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Revista de biodiversidad y especies en peligro de extinción

Volumen 3, Asunto 2 (2015)

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Biodiversity Congress 2017: Wildlife management practices in Central India: An overview

Anjana Rajput and Dharmendra Verma

Presence or absence of an animal or plant in a region is determined by ecological and historical factors. Animals and plants are living indications of the characteristics of their environment; their ranges mark the places where environmental conditions are the same or similar. Wildlife habitat and species around the world are facing a crisis. It is estimated that global warming may cause the extinction of 15-37% of species by 2050, unlike other environmental losses this one cannot be reversed because nature does not give second chance to biodiversity. In India, the state Madhya Pradesh, the land of pristine biodiversity is very rich in natural resources. There are various mountain ranges i.e. Vindhya, Satpura, Maikal and Aravali. The terrain is blessed with a fine network of many rivers and, unique watershed offers homes for wild animals and plants. There are 64 forest divisions, 9 national parks, 25 sanctuaries and 6 Tiger reserves in the state. Wildlife conservation has become an increasingly important practice due to the negative effects of human actively on wildlife. Habitat loss-due to destruction fragmentation and degradation of habitat is the primary threat to the survival of wildlife. Humans are continually expanding and developing, leading to an invasion of wildlife habitats. As humans continue to grow, they clear forested land to create more space. This stresses wildlife populations as there are fewer homes and food sources to survive. Their conservation in wild habitat through management practices can provide protection to wild plant and animal species. Present paper deals with an overview to the prevailing wildlife conservation practices in Madhya Pradesh. It includes protection, habitat improvement, water development, wildlife health management, monitoring and evaluation of wildlife. Protection is the major component that ensures the security of wildlife and its habitat through; tiger cell, law enforcement, monsoon strategy, elephant patrols, surveillance of footpaths and sensitive areas. These practices are being managed successfully by Indian Forest Service Officers, State Forest Service Officers, in support with Foresters, Forest guards and ministerial staff of the state.

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Biodiversity - 2014: Influence of the season of birth on juvenile growth of Helix aperta snails submitted to controlled conditions of temperature and photoperiod

Tafoughalt Benbellil S

Body growth of Helix aperta snails was studied in laboratory conditions, from hatching to maturity, under four combinations of temperature and photoperiod (20°C, 16 hL:8 hD; 20°C, 8 hL:16 hD; 15°C, 16 hL:8 hD and 15°C, 8 hL:16 hD). The study of the growth is undertaken on three samples of snails all born in laboratory: the samples 1 and 2 were obtained from parents collected from nature in autumn and in spring respectively; the sample 3 was constituted of individuals of the fourth generation of parents reared in the laboratory.

 

The results show clearly that the season of birth have significant effect on growth of Helix aperta snails. The subjects from parents collected in spring, with heavier mean body weights at birth, have a faster growth compared with the individuals born in the laboratory and those from parents collected in autumn. Under the four different combinations of temperature and photoperiod, the end of the growth phase, which coincides with the onset of mating, marking the age of sexual maturity, was only of 21 weeks in sample 2 (born in spring) but of 23 weeks in sample 1 and 3. In fact, snails born in spring reached maturity and started to mate after 21 weeks of growth, while in samples 1 and 3, this was observed 2 weeks later.

 

However, at each of the four combinations of temperature and photoperiod used, even if the animals born in spring have faster growth than the other two samples, all weights obtained at the end of the growth phase are significantly similar. This suggests that the difference in the rate of juvenile growth in snails of the three samples affects the duration of the growth period but not the weight of the animals in adulthood.

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Biodiversity - 2014: Rapid optimum site selection (ROSS) for biodiversity conservation: A new approach for securing ecological sustainability in the developing world

P O Phil-Eze

Selecting sites for biodiversity conservation that commands respect among local communities and ensures ecological sustainability in the developing world, largely dependent on primary economy is a daunting task. This is because the application of already established 32 site selection criteria in the evaluation of conservation sites in the developing world is not only cumbersome, but also time consuming and requires significant funding that many developing countries cannot afford. This is why the many strategic action plans to conserve biodiversity by various governments have not yielded encouraging results. We must therefore harness the collective wisdom of Indigenous technical knowledge (ITK) together with science to create conservation sites in collaboration with local communities especially in regions of intensive oil and gas exploration and production such as the Niger delta region of Nigeria.

 

This presentation leverages from cognate literature and participatory field research to determine how a Rapid optimum site selection (ROSS) with few criteria can be achieved for biodiversity conservation in areas of not only high biodiversity value but also intensive energy development without infringing on sustainable local livelihoods as a means of ensuring ecological sustainability.

 

 

 

 

The established 32 site selection criteria were subjected to Principal components analysis (PCA) and six (6) orthogonal components were identified as the most significant underlying criteria that explained 100% of variance among the 32 site criteria raw data matrix. Thereafter, cluster analysis grouped and ordered the extracted site criteria according to their relative strength as deployable indices for application in site selection. The six site selection criteria identified are here presented to be deployed for Rapid optimum site selection (ROSS) in which most aspect of scientific and indigenous knowledge are encapsulated for a successful biodiversity site selection, biodiversity conservation and ecological sustainability in the developing world.

