Vertical seed distribution in the soil constrains regeneration of Bromus pictus in a Patagonian steppe

Question: What is the effect of vertical seed distribution (i.e. seeds on soil surface or buried) and the relative importance of vertical and horizontal seed distribution (i.e. seeds near established vegetation or near bare soil) for seedling emergence? Location: Patagonian arid steppe. Methods: To evaluate the effect of vertical seed distribution on seedling emergence, four sowing treatments were used in field and greenhouse experiments. Vertical vs. horizontal seed distribution and the occurrence of seedlings were analysed in the field. Effects of trampling and mechanical drilling on seedling emergence were investigated experimentally in the field. Results: In field and glasshouse experiments buried seeds showed a higher emergence and larger seedling size than seeds lying on the soil surface. The observational field study indicated that natural emergence was not associated with particular microsites or plant cover (horizontal distribution), but that most seedlings emerged from buried positions (vertical distribution). Buried seeds represented less than 10% of the sampled seed cohort but account for almost 60% of the seedlings. The trampling/drilling experiment showed that sheep trampling and mechanical drilling increased seedling emergence compared to non‐treated controls. Conclusions: The population dynamics of Bromus pictus is strongly constrained by the vertical position of seeds, which largely affects emergence, and seed horizontal distribution, which largely affects seedling survival. Our results showed that sheep trampling after seed dispersal may be a low‐input technique for increasing grass recruitment.     

Seed bed treatment effects on vegetation and seedling establishment in a New Zealand pasture one year after seeding with native woody species

Summary Efforts to re‐establish indigenous forests in pastoral New Zealand have increased as the value of native biodiversity has been realized. Direct seeding of woody species is preferable to transplanting, as labour and material costs are less. However, the success rate of direct seeding in pasture has been variable due to intense competition from adventive species. We initiated an experiment in pasture plots adjacent to a forest fragment where seed bed treatments (increasing in degree of disturbance from herbicide application to turf removal and topsoil removal) in combination with mulch treatments (wood chip shavings with and without forest floor organic material) were seeded with a mixture of New Zealand lowland forest species. The objective of the study was to determine if early successional plant communities, and ultimately seedling establishment, differed as a result of seed bed preparation after 1 year. Coprosma robusta (Karamu) and Kunzea ericoides (Kanuka) seedlings established on plots in significant numbers: both species were most abundant on topsoil‐removed plots where bare substrate was greatest and plant cover least. Both seed bed treatments and mulching treatments led to measurable differences in overall composition of early successional plant communities. However, absence of plant cover and low soil fertility (both associated with the topsoil‐removed treatment) were the most important factors in seedling success.     

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

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

Disturbance of suburban Fagus forests by recreational activities: Effects on soil characteristics,above‐ground vegetation and seed bank

Questions: How does recreational disturbance (human trampling) affect soil characteristics, the performance of the understorey vegetation, and the density and species composition of the soil seed bank in Fagus sylvatica forests? Location: Suburban forests near Basel, northwestern Switzerland. Methods: We compared various soil characteristics and the performance of the understorey vegetation in six beech forest areas frequently disturbed by recreational activities with those in six undisturbed control areas, in spring 2003. In the same forest areas, the soil seed bank was investigated using the seedling emergence method. Samples were obtained from soil cores in January 2003. Results: We found substantial changes in soil compaction, above‐ground vegetation and in the soil seed bank due to recreational activities. In frequently visited areas, soil compaction was enhanced which caused a decrease in cover, height and species richness of both herb and shrub layers. Compared with control areas, the number of trampling‐tolerant species of the seed bank was significantly higher in disturbed areas, and total species richness tended to be higher in disturbed than in control areas. Furthermore, the similarity in species composition between the above‐ground vegetation and seed bank was significant lower in disturbed than in control areas. Conclusions: The intensive use of suburban forests for recreational activities, mainly picnicking, affects the vegetation of natural beech forests. Our study indicates that a restoration of degraded forest areas from the soil seed bank would result in a substantial change of the vegetation composition.     

