 (May 2012): 183–88. http://dx.doi.org/10.4028/www.scientific.net/amr.518-523.183.
Full textAbstract:
Grassland ecosystems plays a very important role in the global carbon cycle，But measured data is very lack. In this paper, based on the ground survey data of grassland in fourteen provinces in 2008 and satellite remote sensing data, biomass carbon storage in grassland ecosystem in China is estimated. The main conclusions are as follows: China's total grassland area is about 331.41×104 km2, the total biomass carbon storage in grassland ecosystem in China in 2008 was 951.73 TgC, The carbon storage in aboveground and belowground were 161.99 and 789.74 TgC respectively. Carbon storage of Underground was about 5 times more than that of aboveground. China's grasslands are mainly located in the northern arid and semi-arid regions and Qinghai-Tibet Plateau. Inner Mongolia has the highest total vegetation carbon storage. Heilongjiang province is the area which has the highest above-ground biomass density, while the lowest area is Ningxia province. warm-temperate shrub-tussock provides the largest portion of carbon storage in Chinese grassland vegetation (29.66%).
23
Dwitri Malik, Annas, Maulida Isfahani Nurillah, Parikesit, Susanti Withaningsih, and Ratna Wingit. "Carbon Sequestration Potentials of Man-made Grasslands under Different Pattern of Plantation Stands in West Bandung Regency, Indonesia." E3S Web of Conferences 249 (2021): 03011. http://dx.doi.org/10.1051/e3sconf/202124903011.
Full textAbstract:
Alternatives of vegetations to store carbon need to be encouraged considering that forests are threatened by widespread destructions. One such vegetation is grasslands which have the potential for carbon storage and to reduce CO2 concentration in the atmosphere. At present, many enterprises have designed grasslands for many purposes. Grasslands at Cikalong Wetan and Little Farmers, West Bandung Regency were established under different pattern of plantation stands. The purpose of this research was to study the potential of carbon stock in grassland vegetation at these locations. Based on RaCSA method, the tree biomass was determined by nondestructive collection of density and basal area of trees, then calculated by an allometric equation. The ground cover biomass was determined by destructive collection of grass and roots. Total measured biomass was multiplied by 46% to obtain carbon storage. Based on the results, the potential of carbon stock in Little Farmers grassland (159,540 ton ha-1) is higher than in Cikalong Wetan (14,482 ton ha-1). Carbon stored in tree biomass gives the highest contribution to overall carbon stock potential in Little Farmers (94.84%) while carbon stored in below-ground understorey biomass gives the highest contribution in Cikalong Wetan (52.13 %). Different management of grasslands and pattern of plantation stands resulting a different contribution of carbon stock in every carbon pool. In order to maintain the carbon sequestration potentials of these locations, an agroforestry management such as agri-silviculture need to be encouraged. This study gives a comparison of the carbon sequestration potentials between two man-made grassland ecosystems. For many enterprises this study will aid in a management planning of man-made grassland in terms of ecosystem services, that is carbon sequestration.
24
Gracheva, Raisa, Elena Belonovskaya, and Vera Vinogradova. "Mountain grassland ecosystems on abandoned agricultural terraces (Russia, North Caucasus)." Hacquetia 17, no. 1 (June 1, 2018): 61–71. http://dx.doi.org/10.1515/hacq-2017-0010.
Full textAbstract:
Abstract Terraces represent one of the most common agricultural landscape elements in the mountainous regions of the North Caucasus. In the Central and West Caucasus, most of the arable terraces were converted into grasslands for grazing and haymaking 60-70 years ago and then abandoned or underused during the last 20-25 years. The role of abandoned terraces in maintaining the diversity of grasslands of the mountain slopes was studied in the case of eight terraces of different types. Plant communities of subalpine meadows and meadow steppes were distinguished on the terraces depending mainly on slope steepness at the same altitudes and to a lesser extent on the slope aspect. In general, the grasslands of the terrace platforms and those of original unterraced slopes had similar traits. At that, the mesophilous communities on the rich soils of terrace edges and scarp communities similar to vegetation of steep slopes with eroded soils create regular patterns on the terraced slopes. Thus, former agricultural terraces conditioning geodiversity also contribute to the diversity of plant communities and landscape fragmentation. The current increase of temperature and humidity may lead to a reduction of climatic differences of the slopes, and the further convergence of grassland communities can be assumed.
25
Yan, Junjie, Guangpeng Zhang, Xiaoya Deng, Hongbo Ling, Hailiang Xu, and Bin Guo. "Does Climate Change or Human Activity Lead to the Degradation in the Grassland Ecosystem in a Mountain-Basin System in an Arid Region of China?" Sustainability 11, no. 9 (May 7, 2019): 2618. http://dx.doi.org/10.3390/su11092618.
Full textAbstract:
In mountain-basin systems in the arid region, grasslands are sensitive to the impacts of climate change and human activities. In this study, we aimed to resolve two key scientific issues: (1) distinguish and explain the laws of grassland ecosystem deterioration in a mountain-basin system and identify the key factors related; and (2) evaluate whether damaged grasslands ecosystem have the potential for natural revegetation. Hence, by combining spatial analysis with statistical methods, we studied the trends of the deterioration of the grassland ecosystem and its spatial characteristics in Kulusitai, a mountain-basin system in the arid region of Northwest China. According to our results, vegetation coverage and productivity exhibited significant decreasing trends, while the temperature vegetation drought index (TVDI) exhibited a significant increasing trend. Drainage of groundwater, because of increase in irrigation for the expanded irrigated area around Kulusitai, and climate warming were the critical triggers that leaded to the soil drought. Soil drought and overgrazing, resulting from the impact of human activities, were the main factors responsible for the deterioration of the grassland ecosystems. However, limiting the number of livestock to a reasonable scale and reducing the irrigated area may help to increase the soil moisture, thus promoting the germination of soil seed banks and facilitating the normal growth of grassland vegetation. Furthermore, based on analysis of the phenology of the grassland vegetation, the reasonable period for harvesting and storage is from July 29 to August 5. The results of this study provide a scientific basis and practical guide for restoring mountain-basin grassland systems in arid regions.
