Ethnobotany and effects of harvesting on the population ecology ofsyngonanthus nitens (bong.) ruhland (eriocaulaceae), a NTFP from Jalapão region, central Brazil

The handicrafts made fromSyngonanthus nitens scapes have been an important source of income for rural communities in the Jalapão region of Brazil since the late 1990s. This study analyzedS. nitens harvest and management techniques and the economic importance of the handicrafts. We also tested the effects of harvest onS. nitens population ecology. Handicrafts provide about US$1,800/year per artisan, being especially important to women. Experimental scape harvesting in mid-October, which is when knowledgeable artisans harvest and when the seeds are mature, had no consistent effects on population density, plant survival, or reproduction (clonal or sexual) after one year. Since 40% of the new recruits come from seeds, harvest after seed maturation, combined with removal of only the scapes and not the flowerheads, can allow forS. nitens seeds to remain in the populations and help ensure sustainability of the growingS. nitens handicraft activity. Important economic aspects ofS. nitens harvest sustainability include the high value of the handicrafts and the fact they are not perishable.     

Potential impacts of water hyacinth invasion and management on water quality and human health in Lake Tana watershed,Northwest Ethiopia

Incursion of water hyacinth, Eichhornia crassipes, has been a potential threat to Lake Tana and its ecosystem services. Its expansion is currently managed by abstraction (removing by hand); nonetheless, the disposal of mats and formation of pools are remaining problematic. This study aimed to assess the potential effects of water hyacinth and its management on water quality and human health. Biotic and abiotic data were collected on open water, water hyacinth covered and water hyacinth cleared out habitats. A total of 3673 invertebrates belonging to twenty-one families were collected from 45 sites. Culicidae was the most abundant family accounting (37.2%), followed by Unionoidae (19.4%) and Sphaeriidae (8.1%). Abundance of anopheline and culicine larvae were significantly higher in water hyacinth cleared out habitats (p?<?0.05). Water conductivity and total dissolved solids were significantly higher in habitats covered with water hyacinth (p?<?0.05). In conclusion, water hyacinth infestation had a negative impact on water quality and biotic communities. The physical abstraction of water hyacinth provided a very good habitat for the proliferation of mosquito larvae. Therefore, integrating water hyacinth management practices along with mosquito larvae control strategy could help to abate the potential risk of malaria outbreak in the region. In addition, developing watershed scale nutrient management systems could have a vital contribution for managing water hyacinth invasion in the study area.     

Nutrient status and retention in pristine and disturbed wetlands in Uganda: management implications

Wetlands in Uganda experience different forms of human pressure ranging from drainage for agriculture and industrial development to over harvesting of wetland products. In order to develop sustainable management tools for wetland ecosystems in Uganda and the Lake Victoria Region, water quality analyses were carried out in a rural undisturbed (pristine) wetland (Nabugabo wetland in Masaka) and two urban wetlands that are experiencing human and urban development pressure (the Nakivubo wetland in Kampala and Kirinya wetland in Jinja). The former wetland forms the main inflow into Lake Nabugabo while the other two border the northern shore of Lake Victoria, Uganda. Nabugabo wetland buffers Lake Nabugabo against surface runoff from the catchment, while Nakivubo and Kirinya wetlands provides a water treatment function for wastewater from Kampala City and Jinja town respectively, in addition to buffering Lake Victoria against surface runoff. Water quality was assessed in all the wetland sites, and in addition nutrient content and storage was investigated in the main plant species (papyrus, Phragmites, Miscanthidium and cocoyam) in Nakivubo and Kirinya wetlands. A pilot experiment was also carried out to assess the wastewater treatment potential of both the papyrus vegetation and an important agricultural crop Colocasia esculenta (cocoyam). Low electrical conductivity, ammonium–nitrogen and ortho-phosphate concentrations were recorded at the inflow into Nabugabo wetland (41.5 μS/cm; 0.91 mg/l and 0.42 mg/l respectively) compared to the Nakivubo and Kirinya wetlands (335 μS/cm; 31.68 mg/l and 2.83 mg/l and 502 μS/cm; 10 mg/l and 1.87 mg/l respectively). The papyrus vegetation had higher biomass in Nakivubo and Kirinya wetlands (6.7 kg DW m⁻²; 7.2 kg DW m⁻² respectively), followed by Phragmites (6.5, 6.7), cocoyams (6.4, 6.6) and Miscanthidium (4.0, 4.2). The papyrus vegetation also exhibited a higher wastewater treatment potential than the agricultural crop (cocoyam) during the pilot experiment (maximum removal degree of ammonium–nitrogen being 95% and 67% for papyrus and yams). It was concluded that urbanisation pressure reduces natural wetland functioning either through the discharge of wastewater effluent or the degradation of natural wetland vegetation. It is recommended that wetland vegetation be restored to enhance wetland ecosystem functioning and for wetlands that are not yet under agricultural pressure, efforts should be made to halt any future encroachment.     

