Some phytogeographic aspects of Rajasthan,India

Summary The literature on the demarcation line between the Indo-Malayan and the Perso-Arabian floras is reviewed and it is proposed to base the delimitation on the vegetation types. In the forests of teak or miscellaneous species generally located on the hills, the Indo-Malayan and the Indian elements predominate but in the thicket or scattered shrubby vegetation ofProsopis, Salvadora, Acacia, Capparis, Euphorbia of the sandy alluvial plains of North Gujarat and Rajasthan the western element is conspicuous.Geologically, Rajasthan west of the Aravallis possesses a mingling of the distinctive characters of the Peninsula and the extra-Peninsula and cannot be referred to as either. It is shown that plantgeography does not provide any evidence to consider the area as probably peninsular as suggested previously.     

Rotifer fauna in the periphyton of Karst rivers in Croatia,Yugoslavia

Rotifers from periphyton communities of rivers in the Karst area of western Yugoslavia were examined. Thirty-two species, belonging to 10 families, were found. Rotifers were absent from locations without periphyton. Low densities of animals were noted at stations near urban centres and in the estuaries of the Mirna, Rãa, Rjeina and Krka rivers. Several species were found in all of the rivers studied, but always in low numbers. Most of these species are generally considered to be euryvalent and cosmopolitan.     

Rotifer Species Assemblages in Three Freshwater Habitats of Manipur,India

The present commentary deals with the diversity of rotifers from three different habitats that include a river, lake and an irrigation canal from Manipur, India. Using the samples (n = 288) spanning over a 2-year period the species richness and the abundance of rotifers were assessed. A total of 34 species of rotifers from 11 families were observed with varying relative abundance, with the diversity indices (Shannon–Wiener, H’) ranging between 2.98 and 3.23. The species composition of the three habitats differed considerably, as evident from the multivariate analysis. In the lake habitat, the dominant species was Brachionus calyciflorus (7.9%), while in the irrigation canal the dominant species was Brachionus ruben (10.4%), and for the river habitat the dominant species was B. calyciflorus (11.5%). Using relative abundance of the rotifer species as explanatory variables, the ordination of the 34 species yielded significant differences based on the similarity in the abundance over the sampling period. On the basis of the overall differences in the species composition of rotifers, the three habitats could be segregated significantly (P < 0.05) based on the discriminant function analysis. Although the species composition of rotifers remained similar to other freshwater bodies of the this geographical region, the diversity and community analysis suggested considerable differences with reference to the three habitats, implying significance for limnological management.     

Accumulation of cadmium by plants of Zawar Mines, Rajasthan, India

Several plants of the Zawar Zinc Deposits of Rajasthan (India) accumulate very high levels of cadmium. The maximum concentration namely 420 micrograms g-1 was found in the stems of Crotalaria linifolia. Some other cadmium accumulators with the concentration of the metal in microgram g-1 are Impatients balsamina (380), Dyerophytum indicum (282) and Melhania futteyporensis (245). The sequence of cadmium accumulation in different organs of the same plant species was roots greater than stems greater than leaves. Cadmium levels in the leaves of Celosia argentea, Crotalaria linifolia, Impatiens balsamina and Triumfetta pentandra showed a significant (linear) plant-soil relationship. The respective biological absorption coefficients (BAC - concentration of the element in the plant divided by concentration of the same element in the substrate) for these plants were 2.74, 4.13, 5.49 and 4.65.     

LeaflessEuphorbia on Rajasthan rocks,India I. Ecological life-history

The ecological life-history of “leafless” spurge,Euphorbia caducifolia Haines, which serves as an indicator of rocky and gravelly habitat in Rajasthan (India) is dealt with here. There appear to be two forms in existence: one with red and the other with green inflorescence, which interbreed freely in nature resulting in different shades of red coloured inflorescence. The plant is suitably adapted to xerophytic conditions, but surprisingly the leaves are borne only in summer when there is acute shortage of water. Flowering starts in January–February and the seeds are dispered by March–April. The seeds do not indicate any dormancy but the percentage of germination from different plants vary remarkably. The optimum germination is achieved between 25°–30°C, beyond which it is retarded. Continuous light hastens germination. The seeds are washed down by rains from the rocky slopes where the plants grow and are buried in mud to a depth where germination does not take place, and hence regeneration of the plant is poor.     