26
Kavwele, Cyrus M., Johnstone K. Kimanzi, and Mwangi J. Kinyanjui. "Impacts of Bush Encroachment on Wildlife Species Diversity, Composition, and Habitat Preference in Ol Pejeta Conservancy, Laikipia, Kenya." International Journal of Ecology 2017 (2017): 1–6. http://dx.doi.org/10.1155/2017/5620125.
Full textAbstract:
Savannah ecosystems are currently facing a biome shift that changes grasslands to woody dominated landscapes, attributable to habitat degradation. In Ol Pejeta Conservancy (OPC), Euclea divinorum, an unpalatable and invasive woody species, is expanding to former savannah ecosystems with potential effects on herbivores key resources, wildlife species diversity, composition, and habitat use. We investigated wildlife species diversity, composition, and habitat preference or avoidance by wildlife in the conservancy. Infrared camera traps were deployed at the centroids of 2 km by 2 km, 50 cm above ground surface for 14 days and nights with 9 camera traps in each habitat type. Shannon wiener index revealed that wildlife species diversity was highest in E. divinorum dominated habitats and lowest in open grassland. Hierarchical Cluster Analysis revealed level of similarity in wildlife species composition between E. divinorum and mixed bushland. Jacobs index revealed that E. divinorum and mixed bushland were avoided by all guilds; however E. divinorum was significantly avoided while A. drepanolobium and open grassland were both preferred by all guilds. However, A. drepanolobium dominated habitats were significantly preferred compared to open grasslands. The findings are useful in management of sustainable ecosystems.
27
Wang, Ling, Manuel Delgado-Baquerizo, Deli Wang, Forest Isbell, Jun Liu, Chao Feng, Jushan Liu, et al. "Diversifying livestock promotes multidiversity and multifunctionality in managed grasslands." Proceedings of the National Academy of Sciences 116, no. 13 (March 8, 2019): 6187–92. http://dx.doi.org/10.1073/pnas.1807354116.
Full textAbstract:
Increasing plant diversity can increase ecosystem functioning, stability, and services in both natural and managed grasslands, but the effects of herbivore diversity, and especially of livestock diversity, remain underexplored. Given that managed grazing is the most extensive land use worldwide, and that land managers can readily change livestock diversity, we experimentally tested how livestock diversification (sheep, cattle, or both) influenced multidiversity (the diversity of plants, insects, soil microbes, and nematodes) and ecosystem multifunctionality (including plant biomass production, plant leaf N and P, above-ground insect abundance, nutrient cycling, soil C stocks, water regulation, and plant–microbe symbiosis) in the world’s largest remaining grassland. We also considered the potential dependence of ecosystem multifunctionality on multidiversity. We found that livestock diversification substantially increased ecosystem multifunctionality by increasing multidiversity. The link between multidiversity and ecosystem multifunctionality was always stronger than the link between single diversity components and functions. Our work provides insights into the importance of multitrophic diversity to maintain multifunctionality in managed ecosystems and suggests that diversifying livestock could promote both multidiversity and ecosystem multifunctionality in an increasingly managed world.
28
Guo, Zheng Gang, Tian Gang Liang, Xing Yuan Liu, and Fu Jun Niu. "A new approach to grassland management for the arid Aletai region in Northern China." Rangeland Journal 28, no. 2 (2006): 97. http://dx.doi.org/10.1071/rj05018.
Full textAbstract:
Land degradation in the arid Aletai Region in northern China is not only detrimental to animal production, but also reduces the ability to conserve water resources by destabilising the catchments of rivers which affects runoff, thus, threatening the sustainable use of these grasslands. A new approach to grassland management based on carrying capacity and ecological services value of grassland types, using an index of classification management (ICG), was designed to ensure the sustainability of grassland ecosystems. In this approach, grassland is classified into 3 management sectors. The first is conservation grassland, which is mainly devoted to ecological and social values; the second is the moderately productive grassland, dedicated to multiple benefits by rational use; and the third is intensively productive grassland, focusing on maximum economic effect. For the arid Aletai region, no intensively productive grassland was available. Conservation grassland occupied 2.5 million ha, accounted for 25.4% of grassland area, and included alpine meadow, mountain meadow, mountain meadow steppe, mountain steppe and flat meadow. In these grasslands, grazing should be eliminated to allow restoration of degenerated areas, protect grasslands with important ecological values from destruction, and to further improve the environment. Moderately productive grassland covered 7.3 million ha, and the grassland types were alpine steppe, mountain desert steppe, plain desert steppe, steppe desert, and plain desert. Agricultural measures, such as fertiliser and irrigation application, should be used to enhance the productivity of these grasslands.
29
Lu, Fei, Huifeng Hu, Wenjuan Sun, Jiaojun Zhu, Guobin Liu, Wangming Zhou, Quanfa Zhang, et al. "Effects of national ecological restoration projects on carbon sequestration in China from 2001 to 2010." Proceedings of the National Academy of Sciences 115, no. 16 (April 16, 2018): 4039–44. http://dx.doi.org/10.1073/pnas.1700294115.