Managing the natural capital of papyrus within riparian zones of Lake Victoria,Kenya

The harvesting of natural products such as papyrus (Cyperus papyrus L.), whether for subsistence value or for the production of commodities intended for sale at local markets, contributes to the well-being of riparian peoples around Lake Victoria, Kenya. Serious losses of papyrus wetlands across East Africa have been reported, most of which are attributed to increasing anthropogenic stressors. Recent studies have called for restoration of these wetlands, emphasizing the need for sustainable harvesting strategies to be put in place, although few have provided suggestions as to how this might happen in practical terms and, crucially, with the consent and active participation of local communities as key stakeholders. Here we explore the socioeconomic characteristics of livelihoods based on papyrus, presenting data generated from surveys, interviews and group discussions collected at multiple sites within the Nyando river basin, Kenya. Conceptualizing papyrus stands as living stocks of natural capital, we then outline our proposal for maintaining the provisioning services of this species, without compromising the critical ecohydrological functions of these swamps as land–water buffer zones. Finally we suggest how this approach might be adapted for wider dissemination around Lake Victoria and beyond, motivated by what we believe to be the first reported case of successful papyrus restoration by a local community.     

A simulation model for nitrogen retention in a papyrus wetland near Lake Victoria,Uganda (East Africa)

Papyrus wetlands around Lake Victoria, East Africa play an important role in the nutrient flows from the catchment to the lake. A dynamic model for nitrogen cycling was constructed to understand the processes contributing to nitrogen retention in the wetland and to evaluate the effects of papyrus harvesting on the nitrogen absorption capacity of the wetlands. The model had four layers: papyrus mat, water, sludge and sediment. Papyrus growth was modelled as the difference between nitrogen uptake and loss. Nitrogen uptake was modelled with a logistic equation combined with a Monod-type nitrogen limitation. Nitrogen compartments were papyrus plants, organic material in the floating mat; and total ammonia, nitrate and organic nitrogen in the water, sludge and sediment. Apart from the uptake and decay rates of the papyrus, the model included sloughing and settling of mat material into the water, mineralization of organic matter, and nitrification and diffusion of dissolved inorganic nitrogen. Literature data and field measurements were used for parameterization. The model was calibrated with data from Kirinya wetland in Jinja, Uganda which receives effluent from a municipal wastewater treatment plant. The model simulated realistic concentrations of dissolved nitrogen with a stable biomass density of papyrus and predicted accumulation of organic sludge in the wetland. Assuming that this sludge is not washed out of the wetland, the overall nitrogen retention of the wetland over a three-year period was 21.5 g N m⁻² year⁻¹ or about 25% of input. Harvesting 10, 20 and 30% of the papyrus biomass per year increased nitrogen retention capacity of the wetland to 32.3, 36.8 and 38.1 g m⁻² year⁻¹, respectively. Although the nutrient flows estimated by the model are within the ranges found in other papyrus wetlands, the model could be improved with regard to the dynamics of detrital nitrogen. Actual net retention of nitrogen in the sludge is likely to be lower than 21.5 g N m⁻² year⁻¹ because of flushing out of the sludge to the lake during the rainy season.     