Hydrocarbon Tolerance Correlates with Seed Mass and Relative Growth Rate

The abundance and vegetation cover of plant species with different seed masses growing on crude oil contaminated and uncontaminated field plots were examined. In addition, seedling mass and relative growth rate of eight plants in four seed mass classes were compared in contaminated and uncontaminated soils. Species producing seed in the second largest seed class (1.0 to 9.9 mg) were more common on contaminated than uncontaminated field plots. Species with seed in the smallest seed class (< 0.1 mg) were less common on contaminated than uncontaminated plots. Species with seed masses between 1.0 and 9.9 mg formed 15% more vegetation cover, and those with masses between 0.1 and 0.9 mg formed nearly 15% less vegetation cover on contaminated compared to uncontaminated field plots. In the growth chamber, species with larger seeds produced approximately 25% less seedling mass and exhibited a 32% reduction in relative growth rate, when grown in contaminated compared to uncontaminated soil. Small-seeded species had reductions of 95% in seedling mass and 72% in relative growth rate. Species with the highest relative growth rates in uncontaminated soil had the lowest seedling mass in contaminated soil. Seed mass and relative growth rate were negatively correlated (r = 0.866).     

Fire as a control agent of demographic structure and plant performance of a rare Mediterranean endemic geophyte

We examine the effects of fire and/or surrounding vegetation cover on demographic stage densities and plant performance for a rare endemic geophyte, Acis nicaeensis (Alliaceae), in Mediterranean xerophytic grasslands of the 'Alpes-Maritimes' French 'département', through sampling plots in unburned and burned treatments. Fire increases density of flowering individuals and seedling emergence, as well as clump densities and number of individuals per clump, per limiting vegetation height and cover, and increasing bare soil cover. In contrast, fire has no effect on reproductive success. Nevertheless, two growing seasons after fire, all parameters of demographic stages and plant performance do not significantly differ between the two treatments. Small-scale fire is beneficial for the regeneration of this threatened geophyte at a short-time scale. In this context, a conservation planning with small and controlled fires could maintain the regeneration window for populations of rare Mediterranean geophytes.     

Effects of experimental and real land use on seedling recruitment of six fen species

Seedling emergence and early establishment of six fen species differing in seed mass and growth form were investigated under experimental land use with changed vegetation structure and under real land use in a calcareous fen. Seeds of all six species were sown in plots with different experimental land-use treatments: summer and autumn mowing with or without litter removal, trampling and abandonment. Additionally, emergence and survival of experimentally sown seeds was investigated under real land use on adjacent sites managed by mowing, grazing, intense trampling or abandonment.On abandoned plots and on plots without litter removal of the land-use experiment, emergence rates of all species were negatively affected either by high litter and moss cover or by tall canopy. No differences were found between autumn and summer mowing. Gap creation by experimental trampling did not increase germination rate. Under real land use, establishment of seedlings of most species was positively affected by litter cover and tall canopy. Trampling, in contrast, had a severe negative effect on seedling survival.The investigated species differed in their germination ability which was tested in the germination chamber and in their response to land use. Succisa pratensis with the highest seed mass germinated well in the chamber and in the field more or less regardless of land use. The low germination rate of Parnassia palustris in the germination chamber indicated a limitation of viable seeds. In the field, however, seedling emergence was additionally limited by microsite availability. Seeds of Serratula tinctoria and Primula farinosa germinated well in the germination chamber, but seedling recruitment in the field was hampered in the presence of a high litter or moss cover. Seeds of Tofieldia calyculata and Pinguicula vulgaris were strongly dependent on the availability of suitable microsites in the field. They hardly germinated under natural conditions, in spite of a high number of germinable seeds in the germination chamber.     

Creosotebush vegetation after 50 years of lagomorph exclusion

In 1939, an experiment was established on the Jornada Experimental Range to evaluate the effects of shrub removal, rabbit exclusion, furrowing, and seeding in creosotebush [Larrea tridentata (DC.) Cov] vegetation. Sixteen plots (21.3×21.3 m) were laid out in four rows of four plots per row with a buffer zone of 7.6 m between plots and rows. A barbed wire fence excluded cattle and poultry wire fencing excluded lagomorphs. Treatments were factorially applied at two levels. Plant cover in the plots was sampled in 1938 (before treatment), 1947, 1956, 1960, 1967 and 1989 with randomly located, line-intercept transects. Data from all sampling dates were analyzed as a split plot in time and main effects for 1989 tested by analysis of variance for a 2×4 factorial experiment. There were significant (P<0.10) year x treatment interactions. Seeding and furrowing treatments were ineffective but lagomorph exclusion and shrub clearing treatments resulted in significant treatment differences for several species. In 1989, basal area of spike dropseed (Sporobolus contractus A.S. Hitchc.) was 30-fold greater on the lagomorph excluded than on the lagomorph unexcluded treatment. Canopy cover of honey mesquite (Prosopis glandulosa Torr. var. glandulosa), tarbush (Flourensia cernua DC.) and mariola (Parthenium incanum H.B.K.) were affected by lagomorph exclusion. None of the responses were viewed as successional in nature. They principally represented individual species sensitivities to either absence of a primary herbivore or removal of aboveground shrub biomass. Though the physical treatments could be regarded as relatively severe disturbances of the system, the impacts on community vegetation dynamics were relatively insignificant.     