Nomadization in Rajasthan, India: Migration, Institutions, and Economy

Despite a global trend toward settlement, the incidence of pastoral nomadism is on the rise in the Marwar region of Rajasthan, India. Typical explanations for this change use models of population pressure; increasing herds and decreasing pasture are held to blame. This explanation, however intuitive, is unsatisfactory. Instead, changing institutional and economic patterns are creating new contexts for strategic movement. Bottlenecks in the yearly resource calendar, caused by the disintegration of obligatory social relationships, force migrations during periods of scarcity. Changes in the volume and pattern of the meat and wool markets have also created opportunities for migrating pastoralists. Producers increase their access to markets and the reproductive rate of their herd through long, annual, migration. While nomadism is a general adaptation to changes in the socioeconomic conditions of the region, differential resource endowments account for the range of strategies; wealthy herders have opportunities not enjoyed by more marginal producers.     

Contributions to the rotifer fauna of ORISSA,India

This paper deals with 36 species of monogonont rotifers (belonging to 10 eurotatorien families) collected from Sambalpur (Orissa State) in Eastern India. Of the reported taxa, 15 species have been added as new records to the previous list from this region while one species represents a new record from this country.     

Unrecorded Ethnomedicinal Uses of Biodiversity from Tadgarh-Raoli Wildlife Sanctuary, Rajasthan, India

The World Health Organization(WHO)estimatesthat as manyas80%of the world′s populationrely pri-marily on plant and animal-based medicines.Amongthe252essential chemicals that have been selected bythe World Health Organization,11.1%comefrompla-nts,and8.7%fr…     

A new species of Gigaspora from desert soils of Rajasthan,India

A new species of the endogonaceous fungus Gigaspora, isolated from the Indian semi-arid region, is described. The fungus, named G. tuberculata, produces rusty-brown azygospores with septate subtending hypha. The azygospores bear warts all over the outer wall. The shape, size and general appearance of these spores resemble those of Scutellospora persica.Neeraj and A.K. Varma are with the Microbiology Unit, School of Life Sciences, Jawaharlal Nehru University, New Delhi 110 067, India; K.G. Mukerji is with the Applied Mycology Laboratory, Botany Department, University of Delhi, Delhi 110 006, India. B.C. Sharma is with the Department of Textile Engineering, Indian Institute of Technology, New Delhi 110 016, India.     

Gobioid fauna of Veller estuary,Portonovo, S. India

Summary The distribution and the habits of Gobioid fishes in the Vellar Estuary were described.     

Comparative limnology of Sambhar and Didwana lakes (Rajasthan,NW India)

Two alkaline saline inland lakes of Indian arid region were studied during 1984 and 1985, to assess functioning and interaction of various environmental and biological factors. Changes in physical and chemical variables, planktonic composition, chlorophyll content and phytoplankton primary productivity were examined.Salinity in both lakes fluctuated from almost fresh water (1.80), to hypersaline (300) and acted as the main controlling factor for almost all the biotic parameters. Maximum total alkalinities were 2162 mg l^–1 and 2090 mg l^–1, respectively in Sambhar and Didwana lakes. Dissolved oxygen ranged from completely anoxic conditions to maxima of 11.68 and 7.29 mg 1^–1, respectively in Sambhar and Didwana lakes. Nutrient enrichment in the lakes was low.The phytoplankton species composition of Sambhar lake was reduced from an earlier reported 20 genera to only 11 (Nostoc, Microcystis, Spirulina, Aphanocapsa, Oscillatoria, Merismopedia, Nitzschia, Navicula, Synedra, Cosmarium and Closterium). Phytoplankton of Didwana was composed of only 9 genera including Anabaena and Nodularia. Sambhar lake, which once contained Artemia, is now totally devoid of them. On the other hand, Artemia was the most dominant zooplankter in Didwana lake at a salinity range of 15–288. Other zooplankters such as Moina, Cyclops and Brachionus flourished at lower salinity levels in Didwana lake. The seasonal quantitative and qualitative phyto- and zooplankton changes in relation to salinity are documented.     