What happens in Vegas,better stay in Vegas: <Emphasis Type="Italic">Phragmites australis</Emphasis> hybrids in the Las Vegas Wash

While hybridization between Native and Introduced Phragmites australis has not been documented across much of North America, it poses an ongoing threat to Native P. australis across its range. This is especially true for native populations in the biologically rich, but sparsely distributed wetlands of the southwest United States, which are among the most imperiled systems in North America. We identified multiple Hybrid P. australis stands in the Las Vegas Wash watershed, NV, a key regional link to the Colorado River basin. Rapid urbanization in this watershed has caused striking changes in water and nutrient inputs and the distribution of wetland habitats has also changed, with urban wetlands expanding but an overall reduction in wetland habitats regionally. Native P. australis has likely been present in the Wash wetland community in low abundance for thousands of years, but today Hybrid and Native plants dominate the shoreline along much of the Wash. In contrast, Introduced P. australis is rare, suggesting that opportunities for novel hybridization events remain uncommon. Hybrid crosses derived from both the native and introduced maternal lineages are widespread, although the conditions that precluded their establishment are unknown and we did not find evidence for backcrossing. Spread of Hybrid plants is likely associated with flooding events as well as restoration activities, including revegetation efforts and construction for erosion control, that have redistributed sediments containing P. australis rhizomes. Downstream escape of Hybrid plants to Lake Mead and wetlands throughout the lower Colorado River basin is of management concern as these Hybrids appear vigorous and could spread rapidly.     

Impact of climate variability on the hydrology of the Sudd wetland: signals derived from long term (1900–2000) water balance computations

The Sudd wetland is a huge swampy area (30,000–40,000 km²), with vegetation composed mainly of papyrus, water hyacinth and grasslands. It is located in South Sudan, and is of vital importance for livelihoods, ecosystem services and water resources. Half of the White Nile flow evaporates when passing through the Sudd (~16,000 10⁶ m³/year). Historically, this phenomenon triggered several water conservation projects in the Nile region (the Jonglei Canal Project). However, the available information on the hydrology of the Sudd is very limited, and mostly outdated. This paper investigates the long term dynamics of the Sudd hydroclimatology (water balance components), and how it affects the wetland areal extent. The water balance results show that the extent of the Sudd wetland area is determined both by the regional climate (outflow from Lake Victoria) and the local climate, represented by precipitation and evaporation over the wetland itself. The long term trends of the Sudd hydrology from 1900 to 2000 have been analyzed with the Mann–Kendall test statistics. The water flows into and out of the Sudd demonstrate a statistically significant increasing trends during the last 100 years. This can be attributed to increasing rainfall over Lake Victoria in the early 1960s. The daily maximum and minimum temperature in the Sudd shows an increasing trend of 0.6 and 1.5 °C, respectively, over the last 100 years. However, this has not caused any change of the wetland actual evaporation (open water evaporation plus plant transpiration). The impact of the temperature rise has likely been compensated by a reduction of the relative humidity and solar radiation over the wetland. The statistical test shows that both relative humidity and solar radiation (sunshine hours) has significantly decreased, each reduced by 10 % over the last 50 year. The precipitation over the Sudd showed no significant change during the last 100 years. On the other hand, the areal extent of the Sudd wetland increased by 19,000 km² (80 %) during the last 100 years, as a result of the increased inflows. The long term variability of the Sudd areal extent provides new results and deeper insights of the two-way land surface climate feedbacks, and informs wetland conservation and water resources management for this important tropical wetland.     

Phylogenetic taxonomy of the marine mite genus Rhombognathides (Acari: Halacaridae: Rhombognathinae)

This study examined the impacts of the alien waterweed, water hyacinth, on the abundance and diversity of aquatic macroinvertebrates in the littoral areas of northern Lake Victoria in Uganda. The weed had undergone explosive growth on the lake causing serious disruption to people, the economy and the ecosystem. This study was confined to impact of the weed in the littoral zone, not to the large floating mats of vegetation which float across the lake and clog large areas of shoreline.The littoral area studied comprised of fringing mats of Eichhornia crassipes (Mart) Solms (water hyacinth) to the lakeward of Cyperus papyrus; water hyacinth mats undergoing colonisation by Vossia cuspidata (Roxb.) Griff.; and a typical Cyperus papyrus L shore with no outer floating mat of water hyacinth. Numerical abundance (Nos. m^–2) and diversity (No. of taxa) of macroinvertebrates recovered from pure Eichhornia crassipes and the Eichhornia-Vossia succession increased from the fringe of the Cyperus papyrus towards the open water. In the typical Cyperus papyrus fringe, in the absence of water hyacinth, abundance was highest at the papyrus/open water interface and dropped off sharply towards open water. The Shannon–Weaver diversity index (H) of macroinvertebrates decreased progressively from pure Eichhornia crassipes stands, to Vossia/Eichhornia beds and Cyperus papyrus stands (H=0.56, 0.54 and 0.34, respectively) but were not significantly different. Dissolved oxygen decreased from open water into vegetation where it approached anoxia. Water hyacinth appeared to enhance the abundance and diversity of aquatic macroinvertebrates at the interface with the open water. The impoverished abundance and diversity of the macroinvertebrates deeper into the vegetation mats suggested negative environmental impacts of the water hyacinth when the fringe is too wide. Further research is recommended to establish the optimum width of the fringe of stationery water hyacinth that promotes maximum abundance and diversity of aquatic macroinvertebrates and, possibly, of other aquatic life. Since this study in 1997, there has been a dramatic decrease in Eichhornia infestations and by June 2000 it appeared largely to exist only as fringing vegetation in bays and inlets.     

