4 results
Rehabilitation of degraded grasslands in north Syria: use of farmer participatory research to encourage the sowing of annual pasture legumes
- F. GHASSALI, P. S. COCKS, A. E. OSMAN, G. GINTZBURGER, S. CHRISTIANSEN, A. SEMAAN, M. LEYBOURNE
-
- Journal:
- Experimental Agriculture / Volume 35 / Issue 4 / October 1999
- Published online by Cambridge University Press:
- 30 March 2001, pp. 489-506
-
- Article
- Export citation
-
A series of experiments on communally-owned grasslands in the barley–livestock zone of north Syria were conducted to test the hypothesis that introduction of Mediterranean annual legumes will increase productivity. The experiments were preceded by a survey to determine farmers' attitudes, describe the farming systems and to select appropriate collaborators. The first experiment examined the establishment of medics (Medicago spp.) and clovers (Trifolium spp.) distributed by hand, and monitored their effects on biomass and seedbank size. Later experiments extended these results to other villages. The principles of farmer participation in research were used to overcome the constraints imposed by the communal ownership of land.
The survey revealed that the average size of the 20 villages was 36 families and that each village owned 887 sheep and 790 ha land. All villages had access to communally-owned grasslands, although their dependence on income from sheep varied greatly. These villages were subsequently divided into groups of high, intermediate and low potential.
Of the 11 clovers sown in the first experiment, seed numbers of T. tomentosum, T. purpureum, T. haussknechtii, T. pilulare and T. resupinatum increased over three years. By 1996, there were more than 3000 legume seeds m−2 in the seeded treatment compared with less than 2000 in the unseeded treatment (mainly the naturally-occurring Trigonella monspeliaca). The number of medic and clover seedlings also increased significantly, while the number of Trigonella seedlings decreased significantly. Biomass production increased in the final two years and there was no response to added phosphorus.
There were similar results in the later experiments. Seedbank size was greater in seeded treatments than in unseeded treatments, there were more seedlings in the seeded treatments, and the most successful species were T. campestre, T. tomentosum, T. speciosum and M. rigidula. The response in biomass was limited to the legume component, although total biomass increased in at least one of the two years. The highest biomass produced was 1112 kg ha−1 and there was no response to added phosphorus.
The results suggested that the on-station research previously conducted at ICARDA headquarters was applicable to communally-owned land, although important modifications were needed. For example, at ICARDA phosphorus was necessary to stimulate the growth of legumes; in contrast, it was necessary to sow legumes at the four villages involved in these experiments. The results also suggested that the grasslands were common property, owned and controlled by defined groups of farmers.
REHABILITATION OF DEGRADED GRASSLANDS IN NORTH SYRIA: THE USE OF AWASSI SHEEP TO DISPERSE THE SEEDS OF ANNUAL PASTURE LEGUMES
- F. GHASSALI, A. E. OSMAN, P. S. COCKS
-
- Journal:
- Experimental Agriculture / Volume 34 / Issue 4 / October 1998
- Published online by Cambridge University Press:
- 30 March 2001, pp. 391-405
-
- Article
- Export citation
-
Four experiments were conducted to facilitate the improvement of degraded grasslands in north Syria. The first examined the survival of legume seeds fed to penned Awassi wethers. The second and third observed the germination and establishment of legumes from faecal pellets in the field and in a glasshouse respectively. The fourth explored the possibility of transporting seeds from legume-rich (source) to legume-poor (target) grasslands using commercial flocks on communally-owned land. Seeds of small-seeded clovers passed through sheep in greater numbers (58–72%) than did seeds of larger-seeded species (10–40%). Of the clover seeds Trifolium campestre (seed size 0.45 mg) disintegrated least (72% passage) and T. haussknechtii (seed size 2.68 mg) disintegrated most (10% passage). Recoveries of Medicago noeana and Scorpiurus muricatus seeds were larger than expected on the basis of their seed sizes. Maximum rate of recovery was at 36 h after the seed meal for all species, all seeds were recovered by 120 h and 90% of the recovered seeds were passed in 72 h. Ingestion had little effect on the hardness and viability of most seeds. Experiments 2 and 3 suggested that seeds in pellets germinated and established as successfully as naked seeds. Burial increased establishment, whether in the field or under conditions of low moisture stress in the glasshouse. The small-seeded clovers, T. tomentosum and T. campestre, established most successfully whether from pellets or from naked seeds. About 500 seeds m−2 were successfully transported from the source to the target grassland. About half were Trigonella monspeliaca, a naturally-occurring legume found on both the source and target grasslands. Of the species sown on the source grassland, 115 seeds m−2 of Trifolium campestre (33% of the source seed bank), 62 seeds m−2 of T. tomentosum (27%) and 78 seeds m−2 of T. purpureum (21%) were detected in the target. Few medics were transported (for example, <2% of M. noeana). Apart from Trigonella monspeliaca, Trifolium tomentosum (16 plants m−2) was the most frequent species found in the target grassland in the following April. The results suggest that using sheep is a cheap and practical way of dispersing the seeds of pasture legumes and thereby improving the degraded grasslands of north Syria. They clearly demonstrate the role of small-seeded legumes (<1 mg) in grassland improvement, especially the small-seeded clovers.
