Clearing savannas for use as rangelands in Queensland: altered landscapes and water-erosion processes

2002 ◽  
Vol 24 (1) ◽  
pp. 83 ◽  
Author(s):  
J. Ludwig ◽  
D. Tongway
Keyword(s):  
Woody Debris ◽  
Perennial Grass ◽  
Canopy Cover ◽  
Ground Cover ◽  
Perennial Grasses ◽  
Woodland Birds ◽  
Erosion Processes ◽  
Run Off ◽  
Tree Layer ◽  
Open Woodland

This paper presents a framework and some examples of how tree clearing alters landscapes (vegetation structure and faunal habitat) and processes (run-off and soil erosion) for eucalypt savannas in Queensland. Unaltered savannas have a tree-layer and a well-covered ground-layer of perennial grasses, and they provide habitats favoured by a variety of open woodland birds, reptiles and small mammals. Because unaltered savannas have a high ground-cover, they have low rates of run-off and erosion. When savannas are chained, but otherwise unaltered, trees rapidly regrow and increase in canopy cover. The exotic buffel grass often establishes in chained regrowth (especially if grazed), although the cover of native grasses such as black speargrass remains high (unless heavily grazed). We found that open woodland birds declined on these chained regrowth sites, except for the Weebill, which increased in abundance. When savannas are cleared of trees and woody debris and developed as improved pasture systems, both exotic and native perennial grass increased in cover. However, open woodland fauna abundance declined whereas grassland fauna such as the Red-backed Fairy-wren and the House Mouse increased in abundance. If these pasture sites are heavily utilised by livestock so that ground-cover is reduced, rates of run-off and soil loss are likely to rapidly increase, especially as cover declines below 40%. These run-off and erosion findings suggest that the manner in which savanna landscapes are cleared and subsequently used will have flow-on effects at catchment scales.

Management of Ventenata dubia in the inland Pacific Northwest with indaziflam

2019 ◽  
Vol 12 (4) ◽  
pp. 223-228 ◽  
Author(s):  
Lindsay E. Koby ◽  
Timothy S. Prather ◽  
Harold Quicke ◽  
Jared Beuschlein ◽  
Ian C. Burke
Keyword(s):  
Pacific Northwest ◽  
Plant Biomass ◽  
Perennial Grass ◽  
Canopy Cover ◽  
Perennial Grasses ◽  
Minimal Impact ◽  
Weedy Species ◽  
Winter Annual ◽  
Cover Class ◽  
Visual Assessments

AbstractVentenata [Ventenata dubia (Leers) Cross] is a winter annual grass relatively new to the inland Pacific Northwest that is capable of displacing desired vegetation. Indaziflam was evaluated for the management of V. dubia on two Conservation Reserve Program (CRP) sites near Moscow, ID, and Pullman, WA. While perennial grasses were dormant, applications of indaziflam in mixture with various herbicides were made in spring 2016. Treatment effects were evaluated for 2 yr by visual assessments of community composition and canopy cover of V. dubia and other non-weedy species (assessments occurred 3 to 6 mo after treatment, depending on location) and by representative cover class assessments. Biomass samples of all plant species were collected in the summer of 2017. Reduced V. dubia cover was observed in 2016, except when glyphosate was used alone. In 2017 indaziflam applied alone or in mixture with rimsulfuron effectively controlled V. dubia with minimal impact on desirable vegetation. Plant biomass from nontreated plots averaged 40 g m−2 for V. dubia and 100 to 179 g m−2 for perennial grasses. Plant biomass averaged <11 g m−2 for V. dubia and 371 to 490 g m−2 for perennial grasses when indaziflam at 102 g ai ha−1 plus glyphosate at 474 g ai ha−1 was applied. Smooth brome (Bromus inermis Leyss.) biomass was positively associated with the reduction of V. dubia, and there was a decrease in diversity associated with the removal of V. dubia through effective treatments. Indaziflam is an effective tool for the management of V. dubia in perennial grass stands, and spring applications of indaziflam should be in mixture with herbicides with POST activity.

The Influence of Recent Grazing Pressure and Landscape Position on Grass Recruitment in a Semi-Arid Woodland of Eastern Australia.

