Introduction. Ecologically Meaningful Germination Studies. Types of Seed Dormancy. Germination Ecology of Seeds with Nondeep Physiological Dormancy. Germination Ecology of Seeds with Morphophysiological Dormancy. Germination Ecology of Seeds with Physical Dormancy. Germination Ecology of Seeds in the Persistent Seed Bank. Causes of Within-Species Variations in Seed Dormancy and Germination Characteristics. A Geographical Perspective on Germination Ecology: Tropical and Subtropical Zones. A Geographical Perspective on Germination Ecology: Temperate and Arctic Zones. Germination Ecology of Plants with Specialized Life Cycles and/or Habitats. Biogeographical and Evolutionary Aspects of Seed Dormancy. Subject Index.

A Definitive Book on Seed Ecology@@@Seeds: Ecology, Biogeography, and Evolution of Dormancy and Germination

Floods and droughts are important features of most running water ecosystems, but the alteration of natural flow regimes by recent human activities, such as dam building, raises questions related to both evolution and conservation Among organisms inhabiting running waters, what adaptations exist for surviving floods and droughts? How will the alteration of the frequency, timing and duration of flow extremes affect flood- and drought-adapted organisms? How rapidly can populations evolve in response to altered flow regimes? Here, we identify three modes of adaptation (life history, behavioral and morphological) that plants and animals use to survive floods and/or droughts The mode of adaptation that an organism has determines its vulnerability to different kinds of flow regime alteration The rate of evolution in response to flow regime alteration remains an open question Because humans have now altered the flow regimes of most rivers and many streams, understanding the link between fitness and flow regime is crucial for the effective management and restoration of running water ecosystems

/pdf/adaptation-to-natural-flow-regimes-1z55ndwrg2.pdf

Adaptation to natural flow regimes

In the 12 years since Dudgeon et al. (2006) reviewed major pressures on freshwater ecosystems, the biodiversity crisis in
the world’s lakes, reservoirs, rivers, streams and wetlands has deepened. While lakes, reservoirs and rivers cover only
2.3% of the Earth’s surface, these ecosystems host at least 9.5% of the Earth’s described animal species. Furthermore,
using the World Wide Fund for Nature’s Living Planet Index, freshwater population declines (83% between 1970 and
2014) continue to outpace contemporaneous declines in marine or terrestrial systems. The Anthropocene has brought
multiple new and varied threats that disproportionately impact freshwater systems. We document 12 emerging threats
to freshwater biodiversity that are either entirely new since 2006 or have since intensified: (i) changing climates; (ii)
e-commerce and invasions; (iii) infectious diseases; (iv) harmful algal blooms; (v) expanding hydropower; (vi) emerging
contaminants; (vii) engineered nanomaterials; (viii) microplastic pollution; (ix) light and noise; (x) freshwater salinisation;
(xi) declining calcium; and (xii) cumulative stressors. Effects are evidenced for amphibians, fishes, invertebrates, microbes,
plants, turtles and waterbirds, with potential for ecosystem-level changes through bottom-up and top-down processes.
In our highly uncertain future, the net effects of these threats raise serious concerns for freshwater ecosystems. However,
we also highlight opportunities for conservation gains as a result of novel management tools (e.g. environmental flows,
environmental DNA) and specific conservation-oriented actions (e.g. dam removal, habitat protection policies,managed
relocation of species) that have been met with varying levels of success.Moving forward, we advocate hybrid approaches
that manage fresh waters as crucial ecosystems for human life support as well as essential hotspots of biodiversity and
ecological function. Efforts to reverse global trends in freshwater degradation now depend on bridging an immense gap
between the aspirations of conservation biologists and the accelerating rate of species endangerment.

https://onlinelibrary.wiley.com/doi/pdf/10.1111/brv.12480

Emerging threats and persistent conservation challenges for freshwater biodiversity

Recently a novel DNA virus (Torque Teno Virus (TTV) has been identified in Japan and shown to be associated with elevated aminotransferase s levels after transfusion. However the exact role of TTV in pathogenesis of liver disease is yet to be established. The purpose of this study was to determine the prevalence of TTV in thalassemic patients and its relationship with elevated alanine-aminotransfrase (ALT) and aspartateaminotransfrase (AST). This cross-sectional analysis study was conducted on 452 thallasemic patients. Serums were collected from all of the patients, first ALT and AST levels were determined. Then, after DNA extraction, TTV DNA was amplified and detected using semi-nested PCR, followed by gel electrophoresis. Demographic characteristics and clinical data were collected from each participant for statistical analysis. The findings showed that 160 of 452 (35.4%) samples had TTV DNA detected by PCR. From 160 TTV DNA positive, 98 (61.20%) were female and 62 (38.80%) of them were male (P=0.549). The mean ALT and AST values in TTV positive group were higher than in TTV negative group, and the difference was statistically significant (p<0.0001). The result showed that the prevalence of TTV in thalassemic patients in Jahrom is less than other studies in Iran and the mean ALT and AST values in TTV positive individuals were about 2 times more than in TTV negative individuals.

/pdf/molecular-prevalence-and-clinical-importance-of-torque-teno-2fi9z1ixeg.pdf

Molecular Prevalence and Clinical Importance of Torque Teno Virus Infection in Thalassemia Patients as High Risk Individuals

Salinization, a widespread threat to the structure and ecological functioning of inland and coastal wetlands, is currently occurring at an unprecedented rate and geographic scale. The causes of salinization are diverse and include alterations to freshwater flows, land-clearance, irrigation, disposal of wastewater effluent, sea level rise, storm surges, and applications of de-icing salts. Climate change and anthropogenic modifications to the hydrologic cycle are expected to further increase the extent and severity of wetland salinization. Salinization alters the fundamental physicochemical nature of the soil-water environment, increasing ionic concentrations and altering chemical equilibria and mineral solubility. Increased concentrations of solutes, especially sulfate, alter the biogeochemical cycling of major elements including carbon, nitrogen, phosphorus, sulfur, iron, and silica. The effects of salinization on wetland biogeochemistry typically include decreased inorganic nitrogen removal (with implica...