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Biodiversity - 2014: Biodiversity conservation and ecological assessments of arid zone plants in Thar Desert of India

Sher Mohammed and Pawan K. Kasera

Among the world’s twelve mega-diversity nations, India is an important nation comprising almost all the climatic conditions and ecological zones found in different parts of the world. The Rajasthan desert, i.e. Thar Desert is among the ecologically important regions of India in the diversity of its biological species. The western Indian Thar desert represents a characteristic environment where plants have adapted to arid hostile conditions. Scanty water with erratic rainfall and high temperature has marked effects on the vegetation, but still several plant species are found here, which thrive well despite the inhospitable conditions. The different plant species, which are common in arid environs includes: Aerva persica, Achyranthesaspera, Cleome viscosa, Corchorus depressus, C. tridens, Crotalaria burhia, Heliotropium spp., Leptadenia pyrotechnica, Tephrosia purpurea, Erianthus munja, Prosopis cineraria, Calotropis procera, Tecomella undulata, Ziziphus spp., Citrullus colocynthis, Capparis decidua, Balanities aegytiaca, Maytenus emarginata, Opuntia dillenii, Parkinsonia aculeate, Salvadora oleoides, S. persica, Tamarix spp. Clerodendrum phlomidis, Farsetia hamiltonii, Lycium barbarum, etc. Among grasses, Aristida funiculata, Bracharia ramosa, Cenchrus spp., Chloris virgata, Cynodon dactylon, Dactyloctenium spp., Desmostachya bipinnata, Dicanthium annulatum, Digitaria ascendense, Eleusine compressa, Eragrostis spp., Panicum spp., Tetrapogon tenela, Tragus racemosus, etc. During rainy season a large number of weeds also make their appearance through seeds/underground vegetative parts. Exotic plants like Verbesina enceliodis and Parthenium hysterophorus are very much disturbing the natural biodiversity of Indian desert. Typical desert plants produce different seeds generally after spring season as well as in summer months. As the climate of Indian desert is hostile to plant life, those possessing special adaptations are sustained.

 

In Indian arid zone, water is the master-limiting factor in determining the vegetation pattern of this region. The growth and development of the plants are handicapped by prolonged rainless periods, which threaten plant life with desiccation and complete destruction. Yet, this region sustains large plant diversity. In context of the Indian desert the conservation of biodiversity is essential not only to maintain the most fragile ecological processes and life-support system but also to ensure the sustainable utilization of the species as well as the ecosystem.

 

Due to over-exploitation, a good number of taxa have vanished from the arid zone and many have dwindled in number. Tecomella undulata, popularly known as the desert teak due to its hard wood, was once the climax tree, but at present only a few are found in free state. It has totally been wiped out and used in the manufacture of carved furniture. A highly aridityadapted shrub, Calligonum polygonoides grows on the sand dunes and due to its very long surface running roots, it acts as an excellent sand binder. Digging of this shrub along with its extensive root system is a regular vocation. All the nutritious perennial grasses (Lasiurus sindicus & Panicum turgidum) have been over-grazed since centuries and they are being replaced by short-lived annuals, which are poor in quality.

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Biodiversity - 2014: Nine years of conservation agriculture based cropping systems research in Eastern Africa to soil degradation and mitigate effects of climate change

Tesfay Araya

In Ethiopia, repeated plowing, complete removal of crop residues at harvest, aftermath grazing of crop fields and occurrence of repeated droughts have reduced the biomass return to the soil and aggravated cropland degradation. Conservation Agriculture (CA)-based resource conserving cropping systems may reduce runoff and soil erosion, and improve soil quality, thereby increasing crop productivity. Thus, a long-term tillage experiment has been carried out (2005 to 2013) on a Vertisol to quantify - among others - changes in runoff and soil loss for two local tillage practices, modified to integrate CA principles in semi-arid northern Ethiopia. The experimental layout was a randomized complete block design with three replications on permanent plots of 5 m by 19 m. The tillage treatments were (i) derdero+ (DER+) with a furrow and permanent raised bed planting system, ploughed only once at planting by refreshing the furrow from 2005 to 2013 and 30% standing crop residue retention, (ii) terwah+ (TER+) with furrows made at 1.5 m interval, plowed once at planting, 30% standing crop residue retention and fresh broad beds, and (iii) conventional tillage (CT) with a minimum of three plain tillage operations and complete removal of crop residues. All the plowing and reshaping of the furrows was done using the local ard plough mahresha and wheat, teff, barley and grass peas were grown. Glyphosate was sprayed starting from the third year onwards (2007) at 2 lha1 before planting to control pre-emergent weeds in CA plots. Runoff and soil loss were measured daily. Soil water content was monitored every 6 days. Significantly different (p<0.05) runoff coefficients averaged over 9 years were 14, 22and 30% for DER+, TER+ and CT, respectively. Mean soil losses were 3t ha-1 y-1in DER+, 11in TER+ and 178 in CT. Soil water storage during the growing season was constantly higher in CA-based systems compared with CT. A period of at least three years of cropping was required before improvements in crop yield became significant. Further, modeling of the sediment budgets shows that total soil loss due to sheet and rill erosion in cropland, when CA would be practiced at large scale in a 180 ha catchment, would reduce to581 ty-1, instead of 1109 t y-1 under the current farmer practice. Using NASA/GISS Model II precipitation projections of IPCC scenario A1FI, CA is estimated to reduce soil loss and runoff and mitigate the effect of increased rainfall due to climate change. For smallholder farmers in semi-arid agro-ecosystems, CA-based systems constitute a field rainwater and soil conservation improvement strategy that enhances crop and economic productivity and reduces siltation of reservoirs, especially under changing climate. The reduction in draught power requirement would enable a reduction in oxen density and crop residue demand for livestock feed, which would encourage smallholder farmers to increase biomass return to the soil. Adoption of CA-based systems in the study area requires further work to improve smallholder farmers’ awareness on benefits, to guarantee high standards during implementation and to design appropriate weed management strategies.