Effects of resource pulses on nutrient availability,ecosystem productivity,and temporal variability following a stochastic disturbance in eutrophic glacial lakes

Tropical macrophytes sold in the live garden trade are perceived as unlikely to invade temperate regions owing to climate mismatches. Here we study two tropical macrophytes (Pistia stratiotes and Eichhornia crassipes) not previously considered an invasion risk but which were recently discovered in the Great Lakes, and determine mechanisms that may be responsible for their continued presence including human introduction, reproduction through viable seeds and tolerance of winter conditions. Surveys conducted in 2011 and 2012 revealed recurrent presence of one or both species at some sites. Macrophytes in in situ enclosures failed to survive winter conditions, with plant health declining progressively prior to mortality. Water hyacinth seeds were field-collected, identified using Sanger sequencing, and germinated at 28°C with or without scarification. Germination was highest for scarified versus non-scarified seeds. Human introduction was observed at two sites, one involving both species, the other only water hyacinth. These species likely persist through a combination of annual reintroduction (both species) and possibly by production of viable seed (water hyacinth). Macrophytes, particularly water hyacinth, that were not previously viewed as a threat to the Great Lakes owing to environmental incompatibility may need to be reassessed.     

Colorless sulfur bacteria <Emphasis Type="Italic">Thioploca</Emphasis> from different sites in Lake Baikal

The colorless sulfur bacteria Thioploca spp. found in Lake Baikal are probably a marker for the influx of subterranean mineralized fluids. Bacteria act as a biological filter; by consuming sulfide in their metabolism, they detoxicate it and maintain the purity of Lake Baikal’s water. The bacteria were investigated by various techniques. According to analysis of the 16S rRNA gene fragment, Thioploca sp. from Frolikha Bay, Baikal belongs to the clade of freshwater species found in Lake Biwa and Lake Constance; it is most closely related to Thioploca ingrica.     

Water hyacinth — A potential source of raw material for greaseproof paper

The potential use of water hyacinth as a pulp material for producing greaseproof paper was investigated. The proximate chemical analyses of the raw materials, the morphology of the water hyacinth stalk and fibre, pulp characteristics, and data on the physical properties of the paper hand-sheets formed from water hyacinth and bamboo pulps and their blends are presented. A comparative study of the pulp freeness (°SR) and drainage properties of water hyacinth and bamboo pulps showed that with a high freeness value of the pulps the drainage time increased. Blending of water hyacinth and bamboo pulps increased the physical strength. Paper hand-sheets made with a blend of water hyacinth pulp (75°SR) and bamboo pulp (80°SR), at 75:25 proportion, gave a tear index of 4·90 mN m² g⁻¹, tensile index of 51·10 N mg⁻¹ and burst index of 7·25 kPa m² g⁻¹. These were higher than the values obtained from sheets made with pulp blends (water hyacinth:bamboo) of 80:20 or 90:10. The pulp sheets at a blend proportion of 75:25 also gave satisfactory greaseproof properties.     