Full textAbstract:
The long-term stressful utilization of forests and grasslands has led to ecosystem degradation and C loss. Since the late 1970s China has launched six key national ecological restoration projects to protect its environment and restore degraded ecosystems. Here, we conducted a large-scale field investigation and a literature survey of biomass and soil C in China’s forest, shrubland, and grassland ecosystems across the regions where the six projects were implemented (∼16% of the country’s land area). We investigated the changes in the C stocks of these ecosystems to evaluate the contributions of the projects to the country’s C sink between 2001 and 2010. Over this decade, we estimated that the total annual C sink in the project region was 132 Tg C per y (1 Tg = 1012 g), over half of which (74 Tg C per y, 56%) was attributed to the implementation of the projects. Our results demonstrate that these restoration projects have substantially contributed to CO2 mitigation in China.
30
Hubert-Moy, Laurence, Jeanne Thibault, Elodie Fabre, Clémence Rozo, Damien Arvor, Thomas Corpetti, and Sébastien Rapinel. "Mapping Grassland Frequency Using Decadal MODIS 250 m Time-Series: Towards a National Inventory of Semi-Natural Grasslands." Remote Sensing 11, no. 24 (December 17, 2019): 3041. http://dx.doi.org/10.3390/rs11243041.
Full textAbstract:
Semi-natural grasslands are perennial ecosystems and an important part of agricultural landscapes that are threatened by urbanization and agricultural intensification. However, implementing national grassland conservation policies remains challenging because their inventory, based on short-term observation, rarely discriminate semi-natural permanent from temporary grasslands. This study aims to map grassland frequency at a national scale over a long period using Moderate Resolution Imaging Spectroradiometer (MODIS) 250 m satellite time-series. A three-step method was applied to the entire area of metropolitan France (543,940 km²). First, land-use and land-cover maps—including grasslands—were produced for each year from 2006–2017 using the random forest classification of MOD13Q1 and MYD13Q1 products, which were calibrated and validated using field observations. Second, grassland frequency from 2006–2017 was calculated by combining the 12 annual maps. Third, sub-pixel analysis was performed using a reference layer with 20 m spatial resolution to quantify percentages of land-use and land-cover classes within MODIS pixels classified as grassland. Results indicate that grasslands were accurately modeled from 2006–2017 (F1-score 0.89–0.93). Nonetheless, modeling accuracy varied among biogeographical regions, with F1-score values that were very high for Continental (0.94 ± 0.01) and Atlantic (0.90 ± 0.02) regions, high for Alpine regions (0.86 ± 0.04) but moderate for Mediterranean regions (0.62 ± 0.10). The grassland frequency map for 2006–2017 at 250 m spatial resolution provides an unprecedented view of stable grassland patterns in agricultural areas compared to existing national and European GIS layers. Sub-pixel analysis showed that areas modeled as grasslands corresponded to grassland-dominant areas (60%–94%). This unique long-term and national monitoring of grasslands generates new opportunities for semi-natural grassland inventorying and agro-ecological management.
31
Williams, Jennifer M., Donald J. Brown, and Petra B. Wood. "Responses of Terrestrial Herpetofauna to Persistent, Novel Ecosystems Resulting from Mountaintop Removal Mining." Journal of Fish and Wildlife Management 8, no. 2 (July 1, 2017): 387–400. http://dx.doi.org/10.3996/102016-jfwm-079.
Full textAbstract:
Abstract Mountaintop removal mining is a large-scale surface mining technique that removes entire floral and faunal communities, along with soil horizons located above coal seams. In West Virginia, the majority of this mining occurs on forested mountaintops. However, after mining ceases the land is typically reclaimed to grasslands and shrublands, resulting in novel ecosystems. In this study, we examined responses of herpetofauna to these novel ecosystems 10–28 y postreclamation. We quantified differences in species-specific habitat associations, (sub)order-level abundances, and habitat characteristics in four habitat types: reclaimed grassland, reclaimed shrubland, forest fragments in mined areas, and nonmined intact forest. Habitat type accounted for 33.2% of the variation in species-specific captures. With few exceptions, forest specialists were associated with intact forest and fragmented forest sites, while habitat generalists were either associated with grassland and shrubland sites or were distributed among all habitat types. At the (sub)order level, salamander (Order Urodela) captures were highest at fragmented and intact forest sites, frog and toad (Order Anura) captures were lowest at intact forest sites, and snake (Suborder Serpentes) captures were highest at shrubland sites. Habitat type was a strong predictor for estimated total abundance of urodeles, but not for anurans or snakes. Tree stem densities in grasslands differed from the other three habitat types, and large trees (>38 cm diameter at breast height) were only present at forest sites. Overstory vegetation cover was greater in forested than in reclaimed habitat types. Ground cover in reclaimed grasslands was distinct from forest treatments with generally less woody debris and litter cover and more vegetative cover. It is important to consider the distributions of habitat specialists of conservation concern when delineating potential mountaintop mine sites, as these sites will likely contain unsuitable habitat for forest specialists for decades or centuries when reclaimed to grassland or shrubland.
32
Timoney, Kevin P. "Threatened dry grasslands in the continental boreal forests of Wood Buffalo National Park: commentary." Canadian Journal of Botany 77, no. 7 (November 5, 1999): 913–17. http://dx.doi.org/10.1139/b99-120.
Full textAbstract:
There are three primary types of graminoid-dominated communities in or near Wood Buffalo National Park, Canada: freshwater meadows and marshes composed of Calamagrostis canadensis (Michx.) Beauv., Carex atherodes Spreng., Carex aquatilis Wahlenb., Scolochloa festucacea (Willd.) Link, and Poa L.; saline meadows composed of Hordeum jubatum L., Puccinellia nuttalliana (Schult.) A.S. Hitchc.,Agropyron trachycaulum (Link) Malte, Calamagrostis stricta (Timm) Koeler, and Calamagrostis inexpansa A. Gray; and dry grasslands composed of Agropyron trachycaulum, Stipa L., Carex siccata Dewey, Carex obtusata Lilj., and Koeleria macrantha (Ledeb.) J.A. Schultes f. Except for the Peace Point area, it is not known whether dry grasslands have declined in areal extent. Including various wetlands under "dry grasslands", and concluding that these areas no longer support dry grassland is misleading. Dry grasslands exist in Wood Buffalo National Park, but most graminoid-dominated communities in the park are, and have been, freshwater and saline meadows and marshes. A clear understanding of the ecological factors operating in these different ecosystems is critical to informed management.Key words: fire, grassland, prairie, vegetation, wetland, Wood Buffalo National Park.
