Eco-Floristic studies of native plants of the Beer Hills along the Indus River in the districts Haripur and Abbottabad, Pakistan.

The present study was conducted to elaborate vegetation composition structure to analyze role of edaphic and topographic factors on plant species distribution and community formation during 2013-14. A mixture of quadrat and transect methods were used. The size of quadrat for trees shrubs and herbs were 10 × 5, 5 × 2, 1 × 1 meter square respectively. Different phytosociological attribute were measured at each station. Primary results reported 123 plant species belong to 46 families. Asteraceae and Lamiaceae were dominant families with 8 species each. PCORD version 5 were used for Cluster and Two Way Cluster Analyses that initiated 4 plant communities within elevation range of 529-700 m from sea level. Indicator species analyses (ISA) were used to identify indicator species of each community. CANOCO Software (version 4.5) was used to measure the influence of edaphic and topographic variables on species composition, diversity and community formation. Whereas Canonical Correspondence Analysis (CCA) was used to measure the effect of environmental variables which showed elevation and aspect were the stronger environmental variable among topographic and CaCO3 contents, electric conductivity, soil pH were the stronger edaphic factors in determination of vegetation and communities of the Bheer Hills. Grazing pressure was one of the main anthropogenic factors in this regard.

Introduction

The plant communities are a complex quantitative hierarchy in the vegetation science that always depends on species richness, distribution and associated ecological factors (Gaston, 2000, Maurer, 1999). These have previously been described floristically as well as physiognomically in number of ways. They have a demarcated structure in an area in relation to biotic and a biotic variation (Kent and Coker, 1992, Van Rooyen et al., 1981, Roberts and Wuest, 1999, Tainton et al., 1996, Cleaver et al., 2005, Brown and Bezuidenhout, 2005). Vegetation structure is usually influenced by environmental gradient and anthropogenic activates. In addition the edaphic and topographic factors also play a vital role in communities formation that ultimately leads to specific phytogeographic regions (Rohde, 1992). Ecological researches always tend to understand and quantify the relationship between biotic and a biotic components of an ecosystem (Tavili and Jafari, 2009). Various floristic analyses are used to identify the plant communities habitat types and important characteristic plant species (Katsuno, 1977, Fujiwara, 1987). In each sort of habitat each plant species has a microclimate and play its role in habitat formation (Duigan and Bredenkamp, 2003) and relations among populations (Scheiner, 1993). It is essential to measure and develop a suitable model to capture the natural features of an ecosystem for its sustainable use. Floristic analyses are the prerequisites for conservation of plant species. Therefore, current project was conducted to comprehend the role of such factor in the establishment of plant communities and its application in future conservation studies.

The Beer Hills along the Indus River have not been studied using recently developed analytical methods for vegetation characterization. The current study was therefore conducted to find out the floristic composition and vegetation structure of plant communities in the targeted region using modern tools. For this purpose plant species composition, abundance and the environmental variability, with special reference to gradient analyses were taken into consideration during 2012–2013.

Materials and methods

The Beer Hills are located at the bank of Indus River in two districts of Khyber Pakhtunkhwa province of Pakistan i.e., District Abbottabad and District Haripur at 34°10′ North latitude and 72°58′ East longitude with elevation 529–700 m at sea level. The temperature and precipitation equally distributed throughout the year with humid subtropical sort of climate. A total of seven transects were established at 3 km distance and within each transect five stations were recognized at 200 m interval randomly along with elevation gradient. In this a total of 34 stations with three hundred and six (306) quadrats were established using GPS (Global Positioning system) (Khan et al., 2013b). Quadrat and transect methods were used on hill slopes at all stations. Sizes of the quadrates for trees, shrubs and herbs were 10 × 5 m, 5 × 2 m and 1 × 1 m respectively (Salzer and Willoughby, 2004). Data attributes i.e., density, relative density, cover, relative cover, frequency, relative frequency and Importance Values Index (IVI) were measured at each station. The diameters of trees were measured at breast height (DBH) to find out its cover value for trees. The biological spectrum was determined using Raunkiaer Life form classification (Raunkiaer, 1934). The plant specimens were collected in each quadrat, labeled with tags, and pressed with plant presser in the field. Specimens were poisoned using 3% solution of Mercuric Chloride and Ethyl Alcohol solution and mounted on standard size herbarium sheets having a size of (17.5″ × 11.5″). All specimens were identified with the help of flora of Pakistan and other available literature (Khan et al., 2013a).

Soil analyses

The soil samples were collected up to 45 cm depth from each station through soil sampling tube. The samples were sieved to remove large particles. The soil physiochemical analyses i.e., Soil Texture, Calcium, Carbonate, Organic Matter concentration, Soil pH, Electrical Conductivity (E.C), Phosphorus and Potassium were measured in Agriculture research station Baffa Mansehra. The soil texture and pH were measured through hydrometer and pH meter respectively (Khan et al., 2012a, Khan et al., 2012b, Koehler et al., 1984). While, soil organic matters were determined by standardized solution of FeSO4 and K2Cr2O7 (Nelson et al., 1996). Whereas CaCO3 concentration were determined by acid neutralization method (Black et al., 1965). AB-DTPA extractable P and K was determined in samples through method described by Soltanpour (1991).

Data analyses

The data were statistically analyzed to find out the relationship between plant species composition and various ecological variables. For the data analysis we put the data of seven transect (34 stations and 306 quadrates) in MS EXCEL and prepared presence absence (1, 0) data sheet for CA (Cluster Analysis) and TWCA (Two Way Cluster Analysis). The plant species data were arranged horizontally and quadrates data were arranged vertically according to the software (PC-ORD version 5 software) requirement (Lepš and Šmilauer, 2003). The species and environmental data matrices were analyzed in CANOCO software version 4.5 to find the effect of environmental variables on species composition and distribution pattern.

Results

A research study was conducted in Beers Hills to find out plant species distribution pattern, composition and abundance in relation to environmental variables and edaphic factors.

Species composition of the Beer Hills

A total of 123 plant species were collected belong to 46 families distributed in 34 stations included 27 trees, 23 shrubs and 73 herbs species of all the vegetation. The topmost dominant families were Asteraceae and Lamiaceae having eight plant species, 13% of all species. The Amranathaceae, Moraceae and Poaceae have seven species each. While Malvaceae and Solanaceae with six species each respectively.