Effect of harvesting on temporal papyrus (<Emphasis Type="Italic">Cyperus papyrus</Emphasis>) biomass regeneration potential among swamps in Winam Gulf wetlands of Lake Victoria Basin,Kenya

This study established for the first time the impact of harvesting on post-harvest papyrus (Cyperus papyrus L.) biomass regeneration potential, with two harvesting regimes compared. Above-ground papyrus biomass was determined. Biomass varied with site. Site had no effect on regeneration potential, but monthly harvesting reduced papyrus biomass regeneration potential among sites. However, seasonal (6-monthly) harvesting did not appear to affect papyrus biomass regeneration potential. Exponential and polynomial trend analyses revealed a consistent downward trend for monthly harvest biomass, and the polynomial trend was more linear (F = 97.913; P < 0.001) than periodic (F = 9.617; P < 0.05). The polynomial trend scenario indicated how papyrus biological dynamics are likely to behave as monthly harvests are repeated. This suggests that regeneration potential is significantly reduced with successive monthly harvest, leading to weak spatial connectivity, papyrus stand fragmentation, and increased landscape patchiness. A 6-month harvest regime can be established to regenerate more biomass between harvests than is currently the case, with positive implications for wetland conservation and carbon sequestration. Papyrus harvesters can be kept off the swamps by establishing a riparian buffer zone of agro forestry trees and shrubs which can substitute for the papyrus as it is left to mature. However, while the information presented is useful for papyrus wetland management strategies, it is recognized that the study period was too short to permit a generalized recommendation.     

Contact Matters: Local People’s Perceptions of <Emphasis Type="Italic">Hapalemur alaotrensis</Emphasis> and Implications for Conservation

Understanding factors that influence local community support for conservation projects is critical to their success. Perceptions of wildlife are particularly important in countries where people rely heavily on natural resources for their survival, as is the case in Madagascar. Renowned as one of the “hottest” regions for global biodiversity, Madagascar hosts an exceptional assemblage of lemurs. Yet little is known concerning the knowledge and perceptions of local people toward lemurs. The Lake Alaotra gentle lemur (Hapalemur alaotrensis) is classified as Critically Endangered on the IUCN Red List and restricted to marsh habitat in the Lake Alaotra New Protected Area. Habitat destruction and hunting have brought the lemur to the brink of extinction. In this study we characterize local people’s knowledge, awareness, and perceptions of Hapalemur alaotrensis. We conducted an initial survey with 180 participants in 6 villages with varying distance to Park Bandro, a high-priority conservation zone. During a second survey, we interviewed 50 people in the village adjacent to the park. Our findings demonstrate that fishers are the most knowledgeable local resource users despite having the lowest education levels, and they also are the most concerned with the endemic lemur’s decline. There is a link between environmental awareness and distance in both a literal and figurative sense; the more often people encounter Hapalemur alaotrensis, the more they know about it, and the more likely they are to be concerned about its future. Our study further shows that despite this concern, subsistence is prioritized over conservation in the Alaotra region. Ecological knowledge in the fishers’ communities is a valuable resource that can benefit the conservation of Hapalemur alaotrensis and its marshland habitat if conservation planning and management can align the resource users’ concerns and livelihood needs with biodiversity values.     

Effects of flooding regime on wetland plant growth and species dominance in a mesocosm experiment

Flooding regimes are a primary influence on the wetland plant community. Human-induced disturbance often changes the duration and frequency of flooding in wetlands, and has a marked influence on wetland plant composition and viability. Comprehensive studies of the environmental thresholds of wetland plants are required for the development of proper practices for wetland management and restoration after hydrological disturbance. This study provides a quantitative assessment of the establishment, growth, and community shifts in dominance of three emergent plant species (Scirpus tabernaemontani, Typha orientalis, and Zizania latifolia) typical of South Korean wetlands, under five hydrological regimes (waterlogged, low-level standing water, high-level standing water, intensive periodic flooding, and intermittent flooding) over four growing seasons. A mesocosm experiment was conducted in the campus of Seoul National University, South Korea. The number and biomass of shoots of Z. latifolia responded positively to increased water level and flooding frequency, while that of the other plants did not. Zizania latifolia outcompeted S. tabernaemontani and T. orientalis irrespective of hydrological regime. This study suggests that Z. latifolia can outcompete the other two macrophytes in the field. This study will improve our ability to predict the dynamics of wetland vegetation and so facilitate the formulation of wetland management and restoration strategies.     