Rapid recovery of recently overexploited winter grazing pastures for reindeer in northern Norway

During the last 25 yr, Sami reindeer husbandry in parts of Finnmarksvidda in the Norwegian Arctic has been in a critical state because of overexploitation of lichen-dominated tundra, which serves as winter forage. To better understand the ecosystem’s capabilities for recovery we investigated vegetation cover changes over a 7-yr period, starting in 1998, at 52 sites dispersed over a large area at Finnmarksvidda. Two types of plots were established: one fenced from reindeer grazing and trampling and one open for reindeer. The investigations in 2005 showed that lichen cover had had a significant and rapid increase (up to 8.6-fold per year). The cover of vascular plants, mainly dwarf shrubs, also increased significantly, while barren areas and the cover of litter decreased significantly during the period. Mean relative growth rate of lichen biomass was 0.083 ± 0.011 per year in open plots, which is considered very rapid recovery compared to previous studies. Lichen recovery was significantly faster on leeward ridges than on exposed ridges, and fencing alone did not have any significant effects on lichen recovery, but in interaction with time, fencing contributed to increasing recovery rates. The lichen heath recovery was reciprocally correlated with reindeer density. In addition, lichen recovery was probably facilitated by recent climate changes, viz. shallower snow depths which made leeward tundra and forest floor vegetation accessible for reindeer, and increased summer precipitation rates which improved growth rates. The results from this study show that in a very short time there was a transition from an overexploited depauperate vegetation and barren ground state to a flourishing lichen-dominated vegetation state, suggesting that the injuries were repairable. The vegetation transitions which have taken place in the study area are considered to be reversible with fewer persistent effects.     

The effects of habitat edges and trampling on understorey vegetation in urban forests in Helsinki,Finland

Question: How do habitat edges and trampling affect mesic (Myrtillus type) understorey vegetation in fragmented urban forests, and what are the relative strengths and spatial extent of these effects? Location: The city of Helsinki, southern Finland. Methods: Vegetation sample plots were placed at different distances from the forest edge. At each distance we selected plots on, next to and away from paths of different levels of wear, and the covers and frequencies of plant species were sampled. We used generalized linear mixed models and ordination techniques to test our hypotheses. Results: The effect of the edge penetrated up to 50 m into the forest interior. Only light effects of trampling were found in seemingly untrampled areas, in addition to the direct effects of trampling on the paths. Both trampling and edge effects changed the forest understorey species composition. Trampling changed plant species composition locally on paths, and provided opportunities for new species to establish in previously unbroken forest vegetation. Urban forest edges were characterised by species better adapted to sunny, warm and dry conditions. These species, such as grasses, replaced more sensitive forest species, such as dwarf shrubs and mosses. We observed a large number of light demanding deciduous trees at the edges, which may be one of the factors increasing soil fertility and consequently promoting the high abundance of fast growing species, such as grasses and herbs related to more fertile site types. Conclusions: We recommend that urban forest fragments left within urban development should be at least 2–3 ha in size and that the shape of the patch and the number of potential recreational users should be taken into account when preserving true forest understorey vegetation from the effects of edges and trampling.     