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Biodiversity - 2014: Ground water and surface water utilization via bank infiltration method: A case study along the riverbank of Langat River, Selangor

Mohd Khairul Nizar Shamsuddin, Bashirah Mohd Fazli, Saim Suratman and Ahmad Jamalluddin Shaaban

This study was initiated thanks to potential public water system shortage within the Klang Valley within the near future resulted in inadequate volume of raw water sources. Bank infiltration (BI) is seen together of the solutions in providing the specified volume of raw water. Groundwater and surface water utilisation via BI technique provide improvement on quality and quantity for both surface water and groundwater.BI offers an honest practice to treat and protect the surface water as well as groundwater. The practice uses the bed of a reservoir, lake or river and an adjacent sand and gravel aquifer as natural filter and this technology are often applied on to the existing surface water reservoirs, streams, lakes and rivers, and now it's often a guiding think about the hydrogeological investigation of latest source supplies. BI is that the influx of river water to the aquifer induced by a hydraulic gradient. Pumping wells located on the banks at a particular distance from the river creates a pressure head difference between the river and aquifer, which induces the water from the river to flow downward through the aquifer. By applying this system of beverage extraction, two different water resources are used simultaneously. On the one hand, surface water from the river moves towards the well and groundwater of the encompassing aquifer is utilised. Currently BI study isn't well studied and documented in Malaysia. The development is deterred by big project like inter basins water transfer. As more rivers are becoming polluted, more BI scheme might be developed within the near future. In view of the requirements emphasizing on raw water abstraction, the BI study in riverbank of Langat River is administered as a pilot program to develop a far better understanding of the potential and sustainable source of water abstraction, and can provide an honest platform to introduce this system in Malaysia. Areas along Langat River were chosen thanks to the high water demand within the area for public water system and groundwater is perceived together of the source with very high potential to be developed as supplementary source to meet the demand. The objective of this study is to work out the effectiveness of BI and improving the standard of river water, and to work out the effective rate of water abstraction from the alluvial aquifer. Fifty (50) monitoring wells and 4 test wells were constructed at the Jenderam Hilir and Sungai Serai village located at the riverbank of the Langat Rivers. From the boreholes within the study area, it are often deciphered that this area is rich in soil which may be a good potential as an aquifer and filter materials. Resistivity surveys were also conducted to improve the understanding of the subsurface soil stratification. In order to determine the potential of those locations for water source abstraction, pumping tests are administered . Water samplings during the 72 hours pumping tests show that test wells were ready to produce better quality and quantity of water with very low drawdown from the first static water level in the pumping wells. The distance between the river and therefore the test wells depends considerably on hydrogeological characteristics of the study area. In the study area the space between the river and therefore the test wells is a smaller amount than 35 m. Water quality analyses was administered during the pumping test and therefore the results shows a decreasing trends in some parameters in BI method which were very high within the Langat river. Initial results from this study, has shown the light at the end of the tunnel. Riverbank of Langat Rivers in Selangor has great potential for riverbank/bed filtration for water resource abstraction. The players in beverage industry should start the utilisation of this BI technique as a replacement technology of using natural filtration system. The study on the effectiveness of BI may be a proactive effort of NAHRIM to enhance surface water quality as a source for domestic water during a modern urbanised area and conjunctively utilised with groundwater.

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Biodiversity - 2014: Modern pollen assemblage of surface samples and its relationship to vegetation and climate in south-western Madhya Pradesh, India: A review

M F Quamar and S K Bera

Interpreting palaeovegetation and contemporary palaeoclimate from fossil pollen requires information on modern pollen-rain or deposition patterns of pollen/ spores in sediments of tropical deciduous forest (moist as well as dry types) in the area of investigation, which is achieved through the pollen analysis of surface samples, viz. surface soils/sediments, moss cushions (moss polsters), mud samples, spider web samples, leaf surface and bark that reflect modern vegetation and could be of immense help to refine and strengthen the interpretation of fossil pollen samples (Wright 1967; Flenley 1973; Moore & Webb 1978; Birks & Birks 1980; Liu & Lam 1985; Fall 1992). In the science of Quaternary palynology, this type of study has been given various names such as modern pollen-rain studies, modern pollen deposition patterns, modern pollenvegetation relationships, etc. In some advanced literature, the study has been given the name of Response Transfer Function as it serves as a modern analogue for the accurate explanation of the pollen sequences generated from the sedimentary beds in terms of past vegetation and climate in chronological order in the region during the Quaternary Period, especially the Holocene and/or Late Pleistocene epochs (Quamar & Chauhan 2012, 2013b; Chauhan & Quamar 2012a, 2012b).