1996 ◽  
Vol 18 (1) ◽  
pp. 3 ◽  
Author(s):  
VJ Anderson ◽  
KC Hodgkinson ◽  
AC Grice
Keyword(s):  
Seedling Emergence ◽  
Perennial Grass ◽  
Soil Surface ◽  
Grazing Pressure ◽  
Perennial Grasses ◽  
Run Off ◽  
Eastern Australia ◽  
Annual Grasses ◽  
History Of ◽  
Semi Arid

This study examined the effects of previous grazing pressure, position in the landscape and apparent seed trapping capability of soil surface micro-sites on recruitment of the perennial grass Monachather paradoxa (mulga oats) in a semi-arid woodland. Seedling emergence was counted on small plots which had been kept moist for one month. The plots were on bare ground, or at grass tussocks, or at log mounds, sited in the run-off, interception and run-on zones of paddocks that had been grazed for six years at 0.3 and 0.8 sheep equivalent/ha. Few naturally occurring perennial grass seedlings emerged on any of the sites. The level of previous grazing pressure influenced the recruitment of grasses from natural sources as well as from seed of M. paradoxa broadcast on the soil surface; significantly more grass seedlings recruited in paddocks stocked at 0.3 than at 0.8 sheep/ha. Emergence of the sown grass did not differ significantly between the three zones in the landscape, but trends in the data suggest the interception zone may have been the most favourable. Recruitment from in situ grass seed was highest in the mulga grove (run-on) zone. Most seedlings of the sown grass emerged around the bases of existing perennial grass tussocks, but recruitment of volunteer perennial and annual grasses was more evenly distributed between the mulga log-mounds and perennial grass tussocks. It is concluded that very low levels of readily germinable seed of perennial grasses remained in the soil at the end of the drought and that areas with a history of high grazing pressure have less probability of grass recruitment when suitable rain occurs.

Ground cover in temperate native perennial grass pastures. I. A comparison of four estimation methods

2002 ◽  
Vol 24 (2) ◽  
pp. 288 ◽  
Author(s):  
S. R. Murphy ◽  
G. M. Lodge
Keyword(s):  
Image Analysis ◽  
Digital Image ◽  
Digital Image Analysis ◽  
Perennial Grass ◽  
Canopy Cover ◽  
Ground Cover ◽  
Estimation Methods ◽  
Visual Estimation ◽  
Pasture Production ◽  
Point Quadrat

Studies were conducted to compare visual estimates of ground cover and canopy cover by both inexperienced and experienced observers and to compare those estimates with those from more objective methods in native pastures in the high rainfall, temperate rangelands of northern NSW. Ground cover and canopy cover of 60 quadrats was estimated using visual, mapped area, digital image analysis and photo point quadrat methods. Inexperienced observers were trained by estimating ground cover of reference quadrats. Differences between mean visual estimates of ground cover and canopy cover for experienced and inexperienced observers were not significant (P>0.05). Mean ground cover estimates by the mapped area, digital image analysis and point quadrat methods were also not different from each other. The overall relationship between mean visual estimate and mean objective estimate of ground cover was non-linear (second order polynomial, R2 = 0.93), observers tending to underestimate in the mid-range (20 to 80%) of cover compared with objective methods. Mean visual estimate of ground cover was 73.7% compared with the mean objective estimate of 83.7%. Visual estimates of canopy cover (mean 34.6%) were highly correlated (R2 = 0.90) with those of the mapped area method (mean 34.3%) and the relationship was linear. Measurement of ground cover is a standard technique used in many pasture ecology and management studies and is increasingly being used by land managers to monitor pasture production and sustainability. Inexperienced observers were trained quickly and easily to estimate ground cover and canopy cover with sufficient accuracy to identify ranges of cover using visual estimation, indicating that the visual estimation technique should be suitable for estimating ground cover in land management research.

