ECOLOGICAL EVALUATION FOR SUSTAINABLE UTILIZATION OF PLANT RESOURCES OF GADOON HILLS DISTRICT SWABI, PAKISTAN

Abstract

This dissertation is multi-dimensional including floristic composition, ecological characterization, ethnobotany, vegetation structure, biomass productivity, palatability and animal preferences, mineral and nutritional analysis of some forage plants of Gadoon Hills, District Swabi, Pakistan during 2009 and 2010. There were 260 plant species belonging to 211 genera and 90 families. Asteraceae, Poaceae, Lamiaceae, Rosaceae, Papilionaceae, Brasicaceae, Euphorbiaceae, Moraceae, Polygonaceae and Caryophyllaceae were important families in the studied area. Acacia modesta, Acacia catechu, Butea frondosa and Mallotus philippensis were the well represented tree species in tropical deciduous and subtropical zones, while Pinus roxburghii, Quercus dilatata, Q. incana, Parratiopsis jacquemontiana, Lonicera quinquilocularis, Cotoneaster bacillaris, Vibernum cotinifolium and Prunus cornuta were common at high altitude. Viscum album and Korthalsella opuntia were the mistletoe and Cuscuta reflexa was the only parasite in Gadoon Hills. Shrubs like Carissa spinarum, Dodonaea viscosa, Gymnosporia royleana, Justicia adhatoda, Otostegia limbata, Sageretia theezans and Zizyphus nummularia were encountered at low altitude while Berberis lycium, Indigofera heterantha and Sarcococa saligna at the temperate zone. Apluda mutica, Aristida adscensionis, Heteropogon contortus, Chrysopogon aucheri and Themeda anathera were more or less evenly distributed in the investigated area. Some pteridophytes along with other temperate herbs like Berginia ciliate, Bistorta amplexicaulis, Valeriana jatamansii and Viola serpens were also recorded in the temperate forests. The biological spectrum showed that therophytes and megaphanerophytes were the most abundant life forms. Microphylls and leptophylls were dominant in the area. Gadoon Hills have rich plant diversity in relation to local uses. These included medicinal (149 spp.), fodder (82 spp.), fuel wood (59 spp.), vegetable (26 spp.), thatching/ roofing and sheltering (25 spp.), fruit yielding (22 spp.), fencing (17 spp.), ornamental (16 spp.), timber wood and poisonous (14 spp. each), agricultural tools making (10 spp.) and honeybee (8 spp.). viii

Based on cluster analysis the summer and winter vegetation of Gadoon Hills have been classified into three distinct vegetation types i.e. tropical , sub-tropical and temperate zone, occupying different altitudinal confines. Thirteen communities were recognized in each of the summer and winter seasons. The colour of the soil varied from brown to yellowish brown, grey brown. Soils were generally shallow and made up of sandstone and limestone. The texture of the soil varied from sandy to sandy loam. The pH of the soil ranged from 5.2 to 7.64 among the summer and winter showing almost no change. Organic matter contents differed insignificantly among the two seasons. Significant differences were observed in mineral contents among the communities while the differences among the seasons were insignificant. The plant communities inhabiting Gadoon Hills during summer and winter were mostly heterogeneous. Heterogeneity might be due to the presence of large number of annuals and habitat degradation, climate, soil conditions, deforestation, overgrazing, trampling and soil erosion in the study area. Seasonal availability of palatable fodder species depended on climate and phenological stage. It was recorded that there were 57 species available in April, 56 in May, 60 in June, 59 in July, 55 in August, 42 in September and 30 species in October. The evergreen perennial species were found throughout the year. Of the total 260 recorded species in the study area, 82 plants were palatable. Among them, 26.83% (22 Spp.) were trees, 14.63% (12 Spp.) shrubs and 58.54% (48 Spp.) species were herbs. The overall ratio of palatable species to the total recorded species was 31.54%. The total fresh biomass produced in Gadoon hills was 470303 Kg/ha shared by shrubs (344542 Kg/ha) and herbs (125761 Kg/ha). The total fresh biomass of different shrubs and herbs varied with altitudinal variations in Gadoon hills. The highest total biomass (shrubs and herbs) was observed at 500 m (63366 Kg/ha) and 600 m (61270 Kg/ha) because the tree layer has been completely destroyed and the biomass of these communities was mostly contributed by Dodonea viscosa and Zizyphus nummularia, respectively. Macro-mineral (Ca, K, Mg, Na, and N) contents recorded in the leaves of selected trees, shrubs and grasses at three phenological stages were sufficient enough that might execute the necessities of the dependent animals. Macro-mineral contents differed significantly among the forage species and among the phenological stages with some exceptions. Micro-minerals (Cd, Cr, Cu, Fe, Ni, Pb, Zn and Mn) concentrations available in these forage plants to the grazing livestock were very low, hence this may be, one of the causes responsible for the pitiable health and productivity of the grazing animals in Gadoon hills. ANOVA (P = 0.05) revealed significant difference in micro-mineral contents among the various phenological stages while insignificant difference was observed for these micro-minerals among the different plant species. The proximate composition and cell wall analysis of some fodder trees showed that dry matter of trees increased with advancing maturity. Ash level, CF was high in all tree species. EE had inconsistent trend in all tree species. In the present study protein contents decreased with advancing growth stages. Carbohydrate had inconsistent trend with advancing age. NDF contents increased with advancing growth stages only in Celtis. ADF concentrations increased with advancing maturity in some of the species while in other cases it decreased. The vegetative stages of Acacia, Celtis and Grewia had low ADL levels. Q. dilatata and Vibernum showed increase in ADL values with advancing maturity. Variations in the amount of celluloses and hemicelluloses might be due to with seasonal changes as well as with phenology. Insignificant differences occurred in DM and Ash contents among the different shrubs but differences were significant among the phenological stages. Inconsistent trend was observed in DM and ash contents among the shrubs. Significant differences in crude proteins contents were found among the different phenological stages of the analyzed shrub leaves. There were variations in TDN among species and phenological stages showing inconsistent trend. ADF concentrations decreased in Debregeasia and Rosa with maturity and this deviates from the general trend already reported. ADL showed inconsistent trend. In grasses, DM improved in Heteropogon and Themeda at advanced growth stages. The remaining species showed inconsistent trend. The present study recorded high crude fat contents in grasses species %. Maturity cause an increase in crude proteins levels in may forage plant species. The TDN increased with advancing maturity in some of the grasses while it decreased in other cases. NDF and ADL showed inconsistent trend with advancing maturity. Hemicelluloses ranged from 16.69% to 34.81% in the analyzed grasses. Cellulose contents decreased in Aristida and Themeda with advancing growth stages. Based on the present findings recommendations for sustainable utilization have also been given.