The role of the seed bank,seed rain and the timing of disturbance in gap regeneration

Abstract. Question: Does the degree and timing of disturbance contribute significantly to the pattern and process of regeneration in plant communities as a consequence of the availability and number of species of propagules present? Location: Acid grassland at 230 m a.s.l., eastern Scotland, UK. Methods : Plots were surface disturbed or had their soil profile inverted at monthly intervals at 12 dates during a year. Seed bank and seed rain were assessed at each treatment time. The effect of disturbance intensity and timing on the regenerating vegetation was assessed. Results: Removing the seed bank significantly slowed regeneration, as it contributed 43 % of developing cover after one year where it was present. At an individual seed level, seed in the seed rain had a much higher likelihood of contributing to the regenerating vegetation than a seed in the seed bank. Some species showed a reliance on the seed bank for regeneration, and hence there was a significant difference in the vegetation that developed between plots with the seed bank intact and those where it was removed. Winter disturbed plots (little seed rain) had slower rates of re‐vegetation than summer disturbed plots. Timing had little effect on species composition, though a significantly higher cover of perennial forb species developed on the winter disturbed plots. Conclusion: Removing the contribution of the seed bank had a greater effect on the composition of regenerating vegetation than the effect of seasonal variation on the seed rain.     

Disturbance of forest by trampling: Effects on mycorrhizal roots of seedlings and mature trees of Fagus sylvatica

The effects of disturbance by recreational activities (trampling) on changes in soil organic matter (SOM) and on mycorrhizal roots of seedlings and mature trees were studied in four stands of a beech (Fagus sylvatica L.) forest near Basel, Switzerland. At each site, comparable disturbed and undisturbed plots were selected. Disturbance reduced ground cover vegetation and leaf litter. Beech seedlings had lower biomass after disturbance. Ergosterol concentration in seedling roots, an indicator of mycorrhizal fungi, was lower in two of the four disturbed plots compared to undisturbed plots; these two disturbed sites had especially low litter levels. Based on ergosterol measurements, mycorrhizas of mature trees did not appear to be negatively affected by trampling. Total fine roots and SOM were higher in the disturbed than in the undisturbed plots at three sites. At the fourth site, fine roots and SOM in the disturbed areas were lower than in the undisturbed areas most probably due to nutrient input following picnic activities. Principal component analysis revealed a close correlation between SOM and fine roots of mature trees as well as litter and seedling biomass. Trampling due to recreational activities caused considerable damage to the vegetation layer and in particular to the beech seedlings and their mycorrhizal fine roots, whereas, roots of mature trees were apparently resilient to trampling.     

Residual herbicide treatments reduce Andropogon gayanus (Gamba Grass) recruitment for mine site restoration in northern Australia

Weed invasion is a major threat to Australian tropical savannas, and controlling weeds is essential for successful re‐establishment of native species on disturbed sites. Gamba Grass (Andropogon gayanus) is an African grass which has invaded large areas of tropical savanna across northern Australia. Current management strategies in northern Australia focus on fire and glyphosate to effectively control mature plants; however, re‐establishment of infestations from the soil seed bank remains a major challenge to eradication efforts. This study focused on the effects of soil seed bank treatments on Gamba Grass recruitment on a mine site in northern Australia. Adult Gamba Grass plants within test plots were killed with glyphosate to exclude resource competition. Chemical, physical and biological treatments were then applied, and the treatment effects on subsequent Gamba Grass seedling emergence and survival quantified. Seedling emergence was significantly reduced by three of the four residual herbicide treatments tested. The most effective herbicide treatments, dalapon and sulfometuron, reduced emergence by 90% compared to the standard glyphosate treatment alone. This equated to a reduction in Gamba Grass seedling emergence from 1 seedling/m² to 1 seedling 10 m^?2, a major improvement for Gamba Grass management. These residual herbicide treatments significantly reduced the population density of Gamba Grass for at least 5 months after emergence. The physical and biological treatments did not have a significant effect on seedling emergence. This significant reduction in Gamba Grass seedling emergence and survival can substantially improve Gamba Grass management. Reducing re‐colonisation from the soil seed bank using residual herbicides provides a valuable management tool for land managers, integrating readily with established strategies for controlling the mature plants.     

Vegetation dynamics following trampling in grassland and heathland in Sølendet Nature Reserve, a boreal upland area in Central Norway

Trampling is recognised as a cause of disturbance in grassland and heathland vegetation along two public nature trails in Sølendet nature reserve in central Norway. The effects of trampling by visitors and of controlled trampling were monitored over a period of 5–7 years in permanent plots. A retrogressive development was recorded as vegetation cover and height were reduced and a substantial loss of species richness and biomass took place. Some species, mainly graminoids such as Agrostis capillaris and Carex vaginata , initially appeared to be more tolerant, but were eventually reduced as well. Low, geophytic and prostrate habits of growth and hardy leaf tissues seemed to be beneficial for tolerance to trampling. Moist grassland and lichen-dominated heathland were more vulnerable to trampling than dry grassland. Even though 350–1500 visitors walked through the permanent plots along the trails each summer, effects on the soil surface remained moderate and only a minor furrow was visible on the ground.     