Investigation of a traditional reed economy (<Emphasis Type="Italic">Phragmites australis</Emphasis>) under threat: pulp and paper market,values and Netchain at Wuliangsuhai Lake,Inner Mongolia,China

Common Reed (Phragmites australis) is a wetland plant which is distributed worldwide, has a high biomass production, and provides important ecosystem services. In many developing and emerging countries it is an easily available and cheap raw material for diverse utilization, which may contribute significantly to employment and income generation for the local population. This case study investigates the reed utilization for pulp and paper production at the eutrophic Wuliangsuhai Lake, Inner Mongolia, China. We analysed the fluxes of materials and money along the supply chain (reed harvesting, processing and supply to final users, i.e. paper mills) as well as the division of work and costs at each production layer (network), based on the Netchain theory. The results make evident the importance of the paper industry and reed harvesting for local livelihood. They further reveal that the reed economy at Wuliangsuhai Lake is threatened by rising environmental standards for paper mills, change of market conditions and dependency on only two customers. Increasing revenues by finding new consumers or/and products, come to long-term contracts and improving harvesting efficiency are presented as ways to convert these threats into new opportunities.     

Adaptations in phytoplankton life strategies to imposed change in a shallow urban tropical eutrophic reservoir,Garças Reservoir,over 8 years

This study aimed at evaluating the phytoplankton adaptive strategies of phytoplankton in a shallow urban eutrophic tropical reservoir, Garças Reservoir, over temporal and vertical scales. Samples were taken monthly for eight consecutive years (1997–2004) at a fixed set of depths in the water column. At the beginning, the reservoir was eutrophic with 20% of its surface covered by water hyacinth Eichhornia crassipes (phase I). Then, in phase II, water hyacinth grew to cover up to 40–70% of the surface. In phase III it was mechanically removed. After macrophyte removal the limnology changed, drastically. This removal modified nutrient dynamics, drastically reduced water transparency, and increased both primary production and phytoplankton biomass, the latter impeding light penetration. Phytoplankton life strategies during water hyacinth dominance (phase II) responded promptly to this environmental disturbance in conditions of low dissolved oxygen (DO) and soluble reactive phosphorus (SRP) and high free CO₂ values. After macrophyte removal, a permanent cyanobacterial monoculture was established. Phase I was dominated basically by Sphaerocavum brasiliense, mainly during the stratified months, represented by non-flagellate colonies, the M functional group, S-strategists, and greater biomass of species with high maximal axial linear dimension (MLD) and cell volumes. Phase II was dominated by Cryptomonas curvata, C. erosa, C. marssonii, Trachelomonas sculpta, T. volvocinopsis, T. kelloggii, T. hispida, Peridinium spp., Aphanocapsa spp., and Aphanothece spp., and was represented by unicellular flagellate species, Y, W2, K, L_O functional groups, and C-strategists, greater biomass of species with intermediate MLD and cell volumes. Phase III was dominated by Microcystis aeruginosa, M. panniformis, Cylindrospermopsis raciborskii, Planktothrix agardhii, and Aphanizomenon gracile, represented by non-flagellate colonies, M, S, H1, S functional groups, and S and R-strategists, greater biomass of species with high MLD and cell volumes (>50 μm and >10⁴ μm³, respectively).     

Changes in mycorrhizal colonization and overall fungal communities across upland and wetland <Emphasis Type="Italic">Acer</Emphasis> forests of the Virginia Coastal Plain

Arbuscular mycorrhiza (AM) are common in the roots of most plants and provide benefits such as enhanced uptake of soil nutrients and water when the environment limits these resources. Two primary factors proposed in the literature as limiting the extent of mycorrhizal colonization of wetland plants are: (1) the low oxygen environment; and (2) the level of available phosphorus. The present study evaluated AM colonization of maple (Acer) roots and the fungal community structure in paired upland/wetland locations in the Virginia Coastal Plain to determine if wetland conditions affected the root fungal community. The range of observed AM colonization, based on 60 samples collected on 11 dates covering 3 years, was from 4 to 55%. Overall, soil redox potential and available phosphorus concentration were not significant in explaining the difference in AM colonization of Acer roots. In fact, the site with the greatest percent colonization in this study was a wetland site. A comparison of fungal diversity between the pooled wetland site communities and the pooled upland site communities was conducted and the difference was significant (p = 0.003), but the upland sites exhibited the lower diversity. Communities from all sites were dissimilar. Geographic location exerted a greater effect over community structure than did upland versus wetland status. This study concludes that the forested wetland environments studied here neither limited AM colonization nor reduced the overall fungal community and in fact may present a more favorable environment for fungal diversity.     