Raunkier life form

The plant species were classified through Raunkiaer (1934) classification into 5 various life form classes. The Phanerophytes was the most dominant class with 52 plant species (42%) followed by Therophytes with 37 species (30%), Hemicryptophytes with 24 species (20%), Cryptophytes with 7 species (6%) and Chemaephytes having 3 species (2%) respectively (Table 2).

Table 2

Plant species and Family names with Raunkiaer Life form classes.

NO. SO	Botanical name of Plants	Family name	Life forms
1	Acacia modista (Wall.)	Fabaceae	Ph
2	Acacia nilotica (L.)Del.	Fabaceae	Ph
3	Ailanthus altissima (Mill) Swingle	Simaroubaceae	Ph
4	Broussonetia papyrifera (L.) vent	Moraceae	Ph
5	Cassia fistula L.	Fabaceae	Ph
6	Ceiba pentandra (L.) Gaerth.	Malvaceae	Ph
7	Citrus aurantium L.	Rutaceae	Ph
8	Dalbergia sissoo Roxb.ex.DC.	Fabaceae	Ph
9	Eriobatrya japonica (Thunb.) lindl.	Rosaceae	Ph
10	Eucalyptus camaldulensis Dehnh.	Myrtaceae	Ph
11	Ficus benghalensis L.	Moraceae	Ph
12	Ficus carica L.	Moraceae	Ph
13	Ficus racemosa L.	Moraceae	Ph
14	Ficus religiosa L.	Moraceae	Ph
15	Juglans regia L.	Juglandaceae	Ph
16	Mallotus philippensis (Lam.) Muell.	Euphorbiaceae	Ph
17	Mangifera indica L.	Anacardiaceae	Ph
18	Melia azedarach L.	Meliaceae	Ph
19	Morus alba L.	Moraceae	Ph
20	Morus nigra L.	Moraceae	Ph
21	Olea ferruginea Royle.	Oleaceae	Ph
22	Papulus ciliata Wall.ex.Royle	Salicaceae	Ph
23	Pistacia integerrima J.L.Stewart ex Brandis	Anacardiaceae	Ph
24	Pterospermum acerifolium (L.) Willd.	Malvaceae	Ph
25	Punica granatum L.	Lythraceac	Ph
26	Syzygium cumini (L.) Skeels	Myrtaceae	Ph
27	Ziziphus jujuba Milli.	Rhamnaceae	Ph
28	Aerva javanica (Burm.f.)shult	Amaranthaceae	Ch
29	Berberis lycium Royle.	Berberidaceae	Ph
30	Calotropis procera (L.)	Asclapiadaceae	Ph
31	Colebrookea opposifolia Sm	Labiatae	Ph
32	Clerodendrum Philippinum multiplex.JPG	Verbenaceae	Ph
33	Carissa opaca L.	Apocynaceae	Ph
34	Cotoneaster dammeri C.K.Schneid.	Rosaceae	Ph
35	Dodonaea viscose (L.) Jacq.	Sapindaceae	Ph
36	Gymnosporia royleana Wall.	Celastraceae	Ph
37	Ipomoea carnea Jace.	Convolvulaceae	Cr
38	Jasminum nudiforum Lindl.	Oleaceae	Ph
39	Jasminum officinale L.	Oleaceae	Ph
40	Justicia adhatoda L.	Acanthaceae	Ph
41	Lantana camara L.	Verbenaceae	Ch
42	Marrubium supinum L.	Lamiaceae	Ph
43	Nerium oleander L.	Apocynaceae	Ph
44	Otostegia limbata (Beth.) Boiss	Lamiaceae	Ph
45	Parthenocissus semicordata Wall.	Vitaceae	Ph
46	Periploca aphylla Decne.	Asclepiadaceae	Ph
47	Ricinus communis L.	Euphorbiaceae	Ph
48	Rubus fruticosus L.	Rosaceae	Ph
49	Sageretia brendrethiana J.Linn.	Rhamnaceae	Ph
50	Woodfordia fruticosa (L.) Kurz	Lythraceac	Ph
51	Ziziphus nummularia Burm.f.	Rhamnaceae	Ph
52	Achyranthes asperaL.	Amaranthaceae	He
53	Adiantum caudatum Klotzsch	Pteridaceae	Th
54	Ajuga bracteosa Wall.	Lamiaceae	He
55	Alternanthera hirtula (Mart.)	Amaranthaceae	Th
56	Alternanthera philoxeroides Griseb.	Amaranthaceae	Th
57	Amaranthus spinosus L.	Amaranthaceae	Th
58	Amaranthus viridis L.	Amaranthaceae	Th
59	Anthriscus sylvestris L.	Apiaceae	Th
60	Argemone mexicana L.	Papaveraceae	Th
61	Artemisia absinthium L.	Asteraceae	Th
62	Arundo donax L.	Poaceae	Ph
63	Avena barbata Pott ex Link	Poaceae	Th
64	Barleria cristata L.	Acanthaceae	He
65	Bidens pilosa L.	Asteraceae	He
66	Brassica compestris L.	Brassicaceae	Th
67	Cannabis sativa L.	Cannabaceae	Th
68	Celosia argentea L.	Amaranthaceae	Th
69	Chenopodium album L.	Chenopodiaceae	He
70	Cichorium intybus L.	Asteraceae	Th
71	Commelina communis L.	Commelinaceae	Cr
72	Convolvulus arvensis L.	Convolvulaceae	Cr
73	Conyza bonariensis L.	Asteraceae	Th
74	Conyza canadensis (L.) Cronquist	Asteraceae	Th
75	Corchorus olitorius L.	Malvaceae	Th
76	Cynodon dactylon (L.)Pers.	Poaceae	He
77	Cynoglossum zeylanicum (Lehm.)Brand	Boraginaceae	He
78	Cyperus niveus Retz.	Cyperaceae	He
79	Cyperus rotundus L.	Cyperaceae	He
80	Datura alba L.	Solanaceae	Th
81	Debregeasia salicifolia N/A	Urticaceae	Ph
82	Delphinium bicolor Nutt.	Ranunculaceae	Th
83	Diclipter roxburghiana T.Anders.	Acanthaceae	Th
84	Echinochloa colona (L.) link.	Poaceae	He
85	Euphorbia helerophylla L.	Euphorbiaceae	Th
86	Euphorbia helioscopia L.	Euphorbiaceae	Th
87	Euphorbia hirta L.	Euphorbiaceae	Th
88	Hybiscus caesius Garcke var caesius	Malvaceae	Ph
89	Ipomoea hederacea Jaeq.	Convolvulaceae	Cr
90	Ipomoea purpurea (L.) Rath	Convolvulaceae	Cr
91	Lepidium virginicum L.	Brassicaceae	He
92	Leucas cephalota (Roth) Spreng.	Lamiaceae	Th
93	Malva neglecta Wallr.	Malvaceae	He
94	Malvastrum coromandelianum L.	Malvaceae	He
95	Marsilea villosa Kanlf.	Marsileaceae	Cr
96	Medico denculatus L.	Fabaceae	He
97	Melica persica Kunth	Poaceae	He
98	Mentha longiafolia (L.) Huds.	Lamiaceae	He
99	Mentha piperita L.	Lamiaceae	He
100	Mirabilis jalapa L.	Nyctaginaceae	Th
101	Nasturtium officinale W.T.Aiton	Brassicaceae	Th
102	Oxalis corniculata L.	Oxalidaceae	He
103	Oxalis corymbosa DC.	Oxalidaceae	He
104	Parthenium hysterophorus L.	Asteraceae	He
105	Pastinaca sativa L.	Apiaceae	Th
106	Pentanema indicum (L.)Ling	Asteraceae	Th
107	Persicaria globra Willd.	Polygonaceae	Th
108	Phegopteris connectilis (Michx.) Wall	Thelypteridaceae	Cr
109	Physalis angulata L.	Solanaceae	Ph
110	Polygonum aviculare L.	Polygonaceae	He
111	Ranunculus muricatus L.	Ranunculaceae	He
112	Rumex dentatus L.	Polygonaceae	He
113	Salvia coccinea Buc.	Lamiaceae	Th
114	Solanum nigrum L.	Solanaceae	Th
115	Solanum pseudocapsicum L.	Solanaceae	Th
116	Solanum surattense L.	Solanaceae	Th
117	Solanum virginanum L.	Solanaceae	Th
118	Sorghum vulgare L.	Poaceae	Th
119	Triticum aestivum L.	Poaceae	Th
120	Urtica dioica L.	Urticaceae	Th
121	Vaccaria pyramidata Medik.	Caryophyllaceae	Th
122	Verbascum thapsus L.	Scrophulariaceae	He
123	Xanthium strumarium L.	Asteraceae	Ch