 

So far as the relationship between the present-day set-up of vegetation and pollen assemblages is concerned, it is not straightforward. Owing to the differences in pollen production, dispersal and preservation (of taxa), some plant taxa are over-represented in pollen records whilst others are either under-represented or not represented at all (Tauber 1965; Prentice 1985; Prentice et al. 1987; Jackson & Lyford 1999; Sugita 2007) which depends on plant species and climatic conditions (Hicks 2001; Spieksma et al. 2003). Anemophilous species producing high quantities of pollen grains are over-represented, whereas species with zoophilous means of pollination produce lower numbers of pollen grains and are under-represented in pollen assemblages (Faegri & Iverson 1964).

 

In tropical regions, traditional pollen analysis was once upon a time thought to be impossible (Faegri 1966; Flenley 1973; Bush 1995) owing to the towering diversity of the tropical pollen flora (Flenley 1973), which was previously regarded as a stumbling block for palynologists to manage, in addition to the effect of pollen production and dispersal (on pollen analysis).

 

However, credit goes to Flenley (1973) who for the first time investigated the modern pollen rain in the tropics systematically. Many tropical pollen taxa are rarely or never encountered in samples, despite their pollen production and dispersal to sample sites, but with the aid of modern pollen spectra the modern pollen deposition pattern could be successfully related to the vegetation. Like most palaeoecological research, the majority of work on modern pollen spectra has been carried out in temperate regions. However, the increasing interest in palaeoecological reconstruction of past tropical environments over the preceding two decades has led to more work on modern pollen spectra. A number of recent studies have been carried out in tropical areas of Africa (Vincens et al. 1997, 2000; El Ghazali & Moore 1998, Elenga et al. 2000), Australia (Kershaw & Stickland 1990; Kershaw & Bulman 1994; Crawley et al. 1994) and the mainland Neotropics (Grabant 1980; Bush 1991; Islebe & Hooghiemstra 1995; Rodgers & Horn 1996; Bush & Rivera 1998; Bush 2000; Bush et al. 2001, Marchant et al. 2001; Weng et al. 2004). In the Carribean islands, a few studies exist of sedimentary pollen profiles from lowland sites (Hodell et al. 1991; Higuera-Gundy et al. 1999), but modern pollen studies are wanting. Modern pollen rain studies were also conducted in Australia (Walker & Sun 2000), Southern Peru (Weng et al. 2004), Dominican Republic (Kennedy at al. 2005), southern Brazil (Behling & Negrelle 2006), tropical Andes (Rull 2006), northern Ecuador (Moscol Olivera et al. 2009), northeast Bolivia (Gosling et al. 2009), southern Ecuadorian Andes (Niemann et al. 2010), northern Belize (Bhattacharya et al. 2011), etc. and had generated data sets on the transfer functions regarding pollen representation to environmental parameters, as well as indicator taxa for particular ecosystems. Haselhorst et al. (2013) also conducted pollen rain studies in Panama and emphasized a better and more accurate reconstruction of palaeoenvironment and palaeoclimate in long-term pollen rain studies. However, in South Asia, especially India and Sri Lanka, Bonnefille et al. (1999), Anupama et al. (2000), Barboni and Bonnefille (2001) have conducted studies to address the modern pollen deposition pattern in tropical evergreen and deciduous forests. From the Indian context, several studies have also been conducted to address the problem, for example, from the foothills of the Himalaya (Sharma 1985; Gupta & Yadav 1992; Chauhan & Sharma 1993; Quamar and Srivastava, 2013; Ranhotra and Bhattacharayya, 2013), Kashmir (Vishnu-Mittre 1966; Vishnu-Mittre & Sharma 1966, Vishnu-Mittre & Robert 1971), Ladakh (Bhattacharyya 1989a), Himachal Pradesh (Sharma 1973; Bhattacharayya 1989b, 1989c; Bera & Gupta 1990), tropical deciduous scrub vegetation in Rajasthan desert (Singh et al. 1973), eastern Madhya Pradesh (Chauhan 1994, 2008; Quamar & Chauhan 2007), southwestern Madhya Pradesh (Quamar & Chauhan 2010, 2011a, 2011b, 2012, 2013a; Chauhan & Quamar 2012a, 2012b), Chhattisgarh (Quamar & Bera 2013a, 2013b, 2013c), Silent Valley, south India (Gupta & Bera 1996), Tamil Nadu (Bera & Gupta 1992), Uttar Pradesh (Sharma et al. 2007; Trivedi & Chauhan 2011)), northeast India (Gupta & Sharma 1985; Bera & Gupta 1992; Bera 2000; Basumatary & Bera 2007, 2010; Dixit & Bera 2011, 2012a, 2012b, 2013; Bera et al. 2012, 2013; Basumatary et al. 2013), South and Little Andaman Islands (Singh et al. 2010) and Odisha (Singh et al. 2011), etc. These studies have provided plausible assessments of the palaeovegetation and contemporary climatic scenarios from their respective regions during the Late Quaternary Period. The present communication, however, reviews the modern pollen rain studies carried out so far from southwestern Madhya Pradesh in India, with a view to refine and strengthen the interpretation of fossil pollen records, allowing the improved resolution of palaeoenvironmental changes (Prentice et al. 1991; Separ et al. 1994).