Effects of the litter layer of Pteridium aquilinum on seed banks under experimental restoration

Questions: Does the litter layer of Pteridium aquilinum (bracken) act as a barrier to certain species in the seed bank? Does bracken control/restoration treatment affect seed transfer through the litter layer? Location: Five experiments at three sites across the UK covering two major vegetation types; acid‐grassland and heath‐land. Methods: At each experiment a range of bracken control and vegetation restoration treatments were applied for about ten years. The seed bank was sampled in both the bracken litter and the soil. The cover (%) of each species in the vegetation and the bracken litter abundance (cover and depth) was also estimated. Results: The bracken litter layer acts as an inert barrier as it contained a large proportion of seeds available in the litter‐soil profile (38%– 67% of the total). Bracken litter depth and cover also influenced significantly the seed bank composition in both the bracken litter and the soil. These effects were site‐specific, and species‐specific. The application of treatments changed significantly the balance between seed inputs and outputs in the bracken litter layer for some species. This was either a positive or negative response relative to the untreated control plots. Conclusion: For heathland and acid‐grassland restoration, the bracken litter layer may be an important seed source, but it must be disturbed particularly before seed addition.     

Establishment and reproduction of Aeschynomene virginica (L.) (Fabaceae) a rare,annual, wetland species in relation to vegetation removal and water level

Aeschynomene virginica is a rare annual plant found in freshwater tidal wetlands of the eastern United States. We hypothesized that standing vegetation and water inundation were two important environmental factors in its population dynamics. To test these hypotheses, we sowed seeds into plots with undisturbed vegetation or plots with all aboveground vegetation removed in 1998 and 1999. Presence/absence of seedlings was noted and seedling survival to reproduction, final size, and seed set were measured throughout both growing seasons. Seedling establishment from germination to the first true leaf stage increased with decreasing water depth. Vegetation removal plots had greater seedling establishment, higher seedling survival, and higher seed set per plant than non-removal plots. In a greenhouse study designed to test the effects of water level on seed germination and seedling establishment, no seedlings established in submerged soils, and seed germination and seedling establishment were lower in waterlogged soil than in wet soil. Physical stress associated with deeper water likely limits the distribution of A. virginica to higher elevations, where seeds that colonize patches with low vegetative cover are more likely to produce reproductive adults that produce more seeds relative to patches with established vegetation. A. virginica appears to be a fugitive species specializing on open habitat patches in tidal wetlands. This species may be dependent on disturbances for population establishment and maintenance.     

Short‐Term and Long‐Term Effects of Soil Ripping,Seeding, and Fertilization on the Restoration of a Tropical Rangeland

Rangeland degradation is a serious problem in semiarid Africa. Extensive areas of bare, compacted, nutrient‐poor soils limit the productivity and biodiversity of many areas. We conducted a set of restoration experiments in which all eight combinations of soil tilling, fertilization, and seeding with native perennial grasses were carried out in replicated plots. After 6 months, little aboveground biomass was produced in plots without tilling, regardless of seeding or fertilization. Tilling alone tripled plant biomass, mostly of herbaceous forbs and annual grasses. Perennial grasses were essentially limited to plots that were both tilled and seeded. The addition of fertilizer had no significant additional effects. After 7 years, vegetation had declined, but there were still large differences among treatments. After 10 years, one tilled (and seeded) plot had reverted to bare ground, but the other tilled plots still had substantial vegetation. Only one seeded grass (Cenchrus ciliaris) was still a contributor to total cover after 10 years. We suggest that restoration efforts on these soils be directed first to breaking up the surface crust, and second to the addition of desirable seed. A simple ripping trial inspired by this experiment showed considerable promise as a low‐cost restoration technique.     