Ph = Phanerophyte; Ch = Chamaephytes; He = Hemicryptophytes; Cr = Cryptophytes; Th = Therophytes.

Abundant and less abundant plant species of the Beer Hills

The abundant and less abundant plant species were found on the basis of Importance Values Index (IVI). The topmost abundant tree species of the study area was Mallotus philippensis, Acacia nilotica, Acacia modista, Ziziphus jujuba, Ficus benghalensis, Ficus carica, Broussonetia papyrifera, Pistacia integerrima, Dalbergia sissoo and Morus nigra with high IVI. While Punica granatum, Ailanthus altissima, Citrus aurantium, Pterospermum acerifolium, Eriobatrya japonica, Ceiba pentandra, Cassia fistula, Syzygium cumimi, Juglans regia, and Ficus religiosa were recorded as less abundant trees with minimum IVI in the study area. In shruby layer the most dominant species were Dodonaea viscosa, Justicia adhatoda, Otostegia limbata, Berberis lyceum, Cotoneaster dammeri, Sageretia brendrethiana, Ziziphus nummularia, Marrubium supinum, Nerium oleander and Periploca aphylla with IVI above than 800 in the region. The top ten rare shrub species were Lantana camara, Ipomoea carnea, Clerodendrum philippinum, Parthenocissus semicordata, Rubus fruticosa, Aera javanica, Ricinus communis, Jasminum nudiforum, Jasminum officinale and Calotropis procera having low Importance values in the Beer Hills along with Indus River. In addition to, the Cynodon dactylon, Avena barbata, Medicogo denculatus, Parthenium hysterophorus, Cannabis sativa, Euphorbia helioscopia, Euphorbia hirta, Nasturtium officinale, Malva neglecta, and Melica persica were the most abundant species in herbaceous layer of the region. The uppermost rare herbs recorded with minimum IVI were Datura alba, Brassica compestris, Alternanthera philoxeroides, Physalis angulate, Phegoteris connectilies, Achyranthes aspera, Diclipter roxburghiana, Cypres routundes, Oxalis corniculata and Cyprus niveus. Most of the rare species present in the area were palatable which faces great pressure of grazing.

Species area curve

Initially PC-ORD version 5 were used to draw species area curves and compositional area curves to recognize either the quadrates size was adequate or not through abundance data combined with Sorensen distance values (Ahmad et al., 2016a, Ahmad et al., 2016b). It also comprehends the vegetation relation with environmental variables. It results that the transect number 25 show maximum number of plant species and appearing new species continuously up to station number 31 (Fig. 1).

Fig. 1

The Specie area curves showing adequacy of sampling in the studied area.

Results of Cluster Analysis

The Cluster Analyses using PCORD version 5 clustered 34 stations (306 quadrats) into 4 plant communities or habitats (Fig. 2).

Fig. 2

Cluster dendrogram classified 34 sampled stations into 4 habitat types/plant communities.

Two Way Cluster Analysis (TWCA)

The Two Way Cluster analysis showed distribution of plant species in sampling stations. It was constructed with the help of presence and absence (1, 0) data sheet by Soresen measures. The black bubbles/dots represented the presence whereas white bubbles indicated the absence of plant species in the region. Four plant communities were recognized through grouping of various stations (Fig. 3).

Fig. 3

Two Way Cluster dendogram showing distribution of 123 species in 306 quadrats.