 

The present study reviews the pattern of modern pollen-rain carried out from south-western Madhya Pradesh, India, which largely revealed that Tectona grandis (teak), despite being an enormous pollen producer (7500 average number of absolute pollen/flower) (Bhattacharya et al., 1999) and the dominant forest constituent (80 to 95% of the total forest constituents), is recorded mostly in low frequencies, attributable to its low pollen dispersal efficiency as well as poor pollen preservation in the sediments. However, Madhuca indica (Mahua) and other dominant members of Sapotaceae (cf. Manilkara hexandra and Mimusops elangi) have always shown theirs’ typical behaviour in the pollen spectra and representing in high frequencies, which is assigned to its local abundance around the provenance of the samples, coupled with high dispersal efficiency as well as good pollen preservation in the sediments. Meanwhile, the other usual and characteristic associates of teak (Tectona grandis) in the tropical deciduous forests, despite being the common elements of the forests, are under-represented, sporadically represented or not represented at all, which could be ascribed to theirs’ low pollen productivity owing to entomogamy. Various factors that affect the deposition pattern of the diverse constituents of the tropical deciduous forests dominated by teak (Tectona grandis) have been discussed and suggestions were also given while interpreting the pollen sequences generated from the sedimentary beds in terms of past vegetation and climate in a chronological order in the region during the Late Quaternary Period.

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Biodiversity - 2015: Single-cell analysis reveals gene-expression heterogeneity in microbial syntrophic dual-culture

Weiwen Zhang

Microbial syntrophic metabolism has been well accepted because the heart of how methanogenic and other anaerobic microbial communities function. Dissimilatory sulfate-reducing prokaryotes (SRB) are a various group of anaerobic bacteria that are widespread in nature that play an important role within the global cycling of carbon and sulfur1,2,3. The SRB are known to possess two major lifestyles: sulfidogenic and syntrophic metabolism. In the presence of sulfate, SRB use it as the terminal electron acceptor during the oxidation of various products of primary fermentations and oxidize them to CO22,4. When sulfate is depleted, SRB in general ferment organic acids and alcohols, producing hydrogen, acetate and carbon dioxide and rely on hydrogen- and acetate-scavenging methanogens to convert these compounds to methane5,6. This working relationship of SRB with methanogens is understood as ‘syntrophy’ and has been considered because the heart of how methanogenic and other anaerobic microbial communities function7. A model syntrophic interaction involves lactate oxidation by Desulfovibrio vulgaris to supply acetate, CO2 and H2 as products, which the methanogen, Methanosarcina barkeri, can then further convert to CH48. The removal of H2 by M. barkeri provides a thermodynamically favorable condition (i.e., low H2 concentration) for the continued oxidation of lactate by D. vulgaris3,8. The advantage of having two different metabolic capabilities is that it raises the chances of survival of SRB in environments where electron acceptors could become depleted3. While the physiology of the symbiotic relationship of SRB and methanogens has been studied for several decades years3,9, relatively little is known about the genes and their expression dynamics associated with the syntrophic interactions, partially thanks to the shortage of suitable methodologies for measurements of biological properties in mixed-culture systems within the past. To address the difficulty , a transcriptomic analysis approach, which is in a position to differentiate transcripts from each of two species participated within the syntrophic relationship, was recently employed to match the gene expression profiles of D. vulgaris in sulfate-limited monocultures and in syntrophic dual-cultures with a hydrogenotrophic methanogen Methanococcus maripaludis10 and of D. vulgaris during its metabolic shift from syntrophic growth with M. barkeri to sulfidogenic growth11. The results showed that between the 2 lifestyles, several hundred genes including those encoding ATPase, hydrogenases and high-molecular-weight cytochrome were differentially regulated, suggesting their potential roles to syntrophic growth relationship in D. vulgaris11,12. Interestingly, a gene cluster encoding several functionally unknown lipoproteins and membrane-bound proteins (DVU0145 to DVU0150) was found up-regulated in syntrophic dual-cultures when compared with the monocultures10 and down-regulated when D. vulgaris cells were shifted from syntrophic to sulfidogenic metabolism11, suggesting they may be involved in syntrophic metabolism. However, so far no further investigation on these genes have been conducted. Single-cell microbiology has attracted significant attention as more evidence suggested that even isogenic populations of microorganisms could have substantial cell-to-cell heterogeneity at both cellular and molecular levels12,13,14,15,16,17. For example, a RT-qPCR analysis of individual cells from the identical Escherichia coli population showed that the expression level of highly expressed the 16S rRNA gene could vary up to ~32-fold between single cells of the same population18. In addition to micro-scale environmental differences, it is currently known that gene-expression stochasticity, or noise, once amplified through generations, could eventually generate heterogeneity at the cellular level in a clonal bacterial population17,19,20. The significant gene-expression heterogeneity observed for a microbial population suggests that by simply harvesting and analyzing mRNA or proteins from whole populations, it may not be able to capture the unique patterns of gene expression related to distinct functional subpopulations. When it comes to mixed cultures, single-cell based analysis may be more valuable as the heterogeneity within a mixed population could be even higher as different types of cells with distinct metabolic profiles, interaction and stress responses, are co-cultivated within one culture21. Although single-cell genomics has been applied to a handful of symbiotic systems, including bacterial symbionts of marine sponges, insects (grasshoppers, termites)22, to our knowledge, the single-cell based gene-expression analysis has thus far not been applied to any syntrophic microbial system and therefore the dynamics of organic phenomenon and metabolic status in cells of syntrophic mixed cultures reminds unclear. In this work, we applied a single-cell RT-qPCR approach to reveal gene-expression heterogeneity during a model syntrophic system of Desulfovibrio vulgaris and Methanosarcina barkeri, as compared with the D. vulgaris monoculture. Using the optimized primers and single-cell analytical protocol, we quantitatively determine geneexpression levels of 6 selected target genes in each of the 120 single cells of D. vulgaris isolated from its monoculture and dualculture with M. barkeri. The results demonstrated very significant cell-to-cell gene-expression heterogeneity for the chosen D. vulgaris genes in both the monoculture and therefore the syntrophic dual-culture. Interestingly, no obvious increase in gene-expression heterogeneity for the chosen genes was observed for the syntrophic dual-culture in comparison with its monoculture, although the community structure and cell-cell interactions have become more complicated in the syntrophic dual-culture. In addition, the single-cell RT-qPCR analysis also provided further evidence that the gene cluster (DVU0148-DVU0150) could also be involved syntrophic metabolism between D. vulgaris and M. barkeri. Finally, the study validated that single-cell RT-qPCR analysis might be a valuable tool in deciphering gene functions and metabolism in mixed-cultured microbial communities.