Temporary cropping in semi-arid shrublands increases native perennial grasses

2011 ◽  
Vol 33 (1) ◽  
pp. 67 ◽  
Author(s):  
Y. Alemseged ◽  
R. B. Hacker ◽  
W. J. Smith ◽  
G. J. Melville
Keyword(s):  
Perennial Grass ◽  
Stable State ◽  
Ground Cover ◽  
Perennial Grasses ◽  
Grazing Management ◽  
Alternative Stable State ◽  
Pasture Production ◽  
Native Grasslands ◽  
Native Shrubs ◽  
Semi Arid

Thickening of native shrubs is a major problem in many ‘semi-arid woodlands’ as significant increase in shrub density is often negatively correlated with herbaceous vegetation and leads to reduced pasture production and soil erosion. This project aimed to test the hypothesis that temporary cropping (up to three crops in 15 years) consistently increases the density of native perennial grasses following the removal of shrubs. A total of 30 paddocks that had been cropped during the last 20 years were randomly selected using a satellite-based database that documented annual clearing and cropping history from 1987 to 2003. Paddocks were classified into four types based on clearing and cropping history and grazing management – not cleared (shrubs), regrowth (re-invaded by shrubs), set stocked (cropped and grazed), light/rotationally grazed (cropped and grazed). The responses of vegetation and soil (chemical and physical) properties to clearing and cropping were evaluated. Results indicated that ground cover, native perennial grass cover and standing dry matter were highest under light/rotationally grazed conditions. The shrub state represents a stable state within the Cobar pediplain brought about due to land-use change in the form of overgrazing and/or the removal of fire from the system. An alternative stable state was achieved as a result of disturbance in the form of clearing, cropping and grazing management thereby directly altering the shrub population. The resilience of this state is largely dependent on the grazing management system used and on the prevention of shrub from re-establishing while failure to control shrubs could lead to the re-emergence of the Shrub State. We conclude that native grasslands do regenerate following cropping after removal of shrubs. The importance of grazing management for restoring perennial ground cover following removal of shrubs and temporary cropping has been clearly demonstrated by the study.

Effects of nitrogen and phosphorus on vegetation dynamics of a degraded native grassland in semi-arid south-eastern Australia

2011 ◽  
Vol 33 (1) ◽  
pp. 87 ◽  
Author(s):  
R. B. Hacker ◽  
I. D. Toole ◽  
G. J. Melville
Keyword(s):  
Vegetation Dynamics ◽  
Plant Density ◽  
Perennial Grass ◽  
Ground Cover ◽  
Perennial Grasses ◽  
Grass Species ◽  
Nitrogen And Phosphorus ◽  
Mineral N ◽  
Eastern Australia ◽  
Semi Arid

The roles of nitrogen (N) and phosphorus (P) in controlling vegetation transitions in a degraded semi-arid grassland were investigated in a factorial experiment that combined two initial levels of perennial plant density (low and high), three levels of N (N+, N0 and N–) and two levels of P (P+ and P0). Increased levels of both N and P were achieved by fertiliser addition while sucrose was used to reduce the level of N. Vegetation dynamics were driven primarily by soil N rather than P. Addition of sucrose, which was inferred to result in the immobilisation of mineral N, reduced the growth of annual species and facilitated the establishment and growth of native perennial grasses. Addition of P generally had no significant effect on dry matter production, either in total or for species grouped as forbs, annual grasses and perennial grasses, or on recruitment and mortality of perennial grasses. However, at some times of observation addition of P increased ground cover and/or the basal circumference of some perennial grass species. Basal circumference for Enteropogon acicularis was also increased by addition of N. Soil biological activity, measured by decomposition of cotton strips, was increased by addition of N, which maintained vegetation in an annual-dominated condition, and was not affected by addition of P. Carbon addition has the potential to assist restoration of this grassland. However, the capacity of some native grass species to respond to increased fertility suggests that once restoration is achieved some increase in fertility may be beneficial for pastoral production.

scholarly journals Succession Effects on Mammal and Inverterbrate Communities 26 Years After the 1988 huckleberry Mountain Fire

2014 ◽  
Vol 37 ◽  
pp. 49-57
Author(s):  
Hayley Lanier ◽  
Andy Kulikowski ◽  
R. Seville ◽  
Zachary Roehrs ◽  
Meredith Roehrs
Keyword(s):  
Small Mammal ◽  
Woody Debris ◽  
Canopy Cover ◽  
Ground Cover ◽  
Fire Season ◽  
Long Term Effects ◽  
Mammal Species ◽  
Ecological Processes ◽  
Long Term Study

