Correction to: Effect of biosolid hydrochar on toxicity to earthworms and brine shrimp

Environmental Geochemistry and Health - Unfortunately, in the original publication of the article, Prof. Yong Sik Ok’s affiliation was incorrectly published. The author’s affiliation is...     

呋喃丹、杀虫双对蚯蚓(Eisenia foetida)的单一和复合毒性

利用滤纸接触法对赤子爱胜蚓(Eiseniafoetida)进行染毒,研究20℃时呋喃丹和杀虫双对蚯蚓的单一及复合急性毒性。试验发现,蚯蚓在这2种农药作用下表现出不同的中毒症状和死亡情况,杀虫双对蚯蚓的毒性大于呋喃丹,48h时杀虫双和呋喃丹的半致死量分别为17.19和54.06μg·cm-2。无论是杀虫双(15.73μg·cm-2)与0～62.90μg·cm-2范围内呋喃丹复合,还是呋喃丹(94.35μg·cm-2)与0～25.16μg·cm-2范围内杀虫双复合,蚯蚓均表现呋喃丹中毒症状;与单一农药相比,复合农药对蚯蚓的致死毒性有高有低,但复合农药剂量变化对蚯蚓死亡率变化的影响小于相应剂量下单一农药对蚯蚓死亡率变化的影响。     

Effect of oxygen and salt on haemolymph oxygen binding in the brine shrimp Artemia franciscana

The oxygen-binding properties of haemolymph from laboratory-reared Artemia franciscana were investigated in vitro. Adult female brine shrimp without eggs were acclimated to seven different combinations of salinity and oxygen. The oxygen affinity (P₅₀) of unprocessed haemolymph rises with acclimation oxygen partial pressure (PO₂) up to normoxic values, after which no influence of oxygen occurs. The increase in P₅₀ with acclimation PO₂ can be explained by the change in proportion of each of three different haemoglobins in the haemolymph. Salinity acclimation has no effect on haemolymph P₅₀. The effects of the different major salts [NaNO₃, NaCl, Ca(NO₃)₂, Mg(NO₃)₂], pH, and the metal-binding ligand EGTA on the oxygen-binding properties of buffered haemolymph (of shrimp acclimated to 10 salinity) were also studied. Little or no effect of these salts could be found. A small Bohr effect (pH 6.5 to 9.1, =-0.11) was noted. Addition of EGTA caused a significant decrease of the oxygen affinity at concentrations up to 50 mmoll^-1.     

菲、芘、1,2,4-三氯苯对蚯蚓的急性毒性效应

测定了草甸棕壤条件下 ,菲、芘和 1,2 ,4-三氯苯单一与复合污染对蚯蚓的急性致死及亚致死效应。结果表明 ,3种化学品的浓度与蚯蚓死亡率显著相关 (α =0 .0 5 ,r菲 =0 .87,r芘 =0 .85 ,r三氯苯 =0 .95 ) ,与蚯蚓亚致死效应的相关性稍低 (α =0 .0 5 ,r菲 =0 .75 ,r芘 =0 .72 ,r三氯苯 =0 .85 )。蚯蚓个体对 3种有机物毒性的耐受程度差别较大。引起蚯蚓死亡的毒性阈值浓度菲和 1,2 ,4-三氯苯均为 2 0mg·kg-1,芘为 2 0 0 0mg·kg-1;引起蚯蚓体重增长率下降的亚急性毒性阈值浓度分别为菲 2 0mg·kg-1、1,2 ,4-三氯苯 3 0 0mg·kg-1、芘 10 0 0mg·kg-1;LC10 0 分别为菲 10 0mg·kg-1,1,2 ,4-三氯苯 3 5 0mg·kg-1。由于芘的低水溶性和低毒性 ,无法计算LC10 0 。实验还表明 ,复合污染主要表现为协同和拮抗作用     

Effect of agrochemicals on earthworms

This review describes the toxic effects of agrochemicals on earthworms. Carbamates are described as extremely toxic to earthworms in comparison to organophosphorus insecticides. Some pesticides have drastic effect on the nervous system of the earthworm. Earthworm can accumulate heavy metals from the soil in higher levels than any other animal. Mercury is twenty times more toxic than chromium.     

Effect of temperature on permeability and drinking rates of the metanauplii of the brine shrimp Artemia sp.

Diffusional permeabilities and drinking rates of 24 h-old Artemia sp. metanauplii incubated at 20 °C were studied at five temperatures: 15, 20, 25, 30, and 35 °C over a period of 6 h. Departures from the incubation temperature resulted in changes in both permeability and drinking rates which both reached their highest values at 35 °C. Metanaupliar permeability and drinking were more elevated than previously reported for adults.     

Oxygen bioavailability and haemoglobins in the brine shrimp Artemia franciscana

Bioavailability of oxygen for the saline-water invertebrate Artemia franciscana was studied, since both oxygen concentration and oxygen diffusion rate change with salinity. Total haemoglobin concentration and the relative contribution of each of three haemoglobins was measured in specimens acclimated to different salinities and oxygen concentrations. Both haemoglobin concentration and contribution were influenced by salinity and the group observed (males, females with and females without eggs). Multiple regression analysis showed that total haemoglobin concentration was better correlated with oxygen concentration than oxygen partial pressure. The relative proportions of haemoglobins 1, 2 and 3 were better correlated with oxygen partial pressure than oxygen concentration. These results are related to the oxygen carrying capacity and oxygen affinity of the haemolymph. Our results show that oxygen bioavailability in a saline-water environment depends on the response (relative contribution of Hb1, Hb2 and Hb3 or total haemoglobin concentration) that is studied. They also show that oxygen concentration and oxygen partial pressure have a different physiological impact on brine shrimp.     