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Biodiversity - 2015: Fish species identification and biodiversification in Enugu metropolis river by DNA barcoding

Chioma Nwakanma

The inland fisheries in tropical Africa face threats both by stress from climate change and by overexploitation. Species are becoming extinct and populations decline at an alarming but poorly understood rate. Many species may face extinction before they can be identified or described. This presents a problem for conservation planning and prioritization, because those species that have not been identified obviously cannot be protected effectively. Caddy and Garibaldi reported that only 65.09% of worldwide fishery captures reported to the FAO for the year 1996 was identified at species level, ranging from about 90% in temperate areas to less than 40% in tropical regions. Surveys into the accuracies of species identifications have not been reported, but a significant percentage of identifications may still be erroneous. The limitations inherent in morphology-based identification systems and the limited pool of taxonomists paved the way for the introduction of new molecular diagnostic tools for effective species identification. Hitherto, a wide variety of protein-based and DNA-based methods have been evaluated for the molecular identification of fish species in Africa. These studies, however, are not comparable for the purposes of species identification because they lack standardization (e.g. different regions of the mitochondrial genome such as cytochrome b and 16S rDNA were used). Hebert et al. (2003) proposed a single gene sequence to discriminate the vast majority of animal species, using a 650-bp fragment of the 5′ end of the mitochondrial cytochrome c oxidase subunit I (COI) gene as a global bioidentification sequence for animals. This technology (DNA barcoding) relies on the observation that the ‘barcode’ sequence divergence within species is typically much lower than the divergence exhibited between species, making it an effective marker for species identification and discovery. The startling efficiency of the method may arise from selective sweeps and the intricacies of mito-nuclear coadaptation, raising the profile of bioenergetics as a possible speciation mechanism.

DNA barcoding has since gained global support as a rapid, accurate, cost-effective, and broadly applicable tool for species identification, particularly with respect to fishes as coordinated by the fish barcode of life campaign. Barcoding has also been adopted by the census of marine life project, a growing global conglomerate of 50 countries engaged in a 10-year initiative to assess and explain the diversity, distribution, and abundance of life in the ocean. Although there has been criticism of both the philosophical and the practical underpinnings of DNA barcoding, its successful application for both species identification and discovery has been demonstrated in many studies, involving many taxonomic groups, for example birds, fish, fish parasites, bats, spiders, crustaceans, nematodes, earthworms, mosquitoes, and diverse arrays of Lepidoptera. In addition, DNA barcoding strategies are now being applied for other groups of organisms including plants, macroalgae, fungi, protists, and bacteria. Furthermore, DNA barcoding has gained wide application in forensic analysis to investigate cases of illegal poaching, separation of species, gut content analysis in ecological studies, food product analysis and market substitution, and Asian medicine trade regulation. DNA barcoding has also been employed to validate the identity of biomaterial collections and cell lines. A sufficient accumulation of DNA barcodes can also help conservation managers to identify interim priority areas for conservation efforts in the absence of species data. Currently, DNA barcode reference library records are available for more than 1 million sequences representing more than 94,000 species on the barcode of life data systems, an informatics workbench aiding the acquisition, storage, analysis, and publication of DNA barcode records. Nearly, 10% of these records comprise marine and freshwater fish species.