Fires are an important and increasingly common driver of habitat structure in the intermountain West. Through an ongoing study of burned and adjacent unburned areas along the John D. Rockefeller, Jr. Memorial Parkway, we examine the long-term effects of the 1988 fire season on community assembly, succession, and ecological processes. We collected mark/recapture data on rodents, removal data for insectivorous mammals and invertebrates, and habitat measurements on four grids in 2014 and combined these results with previous survey data. In 2014, 4,800 trap nights yielded 13 species of small mammals, comprising 618 individuals. Macroarthropod abundance was higher on burned grids, but diversity was higher on unburned grids. In contrast, springtail (Collembola) diversity was higher on burned grids, but abundance was highest in unburned grids. Since the beginning of this long-term study, the total number of mammal species has increased across all sites, and relative abundance in burned areas has shifted from early successional species (Peromyscus maniculatus) to those more associated with old growth forests (such as Myodes gapperi). Other than in 1991, the burned grids have harbored more diverse small mammal communities than the unburned control grids. Significant, long-term differences in vegetation based upon burn history were observed, including different ground cover, less canopy cover, and more coarse woody debris in burned sites. This work provides a unique long-term picture of the interrelationships of small mammal and invertebrate communities and correlated habitat variables as these ecosystems undergo post-fire succession.

Studies of competition between Nassella trichotoma (Nees) Hack. ex Arechav. (serrated tussock) and native pastures. 2. Seedling responses

2008 ◽  
Vol 59 (3) ◽  
pp. 237 ◽  
Author(s):  
W. B. Badgery ◽  
D. R. Kemp ◽  
D. L. Michalk ◽  
W. McG. King
Keyword(s):  
Dry Matter ◽  
Seedling Recruitment ◽  
Perennial Grass ◽  
Ground Cover ◽  
Perennial Grasses ◽  
Native Grass ◽  
Eastern Australia ◽  
Native Pastures ◽  
Grass Weed ◽  
Native Perennial Grass

Native perennial grass competition can substantially reduce the invasion of Nassella trichotoma (serrated tussock), a major perennial grass weed problem in south-eastern Australia. This paper reports on a field experiment that investigated the recruitment of N. trichotoma seedlings, and determined what level of native grass competition was needed to prevent establishment in the central-west of NSW. Grasslands that maintained >2 t dry matter (DM)/ha and 100% ground cover (measured in spring) prevented N. trichotoma seedling recruitment. Relatively small amounts of perennial grass (>0.5 t DM/ha measured in spring) resulted in mortality of N. trichotoma seedlings that had recruited earlier in the year, through the next summer. Flupropanate also markedly reduced native perennial grasses and substantially increased N. trichotoma seedling establishment 12 months after application. Rotational grazing to maintain adequate levels of DM was an important management tactic that prevented N. trichotoma establishment and survival.

Medusahead Control with Fall- and Spring-Applied Herbicides on Northern Utah Foothills

2005 ◽  
Vol 19 (3) ◽  
pp. 653-658 ◽  
Author(s):  
Thomas A. Monaco ◽  
Travis M. Osmond ◽  
Steven A. Dewey
Keyword(s):  
Perennial Grass ◽  
Ground Cover ◽  
Perennial Grasses ◽  
Primary Concern ◽  
Annual Grass ◽  
Bare Ground ◽  
Prescribed Burns ◽  
Northern Utah ◽  
Winter Annual ◽  
Second Year

Medusahead is an aggressive, nonnative, winter annual grass that infests rangelands in the western United States. Its ability to rapidly spread, outcompete native vegetation, and destroy forage potential is a primary concern for landowners and land managers exposed to this weed. Prescribed burns were conducted at a low- and high-litter site in northern Utah prior to conducting experiments to evaluate the effects of fall and spring applications of sulfometuron at 39 or 79 g ai/ha and imazapic at 70 or 140 g ai/ha on medusahead and associated perennial grasses, annual and perennial forbs, and bare ground cover. Large differences in pretreatment medusahead litter between the sites resulted in less surface area burning at the low-litter site (∼10%) compared to the high-litter site (∼80%). Higher herbicide rates significantly increased medusahead control and bare ground cover; however, this rate affect largely depended on site, season, and herbicide. The low- and high-litter sites did not differ significantly in perennial grass cover 2 yr after burning. Annual forb cover was greater, but perennial forb cover was lower at the low-litter site compared to the high-litter site. Several treatment combinations were identified as having the potential to maintain greater than 50% medusahead control in the second year after herbicide applications. These results collectively demonstrate that potential exists to successfully control medusahead and produce a window of opportunity to reintroduce a greater abundance of perennial species back into the plant community via seeding.