Classification of plant communities

Ficus beghalensis-Nerium oleander-Euphorbia heterophylla community

The community name was given based on Indicator species analyses (ISA). This community was observed at elevation of 432–583 m. Ficus beghalensis, Nerium oleander and Euphorbia heterophylla were the characteristics species of tree, shrub and herb layer respectively. The other dominant species of tree layer with high IVI values included Mallotus philippensis, Broussonetia papyrifera, Ficus carica, Dalbergia sissoo and Mangifera indica. While the rare tree species were Ceiba pentandra, Cassia fistula, Syzgium cumini, Juglans regia, Ficus religiosa and Olea ferruginea with minimum IVI in the region. Whereas shrub layer was dominated by Justicia adhatoda, Otostegia limbata, Nerium oleander, Dodonaea viscosa, Cotoneaster dammeri, Marrubium supinum, with rare species Carissa opaca, Sageretia brendrethiana, Jasminum nudiforum, Ricinas comununis, Jasminum officinale, Calotropis procera. Although the dominant herbaceous layer included Cynodon dactylon, Cannabis sativa, Avena barbata, Nasturtium officinale, Parthenium hysterophorus, Euphorbia helioscopia, Mediogo denculatus, Malva neglecta, Euphorbia heterophylla and Rumex dentatus. Whereas Physalia angulata, Hybisus caesium, Phegopteris connectilis, Achyranthes aspera, Delphinium bicolar, Dicolipter roxburghiana, Argemome Mexicana, Artemisia absinthium and oxalis corymbosa are rare herbs species in the region with low IVI values.

The characteristic plant species in community i.e., Ficus beghalensis having important value 78 and p value 0.02, Euphorbia helerophylla having IVI 71 and with p value 0.03. In addition to the data attribute plot of Ficus beghalensis that show the grazing pressure has no effect on this species because tree layer was not affected by grazing pressure but greatly affected by high altitude as a result it was mostly observed in lower altitude of the region. While the electrical conductivity of community soil was measured between 0.16 and 0.25 dsm−1, Calcium carbonate was 2.4–6.2%, Potassium 90–130 ppm and Phosphorus 5.6–8.4 ppm respectively.

Ficus carica - Justicia adhatoda - Parthinium hysterophorus community

This community was found between elevations of 557–640 m. The Ficus carica, Justicia adhatoda, and Parthinium hysterophorus were the dominant characteristic tree, shrub and herb. The other dominant species of the tree layer included Acacia nilotica, Acacia modista, Ziziphus jujuba, Olea ferruginea and Ficus carica. While, the rare tree species were Punica granatum, Broussonetia papyriafera, Melia azedarach, Morus nigra and Dalbergia sissoo. Regarding the shruby layer Dodonia viscosa, Justicia adhatoda, Otostegia limbata, Sageretia brenrerthiana, Colebrookea opposifolia was the most dominant and Marrubium supinum, Gymnosporia royleane, Cotoneaster dammeri, Ricinus communis and Calotropis procera was the rare plant species in the region. The characteristic species of herbaceous layer was Cynodon dactylon, Solanum surattense, Parthenium hysterophous, Medicogo denculatus, Avena barbata, Euphorbia hirta, Euphorbia helioscopia, Rumex dentatus, Delphinium bicolor, Amaranthus viridis and the characteristic rare species of community was Mirabilis jalapa, Convolvulus arvensis, Solanum pseudocapsium, Bidens pilosa, Conyza Canadensis, Ranunculus muricatus, Cichorium intybus, Achyranthus aspera, Phegopteris connectilis and Physalis angulate with minimum IVI.

Regarding the soil analyses of community electrical conductivity was 0.15–0.25 dsm−1, Calcium carbonate was 5.2–7.2%, Potassium was 100–125 ppm and Phosphorus 6.4–7.5 ppm was recorded.

Melia azedarach - Dodonaea viscosa – Polygonum avicula community

This community was found at the elevation of 572–645 m. The recorded Characteristic species of tree layer was Mallotus philippensis, Pistacia integerrima, Acacia modista, Ziziphus jujuba and Acacia nilotica. While rare trees were Olea ferruginea, Broussonetia papyrifera, Ficus racemosa, Morus alba and Melia azedarach with minimum IVI in the region. While, the dominant species of shruby vegetation in community included Dodonaea viscosa, Berberis lyceum, Otostegia limbata, Carissa opaca and Sageretia brendrethiana. In addition to, Periploca aphylla, Gymnosporia royleana, Aerva javanica, Marrubium supinum, Polygonum avicular and Colebrookea opposifolia was the rare shrubs recorded with low IVI in the region. The characteristic herbaceous species are Avena barbata, Melica persica, Medicogo denculatus, Artemisia absinthium, Parthenium hysterophous, Argemone Mexicana, Euphorbia hirta, Euphorbia helioscopia and Polygonum aviculare. The community has rare herb species with minimum IVI was Ajuga bracteosa, Malva neglecta, Arundo donax, Hybiscus caesius, Vaccaria pyramidata, Urtica dioica, Ipomoea hederacea, Ipomoea purpurea, Physalis angulata and Solanum virginanum.

The soil analyses resulted that the community has Electrical conductivity between 0.17 and 0.23 dsm−1, Calcium carbonate 2.4 and 6.5%, Potassium 100 and 130 ppm and Phosphorus 7.3 and 8.2 ppm respectively.

Acacia nilotica - Berberis lycium - Echinochloa colona community

This community initiated at the elevation of 2485–2937 m. The dominant tree species were Acacia modista, Ziziphus jujuba, Mallotus philippensis with rare species Morus nigra, Ficus carica and Broussonetia papyrifera. The characteristic shrub species of the community were Indigofera heterantha and Plectranthus rugosus. While dominant species were Berberis lycium, Dodonaea viscosa, Periploca aphylla, Justicia adhatoda, Ziziphus nummularia and rare species included Cotoneaster dammeri, Sageretia brendrethiana, Carissa opaca and Gymnosporia royleana. Among the characteristic herbaceous species Cynodon dactylon, Avena barbata, Euphorbia hirta, Mediocogo denculatus, Delphinium bicolor, Melica persica, Conyza bonariensis, Conyza Canadensis, Echinochloa colona and Solanum surattens. Whereas Argemone mexicaca, Parthenium hysterophorous, Saliva coccinea, Chenopodium album, Leucas cephalota, Ajuga bracteosa, Barleria cristata, Sorghum vulgare, Oxalis corniculata, and Xanthium strumarium were recorded as rare herbs with minimum IVI in the region.