The COI divergence and species identification success based on DNA barcodes have been previously assessed for many freshwater fish species, for example in Canada, Mexico and Guatemala, and Brazil. Since, to date, there is no detailed knowledge about the diversity and distribution of freshwater fish species in Nigeria, the aim of this study was to determine whether DNA barcoding can be used as an effective tool to perform unambiguous species identification of freshwater fishes in this region, with a view toward establishing a DNA barcode reference library for utilization in biodiversity assessment and conservation for the entire country.

Fish is a proteinous animal which plays a vital role in the protection and prevention of human diseases. DNA barcoding which uses the 50 region of the mitochondrial cytochrome c oxidase subunit as the target gene was implored as an efficient tool in the identification of fish species in the Enugu Metropolis River (Nike Lake and Abakpa River). 10-20mg fish tissue sample of 18 species were extracted for DNA using Promega kit. The polymerase chain reaction (PCR) was used to amplify short sequences of mitochondrial DNA, which were denatured and analysed by polyacrylamide gel electrophoresis (native PAGE), for detection of single strand conformation. Polymorphism species specific muscle alignment patterns of DNA bands were obtained for Chrischthys sp, Parachinna sp, Ctenopoma sp, Tilapia sp and for a number of Clarias species. Out of the 18 fish species, only 15 fish samples were analysed using their genomic make-up, 4 out of the 15 samples (Parachinna obscura -2) (Clarias sp -2) did not show statistical significant evidence of spatial genetic differentiation in their nucleotides despite the enormous geographical distance separating populations. The morphological studies on this fish species have shown that these lines of evidence are taxonomically important and also partial differences in genomic nucleotide base pairs when noticed. This difference is the polymorphism, which is the key to flagging new specie in a particular genus can be attributed to environmental changes and diversity.
 

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Biodiversity - 2015: Manure usage in restoration of degraded crop land

Maysoon M Mikha

In the Great Plains of North America, soil degradation particularly by wind erosion became a problem in the late 18th and early 19th century soon after agriculture expanded to the semi-arid region and the land was broken from sod. Soil degradation is a consequence of anthropogenic activity and environmental disturbances that cause alteration in many aspects of soil properties and infl uence crop productivity. Zika and Erb (2009) estimated that annual dryland degradation could reduce global terrestrial net primary productivity by approximately 2%. Th e 2012 United Nation Convention to Combat Desertifi cation stated that the high susceptibility of dryland soils to degradation as a consequence of water defi ciency and drought conditions could infl uence global sustainability and food security (UNCCD, 2012). Furthermore, by 2030 as the world demand for food, energy, and water is anticipated to increase by 50, 45, and 30%, respectively; this requires more land and likely resulting in more land deforestation and ecological degradation (UNCCD, 2012). In the Great Plains of North America, soil degradation, particularly by wind erosion, became a problem in the late 18th and early 19th century soon aft er agriculture expanded to the semiarid region and the land was broken from sod (Stewart, 2004). Th e risk of soil degradation by erosion remained through most of the 20th century. Following World War I, large expanses of the Great Plains suff ered from wind erosion due to the expansion of cultivated land, moldboard plowing, and disking operations (Li et al., 2007) and wheat–fallow cropping systems (Janzen, 2001; Stewart, 2004). Consequently, some farmlands in the Great Plains Region lost their economical activity as a result of losing topsoil, rich with organic materials, to erosion induced by tillage and over-cultivation (Tanaka and Aase, 1989; Stewart, 2004). Topsoil thickness is one of the essential factors in evaluating soil quality and plant productivity (Izaurralde et al., 2006). Th e unique characteristics of topsoil positively influenced nutrient storage and cycling, water and energy transfer, and crop yield. Losing topsoil through erosion decreases the soil organic matter (SOM) pool and negatively infl uences soil properties, which reduce crop productivity (Tanaka and Aase, 1989; Stewart, 2004; Larney and Angers, 2012). The addition of organic amendment was found to not only increase SOM but also may decrease soil bulk density, increase soil hydraulic properties, and improve soil aggregation (Arriaga and Lowery, 2003; Mikha and Rice 2004). Furthermore, many years of organic amendment additions may infl uence soil Agronomy chemical properties and nutrient dynamics. Diacono and Montemurro (2010) reported that long-lasting applications of organic amendments can enhance soil organic carbon (SOC), available K, and extractable P. Annual solid feedlot manure applications over an 11-yr period in Alberta, Canada, increased soil chemical parameters, such as SOM, available P and N, electrical conductivity (EC), and sodium absorption ratio and decreased surface soil pH as the manure application rates increased (Chang et al., 1991). Soil pH decreased 0.3 to 0.7 units more in the surface 0- to 15-cm depth compared with deeper depths. On the other hand, manure additions increased soil pH in the surface 15cm compared with ammonium nitrate (NH4NO3) additions, which was attributed to the basic cations added by the manure (Eghball, 2002).Therefore, some farmlands lost top soil rich with organic materials and plant nutrients and consequently decrease their economic value. This study evaluates land productivity and changes in soil properties of eroded land influenced by (1) nitrogen types (manure vs. commercial fertilizer); (2) nitrogen rates (high vs. low) and (3) tillage practices (no-tillage vs. conventional tillage). Two eroded sites were chosen in central Great Plain Region, one site in Akron, CO with topsoil loss of approximately 17 to 20 cm and the second site located in Hays, KS with topsoil loss of approximately 25 cm. The Akron site was established in 2007 and the Hays site was established in 2006. The annual manure application range between 11 to 15 Mg manure per ha for the low N rate and approximately 22 to 30 Mg manure per ha for the high N rate. Throughout the first 5 years of the study period, weather patron specifically the precipitations affected the yield. The amount of rain and its distribution throughout the growing seasons and during the crop critical period in addition to the ambient temperature explained some yield response to the treatments. The least limiting Water Range (LLWR) was influenced by manure addition. The relationship between the LLWR and crop yields was stronger in Hays site than in Akron site. In Hays site, annual manure addition significantly altered soil chemical properties compared with commercial fertilizer especially at the top 15 cm. Soil organic C and changes in soil organic C were greatly influenced by manure addition. Soil inorganic N leaching was also detected during the winter months. Overall, the addition of organic amendments restored the productivity of eroded soil and improved some aspects of soil quality compared with commercial fertilizer. Apparently, more than 5 years are required to assess the treatment benefits on soil quality and productivity in such eroded land.