Ground cover in temperate native perennial grass pastures. II. Relationship with herbage and litter mass

2002 ◽  
Vol 24 (2) ◽  
pp. 301 ◽  
Author(s):  
G. M. Lodge ◽  
S. R. Murphy
Keyword(s):  
Total Mass ◽  
Perennial Grass ◽  
Ground Cover ◽  
Ground Level ◽  
Perennial Grasses ◽  
Litter Mass ◽  
The Mean ◽  
Native Pastures ◽  
The Individual ◽  
The Relationship

Studies were conducted to examine the relationship between ground cover and herbage mass; ground cover and litter mass; herbage mass and litter mass, and, ground cover and total (herbage and litter) mass for two grazed, native pastures in the high rainfall, temperate rangelands of northern NSW. Ground cover was visually estimated by two experienced observers, litter (unattached plant material) was collected and herbage mass was estimated by harvesting to ground level in 30 quadrats (40 by 40 cm). Data were collected for 16 sampling times at the change of season and from spring 1997 to spring 2000 (a total of 465 quadrats at each site) and examined by regression analysis for the mean data for each level of ground cover and for data from individual quadrats. The relationship between ground cover and herbage, litter or total mass was logarithmic at each site. The logarithmic nature of the relationship reflected the occurrence of low herbage, litter and total mass even when ground cover was 100%. For the mean data, herbage and total mass accounted for 68–77% of the variation in ground cover, but for the individual quadrat data these variables accounted for 42–53% and 43–55%, respectively of this variation. Litter and herbage mass had a low correlation (R2<~0.20) and for the mean data litter mass accounted for around 40–60% of the variation in ground cover, compared with 15–21% for the individual quadrats. Some seasonal differences in these relationships were apparent and these were attributed to the occurrence of annual forb and legume species that had different growth habits to those of the native perennial grasses. For these pastures the data indicated that herbage mass could not be used as a surrogate measure of ground cover or litter mass.

Effects of logging and fire on small mammals in Mumbulla State Forest, near Bega, New South Wales

1987 ◽  
Vol 14 (2) ◽  
pp. 163 ◽  
Author(s):  
D. Lunney ◽  
B. Cullis ◽  
P. Eby
Keyword(s):  
Small Mammals ◽  
New South ◽  
New South Wales ◽  
Canopy Cover ◽  
Ground Cover ◽  
First Year ◽  
Severe Effect ◽  
South Wales ◽  
Antechinus Stuartii ◽  
Rattus Fuscipes

This study of the effects of logging on small mammals in Mumbulla State Forest on the south coast of New South Wales included the effects of a fire in November 1980 and a drought throughout the study period from June 1980 to June 1983. Rattus fuscipes was sensitive to change: logging had a significant impact on its numbers, response to ground cover, and recapture rate; fire had a more severe effect, and drought retarded the post-fire recovery of the population. The three species of dasyurid marsupials differed markedly in their response to ground cover, canopy cover, logging and fire. Antechinus stuartii was distributed evenly through all habitats and was not affected by logging, but fire had an immediate and adverse effect which was sustained by the intense drought. A. swainsonii markedly preferred the regenerating forest, and was not seen again after the fire, the failure of the population being attributed to its dependence on dense ground cover. Sminthopsis leucopus was found in low numbers, appeared to prefer forest with sparse ground cover, and showed no immediate response to logging or fire; its disappearance by the third year post-fire suggests that regenerating forest is inimical to the survival of this species. Mus musculus showed no response to logging. In the first year following the fire its numbers were still very low, but in the next year there was a short-lived plague which coincided with the only respite in the 3-year drought and, importantly, occurred in the intensely burnt parts of the forest. The options for managing this forest for the conservation of small mammals include minimising fire, retaining unlogged forest, extending the time over which alternate coupes are logged and minimising disturbance from heavy machinery.

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