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Pasture Condition of the Eastern Shore Valleys of Lake Hovsgol

Bayart Mandakh

Introduction

After passing from socialism to market economy, herdsmens increased thier personnaly livestock and. In orther to have plentiful livestock productivity, they changed thier herd composition and live for longer period in one place. Therefore pasture plant composition has changed due to improper usage of pasture land.

In recent years, Global climate change also effected on pasture plant composition, growth rate, and plants’ bioproductivity.

Study objectives

In order to determine pasture condition in six valleys, located in Eastern shore of Lake Hovsgol, we purposed to identify plant species composition and to calculate biomass in both mountain steppe and meadow zone of each valley.

Study Method

We did detailed geobotanical recordings using the method of A. P. Shennikov (1964) to determine a species composition and to estimate a canopy cover of vegetation. For the estimation of relative abundance of species we used an evaluation of O.Drude (Shennikov 1964). Nomenclature followed V. I Grubov 1982 (The Key to Vascular Plants of Mongolia).

Plant biomass samples were taken by thé method of I. A. Larin (1956). All plant biomass samples were dried in air and weigned in lab using electron balance (BONSO) with 0.1g scale. We run mathematic-statistic analyses on all data.

Results

Pasture area, on Mountain Steppe and Meadow, in different grazing intensity was calculted using ArcView 3.2 sovtware in each valley. In Turag Valley, 7.9% (366.59ha) of total pasture area in mountain steppe is overgrazed, 78.1% (3643.99ha) is moderately grased and 14.0% (653.47ha) is lightly grased. For Meadow pasture 9.2% (242.49ha) is overgrazed, 90.8% (2390.63ha) is moderately used. In Shagnuul Valley, 24.6% (556.38ha) of total pasture area in mountain steppe is overgrazed, 70.9% (1604.83ha) is moderately grazed and 4.5% (102.64ha) is lightly grased. For Meadow pasture 35.9% (802.67ha) is overgrazed, 64.1% (1434.48ha) is moderately used. In Noyon Valley, 14.4% (541.01ha) of total pasture area in mountain steppe is overgrazed, 74.3% (2789.36ha) is moderately grazed and 11.3% (423.46ha) is lightly grased. For Meadow pasture 31.2% (328.35ha) is overgrazed, 68.8% (725.18ha) is moderately used. In Sevsuul Valley, 10.1% (178.46ha) of total pasture area in mountain steppe is overgrazed, 73.4% (1293.8ha) is moderately grazed and 16.5% (291.18ha) is lightly grased. For Meadow pasture 2.8% (63.14ha) is overgrazed, 41.9% (943.09ha) is moderately used and 55.3% (1243.73 ha) is lighly used. In Dalbay Valley, 35.6% (437.04ha) of total pasture area in mountain steppe is overgrazed, 56.1% (709.92ha) is moderately grazed and 9.2% (116.45ha) is lightly grased. For Meadow pasture 27.9% (522.22ha) is overgrazed, 53.0% (990.16ha) is moderately used and 19.1% (356.7ha) is lighly used. In Borsog Valley, 4.5% (25.54ha) of total pasture area in mountain steppe is moderately grazed and 95.5% (539.26ha) is lightly grased. For Meadow, all pasture area, 100% (1179.5ha) is in condition of lighly used.

Vegetation structure and composition of the six valleys’ steppe and meadow pastures under different level of usage investigated and plant biomass (yield) determined during the 2005 growing season.