33
Retallack, Gregory J. "Middle Miocene fossil plants from Fort Ternan (Kenya) and evolution of African grasslands." Paleobiology 18, no. 4 (1992): 383–400. http://dx.doi.org/10.1017/s0094837300010964.
Full textAbstract:
New evidence from fossil plants at the Middle Miocene fossil quarry near Fort Ternan, Kenya, together with that from paleosols, allow reconstruction of a mosaic of early successional woodland (on Dhero paleosols), grassy woodland (on Chogo clay eroded phase and ferruginized nodule variant paleosols) and wooded grassland (on type Chogo and Onuria clay paleosols). This grassy open vegetation was on a high plateau of phonolite at the foot of a carbonatite-nephelinite stratovolcano, which probably supported dry Afromontane forest, alpine meadows, and marsh. This earliest savanna-mosaic vegetation yet documented from Africa, was probably recruited from dry lateritic soils elsewhere in Africa during climatic drying and cooling some 15 Ma. These early grassland ecosystems were very different from Early Miocene forest ecosystems of East Africa, but not altogether like modern grasslands either. Already present were grasses with dense growth and rich in silica bodies, and abundant antelope with moderately high crowned teeth and cursorial limb structure. These mammalian adaptations to grasslands, however, were not nearly so pronounced as they are in modern African grassland faunas, which include zebra and other Asiatic immigrants, as well as antelope. Grasses of the subfamily Chloridoideae and supertribe Panicanae were common in tropical Africa by Middle Miocene time, if not much earlier, but there is not yet evidence so far back in time for the grass supertribe Andropogonae which is now dominant in seasonally arid, overgrazed, and burned African grasslands.
34
Chang, J. F., N. Viovy, N. Vuichard, P. Ciais, T. Wang, A. Cozic, R. Lardy, et al. "Incorporating grassland management in ORCHIDEE: model description and evaluation at 11 eddy-covariance sites in Europe." Geoscientific Model Development 6, no. 6 (December 20, 2013): 2165–81. http://dx.doi.org/10.5194/gmd-6-2165-2013.
Full textAbstract:
Abstract. This study describes how management of grasslands is included in the Organizing Carbon and Hydrology in Dynamic Ecosystems (ORCHIDEE) process-based ecosystem model designed for large-scale applications, and how management affects modeled grassland–atmosphere CO2 fluxes. The new model, ORCHIDEE-GM (grassland management) is enabled with a management module inspired from a grassland model (PaSim, version 5.0), with two grassland management practices being considered, cutting and grazing. The evaluation of the results from ORCHIDEE compared with those of ORCHIDEE-GM at 11 European sites, equipped with eddy covariance and biometric measurements, shows that ORCHIDEE-GM can realistically capture the cut-induced seasonal variation in biometric variables (LAI: leaf area index; AGB: aboveground biomass) and in CO2 fluxes (GPP: gross primary productivity; TER: total ecosystem respiration; and NEE: net ecosystem exchange). However, improvements at grazing sites are only marginal in ORCHIDEE-GM due to the difficulty in accounting for continuous grazing disturbance and its induced complex animal–vegetation interactions. Both NEE and GPP on monthly to annual timescales can be better simulated in ORCHIDEE-GM than in ORCHIDEE without management. For annual CO2 fluxes, the NEE bias and RMSE (root mean square error) in ORCHIDEE-GM are reduced by 53% and 20%, respectively, compared to ORCHIDEE. ORCHIDEE-GM is capable of modeling the net carbon balance (NBP) of managed temperate grasslands (37 ± 30 gC m−2 yr−1 (P < 0.01) over the 11 sites) because the management module contains provisions to simulate the carbon fluxes of forage yield, herbage consumption, animal respiration and methane emissions.
35
Adamo, Maria, Valeria Tomaselli, Cristina Tarantino, Saverio Vicario, Giuseppe Veronico, Richard Lucas, and Palma Blonda. "Knowledge-Based Classification of Grassland Ecosystem Based on Multi-Temporal WorldView-2 Data and FAO-LCCS Taxonomy." Remote Sensing 12, no. 9 (May 3, 2020): 1447. http://dx.doi.org/10.3390/rs12091447.
Full textAbstract:
Grassland ecosystems can provide a variety of services for humans, such as carbon storage, food production, crop pollination and pest regulation. However, grasslands are today one of the most endangered ecosystems due to land use change, agricultural intensification, land abandonment as well as climate change. The present study explores the performance of a knowledge-driven GEOgraphic-Object—based Image Analysis (GEOBIA) learning scheme to classify Very High Resolution (VHR) images for natural grassland ecosystem mapping. The classification was applied to a Natura 2000 protected area in Southern Italy. The Food and Agricultural Organization Land Cover Classification System (FAO-LCCS) hierarchical scheme was instantiated in the learning phase of the algorithm. Four multi-temporal WorldView-2 (WV-2) images were classified by combining plant phenology and agricultural practices rules with prior-image spectral knowledge. Drawing on this knowledge, spectral bands and entropy features from one single date (Post Peak of Biomass) were firstly used for multiple-scale image segmentation into Small Objects (SO) and Large Objects (LO). Thereafter, SO were labelled by considering spectral and context-sensitive features from the whole multi-seasonal data set available together with ancillary data. Lastly, the labelled SO were overlaid to LO segments and, in turn, the latter were labelled by adopting FAO-LCCS criteria about the SOs presence dominance in each LO. Ground reference samples were used only for validating the SO and LO output maps. The knowledge driven GEOBIA classifier for SO classification obtained an OA value of 97.35% with an error of 0.04. For LO classification the value was 75.09% with an error of 0.70. At SO scale, grasslands ecosystem was classified with 92.6%, 99.9% and 96.1% of User’s, Producer’s Accuracy and F1-score, respectively. The findings reported indicate that the knowledge-driven approach not only can be applied for (semi)natural grasslands ecosystem mapping in vast and not accessible areas but can also reduce the costs of ground truth data acquisition. The approach used may provide different level of details (small and large objects in the scene) but also indicates how to design and validate local conservation policies.
