Impact of grazing system on rangeland condition and grazing capacity in Zimbabwe

2017 ◽  
Vol 39 (3) ◽  
pp. 219
Author(s):  
J. Gusha ◽  
M. Masocha ◽  
P. H. Mugabe
Keyword(s):  
Biomass Yield ◽  
Floristic Composition ◽  
Woody Species ◽  
Rangeland Management ◽  
Grass Species ◽  
Stem Density ◽  
Grazing System ◽  
Rangeland Condition ◽  
Communal Rangelands ◽  
Grazing Capacity

The influence of different land tenure and rangeland management systems on rangeland condition and livestock grazing capacity in African rangelands is not well documented. A rangeland condition assessment was carried out at 15 sites located in the communal grazing system, small-scale commercial grazing system and the large-scale commercial grazing system in Zimbabwe. Rangeland indicators assessed were: floristic composition, herbaceous biomass yield, shrub stem density and grazing capacity. Grass species composition and forage value were analysed using PROC FREQ procedure of SAS 9.3. Fisher’s exact test was performed to test for independence of the grass variables between grazing systems. A one-way ANOVA was used to test for significant differences (P < 0.05) in floristic composition, shrub stem density, herbaceous biomass yield and grazing capacity among the three grazing systems. It was observed that communal rangelands had significantly high levels of woody species, unpalatable wiry grass species, low biomass yield and were dominated by the invading shrub Helichyrsum kraussii compared with the other rangeland management systems. These results suggest that if control measures are not put in place, livestock production may not be feasible in communal rangelands in the near future because of high levels of rangeland deterioration when compared with the commercially managed rangelands. Furthermore, the observed high stem density of unpalatable woody species and the low grazing capacity of communal rangelands affect livestock production, a primary source of livelihood. This warrants a change in rangeland management system in favour of the rest-rotation grazing system, which is beneficial to both livestock and the range.

scholarly journals Floristic composition of the Montane Forest in the Almadina-Barro Preto axis, Southern Bahia, Brazil

2014 ◽  
Vol 14 (1) ◽  
Author(s):  
Macielle Macedo Coelho ◽  
André Márcio Amorim
Keyword(s):  
Species Richness ◽  
Tropical Forests ◽  
Atlantic Forest ◽  
Floristic Composition ◽  
Woody Species ◽  
Life Forms ◽  
Montane Forest ◽  
Forest Remnants ◽  
Southern Bahia ◽  
Arboreal Habit

The aim of this study is to survey the angiosperms of two montane forest remnants in the southern Bahia, Brazil: Corcovado (SCO) and Pedra Lascada (SPL). Both fragments are located in the municipality of Almadina and Barro Preto, respectively, and are 18 km distant from each other. We sampled 899 species of angiosperms distributed in 437 genera and 116 families. The SCO was the richest area with 678 species, distributed in 367 genera and 100 families. SPL showed 466 species in 269 genera and 88 families. The percentage of species identified was 85.8% and of this total, 37.7% are endemic to the Atlantic Forest, 11.2% are endemic to southern Bahia and northern Espírito Santo and 7% are disjunct between the Atlantic Forest and Amazon. The remaining percentages (44.3%) were of species widely distributed. The richest families in the two areas were Orchidaceae (10%), Rubiaceae (7%), Bromeliaceae (5.5%), Melastomataceae (4.2%) and Poaceae (4%). The richest genera were Psychotria (2%),Piper (1.8%), Ocotea (1.6%),Vriesea (1.5%) and Peperomia (1.4%). More than half of the recorded species showed non-arboreal habit, regarding life forms documented. That comes against the assertion that many authors in the tropical forests, where species richness in angiosperms is expected for non-woody species, especially in montane forests. Twelve species have been identified as new, but seven others already described from collections previously obtained in these two areas. Orchidaceae, Rubiaceae, Poaceae and Bromeliaceae showed significant richness in this study these families are commonly reported as the richest in other inventories in the Atlantic Forest in southern Bahia reinforcing their importance to the regional flora. The high levels of richness, endemism, and the growing numbers of new taxonomic discoveries from the SPL and SCO sites indicate the biological importance of these two forest remnants. The implementation of parks or other protected environmental reserves would be essential to the conservation of its species.