/pdf/a-global-perspective-on-wetland-salinization-ecological-2n2k6riddk.pdf

A global perspective on wetland salinization: ecological consequences of a growing threat to freshwater wetlands

Replication is usually regarded as an integral part of biological sampling, yet the cost of extensive within-wetland replication prohibits its use in broad-scale monitoring of trends in aquatic invertebrate biodiversity. In this paper, we report results of testing an alternative protocol, whereby only two samples are collected from a wetland per monitoring event and then analysed using ordination to detect any changes in invertebrate biodiversity over time. Simulated data suggested ordination of combined data from the two samples would detect 20% species turnover and be a cost-effective method of monitoring changes in biodiversity, whereas power analyses showed about 10 samples were required to detect 20% change in species richness using ANOVA. Errors will be higher if years with extreme climatic events (e.g. drought), which often have dramatic short-term effects on invertebrate communities, are included in analyses. We also suggest that protocols for monitoring aquatic invertebrate biodiversity should include microinvertebrates. Almost half the species collected from the wetlands in this study were microinvertebrates and their biodiversity was poorly predicted by macroinvertebrate data.

Monitoring change in aquatic invertebrate biodiversity : sample size, faunal elements and analytical methods.

In the wheatbelt region o f inland south-western Australia, extensive dearing of native vegetation for dryland agriculture has reduced evapotran~piratio!1 which, in turn, has caused ground water to nse. Th1s has resulted in widespread secondary salinisation and waterlogging of aquatic and terrestrial environments (GEORGE et al. 1995). Despite the severity and extent of salinisation, the area still has significant conservation value. This was recognised in the State Saliniry Strategy (ANoNYMous 1996), which induded a survey of the region's biodiversity to provide informadon for regional conservation planning. Aquatic invertebrates and waterbirds were censused at 230 wetlands. The survey is nearing completion and there are sufficient data to summarise some components of the biota, such as the aquatic invertebrates of granite outcrops (PINDER et al. 2000) and, ~n ~is study, the aquatic invertebrates that show a d1stmct preference for saline conditions. Although salinity has negative connotat!o?s ~n a region severely affected by secondary salmisanon, naturally saline playas, in extensive palaeodrainage flats, are a promi,nent feature of the wheatbelt landscape. Many of the rivers along the south co~t are also naturally saline. There have been few studies. of the fauna of these saline wetlands. Forty-two salme lakes from two areas of the wheatbelt were sampled by GEDDES et al. (1981), but only a limited suite of crustaceans was identified to species level. BROCK & SHIEL (1983) also induded several wheatbelt sites in a study of saline lake plants and invertebrates of the south-west but the idemification effort was concentrated on some microinvertebrate groups. A more intensive study of aquatic invertebrates, but from a smaller number of saline wetlands in the northern wheatbelt, was carried out by HALsE (1981), and two wetlands affected by secondary salinisation were studied by HALsE et al. (2000a).

/pdf/halophile-aquatic-invertebrates-in-the-wheatbelt-region-of-31fdaiev4e.pdf

Halophile aquatic invertebrates in the wheatbelt region of south-western Australia.

The status of studies on Australian Rotifera is reviewed. Approximately 600 species are known from Australian inland waters, with c. 15% endemicity. The ecology of rotifers in four broad habitat categories (saline lakes, billabongs, reservoirs and rivers) is summarized, and the biogeography of the known fauna considered.

Australian Rotifera: ecology and biogeography

Rotifera from Australian inland waters III. Euchlanidae, Mytilinidae and Trichotriidae (Rotifera : Monogononta).

Length-weight relationships, feeding rates, and surface area and morphology of the third and fourth thoracic limbs of Daphnia carinata and Ceriodaphnia quadrangula s.l. were examined. Weight (W) increased between the square and cube of body length (L). W= 7.88 × 10-7 L2.23, W= 1 .7 × 10-6 L2.26 for D. carinata and C. quadrangula s.l., respectively. Both cladocerans had small (<0.3 µm) intersetular distances. Surface areas (A) of limbs 3 and 4 increased as a power function of body length: A = 5.35 × 10-2 L2.0 (D. carinata); A = 1 .22 L1.6 (C. quadrangula s.l.). Reynolds number was < 1; boundary layers surrounding the setules overlapped at beat rates of 5 and 16 cycles s-1. Filtering rates (K) for both species increased with increasing body length according to K = 1 .8 × 10-4 L2.0 (D. carinata) and K = 1.3 × 10-5 L2.2 (C. quadrangula s.1.). K also increased as a power function of limb surface area. Filtering rates on Ankistrodesmus falcatus decreased above cell concentrations of c. 104 cells ml-1. Hourly feeding rates (No. of cells per animal) increased with increasing cell concentration up to the incipient limiting concentrations and thereafter remained relatively stable. Weight-specific feeding rates for D. carinata decreased with increasing body size but for C. quadrangula s.l. remained relatively constant. D. carinata positively selected particles in the size range 4.8-7.0 µm, whereas C. quadrangula s.l. showed no particle preference within the size range 3-12µm. Both cladocerans showed differences in their feeding behaviour when offered a range of phytoplankton species but both fed most efficiently on A. falcatus. Although these cladocerans had limb morphologies that differentiated them from their Northern Hemisphere counterparts, this was not reflected in their feeding behaviour.

Feeding Behaviour and Limb Morphology of Two Cladocerans with Small Intersetular Distances

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