36
Zangaro, Waldemar, Adrielly Pereira Ansanelo, Luis Eduardo Azevedo Marques Lescano, Ricardo de Almeida Alves, Artur Berbel Lírio Rondina, and Marco Antonio Nogueira. "Infection intensity, spore density and inoculum potential of arbuscular mycorrhizal fungi decrease during secondary succession in tropical Brazilian ecosystems." Journal of Tropical Ecology 28, no. 5 (August 29, 2012): 453–62. http://dx.doi.org/10.1017/s0266467412000399.
Full textAbstract:
Abstract:Little is known about the relationship involving arbuscular mycorrhizal (AM) fungi and functional groups of plants that characterize different phases of tropical succession. We appraised the AM infection intensity of root cortex and spore density in the soil in sites over tropical successional gradients (grassland, secondary forest and mature forest) for several years in Araucaria, Atlantic and Pantanal ecosystems in Brazil. The intensity of AM infection decreased with advancing successional stages in all ecosystems and it was around 60–80% in early stages of succession, 37–56% in secondary forests and 19–29% in mature forests. Similarly, the AM spore number also decreased with advancing succession and was the highest in early stages (73–123 g−1), intermediate in secondary forests (32–54 g−1) and lowest in the mature forests (10–23 g−1). To verify whether such reductions influenced the potential of AM inoculum in soil, seedlings of Heliocarpus popayanensis (Malvaceae) were grown as test plants in soils obtained from five grasslands, five young secondary forests, and five mature forests in the Atlantic ecosystem. The soil inocula from the grasslands and secondary forests were 7.6 and 5.7 times more effective in stimulating seedling growth than inocula from the mature forests, respectively. Our results show that plant species in grasslands and young secondary forests stimulate the multiplication of AM fungi, leading to a higher potential of the AM inoculum. In later-successional stages, plant investment in AM fungi decreases and the potential of the AM inoculum is also reduced.
37
Merbold, L., J. Ardö, A. Arneth, R. J. Scholes, Y. Nouvellon, A. de Grandcourt, S. Archibald, et al. "Precipitation as driver of carbon fluxes in 11 African ecosystems." Biogeosciences Discussions 5, no. 5 (October 27, 2008): 4071–105. http://dx.doi.org/10.5194/bgd-5-4071-2008.
Full textAbstract:
Abstract. This study reports carbon and water fluxes between the land surface and atmosphere in eleven different ecosystems types in Sub-Saharan Africa, as measured using eddy covariance (EC) technology in the first two years of the CarboAfrica network operation. The ecosystems for which data were available ranged in mean annual rainfall from 320 mm (Sudan) to 1150 mm (The Republic of Congo) and include a spectrum of vegetation types (or land cover) (open savannas, woodlands, croplands and grasslands). Given the shortness of the record, the EC data were analysed across the network rather than longitudinally at sites, in order to understand the driving factors for ecosystem respiration and carbon assimilation, and to reveal the different water use strategies in these highly seasonal environments. Values for maximum net carbon assimilation rates (photosynthesis) ranged from 12 μmol CO2 m−2 s−1 in a dry, open Acacia savanna (C3-plants) up to 40 μmol CO2 m−2 s−1 for a tropical moist grassland. Maximum carbon assimilation rates were highly correlated with mean annual rainfall (R2=0.89). Maximum photosynthetic uptake rates were positively related to satellite-derived fAPAR. Ecosystem respiration was dependent on temperature at all sites, and was additionally dependent on soil water content at sites receiving less than 1000 mm of rain per year. All included ecosystems, except the Congolese grassland, showed a strong decrease in 30-min assimilation rates with increasing water vapour pressure deficit above 2.0 kPa.
38
Huang, Xiaotao, Li Ma, Geping Luo, Chunbo Chen, Gangyong Li, Yang Yan, Huakun Zhou, Buqing Yao, and Zhen Ma. "Human appropriation of net primary production estimates in the Xinjiang grasslands." PLOS ONE 15, no. 12 (December 2, 2020): e0242478. http://dx.doi.org/10.1371/journal.pone.0242478.
Full textAbstract:
The human appropriation of net primary production (HANPP) was developed to estimate the intensity of human activities in natural ecosystems, which is still unclear in the Xinjiang grasslands. Using the Biome-Biogeochemical Cycle (Biome-BGC) grazing model in combination with field data, we assessed the HANPP and explored its spatiotemporal patterns in the Xinjiang grasslands. Our results showed that (1) the HANPP increased from 38 g C/m2/yr in 1979 to 88 g C/m2/yr in 2012, with an average annual increase of 1.47%. The HANPP was 80 g C/m2/yr, which represented 51% of the potential net primary production (NPPpot), and the HANPP efficiency was 70% in this region. (2) The areas with high HANPP values mainly occurred in northern Xinjiang and northwest of the Tianshan Mountains, while areas with low HANPP values mainly occurred in southern Xinjiang and southwest of the Tianshan Mountains. (3) Interannual variations in HANPP and NPPpot were significantly positively correlated (P<0.01). Interannual variations in HANPP efficiency and grazing intensity were negatively correlated (P<0.01). These results can help identify the complex impacts of human activities on grassland ecosystems and provide basic data for grassland management.