Productivity and botanical composition of Mediterranean grassland in relation to residual phosphate
- A. E. OSMAN, A. K. SALKINI, F. GHASSALI
-
- Journal:
- The Journal of Agricultural Science / Volume 132 / Issue 4 / June 1999
- Published online by Cambridge University Press:
- 01 June 1999, pp. 399-405
-
- Article
- Export citation
-
The effects of residual phosphate (P) fertilizer were monitored for six seasons on Mediterranean grassland. The phosphate fertilizer was originally applied annually at three rates (0, 25 and 60 kg P2O5/ha) for 7 years (1984–1990) to phosphate-deficient grassland at Tel Hadya, northern Syria. The herbage biomass productivity, botanical composition and the seed bank in the soil were monitored for six seasons (1991/92–1996/97). The experiment was grazed at two annual stocking rates (1·1 sheep/ha (low) and 2·3 sheep/ha (high)). The experimental site was typical of native grassland within the cereal zone of west Asia, where cropping is not possible because of shallow, stony soils and steep slopes.
Available soil phosphorus in May 1991 was 6·5, 20·8 and 40·1 mg P/kg under the 0, 25 and 60 kg P2O5/ha treatments and 6·6, 13·4 and 14·8 mg P/kg respectively, in May 1997. Yields of both legumes and total herbage (legume+grass+other species) were significantly influenced by the residual phosphate. Legume yields were between 6- and 7-times the control yield in the first two years of the study. This decreased with time but was still in the range of 1·5 to 1·9 times the yield of the control in 1997, six years later. Total herbage yield was consistently higher on the plots previously fertilized with P, which ranged between 1·5- and 2·5-times the control. Both legume seed and grass seeds were significantly larger with residual P, which ranged between 5·4- and 2·0-times the control for the legume and 2·5- and 1·4-times for the grasses. All these factors have practical implications for the use of P fertilizer on grassland which could help control soil erosion and improve livestock production on marginal lands on which farming communities largely depend.
EFFECTS OF STORAGE CONDITIONS AND PRESENCE OF FRUITING BRACTS ON THE GERMINATION OF ATRIPLEX HALIMUS AND SALSOLA VERMICULATA
- A. E. OSMAN, F. GHASSALI
-
- Journal:
- Experimental Agriculture / Volume 33 / Issue 2 / April 1997
- Published online by Cambridge University Press:
- 01 April 1997, pp. 149-155
-
- Article
- Export citation
-
Two shrub species, Atriplex halimus L. and Salsola vermiculata L., are considered useful for rehabilitation of degraded rangelands in west Asia and north Africa. They can be established from direct seeding and are capable of self-sowing. In this study, seed storage at different temperatures and the influence of fruiting bracts on seed germination were examined for the two species during two seasons. Fruits (utricles) were stored at 20–22°C (room temperature), 0°C or −22°C. Germination tests were carried out after 33, 56, 90, 152, 272 and 397 d in storage in the first season and after 44, 76, 104, 170, 288 and 412 d in the second season. Seeds were germinated in their fruiting bracts or after bract removal. Bract removal significantly improved seed germination of both shrubs regardless of storage temperature. For S. vermiculata the increase in germination was in the range of 1.3- to 14.7-fold compared with values for the intact fruit in Season 1 and 0.5 to 3.8 in Season 2. Similarly the ranges for A. halimus were 0.5- to 4.2-fold and 0.7- to 5.3-fold in the two seasons respectively. The effect of cold storage was greater on Salsola than on Atriplex. The reduction of the storage temperature from 21°C to 0°C and −22°C increased the longevity of S. vermiculata seeds by 2.8–46.6 times in Season 1 and by 2.9–2.6 times in Season 2. There was little or no effect on the longevity of A. halimus. A leachate prepared by soaking fruiting bracts from S. vermiculata significantly depressed germination (p < 0.01), the effect being greater on Salsola seeds (20% reduction) than on Atriplex seeds (8% reduction). A leachate from A. halimus produced a slight but non-significant reduction in germination.