The soil analyses of this habitat show the electrical conductivity between 0.16 and 0.22 dsm−1, Calcium carbonate 4 and 6.4%, Potassium 100 and 130 ppm and Phosphorus 6 and 9 pp, which play a significant key role in distribution of plant species of present community.

Environmental gradient

The Species and environmental data matrices were put together in CANOCO software version 4.5. All environmental variables as biotic factors (grazing pressure) and abiotic factors (edaphic and topographic) show significant effect on plant species composition, distribution pattern and abundance with p value (p ≤ 0.002) (Table 1).

Table 1

Data summary table of 123 plant species in relations with all he environmental variables.

Axis	1	2	3	4	TI
EV (eigen values)	0.363	0.165	0.105	0.096	2.216
SEC (species-environment correlations)	0.962	0.910	0.906	0.915
CPVSP (cumulative percentage variance of species data)	16.4	23.8	28.6	32.9
SER (species-environment relation)	33.0	47.9	57.5	66.2
SMC test
TSFCA (test of significance of first canonical axis)		TSACA (test of significance of all canonical axes)
EV (eigen value)	0.363	(Trace)			1.102
FR (F-ratio)	4.121	FR (F-ratio)			1.730
PV (P-value)	0.0020	PV (P-value)			0.0020

In ordination of various plant species each cross in the figure represented a plant species and the distance between them show the similarity and differences index. All the plant species were compared with environmental gradient and soil data through CANOCO software. The treated environmental variables were altitude, aspect, grazing pressure, organic matter, phosphorous, potassium, pH, deep soil, silt and rocky soil. The CCA (bi-plot diagram) of first quadrant indicated most of the plants were assembled under the influence of CaCO3 and sandy nature of soil. While going through 3rd quadrant most of the environmental variables clustered around phosphorous, pH, organic matter concentration, potassium, high elevation rang and clay nature of soil. Furthermore on the 4th quadrant most of the plants are assembled under the influence of electrical conductivity and grazing pressure (Fig. 4).

Fig. 4

CCA diagram showing the species distribution under the influence of various environmental variables. Spp = Species, Env Var = Environmental factors, Phosph = Phosphorus, Potas = Potassium, Elec Con = Electrical Conductivity, Organ M = Organic Matter, Text Cla = Texture Class, Graz Pr = Grazing Pressure.

Ordination of different stations under the influence of environmental gradient

The CCA ordination bi-plot based on edaphic and topographic factors data presents the first quadrant was preliminary related with CoCO3 and sandy nature of soil (Fig. 5). The 3rd quadrants was mainly correlated with phosphorous, pH, organic matter concentration, potassium, high elevation rang and clay nature of soil having T2S2, T3S2, T4S2, T5S, T5S4, T6S2 and T6S3 (T = transect, S = station). While the 4rt quadrant show aspect of electrical conductivity and grazing pressure that clustered T4S1, T5S1, T5S2, T6S1 and T7S1 respectively (Fig. 5).

Fig. 5

CCA bi-plot diagram showing the distribution of sampled stations in relation to various environmental variables. T = Transect, S = Station, Samp = Sample, Env Var = Environmental factors, Phosph = Phosphorus, Potas = Potassium, Elec Con = Electrical Conductivity, Organ M = Organic Matter, Text Cla = Texture Class, Graz Pr = Grazing Pressure.

Discussion

The current study revealed a total of 123 plant species of the Beer Hills along Indus River belong to 46 families. The 27 tree species (22%), 23 shrubs (19%) and 73 herbs (59%) were recorded. The study area revealed the herb species were in maximum number with greater cover, followed by trees and shrubs. Physiographic factors such as slope angle, different edaphic factors and altitudinal rang effect the vegetation composition and distribution pattern. Furthermore, at higher altitude vegetation layer became decrease due to physical and biological factors that affect plant growth. The same results were reported by Haq et al. (2011) that showed the vegetation was rich at lower elevation as compared to higher elevation range. The flora of Beer Hills result Asteraceae, Lamiaceae, Moraceae, Amaranthaceae and Poaceae was the most dominant families of the region. Similarly Asteraceae and Lamiaceae were proved well established and largest families in flora of Pakistan by Ali and Qaiser, 1995, Stewart, 1972. Plus in other adjacent locations Dar et al., 2012 reported one hundred and three families at Machiara national park Muzaffarabad. The dominant families of the investigated area were Balsaminaceae, Ranunculaceae and Asclepiadaceae. While Pant and Samant (2007) described forest plant biodiversity of the Western Himalaya. Similar to our results Perveen and Hussain (2007) work out on species density, cover and frequency of Gorakh hills and reported seventy-four plant species distributed in thirty-four families. Plants play a vital role in economy of a country. It was used as food, fruit, medicines, forage, timber wood, fire wood, etc. (Durrani, 2000, Malik, 2005, Shinwari et al., 1996). This research project also resulted various plant species i.e., Medicogo denculatud, Malva neglecta were edible species, Mentha species, Justicia adhatoda and Acacia were medicinally use, Morus species, Melia azedarach were used as a timber and Dadonia vescosa were used as a fuel wood in the Beer Hills area. Flora of an area represents the particular species of an area which are qualitatively and quantitatively analyzed. Floristic structure of a region was very important to relate it with environmental gradient. It depends upon biotic and abiotic factors of an environment and can be affected by deforestation and over grazing particularly (Longhi et al., 1992). Similar were also reported in present work that grazing pressure effect on plant species distribution and composition. A total of 4 plant communities were identified through PCORD version 5 in study area. (Moinuddin et al., 2006: Ahmad et al., 2016a) studied the Phyto-sociological analysis of Himalayan forests of Pakistan, described twenty-four different communities and four monophonic specific forests vegetation as well as labeled the species composition and IVI values. While CANOCO Software version 4.5 was used to measure the influence of edaphic and topographic variables on species composition and diversity and community formation. Similar techniques were also applied by Khan et al. (2012b) for proper documentation of plant species. Whereas Borcard et al., 1992 performed Canonical Correspondence Analysis (CCA) by using a quantitative statistical approach to categorize among various variables. Brown and Bezuidenhout (2005) investigated National park (De mountain zebra National park, South Africa) and find out fourteen communities consuming TWINSPAN grouping. The soil pH ranges from 7.2 to 7.8; organic matter concentration from 0.52% to 0.85%, calcium carbonate amount is 2.38% to 7.2%, sand concentration was 28.6% to 58.6%, Phosphorous was 5.6 ppm to 9 ppm, potassium ranges 130 ppm to 90 ppm. Similarly (Khan et al., 2012a, Khan et al., 2012b, Khan et al., 2014, Khan et al., 2016, Nazir et al., 2012, Shaheen et al., 2011, Iqbal et al., 2015, Ahmad et al., 2016a) also found out various plant communities in relation to environmental gradients. Furthermore, Noureen et al., 2008 investigated Cholistan desert, vegetation on the basis of environmental factors. Whereas, Yimer, 2007, defined that soil disturb the structure of the plant community and ground cover, amount of plant development, capability of natural regeneration and additional critical factors. In study area grazing pressure was observed higher at lower elevation range of the Beer Hills. It was also reported by Pennings and Silliman (2005) that grazing pressure was high at lower elevation. Whereas, Sakya and Bania (1998) describes, elevation play an important role in the community formation. Shank and Noorie (1950) find out that temperature and atmospheric pressure changed with increasing height other factors like soil pH, soil moisture, soil nutrients and biotic factors also take part in the formation of plant communities. Life forms of the plants were very important to describe the vegetation structure. The plant species collected in the study area were classified into five Raunkiaer classes. It was resulted that Phanerophytes was the dominant class followed by the Therophytes, Hiemicryptophytes, Cryptophytes, and Chamaephytes respectively. A similar result was described by Malik and Malik (2004) in Kotli Hill Kashmir. Whereas Hadi et al. (2009) reported a phytosociological effort on weed flora in the vegetable fields of (Botanical Garden, Azakhel in summer season 2009) which consist of 30 weed species in different vegetables fields with dominant Therophytes life form class.