Diversity and distribution of molluscan fauna of Asthamudi estuary,Kerala, India

The survey of molluscan fauna of Ashtamudi estuary of the southwest coast of India recorded the presence of 119 species classified under 3 classes (Polyplacophora, Gastropoda and Bivalvia), 57 families and 96 genera. The species diversity was dominated by the Gastropoda (69 species), followed by the Bivalvia (49 species) and the Polyplacophora (1 species). The report includes four species recorded for the first time from India: Desmaulus edgarianus (Melvill, 1898), Pilosabia trigona (Gmelin, 1791), Nassarius javanus (Schepman, 1891) and Jorunna labialis (Eliot, 1908). The true diversity of the mangrove region was as good as that of a community with 31.380 (=?31) equally common species; the respective values for the bar mouth and lake regions were 15.516 and 8.997, respectively, indicating that the molluscan species assemblage of the mangrove was the most diverse and of the lake, the least. True β-diversity across this gradient registered 1.792, which means that though there were three communities, they were equivalent to only 1.792 (=?2) effective communities, i.e., the three actual communities were as different from each other as 2 with equal weights and no species in common.

     

Net above-ground biomass and production in the monsoonal vegetation at Jodhpur,Rajasthan, India

The observations on net above-ground biomass and production in a large protected area of monsoonal vegetation at Jodhpur (India) are presented in this paper. With the start of the monsoon (July–August) a distinct increase in biomass was noted and by winter (November–December), the biomass, decreased as there was hardly any moisture in the soil. The ephemerals, especially some of the grasses form the bulk of biomass in the total make-up. The biomass and production appeared to be closely related in the monsoonal vegetation of this area. The maximum biomass value (360.5 g/m²) was observed in the month of September, decreasing thereafter.     

Prevalence of Coxiella burnetii infection among humans and domestic animals of Rajasthan State, India

A total number of 1806 sera comprising 1049 humans and 757 animals from four ecologically different areas of Rajasthan State were tested to determine the prevalence of complement-fixing (CF) antibodies to Coxiella burnetii (C burnett). Of the 1049 human and 757 animal sera tested, antibodies to C. burnetii were detected in 195 sera (18.6 per cent) and 187 sera (24.7 per cent), respectively. Among humans, the prevalence of infection with C. burnetii was highest in the desert area of Barmer district and the hilly area of Bundi district, viz 64.5 per cent and 28.2 per cent, respectively. It was slightly lower in the semi-arid and the arid zones of the State, viz Sirohi (20 per cent) and Jalore (13.7 per cent), whereas the irrigated areas of Kota and Jaipur had the lowest prevalence, 9.9 and 8.4 per cent, respectively. Among animals, the highest prevalence was detected in sheep (39.6 per cent), followed by cattle (29.9 per cent) and goats (18.6 per cent).     

On the dynamics of the hanuman langur populations of jodhpur (Rajasthan,India)

The city of Jodhpur (26°18′N, 73°8′E) supports a population of about 900 hanuman langurs (Presbytis entellus) divided into 24 bisexual troops and 12 all-male bands in an area of 60 km². This population has been censused from 1968 to 1978. Over this period the population of bisexual troops has remained stable around 700, while the population of all-male bands has increased from 160 to 230 individuals. The bisexual troops show a tendency towards a reduction in population growth rate with increasing troop size, with troops over 50–60 tending to split. Very small troops may grow by large scale immigration. Although a number of male changes and mortality through infanticide have been recorded, there is no evidence of a regular periodicity in the occurrence of initial, growth and mature phases in the life history of a bisexual troop. Unlike the bisexual troops, the all-male bands show no tendency towards a reduction in growth rate with the increase in band size, but show a continuous growth of band size over the study period. Langurs of Jodhpur rely heavily on cultivated fields for their sustenance. This cultivation has been on increase over the study period, and since the males invade cultivation more readily, they may have been able to take fuller advantage of these increasing resources and affect a population increase that has not been possible for the bisexual troops.     