Artículo de investigación

Feeding Ecology of Chinkara (Gazella Bennetti Sykes) in Desert National Park, Rajasthan, India

Jaipal BR

Chinkara (Gazella bennetti) is the state animal of Rajasthan and protected under the schedule- I of Wildlife (Protection) Act, 1972. This is herbivore and mainly found in arid and semi-arid regions. Survival of the chinkara is depended on the natural vegetations those are found in its surrounding habitats. Chinkara feeds mainly on twigs, leaves, flowers and fruits of small trees, bushes, grasses and herbs etc. The study was conducted on the feeding ecology of chinkara in Desert National Park. Direct observation technique was used for taking observations. Seasonal variations were found in its feeding preference. During monsoon season chinkara mostly likes grasses and herbs whereas in summer it feeds upon leaves, twigs, flowers, fallen pods and fruits of bushes and trees. Maximum grazing activities were recorded in monsoon season whereas maximum browsing activities were recorded in summer season.
Artículo de revisión

Marine Parasites as an Object and as a Factor in the Problem of Invasive Species in Marine Ecosystems: Reflections on the Topic

Machkevskyi Volodymyr K, Sarah Al-Jufaili, Ridah Khalfan and Nashwa AM Al-Mazrooei

The distribution of organisms in space is a natural function which ensures the spreading of genes and establishment of populations. The insertion of a new species into ecosystems is a process that has been occurring for centuries, and in many cases, is influenced by human interference, whom knowingly or unknowingly aids in spreading different species around the world. Marine parasites, in particular, can act as Invasive Species (IS) and also as environmental factors affecting the free living IS in the Recipient Ecosystem (RE). For Parasite Invaders (PI), there exists mechanisms that prevent its invasion in RE. The mechanisms of elimination of PI are very diverse, from grazing of parasites’ free-living stages by hydrobionts to the defense reactions of native organisms which PI will use as hosts. There are two possibilities to a successful introduction of PI. The first is the “soft” introduction of PI into the system interconnections of RE. The second variant can develop on the dysfunctional scenario for the recipient ecosystem. The result of the introduction depends on the individual characteristics of the PI. Marine parasites can be controlling factors which prohibit or prevent the establishment of free living IS at the invasion area. As a basis for logical constructions, we used the conception of Parasite Systems as normal component of ecosystems.
Artículo de investigación

Caves Biodiversity in the Marine Area of Riviera d'Ulisse Regional Park, Italy: Grotta del Maresciallo Overview

Adriano Madonna, Magdy A. Alwany, Dea Rabbito, Samantha Trocchia, Sofiane Labar, Fagr Kh. Abdel-Gawad, Rosa D’Angelo, Alessandra Gallo, Giulia Guerriero and Gaetano Ciarcia

The caves have a significant economic importance in their role as tourist attraction and are of great importance for the presence of some rare species. The fauna identification in the “Grotta del Maresciallo” cave, situated in the Riviera di Ulisse Regional Park, started in march 2013 by a visual census and molecular approach. The studies allowed to detect 12 classes, 46 families, 47 species with their ecological niches, and the percentage contribution of each group to the Mediterranean marine cave diversity. Furthermore, we report the presence of two thermophilic species, as the star coral, Astroides calycularis (Pallas, 1766) and the goldblotch grouper, Epinephelus costae (Steindachner, 1878); the tropical species, the ringneck blenny Parablennius pilicornis (Cuvier, 1829); the endangered species, the dusky grouper Epinephelus marginatus (Lowe, 1834) included in the IUCN Red List; the rare species, the black brotula Grammonus ater (Risso, 1810), and some uncommon species such as the golden coral shrimp, Stenopus spinosus (Risso, 1826) and the spotted bumblebee shrimp, Gnatophillum elegans (Risso, 1816). Species of economic and medical interest were also recorded. In a DNA barcoding approach, Neighbour Joining (NJ) phylogenetic tree of 25 mitochondrial cytochrome oxidase subunit I species sequences, indicates that COI gene is suitable for an unambiguous identification. This first geological and biological attempt at the Marine Area of the “Grotta del Maresciallo” provides useful indications to focus future investigations, and may become a potential management tool for local administrations to protect these habitats.

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