39
Foreman, Paul W. "A framework for testing the influence of Aboriginal burning on grassy ecosystems in lowland, mesic south–eastern Australia." Australian Journal of Botany 64, no. 8 (2016): 626. http://dx.doi.org/10.1071/bt16081.
Full textAbstract:
The complex interactions among climate, soils, fire and humans in the biogeography of natural grasslands has long been debated in Australia. On the one hand, ecological models assume the primacy of climate and soils. On the other, Aboriginal burning is hypothesised to have altered the entire continent since before the last glacial maximum. The present paper develops a framework to test for the ‘fingerprint’ of Aboriginal burning in lowland, mesic grassy ecosystems of south-eastern Australia, using ecological theory, and the ethno-historical record. It is clear that fire-stick farming was used to promote staple roots in south-eastern Australia and, in some instances, it has been shown to influence grassland–woodland boundaries. The framework comprises the following three evidence lines: (1) archival benchmarking and palaeoecology; (2) phytoecology; and (3) ethnology and archaeology. That fire-stick farming was likely instrumental in grassland formation and maintenance must be supported by evidence that shows that ‘natural’ grasslands exist in climatically–edaphically unexpected places, that fine-scale patterns and dynamics are at least partly due to fire and that the fire regime has been influenced by Aboriginal burning. Application of the framework indicated that widespread Aboriginal burning for staple foods likely extended the area of temperate grasslands and influenced their structure and function.
40
Good, Megan K., Jodi N. Price, Peter Clarke, and Nick Reid. "Densely regenerating coolibah (Eucalyptus coolabah) woodlands are more species-rich than surrounding derived grasslands in floodplains of eastern Australia." Australian Journal of Botany 59, no. 5 (2011): 468. http://dx.doi.org/10.1071/bt11079.
Full textAbstract:
Woody plant encroachment – the conversion of grasslands to tree- or shrub-dominated ecosystems – occurs in rangelands and savannas worldwide. In eastern Australia, coolibah (Eucalyptus coolabah subsp. coolabah Blakely & Jacobs) regenerated densely following floods in the mid 1970s, converting derived grasslands to dense woodlands. We compared soil and groundstorey vegetation attributes of dense coolibah regeneration to adjacent derived grasslands at three grazed sites in the northern riverine plains of New South Wales. Groundstorey species richness and diversity were significantly higher and groundstorey biomass was significantly lower in dense regeneration plots than in derived grassland plots. Soils from dense regeneration had higher C : N and pH, and lower Na than soils from derived grasslands. Although groundstorey species composition differed significantly between derived grasslands and dense regeneration within sites, variation among sites was more pronounced, indicating that site factors influence community composition more than dense regeneration of coolibah. Our findings suggest that, in contrast to other studies of woody plant encroachment, dense regeneration of coolibah does not result in a decrease in plant biodiversity or soil condition.
41
Zhao, Jingxue, Tongren Xu, Jingfeng Xiao, Shaomin Liu, Kebiao Mao, Lisheng Song, Yunjun Yao, Xinlei He, and Huaize Feng. "Responses of Water Use Efficiency to Drought in Southwest China." Remote Sensing 12, no. 1 (January 6, 2020): 199. http://dx.doi.org/10.3390/rs12010199.
Full textAbstract:
Water use efficiency (WUE) measures the tradeoff between carbon uptake and water consumption in terrestrial ecosystems. It remains unclear how the responses of WUE to drought vary with drought severity. We assessed the spatio-temporal variations of ecosystem WUE and its responses to drought for terrestrial ecosystems in Southwest China over the period 2000–2017. The annual WUE values varied with vegetation type in the region: Forests (3.25 gC kg−1H2O) > shrublands (2.00 gC kg−1H2O) > croplands (1.76 gC kg−1H2O) > grasslands (1.04 gC kg−1H2O). During the period 2000–2017, frequent droughts occurred in Southwest China, and overall, drought had an enhancement effect on WUE. However, the effects of drought on WUE varied with vegetation type and drought severity. Croplands were the most sensitive to drought, and slight water deficiency led to the decline of cropland WUE. Over grasslands, mild drought increased its WUE while moderate and severe drought reduced its WUE. For forests and shrublands, mild and moderate drought increased their WUE, and only severe drought reduce their WUE, indicating that these ecosystems had stronger resistance to drought. Assessing the patterns and trends of ecosystem WUE and its responses to drought are essential for understanding plant water use strategy and informing ecosystem water management.
42
Robin, Vincent, Oliver Nelle, Brigitte Talon, Peter Poschlod, Dominique Schwartz, Marie-Claude Bal, Philippe Allée, Jean-Louis Vernet, and Thierry Dutoit. "A comparative review of soil charcoal data: Spatiotemporal patterns of origin and long-term dynamics of Western European nutrient-poor grasslands." Holocene 28, no. 8 (May 8, 2018): 1313–24. http://dx.doi.org/10.1177/0959683618771496.