Turag Valley

  • Ovegrazed pasture of Turag Valley had sparce canopy cover of green plants (40-45%), while in some plants flattened areas it was 85-90%. The moderately used pasture canopy cover of green plants was 60-65%, and in the lightly used pasture it was 65-70%.
  • Plant growth biomass of the overgrazed south facing steppe pasture of the valley was 400kg/ha, biomass of the moderately used south facing steppe pasture was 520kg/ha, and biomass of the lightly used pasture was 1870kg/ha. In the ovegrazed south facing steppe pasture of Turag Valley, grass, sedge and forb composed 29.2-51.1%. In the lightly used pasture, there is more grass component (30.4-39.0% of total plant biomass) and litter (28.7-36.9% of the total plant biomass).
  • The ovegrazed meadow pasture of Turag Valley had cover of 55-60%, while the moderately used pasture had 85-90% and the lightly used pasture had 95-99% cover.
  • Total plant biomass of the ovegrazed meadow pasture of the valley was 748kg/ha whereas the moderately used pasture biomass was 1480kg/ha and the lightly grazed pasture biomass was 2070kg/ha. Sedge, grass, horsetale biomass composed 22.0-41.2% of the total plant biomass of the ovegrazed meadow pasture of Turag, while sedge biomass composed most portion (43.9% of the total plant biomass) of the lightly used meadow pasture.

Shagnuul Valley

  • Canopy cover of green plants of the ovegrazed south facing steppe pasture of Shagnuul Valley was sparce (60-65%), while in some areas plants was growing by lying through ground and composed 80-85% of cover. The moderately used pasture cover was 60-65% and the lightly used pasture had 70-75% cover.
  • Total plant biomass in the ovegrazed pasture of Shagnuul Valley 530kg/ha, the moderately used pasture total plant biomass was 670kg/ha and the lightly used pasture biomass was 1080kg/ha. In the ovegrazed south facing steppe pasture of Shagnuul Valley, the biomass of grass, sedge, and forb was dominants that composed 25.7-39.3% of the total plant biomass, while in the lightly grazed pasture there were more grass (55.1% of total plant biomass), and forb (19.2% of total plant biomass) and litter (15.6% of total plant biomass) was low.
  • Canopy cover of green plants of ovegrazed meadow pasture was 90-95%, the moderately used pasture’s cover was 90-95% and the lightly used pasture cover was 95-99%.
  • The ovegrazed meadow pasture in Shagnuul Valley had total of 590kg/ha plant biomass. The moderately used pasture had 1010kg/ha plant biomass and the lightly used pasture had 2280kg/ha of plant biomass. Grass and sedge biomass composed 72.1-44.6% of total plant biomass of the ovegrazed meadow pasture in Shagnuul, while in the moderately used pasture, biomass of the sedge, forb composed 53.0-57.0% of the total plant biomass. However, in the lightly used pasture the sedge biomass (45.7% of the total plant biomass) and litter (33.5% of the total plant biomass) had more biomass.

Noyon Valley

  • The ovegrazed south facing steppe pasture in Noyon Valley had 70-75% cover, while in some areas this cover reach at 80-85% because plants grow lying to the ground. The moderately used pasture cover was 75-80%.
  • Total plant biomass of the ovegrazed south facing steppe pasture in Noyon Valley was 330kg/ha, while the moderately used pasture biomass was 810kg/ha, inlightly used pasture 1030kg/ha. Forb compose 42.6-67.5% of the total plant biomass in the ovegrazed south facing steppe pasture of the Noyon Valley.
  • Vegetation cover of the ovegrazed meadow pasture was 90-95%, the moderately used meadow pasture vegetation cover was 90-95% and the lightly used meadow pasture vegetation cover was 85-90%.
  • The ovegrazed meadow pasture of Noyon Valley had 1450kg/ha of plant biomass and the moderately used meadow pasture had 1830kg/ha biomass. Sedge biomass was the most, composing 65.2-38.9% of the total plant biomass in the ovegrazed and moderately used pasture in Noyon. However, in the lightly used pasture sedge (41.6% of the total plant biomass) and litter (32.1% of the total plant biomass) biomass were more than the others.