Conclusion

It was concluded that CaCO3 contents, electrical conductivity, soil pH, organic matter concentration, phosphorous and silty nature of soil were the stronger edaphic factors. While, among topographic factor the elevation and aspect were the significant environmental variables that affect the distribution pattern, composition and diversity of plant species and communities of Beer Hills. Identification of indicator and rare plant species in the specific micro-habitat can further be used for conservation management purposes.

Appendix A

Importance value index (IVI) of each plant species in the studied area.

No. S	Plant name		Plant name		Plant name		Plant name
	Plant name	T IVI 1		T IVI 2	Plant name	T IVI 3	Plant name	T IVI 4
1	Ficus benghalensis	279.9	Acacia nilotica	173.8	Mallotus philippensis	286.9	Acacia modista	68.8
2	Mallotus philippensis	263.2	Acacia modista	123.3	Pistacia integerrima	151.8	Ziziphus jujuba	62.2
3	Broussonetia papyrifera	208.2	Ziziphus jujube	96.6	Acacia modista	69.5	Mallotus philippensis	61.4
4	Ficus carica	181.5	Olea ferruginea	67	Ziziphus jujube	69.2	Acacia nilotica	52.3
5	Dalbergia sissoo	179.7	Ficus carica	32.4	Acacia nilotica	68.8	Morus nigra	24.6
6	Mangifera indica	165.3	Mallotus philippensis	32	Ficus carica	57.4	Ficus carica	14.3
7	Ziziphus jujube	129	Punica granatum	29	Morus nigra	38.8	Broussonetia papyrifera	6.2
8	Eucalyptus camaldulensis	125	Broussonetia papyrifera	12	Olea ferruginea	37.8	Ailanthus altissima	0
9	Morus alba	121.7	Melia azedarach	12	Broussonetia papyrifera	27.7	Cassia fistula	0
10	Acacia modista	121.4	Morus nigra	9.9	Ficus racemosa	6	Ceiba pentandra	0
11	Morus nigra	119.9	Dalbergia sissoo	9	Morus alba	4.6	Citrus aurantium	0
12	Ficus racemosa	115.5	Ailanthus altissima	0	Melia azedarach	3.8	Dalbergia sissoo	0
13	Populus ciliata	112.6	Cassia fistula	0	Ailanthus altissima	0	Eriobatrya japonica	0
14	Acacia nilotica	108.5	Ceiba pentandra	0	Cassia fistula	0	Eucalyptus camaldulensis	0
15	Melia azedarach	95.4	Citrus aurantium	0	Ceiba pentandra	0	Ficus benghalensis	0
16	Ailanthus altissima	62.1	Eriobatrya japonica	0	Citrus aurantium	0	Ficus racemosa	0
17	Punica granatum	58.9	Eucalyptus camaldulensis	0	Dalbergia sissoo	0	Ficus religiosa	0
18	Pistacia integerrima	56.4	Ficus benghalensis	0	Eriobatrya japonica	0	Juglans regia	0
19	Citrus aurantium	55	Ficus racemosa	0	Eucalyptus camaldulensis	0	Mangifera indica	0
20	Pterospermum acerifolium	34.1	Ficus religiosa	0	Ficus benghalensis	0	Melia azedarach	0
21	Eriobatrya japonica	30	Juglans regia	0	Ficus religiosa	0	Morus alba	0
22	Ceiba pentandra	29.9	Mangifera indica	0	Juglans regia	0	Olea ferruginea	0
23	Cassia fistula	25.6	Morus alba	0	Mangifera indica	0	Populus ciliata	0
24	Syzygium cumini	22.5	Populus ciliata	0	Populus ciliata	0	Pistacia integerrima	0
25	Juglans regia	17.3	Pistacia integerrima	0	Pterospermum acerifolium	0	Pterospermum acerifolium	0
26	Ficus religiosa	15.4	Pterospermum acerifolium	0	Punica granatum	0	Punica granatum	0
27	Olea ferruginea	14.8	Syzygium cumini	0	Syzygium cumini	0	Syzygium cumini	0
28	Justicia adhatoda	259.1	Dodonaea viscosa	194.15	Dodonaea viscosa	366.8	Berberis lycium	140.6
29	Otostegia limbata	198.7	Justicia adhatoda	190.55	Berberis lyceum	185.3	Dodonaea viscosa	133.9
30	Nerium oleander	179	Otostegia limbata	94.4	Otostegia limbata	162.5	Periploca aphylla	104.4
31	Dodonaea viscosa	174.6	Sageretia brendrethiana	85.5	Carissa opaca	117.8	Justicia adhatoda	89.5
32	Cotoneaster dammeri	167.7	Colebrookea opposifolia	29	Sageretia brendrethiana	93.3	Ziziphus nummularia	48.1
33	Marrubium supinum	161	Ziziphus nummularia	14.4	Cotoneaster dammeri	87	Cotoneaster dammeri	30.6
34	Colebrookea opposifolia	112.9	Marrubium supinum	13	Justicia adhatoda	72.2	Sageretia brendrethiana	26.2
35	Ziziphus nummularia	86.9	Gymnosporia royleana	12	Ziziphus nummularia	70.5	Otostegia limbata	25
36	Woodfordia fruticosa	86.3	Cotoneaster dammeri	11.6	Periploca aphylla	58.6	Carissa opaca	15