Male competition and coalitions in langurs (Presbytis entellus) at Jodhpur,Rajasthan, India

During a 15 month study on free ranging langurs (Presbytis entellus) at Jodhpur, Rajasthan, India, 5 adult male replacements were observed as a result of nontroop male invasions into the home ranges of 3 neighbouring one-male troops comprising 16–28 members each. Jodhpur langurs have no breeding season. Periods of instability during resident male changes lasted 11–119 days. Linear dominance hierarchies could be detected within the 3 main rival male bands of 2, 5, and 28–35 members. The respective alphas drove their allies away after their bands succeeded cooperatively at occupying a troop. During gradual replacements interim residencies alternated with multi-male stages. A large band's alpha may have had better chances to win the competition, since adult and nonadult allies functioned as “buffers” in agonistic encounters. The role of kin selection in structuring the composition of male bands and male coalitional behaviour cannot yet be quantified. Tactical “deceit” of powerful males to cause unrealistic expectations and in this way agonistic engagement of less strong males can be ruled out. “Sneaking copulations” is a proximate advantage for subordinate supporters, since they participated in 61.9% of all sexual interactions. Female promiscuity might reflect a strategy to induce male-male competition and thus select for a strong resident.     

Occurrence of a thermocline in two lakes of the semi-arid region in western Rajasthan,India

Water quality samples were obtained monthly or bimonthly 17 times from May 1974 to May 1975 at three stations in Delaware Bay. In addition, two 12-hour cruises were also conducted at one station in February and April 1975. Surface and bottom water samples were taken. Measurements and analyses included temperature, salinity, dissolved oxygen, silicate, nitrate and nitrite, orthophosphate, ammonia, chlorophylls a, b, and c, phaeopigments, and carotenoids. The annual pattern of temperature was typical of an estuary in the mid-Atlantic Bight. Salinity and dissolved oxygen ranged from 22.9 to 29.7‰ and from 4.53 to 8.53 ml/l, respectively. Nutrient and pigment values showed seasonal peaks. Silicate (30.3 μg-at/1) and orthosphate (1.59 μg-at/1) were highest in September. Highest concentrations of ammonia were commonly measured in July (6.80 μg-at/1) and September (5.13 μg-at/1), and peak concentrations of nitrate and nitrite were recorded in January (24.27 μg-at/l), February (18.2 μg-at/1), and May (16.37 μg-at/1). Peak concentrations of chlorophyll a were measured in August (17.2 μg-at/1), October (15.70 μg-at/1), and March (15.33 μg-at/1). In general, the annual pattern for chlorophylls b and c were similar to chlorophyll a. Comparison with other estuaries and bays (Narrangansett Bay, Long Island Sound, Raritan Bay, and Chesapeake Bay) indicated that concentrations of nutrients and pigments in Delaware Bay were generally similar in magnitude and seasonality, These are the first set of seasonal water quality data for lower Delaware Bay.     

Morphological Form Variation in a Loricate Rotifer,Keratella tropica APSTEIN from a Perennial Pond,Janaktal, Gwalior,India

Morphological form variation in a loricate rotifer, Keratella tropica APSTEIN is decribed. Form variation in this rotifer involves appearance and development of the left postero-lateral spine. The right postero-lateral spine varies, too. It increases with increasing length of lorica and left postero-lateral spine. Three morphological forms, viz. reducta, asymmetrica and heterospina are recognized.