Sevsuul Valley

  • Canopy cover of green plants of the ovegrazed south facing steppe pasture in Sevsuul was 25-30%, cover of the moderately used was 50-55% and the lightly used pasture had cover of 70-75%.
  • South facing steppe pasture of Sevsuul Valley had of 900kg/ha of total plant biomass, the lightly used pasture biomass was 1730kg/ha. Ovegrazed and moderately used south facing steppe pasture in Sevsuul Valley had dominance of forbs that composed 85.4-54.6% of the total plant biomass, while the lightly used pasture had forbs that composed 40.2% of the total plant biomass and litter that composed 44.0% of the total plant biomass.
  • Canopy cover of the ovegrazed meadow pasture in Sevsuul Valley was 80-85%, the moderately used pasture cover was 85-90% and the lightly used pasture cover was 95-99%.
  • Total plant biomass of the ovegrazed meadow pasture in Sevsuul Valley was 890kg/ha, biomass of the moderately used pasture was 1680kg/ha, and the lightly used pasture biomass was 2660kg/ha. The ovegrazed meadow pasture of Sevsuul Valley biomass was dominated by the grass and forb biomass that compose around 49.5-37.6% of the total plant biomass and the moderately used pasture biomass was dominated by the sedge, forb, litter and grass that compose 43.8-22.0% of the total plant biomass. However, the lightly used meadow pasture had more sedge (35.0% of the total plant biomass) and litter (31.0% of the total plant biomass) biomass.

Dalbay Valley

  • The ovegrazed south facing steppe pasture of Dalbay Valley canopy cover of green plants was sparse around 60-65%, moderately used pasture cover was 65-70% and the lightly used pasture cover was 70-75%.
  • Total plant biomass of the ovegrazed south facing steppe pasture in Dalbay Valley was 390kg/ha, the moderately used pasture biomass was 750kg/ga, and the lightly used pasture biomass was 1317kg/ha. The ovegrazed and the moderately used south facing steppe pasture of Dalbay Valley biomass dominated by the litter and forb biomass that compose 46.8-35.6% of the total plant biomass. The lightly used pasture biomass was dominated by the litter that compose 56.1%. However, the forb and grass biomass composed 18.3-11.0% of the total plant biomass in the lightly used pasture.
  • Cover of the ovegrazed meadow pasture was 85-90%, and the moderately used pasture cover was 90-95%.
  • Total plant biomass of the ovegrazed Dalbay Valley meadow pasture was 529kg/ha, and the moderately used pasture biomass was 1707kg/ha. The ovegrazed and the moderately used pasture biomass was 74.1-53.6% of the total plant biomass.

Borsog Valley

  • Canopy cover of green plants of the lightly used pasture in Borsog Valley was 60-65%, the lightly used pasture cover was 100% from which the green cover was 55-60% and the rest was litter cover.
  • The moderately used south facing steppe pasture in Borsog had biomass of 615kg/ha, the lightly used south facing steppe pasture of Borsog Valley biomass was 1330kg/ha from which sedge composed 39.0% and litter composed 40.8% of the total plant biomass, from which 53.6% was a litter, 26.2% was a forb, and 17.1% was a grass. In meadow pasture plant biomass is 3060kg/ha, 60.2% of these pasture was a litter, 36.0% was a sedge.

Conclusion

  • The Pasture condition study was conducted in 2005 summer in the six valleys on Eastern Shore of Lake hovsgol will be base materials to continue other reearch related this field.
  • It is required to continue this kind of research.
  • In the place, which is surrounded high mountains and big lake although the pasture areas are limited, some local herders are not initiative about properly, alternately and they are lose traditional methods to herd.
  • The herders stay in one place for 150 days in spring, summer and fall camps and induce the overgrazing when the valuable pasture plants is removed, the structure and composition is altered.

Discussion

  • Herders could stay in one camp area for no more than 35-40 days. This period is necessary because grazed plants could regenerate the organs after the grazing.
  • Herders should make short distance otor each month of the spring, summer, and fall seasons to the lightly used pasture with high litter cover. Negative effect of the long-term litter accumulation into the growth and regeneration of the plants is determined by the scientists. Therefore, it is necessary, the determined number of livestock to graze in such areas for some determined period.
  • Organize small scale training (in the scale of the family) of the traditional livestock herding techniques in cooperation with the bag and soum desicion makers. The traning should show real results from the proper scheduled use of the pasture.

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