37	Gymnosporia royleana	79.3	Ricinus communis	1.4	Gymnosporia royleana	57.1	Gymnosporia royleana	13.7
38	Lantana camara	76.05	Calotropis procera	1.03	Aerva javanica	28.4	Aerva javanica	0
39	Ipomoea carnea	75.15	Aerva javanica	0	Marrubium supinum	28	Calotropis procera	0
40	Berberis lyceum	75	Berberis lyceum	0	Colebrookea opposifolia	17.3	Clerodendrum Philippinum	0
41	Clerodendrum Philippinum	62.79	Carissa opaca	0	Calotropis procera	0	Colebrookea opposifolia	0
42	Parthenocissus semicordata	62	Clerodendrum Philippinum	0	Clerodendrum Philippinum	0	Ipomoea carnea	0
43	Rubus fruticosus	53	Ipomoea carnea	0	Ipomoea carnea	0	Jasminum nudiforum	0
44	Carissa opaca	28.9	Jasminum nudiforum	0	Jasminum nudiforum	0	Jasminum officinale	0
45	Sageretia brendrethiana	23.9	Jasminum officinale	0	Jasminum officinale	0	Lantana camara	0
46	Jasminum nudiforum	17	Lantana camara	0	Lantana camara	0	Marrubium supinum	0
47	Ricinus communis	16.1	Nerium oleander	0	Nerium oleander	0	Nerium oleander	0
48	Jasminum officinale	14.1	Parthenocissus semicordata	0	Parthenocissus semicordata	0	Parthenocissus semicordata	0
49	Calotropis procera	8.75	Periploca aphylla	0	Ricinus communis	0	Ricinus communis	0
50	Aerva javanica	0	Rubus fruticosus	0	Rubus fruticosus	0	Rubus fruticosus	0
51	Periploca aphylla	0	Woodfordia fruticosa	0	Woodfordia fruticosa	0	Woodfordia fruticosa	0
52	Cynodon dactylon	1145	Cynodon dactylon	302	Cynodon dactylon	525	Cynodon dactylon	560
53	Cannabis sativa	800	Solanum surattense	220	Avena barbata	264	Avena barbata	198
54	Avena barbata	651	Parthenium hysterophorus	215	Melica persica	221	Euphorbia hirta	190
55	Nasturtium officinale	646	Medicogo denculatus	203	Medicogo denculatus	202	Medicogo denculatus	160
56	Parthenium hysterophorus	643	Avena barbata	187	Artemisia absinthium	190	Delphinium bicolor	149
57	Euphorbia helioscopia	640	Euphorbia hirta	93	Parthenium hysterophorus	168	Melica persica	145
58	Medicogo denculatus	605	Euphorbia helioscopia	74	Argemone mexicana	159	Conyza bonariensis	125
59	Malva neglecta	574	Rumex dentatus	73	Euphorbia hirta	144	Conyza canadensis	111
60	Euphorbia helerophylla	548	Delphinium bicolor	67	Euphorbia helioscopia	127	Echinochloa colona	92
61	Rumex dentatus	434	Amaranthus viridis	64	Polygonum aviculare	121	Solanum surattense	92
62	Mentha piperita	428	Ajuga bracteosa	55	Salvia coccinea	121	Polygonum aviculare	79
63	Xanthium strumarium	414	Alternanthera hirtula	51	Solanum surattense	121	Hybiscus caesius	68
64	Persicaria globra	385	Adiantum caudatum	46.05	Lepidium virginicum	115	Argemone mexicana	62
65	Amaranthus viridis	322	Oxalis corniculata	45	Barleria cristata	113	Parthenium hysterophorus	62
66	Euphorbia hirta	316	Malvastrum coromandelianum	44	Alternanthera hirtula	103	Salvia coccinea	60
67	Sorghum vulgare	316	Verbascum Thapsus	44	Xanthium strumarium	102	Chenopodium album	59
68	Mentha longiafolia	300	Cyperus rotundus	43	Bidens pilosa	96	Leucas cephalota	57
69	Melica persica	263	Arundo donax	36	Cannabis sativa	72	Ajuga bracteosa	54
70	Celosia argentea	259	Chenopodium album	32	Conyza canadensis	71	Barleria cristata	36
71	Cichorium intybus	258	Argemone mexicana	30	Conyza bonariensis	67	Sorghum vulgare	34
72	Mirabilis jalapa	244	Cannabis sativa	30	Delphinium bicolor	64	Oxalis corniculata	32
73	Conyza canadensis	227	Cyperus niveus	21	Amaranthus spinosus	62	Xanthium strumarium	30
74	Arundo donax	220	Solanum nigrum	19	Rumex dentatus	62	Achyranthes aspera	0
75	Bidens pilosa	211	Malva neglecta	18	Pentanema indicum	58	Adiantum caudatum	0
76	Commelina communis	211	Mirabilis jalapa	18	Cichorium intybus	55	Alternanthera hirtula	0
77	Solanum nigrum	208	Convolvulus arvensis	16	Malvastrum coromandelianum	55	Alternanthera philoxeroides	0
78	Chenopodium album	202	Solanum pseudocapsicum	15	Leucas cephalota	49	Amaranthus spinosus	0
79	Ranunculus muricatus	202	Bidens pilosa	13	Chenopodium album	46	Amaranthus viridis	0