Full textAbstract:
The nutrient-poor grasslands of Western Europe are of major conservation concern because land use changes threaten their high biodiversity. Studies assessing their characteristics show that their past and on-going dynamics are strongly related to human activities. Yet, the initial development patterns of this specific ecosystem remain unclear. Here, we examine findings from previous paleoecological investigations performed at local level on European grassland areas ranging from several hundred square meters to several square kilometers. Comparing data from these locally relevant studies at a regional scale, we investigate these grasslands’ spatiotemporal patterns of origin and long-term dynamics. The study is based on taxonomic identification and radiocarbon AMS dating of charcoal pieces from soil/soil sediment archives of nutrient-poor grasslands in Mediterranean and temperate Western Europe (La Crau plain, Mont Lozère, Grands Causses, Vosges Mountains, Franconian Alb, and Upper-Normandy region). We address the following questions: (1) What are the key determinants of the establishment of these nutrient-poor grasslands? (2) What temporal synchronicities might there be? and (3) What is the spatial scale of these grasslands’ past dynamics? The nutrient-poor grasslands in temperate Western Europe are found to result from the first anthropogenic woodland clearings during the late Neolithic, revealed by fire events in mesophilious mature forests. In contrast, the sites with Mediterranean affinities appear to have developed at earlier plant successional stages (pine forest, matorral), established before the first human impacts in the same period. However, no general pattern of establishment and dynamics of the nutrient-poor grasslands could be identified. Local mechanisms appear to be the key determinants of the dynamics of these ecosystems. Nevertheless, this paleoecological synthesis provides insights into past climate or human impacts on present-day vegetation.
43
Feurdean, Angelica, Eszter Ruprecht, Zsolt Molnár, Simon M. Hutchinson, and Thomas Hickler. "Biodiversity-rich European grasslands: Ancient, forgotten ecosystems." Biological Conservation 228 (December 2018): 224–32. http://dx.doi.org/10.1016/j.biocon.2018.09.022.
Full text
44
Sun, Z. G., X. H. Long, C. M. Sun, W. Zhou, W. M. Ju, and J. L. Li. "Evaluation of net primary productivity and its spatial and temporal patterns in southern China’s grasslands." Rangeland Journal 35, no. 3 (2013): 331. http://dx.doi.org/10.1071/rj12061.
Full textAbstract:
The net primary productivity (NPP) of grassland ecosystems is an important indicator of the capacity for carbon (C) absorption. The Global Production Efficiency Model was adopted to simulate NPP in southern China’s grasslands and to analyse the temporal and spatial dynamics from 1981 to 2000. There was a high correlation between measured and simulated values (R2 = 0.84). Based on the data from 1981 to 2000, the mean annual NPP was 1082 g C m–2 year–1, and the highest value (1798 g C m–2 year–1) was in Hainan province, and the lowest value (500 g C m–2 year–1) was in south-western Tibet. The highest mean NPP values were in the permanent wetlands (1193 g C m–2 year–1) and savannas (1137 g C m–2 year–1); woody savannas had an intermediate value (1087 g C m–2 year–1), and the lowest NPP occurred in typical grasslands and open shrubs, the mean values were 709 and 689 g C m–2 year–1, respectively. Temporally, the total NPP in southern China’s grasslands slightly increased in the 20-year period, especially from 1981 to 1990. The mean annual total of NPP in the 20 years was 0.758 Pg C. Inter-annual variation in total NPP was driven mainly by mean annual temperature rather than mean annual precipitation. The results suggest that grassland ecosystems in southern China have a large C sink.
45
Bhandari, Jyoti, Xuebiao Pan, and G. C. Dhruba Bijaya. "Spatial and Seasonal Variation in Rain Use Efficiency in Semiarid Grasslands of Inner Mongolia." Advances in Meteorology 2015 (2015): 1–7. http://dx.doi.org/10.1155/2015/917415.
Full textAbstract:
Rain use efficiency (RUE) is an important indicator for identifying the response of plant production to variation in precipitation patterns, especially in semiarid ecosystem grasslands of Inner Mongolia. We have investigated the response and spatial patterns of RUE to precipitation patterns based on five years (2006, 2007, 2008, 2012, and 2013) of records from semiarid ecosystem sites across Inner Mongolia. Our results showed thatRUEADMwas lowest in the wettest year (2012) and highest in the year following the driest year (2008). There was no significant correlation betweenRUEADMandRUETDMin typical and desert steppe.RUETDMwas strongly correlated with both annual precipitation (AP) and growing season precipitation (GSP) compared toRUEADM.RUEADM, therefore, cannot be used in place ofRUETDM.RUEADMincreased with species richness. The relationship betweenRUEADMand species richness was significantly correlated in meadow steppe, typical steppe, and desert steppe. Our findings can shed light on the spatial utilization pattern of seasonal rainfall in semiarid grassland ecosystems.
46
Sun, Xiaofang, Meng Wang, Guicai Li, Junbang Wang, and Zemeng Fan. "Divergent Sensitivities of Spaceborne Solar-Induced Chlorophyll Fluorescence to Drought among Different Seasons and Regions." ISPRS International Journal of Geo-Information 9, no. 9 (September 9, 2020): 542. http://dx.doi.org/10.3390/ijgi9090542.
Full textAbstract:
As a newly emerging satellite form of data, solar-induced chlorophyll fluorescence (SIF) provides a direct measurement of photosynthetic activity. The potential of SIF for drought assessment in different grassland ecosystems is not yet clear. In this study, the correlations between spaceborne SIF and nine drought indices were evaluated. Standardized precipitation evapotranspiration index (SPEI) at a 1, 3, 6, 9, 12 month scale, Palmer drought severity index (PDSI), soil moisture, temperature condition index (TCI), and vapor pressure deficit (VPD) were evaluated. The relationships between different grassland types and different seasons were compared, and the driving forces affecting the sensitivity of SIF to drought were explored. We found that the correlations between SIF and drought indices were different for temperate grasslands and alpine grasslands. The correlation coefficients between SIF and soil moisture were the highest (the mean value was 0.72 for temperate grasslands and 0.69 for alpine grasslands), followed by SPEI and PDSI at a three month scale, and the correlation coefficient between SIF and TCI was the lowest (the mean value was 0.38 for both temperate and alpine grasslands). Spaceborne SIF is more effective for drought monitoring during the peak period of the growing season (July and August). Temperature and radiation are important factors affecting the sensitivity of SIF to drought. The results from this study demonstrated the importance of SIF in drought monitoring especially for temperate grasslands in the peak growing season.