Growth and photosynthetic activity of <Emphasis Type="Italic">Botryococcus braunii</Emphasis> biofilms

Botryococcus braunii is a green microalga capable of producing large amounts of external long-chain hydrocarbons suitable as a source of biofuel. There have been several studies indicating that cultures of B. braunii can reduce the energy and water requirement for mass biofuel production, especially if non-destructive extraction methods for milking hydrocarbons are used. Growing microalgae as a raw material for biofuel using conventional liquid-based cultivation (i.e., raceway ponds) has yet to be shown to be economically successful. An alternative solid growth (biofilm) cultivation method can markedly reduce the energy requirements and costs associated with the harvesting and dewatering processes. We evaluated the growth of biofilms of several strains of B. braunii (from races A, B, L and S) and found that three of the four tested races successfully grew to stationary phase in 10 weeks with no contamination. Among all races, B. braunii BOT22 (race B) reached the highest biomass and lipid yields (3.80 mg dry weight cm^?2 day^?1 and 1.11 mg dry weight cm^?2). Irrespective of the race, almost all photosynthetic parameters (F _V /F ₀ , PI_ABS and the OJIP curve) showed that the biofilm cultures were more stressed during lag and stationary phases than in logarithmic phase. We also studied the Botryococcus biofilm profiles using confocal microscopy and found that this method is suitable for estimating the overall biomass yield when compared with gravimetric measurement. In conclusion, the growth characteristics (biomass and lipid) and photosynthetic performance of all races indicated that B. braunii BOT22 is the most promising strain for biofilm cultivation.     

Wetland and riparian plant communities at risk of invasion by transgenic herbicide-resistant <Emphasis Type="Italic">Agrostis</Emphasis> spp. in central Oregon

Creeping bentgrass (Agrostis stolonifera) and redtop (A. gigantea) are introduced turfgrasses that are naturalized throughout the northern U.S. Interest in creeping bentgrass has risen following the 2003 escape of a genetically modified (GM), herbicide-resistant cultivar near Madras, Oregon. The objectives of this study were to characterize the floristic attributes of the plant communities associated with naturalized Agrostis populations in the Madras area, and to identify plant communities at risk of invasion by transgenic Agrostis. Vegetation data collected from 62 stratified random vegetation plots with and without A. stolonifera and A. gigantea identified 11 distinct plant communities. Community composition was strongly correlated with an indirect soil moisture index based on the wetland status of individual species. Results indicate that wetland plant communities are at the highest risk of invasion by transgenic A. stolonifera. Also, inter-specific gene flow to A. gigantea could affect additional habitats and plant communities where A. stolonifera is not found. Both A. stolonifera and A. gigantea were invasive in wetland and riparian settings in the Madras study area, and introducing glyphosate (e.g., Roundup^®, Rodeo^®) herbicide tolerance into these populations would eliminate the primary means of control for these species.     

Alterations of Mg<Superscript>2+</Superscript> After Hemorrhagic Shock

The objectives of this study were to measure the concentrations of elements in raw milk by inductively coupled plasma-mass spectrometry (ICP-MS) and evaluate differences in element concentrations among animal species and regions of China. Furthermore, drinking water and feed samples were analyzed to investigate whether the element concentrations in raw milk are correlated with those in water and feed. All samples were analyzed by ICP-MS following microwave-assisted acid digestion. The mean recovery of the elements was 98.7 % from milk, 103.7 % from water, and 93.3 % from a certified reference material (cabbage). Principal component analysis results revealed that element concentrations differed among animal species and regions. Correlation analysis showed that trace elements Mn, Fe, Ni, Ga, Se, Sr, Cs, U in water and Co, Ni, Cu, Se, U in feed were significantly correlated with those in milk (p < 0.05). Toxic and potential toxic elements Cr, As, Cd, Tl, Pb in water and Al, Cr, As, Hg, Tl in feed were significantly correlated with those in milk (p < 0.05). Results of correlation analysis revealed that elements in water and feed might contribute to the elements in milk.