Factors limiting rosette recruitment in scarlet gilia, Ipomopsis aggregata: seed and disturbance limitation

We performed a factorial combination of seed additions, surface soil disturbance, and protection from potential seed predation in experimental plots to elucidate the relative importance of each factor in the recruitment of scarlet gilia seedlings. We detected a significant interaction between seed addition and surface soil disturbance on seedling recruitment over 2 years of establishment. Plots that received both supplemental seed addition and disturbance established 10.5 times as many rosettes as control plots. We did not detect main or interactive effects of caging on seedling establishment. We explored the importance of density-dependent recruitment by investigating the number of rosettes per experimental plot through time. In addition, we used planned contrasts to compare the absolute and percent changes in control and treatment plot rosette densities between the study years. We found significant downward concave curvature to the seedling recruitment curve, suggesting negative density-dependent recruitment across the experimental range of rosette densities. We found a significant difference between the control plots and the seed addition-disturbance plots in terms of absolute changes in plot density from 1997 to 1998. Greater net mortality occurred in plots that received both seed addition and disturbance. However, we found no differences among treatments in the percent change in rosette density across the study years. Our study demonstrates that seedling recruitment in natural plant populations may be limited by the interaction of seed and microsite availability, and that seedling recruitment in scarlet gilia may be negatively density dependent. Our results suggest that the fecundity effects of particular plant-animal interactions (e.g., pollination, herbivory) may affect scarlet gilia population dynamics, particularly under conditions of high soil disturbance. Received: 11 June 1999 / Accepted: 24 November 1999     

Re-establishment of Calluna vulgaris (L.) Hull in an eight-year grazing experiment on upland acid grassland

Upland heathland is an internationally important habitat but a large area in the UK has been degraded to acid grassland by intensive livestock grazing. Re-establishment of dwarf shrubs, particularly Calluna vulgaris (L.) Hull, is a key objective for restoring heathland on these sites. A replicated plot-scale experiment was set up to examine effects of disturbance and seed addition on C. vulgaris establishment in a Nardus stricta L. grassland under three grazing regimes: sheep only (1.5 ewes ha^?1 for 10 months per year); cattle only (0.5 heifers ha^?1 in summer only); and, the cattle regime combined with sheep (1.0 ewes ha^?1 for 10 months per year). Early results of the experiment have been reported previously but it was not known if these results were an indication of the longer-term restoration success. Here we evaluate the success of the restoration methods (disturbance, seeding treatments and grazing regime) eight years after the treatments began. In seeded plots, young C. vulgaris plants had greatest above-ground height, dry weight and shoot length if grazing was excluded or the cattle-only regime was applied. C. vulgaris cover was greatest, and increased most, in plots that had been disturbed, seeded and ungrazed or subjected to the cattle-only regime. The vegetation in these plots also became more similar to reference sites with 50% or more cover of C. vulgaris. The invasive Juncus effusus L. was more frequent in disturbed and grazed plots but less frequent in plots with C. vulgaris established from added seed. Previous results that showed the benefits of disturbance and seeding treatments were still valid but changes in the vegetation composition were still occurring and longer-term studies will be needed to determine when grazing regimes including sheep might be reintroduced.     

围封对不同退化程度荒漠草原植物群落和土壤的影响

围封是退化草原生态系统恢复的有效措施之一,已在中国北方草原地区实施多年并取得良好的效果。由于不同退化草原生态系统具有完全不同的植被和土壤条件,围封对不同退化草原植物群落和土壤的恢复是否具有一致的影响,目前仍不清楚。对内蒙古地区轻度、中度和重度退化荒漠草原分别设置6年围封后,对植物群落特征和土壤理化性质进行了调查和测定。研究结果发现,围封显著提高了3种退化荒漠草原短花针茅（Stipa breviflora）和无芒隐子草（Cleistogenes songorica）种群以及群落的高度、盖度和地上生物量（P<0.05）,表明围封从多组织层次使退化草原植物群落得到有效的恢复。围封总体提高了轻度和中度退化荒漠草原植物多样性,但降低重度退化荒漠草原的植物多样性。重度退化荒漠草原在围封后群落高度、盖度和地上生物量恢复效率显著高于轻度和中度退化的（P<0.05）,表明围封对重度退化荒漠草原植被恢复更加有效。除轻度退化外,围封显著降低中度和重度退化荒漠草原土壤全碳、全氮、全磷、有效氮和速效磷含量（P<0.05）,但对3种退化荒漠草原的土壤水分含量无显著影响,表明围封对不同退化荒漠草原土壤的影响具有滞后性。研究为荒漠草原围封成效评估提供理论指导和退化荒漠草原生态系统科学合理实施围封政策提供科学依据。