47
DAHLSTRÖM, ANNA, ANA-MARIA IUGA, and TOMMY LENNARTSSON. "Managing biodiversity rich hay meadows in the EU: a comparison of Swedish and Romanian grasslands." Environmental Conservation 40, no. 2 (February 28, 2013): 194–205. http://dx.doi.org/10.1017/s0376892912000458.
Full textAbstract:
SUMMARYSemi-natural hay meadows are among the most biodiversity-rich terrestrial ecosystems, and are managed for conservation purposes in most of Europe, including Sweden. Romania has some of Europe's largest areas of grasslands still managed with traditional methods. Through interviews and field studies, current management practices were investigated in two Romanian villages, and compared with CAP-generated grassland management in Swedish hay meadows and historical Swedish management of grasslands. The study evaluated the effect of the eligibility criteria within both countries’ National Rural Development Programmes (NRDPs) on different ecologically important components of hay meadow management. The success of Swedish management was measured by assessing population trends for 25 grassland plant species. Current management proved to be considerably more diverse in Romania than in Sweden, but historical Swedish management was similar to management in Romania. Both countries’ NRDPs provide support for some management components, but create barriers against other components. The Romanian NRDP contained more barriers than the Swedish NRDP, yet Swedish management showed little success in preserving grassland plants. NRDPs should nourish the use of local and traditional knowledge in order to preserve biodiversity in semi-natural grasslands. There are major limitations in both countries’ NRDPs.
48
Bürgés, György. "Pest-fauna of grasslands and seed-grass varieties." Acta Agraria Debreceniensis, no. 62 (November 2, 2014): 56–59. http://dx.doi.org/10.34101/actaagrar/62/2166.
Full textAbstract:
The present paper deals with various herbivorous species living in grassland ecosystems. The research focused not only on the complexity of pests in grasslands but also on individual pest species; their biology and the severity of damage, with special regard to seed feeders of some frequent herd’s grass species. The observed pests are showed in two ways, both taxonomically and according to their localization on the crop that is where they cause damage. An attempt was made to present the results being easily understandable for practitioners.
49
Dröse, William, Luciana Regina Podgaiski, Adriano Cavalleri, Rodrigo Machado Feitosa, and Milton Mendonça Jr. "Ground-Dwelling and Vegetation Ant Fauna in Southern Brazilian Grasslands." Sociobiology 64, no. 4 (December 27, 2017): 381. http://dx.doi.org/10.13102/sociobiology.v64i4.1795.
Full textAbstract:
Non-forest ecosystems, as natural grasslands from Southern Brazil, are still neglected in conservation policies. Measuring their biodiversity is one of the main steps to generate management strategies for these habitats. This study aims to (i) describe grassland ant richness and composition in Rio Grande do Sul state, and (ii) compare ant communities sampled on the ground and in grassland vegetation, adding to our knowledge of habitat use patterns and vegetation associated species. Six sites were sampled, three belonging to the Pampa biome and three in highland region from the Atlantic Forest biome. Ant fauna was collected once per year in summer during four years in each site with pitfalls traps and sweeping nets. Overall, 29,812 ant individuals were sampled belonging to eight subfamilies, 30 genera e 106 species. The grasslands of Pampa accumulated 91 species and 45 exclusive species, while highland grasslands summed up 61 species and only 15 exclusive species. Species composition differs between biomes as well as between sampling methods. Ant communities sampled from vegetation represented a clear subset of the fauna sampled with pitfall traps, and indication analysis showed only two species associated with this stratum: Myrmelachista gallicola and Pseudomyrmex nr. flavidulus. This study highlights the importance of Southern Brazilian grasslands and the need for specific conservation strategies for the natural grasslands from each biome.
50
KEMP, D. R., and D. L. MICHALK. "Towards sustainable grassland and livestock management." Journal of Agricultural Science 145, no. 6 (July 12, 2007): 543–64. http://dx.doi.org/10.1017/s0021859607007253.
Full textAbstract:
SUMMARYGrasslands are one of the world's major ecosystems groups and over the last century their use has changed from being volunteer leys, or a resource on non-arable land, to a productive resource equal to any crop and managed as such. Many grasslands are now being acknowledged as having a multifunctional role in producing food and rehabilitating crop lands, in environmental management and cultural heritage. However, grasslands across the globe are under increasing pressure from increasing human populations, reduced areas with increasing livestock numbers, and declining terms of trade for livestock production, and they are managed to varying degrees of effectiveness. The complexity of grassland uses and the many aspects of grassy ecosystems require a framework wherein solutions for better management can be developed. The present paper discusses a generic approach to grassland management to satisfy these multiple objectives. A focus on ecosystem functionality, i.e. on water, nutrient and energy cycling and on the biodiversity required to sustain those functions, provides a means of resolving the dilemmas faced, through the intermediary, management-related, criteria of herbage mass, which also relates directly to animal production. Emphasis is placed on the opportunities to satisfy multiple objectives. A consideration of the basic relationships between stocking rate and animal production shows that the longer-term, economically optimal stocking rate is associated with improved environmental outcomes. There may be environmental objectives that go beyond economically sustainable limits for livestock producers and in those cases direct payments from the government or others will be needed. These are likely to be where degradation is clearly apparent. The achievement of desirable outcomes in grassland management that satisfy multiple objectives will require new areas of research that seek viable solutions for farmers and society.