Fire regimes and interval-sensitive vegetation in semiarid Gregory National Park, northern Australia

2010 ◽  
Vol 58 (4) ◽  
pp. 300 ◽  
Author(s):  
Jeremy Russell-Smith ◽  
Cameron P. Yates ◽  
Chris Brock ◽  
Vanessa C. Westcott
Keyword(s):  
National Park ◽  
Fire Regime ◽  
Woody Species ◽  
Fire Regimes ◽  
Stem Density ◽  
Northern Australia ◽  
Juvenile Period ◽  
Climate Conditions ◽  
Fine Fuels ◽  
Ecologically Sustainable

Few data are available concerning contemporary fire regimes and the responses of fire interval-sensitive vegetation types in semiarid woodland savanna landscapes of northern Australia. For a 10 300 km2 semiarid portion of Gregory National Park, in the present paper we describe (1) components of the contemporary fire regime for 1998–2008, on the basis of assessments derived from Landsat and MODIS imagery, (2) for the same period, the population dynamics, and characteristic fine-fuel loads associated with Acacia shirleyi Maiden (lancewood), an obligate seeder tree species occurring in dense monodominant stands, and (3) the fire responses of woody species, and fine-fuel dynamics, sampled in 41 plots comprising shrubby open-woodland over spinifex hummock grassland. While rain-year (July–June) rainfall was consistently reliable over the study period, annual fire extent fluctuated markedly, with an average of 29% being fire affected, mostly in the latter part of the year under relatively harsh fire-climate conditions. Collectively, such conditions facilitated short fire-return intervals, with 30% of the study area experiencing a repeat fire within 1 year, and 80% experiencing a repeat fire within 3 years. Fine fuels associated with the interior of lancewood thickets were characteristically small (<1 t ha–1). Fine fuels dominated by spinifex (Triodia spp.) were found to accumulate at rates equivalent to those observed under higher-rainfall conditions. Stand boundaries of A. shirleyi faired poorly under prevailing fire regimes over the study period; in 16 plots, juvenile density declined 62%, and adult stem density and basal area declined by 53% and 40%, respectively. Although the maturation (primary juvenile) period of A. shirleyi is incompletely known, assembled growth rate and phenology data indicated that it is typically >10 years. Of 133 woody species sampled, all trees (n = 26), with the exception of A. shirleyi, were resprouters, and 58% of all shrub species (n = 105) were obligate seeders, with observed primary juvenile periods <5 years. Assembled data generally supported observations made from other northern Australian studies concerning the responses of fire-sensitive woody taxa in rugged, sandstone-derived landscapes, and illustrated the enormous challenges facing ecologically sustainable fire management in such settings. Contemporary fire regimes of Gregory National Park are not ecologically sustainable.

scholarly journals RESTORATION OF FORMER GRASSLAND IN SOUTH-CENTRAL TEXAS

2019 ◽  
Vol 71 (1) ◽  
Author(s):  
Wendy J. Leonard ◽  
O. W. Van Auken
Keyword(s):  
San Antonio ◽  
Plant Cover ◽  
Woody Species ◽  
Bare Soil ◽  
Grass Species ◽  
Herbaceous Plant ◽  
Percent Cover ◽  
Juniperus Ashei ◽  
South Central ◽  
Central Texas

Abstract In the past, grasslands and savannas were common in many areas of south-central Texas, including the San Antonio area. With the advent of European settlers and their livestock, much of this area was converted to agriculture and rangeland. Today, most of San Antonio is developed, but some preservation has occurred. Restored grassland, mechanically cleared of Juniperus ashei (juniper, Ashe juniper) and other woody species in 2013, was examined and compared to adjacent non-cleared woodland. The woodland examined was dominated by Diospyros texana (Texas persimmon) and Juniperus ashei. Richness in the woodland canopy was 15 species. The understory below the canopy had 25 woody species. In the restored grassland area, herbaceous plant cover was 41.8%, woody plant cover 5.8%, bare soil 2.9%, and litter cover 49.5%. Species richness was 71, with 60 herbaceous and 11 woody species (percent cover of each from &lt;0.1–7.1%). The most common species in the restored grassland in descending order were Nassella leucotricha (Texas winter grass), Calyptocarpus vialis (straggler daisy), Carex planostachys (cedar sedge), Sporobolus crypandrus (sand dropseed), D. texana, and Verbesina virginica (frost weed). Several C4 grass species were present with low cover but may increase in abundance over time. Four of the six most common restored grassland species were present below the woodland canopy and 12 woody species were present in the restored grassland as juveniles. Cost of restoration was approximately $38,500 ($7,500 supplies, $31,000 labor).