80	Pastinaca sativa	196	Conyza Canadensis	13	Echinochloa colona	43	Anthriscus sylvestris	0
81	Echinochloa colona	182	Ranunculus muricatus	8	Verbascum thapsus	39	Artemisia absinthium	0
82	Anthriscus sylvestris	160	Cichorium intybus	7	Ajuga bracteosa	38.08	Arundo donax	0
83	Lepidium virginicum	160	Achyranthes aspera	6.05	Malva neglecta	37	Bidens pilosa	0
84	Leucas cephalota	157	Phegopteris connectilis	6	Arundo donax	34	Brassica compestris	0
85	Amaranthus spinosus	155	Physalis angulata	1	Hybiscus caesius	34	Cannabis sativa	0
86	Malvastrum coromandelianum	153	Alternanthera philoxeroides	0	Vaccaria pyramidata	29	Celosia argentea	0
87	Verbascum thapsus	149	Amaranthus spinosus	0	Urtica dioica	10	Cichorium intybus	0
88	Corchorus olitorius	145	Anthriscus sylvestris	0	Ipomoea hederacea	6	Commelina communis	0
89	Oxalis corniculata	140	Artemisia absinthium	0	Ipomoea purpurea	6	Convolvulus arvensis	0
90	Solanum virginanum	130	Barleria cristata	0	Physalis angulata	1	Corchorus olitorius	0
91	Vaccaria pyramidata	128	Brassica compestris	0	Solanum virginanum	1	Cynoglossum zeylanicum	0
92	Urtica dioica	121	Celosia argentea	0	Achyranthes aspera	0	Cyperus niveus	0
93	Alternanthera hirtula	120	Commelina communis	0	Adiantum caudatum	0	Cyperus rotundus	0
94	Marsilea villosa	118	Conyza bonariensis	0	Alternanthera philoxeroides	0	Datura alba	0
95	Debregeasia salicifolia	110.3	Corchorus olitorius	0	Amaranthus viridis	0	Debregeasia salicifolia	0
96	Triticum aestivum	108	Cynoglossum zeylanicum	0	Anthriscus sylvestris	0	Diclipter roxburghiana	0
97	Adiantum caudatum	107.65	Datura alba	0	Brassica compestris	0	Euphorbia helerophylla	0
98	Convolvulus arvensis	106	Debregeasia salicifolia	0	Celosia argentea	0	Euphorbia helioscopia	0
99	Cynoglossum zeylanicum	103	Diclipter roxburghiana	0	Commelina communis	0	Ipomoea hederacea	0
100	Pentanema indicum	100	Echinochloa colona	0	Convolvulus arvensis	0	Ipomoea purpurea	0
101	Solanum pseudocapsicum	99	Euphorbia helerophylla	0	Corchorus olitorius	0	Lepidium virginicum	0
102	Solanum surattense	99	Hybiscus caesius	0	Cynoglossum zeylanicum	0	Malva neglecta	0
103	Ipomoea hederacea	93	Ipomoea hederacea	0	Cyperus niveus	0	Malvastrum coromandelianum	0
104	Ipomoea purpurea	93	Ipomoea purpurea	0	Cyperus rotundus	0	Marsilea villosa	0
105	Ajuga bracteosa	87	Lepidium virginicum	0	Datura alba	0	Mentha longiafolia	0
106	Datura alba	85	Leucas cephalota	0	Debregeasia salicifolia	0	Mentha piperita	0
107	Polygonum aviculare	82	Marsilea villosa	0	Diclipter roxburghiana	0	Mirabilis jalapa	0
108	Barleria cristata	80	Melica persica	0	Euphorbia helerophylla	0	Nasturtium officinale	0
109	Brassica compestris	79	Mentha longiafolia	0	Marsilea villosa	0	Oxalis corymbosa	0
110	Alternanthera philoxeroides	78	Mentha piperita	0	Mentha longiafolia	0	Pastinaca sativa	0
111	Conyza bonariensis	76	Nasturtium officinale	0	Mentha piperita	0	Pentanema indicum	0
112	Physalis angulata	72	Oxalis corymbosa	0	Mirabilis jalapa	0	Persicaria globra	0
113	Hybiscus caesius	71	Pastinaca sativa	0	Nasturtium officinale	0	Phegopteris connectilis	0
114	Salvia coccinea	60	Pentanema indicum	0	Oxalis corniculata	0	Physalis angulata	0
115	Phegopteris connectilis	59	Persicaria globra	0	Oxalis corymbosa	0	Ranunculus muricatus	0
116	Achyranthes aspera	57.83	Polygonum aviculare	0	Pastinaca sativa	0	Rumex dentatus	0
117	Delphinium bicolor	57	Salvia coccinea	0	Persicaria globra	0	Solanum nigrum	0
118	Diclipter roxburghiana	52	Solanum virginanum	0	Phegopteris connectilis	0	Solanum pseudocapsicum	0
119	Argemone mexicana	50	Sorghum vulgare	0	Ranunculus muricatus	0	Solanum virginanum	0
120	Artemisia absinthium	43	Triticum aestivum	0	Solanum nigrum	0	Triticum aestivum	0
121	Oxalis corymbosa	30	Urtica dioica	0	Solanum pseudocapsicum	0	Urtica dioica	0
122	Cyperus niveus	0	Vaccaria pyramidata	0	Sorghum vulgare	0	Vaccaria pyramidata	0
123	Cyperus rotundus	0	Xanthium strumarium	0	Triticum aestivum	0	Verbascum thapsus	0