Effect of Aminopyralid on Canada Thistle (Cirsium arvense) and the Native Plant Community in a Restored Tallgrass Prairie

2010 ◽  
Vol 3 (2) ◽  
pp. 155-168 ◽  
Author(s):  
Travis L. Almquist ◽  
Rodney G. Lym
Keyword(s):  
Plant Community ◽  
Plant Communities ◽  
Native Species ◽  
Cirsium Arvense ◽  
Grass Species ◽  
Stem Density ◽  
Native Plant ◽  
Canada Thistle ◽  
Native Plant Community ◽  
Restored Prairie

AbstractAminopyralid efficacy on Canada thistle (Cirsium arvense) and potential to injure native species was evaluated in a restored prairie at the Glacial Ridge Preserve managed by The Nature Conservancy in Polk County, MN. Canada thistle stem density was reduced from 17 to 0.1 stems m−2 10 mo after treatment (MAT) with aminopyralid applied in the fall at 120 g ha−1. Aminopyralid also altered the composition of both Canada thistle–infested and native plant communities. Aminopyralid controlled Canada thistle and removed or reduced several undesirable forb species from the restored prairie communities, such as absinth wormwood (Artemisia absinthium) and perennial sowthistle (Sonchus arvensis). A number of high seral forbs were also reduced or removed by aminopyralid, including maximilian sunflower (Helianthus maximiliani) and purple prairie clover (Dalea purpurea). Foliar cover of high seral forbs in the native plant community was reduced from 12.2 to 7% 22 MAT. The cover of high seral grass species, such as big bluestem (Andropogon gerardii) and Indiangrass (Sorghastrum nutans) increased after aminopyralid application in both the Canada thistle–infested and native plant communities and averaged 41.4% cover compared with only 19.4% before removal of Canada thistle. Species richness, evenness, and diversity were reduced after aminopyralid application in both Canada thistle–infested and native plant communities. However, the benefits of Canada thistle control, removal of undesirable species, and the increase in native grass cover should lead to an overall improvement in the long-term stability and composition of the restored prairie plant community, which likely outweigh the short-term effects of a Canada thistle control program.

scholarly journals Preliminary Study of the Effect of Chemical and Organic Fertilizers on a Semi-Natural Grassland in Vlăhiţa, Harghita Mountains, Romania

2020 ◽  
Vol 3 (2) ◽  
pp. 56-65
Author(s):  
Katalin Molnár ◽  
Imre-István Nyárádi ◽  
Béla Bíró-Janka ◽  
István Simó ◽  
János Bálint ◽  
...  
Keyword(s):  
Nutritional Value ◽  
Biomass Yield ◽  
Organic Fertilizer ◽  
Floristic Composition ◽  
Control Plot ◽  
Organic Fertilizers ◽  
Anthropogenic Pressure ◽  
Soil Mineral Nitrogen ◽  
Qualitative Structure ◽  
Natural Grassland

AbstractThe aim of the research was to examine the effect of different fertilizers on the floristic composition and biomass yield of the semi-natural grassland used as hayfield near Vlăhița locality (Harghita County, Romania) in order to improve its management. In the same time the qualitative structure of the studied grassland was evaluated after the first application of the fertilizers. The vegetation survey was made before mowing, and a total of 84 plant taxa were identified. The studied plant community belongs to the association Festuco-Agrostetum capillaris Horv. 1951. From the 31 fodder species, 13 had very good or good nutritional value. The qualitative structure analysis indicates that the vegetation has developed under moderate anthropogenic pressure. Beside the Euro-Asian elements the Circumpolar and the Cosmopolite elements were well represented. Many species with high tolerance for temperature, soil pH, and soil mineral nitrogen content were registered. After the first application of fertilizers in all treated plots the biodiversity increased compared to the control plot. Fertilized plots also had a significantly higher biomass yield than the control plot. All fertilizers reduced the proportion of the species with good nutritional value from the Poaceae family. Organic fertilizer affected positively the proportion of other plant families than Poaceae and Fabaceae. Long-term experiments are necessary to evaluate the response of the vegetation on treatment with organic fertilizer in order to optimize productivity of the hayfield and sustain species richness.

scholarly journals Floristic composition of oak forests and oriental hornbeam scrubs on mt. Vidlič in the first three years after a wildfire

2018 ◽  
pp. 11-28
Author(s):  
Ljubinko Rakonjac ◽  
Marija Marković ◽  
Biljana Nikolić ◽  
Aleksandar Lučić ◽  
Tatjana Ratknić
Keyword(s):  
Forest Fires ◽  
Recovery Time ◽  
Continuous Monitoring ◽  
Floristic Composition ◽  
Grass Species ◽  
Oak Forests ◽  
First Year ◽  
Complete Destruction ◽  
Composition And Structure ◽  
Previous State

After a catastrophic wildfire on Vidlič Mountain in 2007, which among other things burned oak forests and hornbeam scrubs, their floristic composition was monitored for three years. Phytosociological surveys were carried out in the field using the Braun-Blanquet method, and the results are presented in the form of a synthetic phytosociological table. It was observed that in the stands in which the vegetation was only partially damaged, a shorter recovery time was required to return to the previous state - as it was before the wildfire. The initial stages of vegetation recovery at sites where complete destruction of vegetation occurred were characterized by a strong presence of annual therophytes: Orlaya grandiflora, Sideritis montana, Geranium dissectum, Althaea hirstuta. The first year after the wildfire was characterized by the dominance of annual species of Bupleurum praealtum, Crepis setosa and Centaurea calcitrap, which were not recorded in the monitored stands in the second and third year after the wildfire. In the second and third year after the wildfire, perennial plants and various grass species assumed dominance. It is necessary to conduct further systematic and continuous monitoring of the floristic composition and structure of the oak forests that completely burned in the wildfire, as well as an analysis of the profitability of the restitution of oak forests damaged by forest fires in Serbia.

scholarly journals Short Communication: Floristic composition and relationships between plant species abundance and soil properties in common hazel (Corylus avellana) mountainous forest of northern Iran

2018 ◽  
Vol 19 (5) ◽  
pp. 1835-1841
Author(s):  
GHADER POURRAHMATI ◽  
ASADOLLAH MATAJI ◽  
HASSAN POURBABAEI ◽  
ALI SALEHI
Keyword(s):  
Soil Properties ◽  
Plant Species ◽  
Short Communication ◽  
Species Abundance ◽  
Floristic Composition ◽  
Woody Species ◽  
Corylus Avellana ◽  
Herbaceous Species ◽  
Northern Iran ◽  
Total N

Pourrahmati G, Mataji A, Pourbabaei H, Salehi A. 2018. Short Communication: Floristic composition and relationships between plant species abundance and soil properties in common hazel (Corylus avellana) mountainous forest of northern Iran. Biodiversitas 19: 1835-1841. Mountainous forests are valuable terrestrial ecosystems because of their useful services for the human being. Here, we explored the floristic composition and the relationships between plant species abundance distribution and soil physical and chemical properties in common hazel (Corylus avellana L.) in the mountainous forest of northern Iran. Within the forest stand, 30 quadrats (20 m × 20 m and 1 m × 1 m for woody and herbaceous species, respectively) were selectively sampled along an altitudinal range from 1300 m to 1800 m a.s.l. to assess plant species composition and abundance, and soil samples were taken to perform chemical and physical analyses. The results showed that a total of 43 herbaceous and 15 woody species belonging to 23 and 8 families were identified. The abundance of herbaceous species was significantly correlated with soil properties (pH and total N). Furthermore, the abundance of woody species had a non-significant correlation with soil properties.

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