Effect of total cadmium and organic complexing on the uptake of cadmium by the brine shrimp,Artemia franciscana

The effect of total cadmium and organic complexing on the rate of cadmium uptake by the brine shrimp, Artemia franciscana has been studied in chemically defined saltwater solutions. The uptake of cadmium from solution by the laboratory-reared brine shrimp displays saturable uptake kinetics. Uptake of cadmium is linear in time up to a total cadmium concentration of 200 moll^-1 and saturates above 800 moll^-1. Complexation of cadmium with organic ligands decreases the uptake of the metal by the brine shrimp. This is in agreement with the view that the availability of cadmium to aquatic organisms is related to the activity of the free cadmium ion in the solution. There is no evidence that the direct uptake of cadmium complexes is important in determining uptake of cadmium. Cadmium uptake is not, however, a mere function of the free cadmium ion activity in the solution, i.e., cadmium uptake rates may differ by an order of magnitude for the same free cadmium ion activity depending on the complexation conditions. In addition to controlling the free cadmium ion activity, the role of organic ligands in metal ion buffering and metal ion masking appear important factors in determining the availability of the metal to the organism.     

Assessment of pesticide toxicity on earthworms using multiple biomarkers: a review

Environmental Chemistry Letters - Two million tonnes of pesticides are currently used globally to improve crop production, yet these pesticides induce adverse effects on soil quality and...     

农药污染对蚯蚓毒性毒理研究进展

综述了农药污染对蚯蚓个体毒性、种群毒性及复合毒性3个方面的研究进展,认为农药污染对蚯蚓的毒理学研究将会取得更大的发展。     

Nutritional effect of five species of marine algae on the growth,development, and survival of the brine shrimp Artemia salina

Five species of unicellular algae of the same age, cultured bacteria-free under standard growth conditions, were analyzed for chemical composition and fed to different size classes of Artemia salina. The green algae Chlamydomonas sphagnicolo, Dunaliella viridis, Platymonas elliptica and Chlorella conductrix had significantly higher percentages of protein and lipid than did the diatom Nitzschia closterium. Total ash value was highest in populations of N. closterium. Shrimp fed Chlamydomonas sphagnicolo cells assimilated highest percentages of organic matter, while those fed Chlorella conductrix had lowest assimilation rate. Respiration rates were inversely proportional to animal size (weight) and algal cell volume. Growth, survival, rate of sexual maturtion, and sex ratio were dependent on the growth and assimilation efficiencies obtained from each respective algal food. Shrimp fed Chlamydomonas sphagnicolo, D. viridis, or P. elliptica cells displayed highest growth and assimilation efficiencies.     

Modulation of the free amino acid pool and protein content in populations of the brine shrimp Artemia spp.

 Free amino acid (FAA) and protein content were measured in various developmental stages of Artemia franciscana, from cysts to Instar III metanauplii. In addition, decapsulated cysts of 15 Artemia populations from different localities were compared with respect to their FAA and protein content. Furthermore, the content and composition of the FAA pool were modulated by hatching the cysts at various salinities, and by enriching the nauplii with algae or a lipid-enrichment emulsion. The FAA content increased threefold from cysts to nauplii, and Instar III metanauplii contained nearly 50% taurine of total FAA. Cysts of A. franciscana were found to contain one-third the amount of FAA compared to the other Artemia species investigated. The content and pool composition of FAA was successfully modulated in 11 of 13 populations, where by the content of FAA was significantly increased when hatched at high salinity. Finally, enrichment elevated the content of FAA and changed the pool composition, thereby showing a dietary effect. Algal enrichment also increased the protein content. Received: 27 September 1999 / Accepted: 17 July 2000     

Effect of inorganic mercury on the emergence and hatching of the brine shrimpArtemia franciscana

We describe the effect of inorganic mercury on the emergence, hatching and growth ofArtemia franciscana (commercially obtained). At concentrations as low as 0.01µmol 1^–1, mercury delays development of the organism, but the effect on the final number of developed brine shrimp is small. At higher concentrations, mercury has a dramatic effect, inhibiting the developmental process at the emergence and hatching stages. As recorded by light and scanning electron microscopy, organisms stalled at emergence are not immediately killed. Their eye spots continue to darken and some may hatch although partially enclosed in the cyst shell. Completely emerged prenauplii in the presence of mercury often have an abnormal oval shape while hatched organisms may display shortened and deformed bodies and exhibit restricted movement. The results demonstrate that emergingA. franciscana are very sensitive to inorganic mercury and the potential usefulness of this organism for the study of metal effects upon physiological processes is indicated.     

Two-step hydrothermal conversion of biomass waste to humic acid using hydrochar as intermediate

Converting biomass materials to humic acid is a sustainable method for humic acid production and achieve biomass valorization. A two-step hydrothermal treatment method was adopted in this study to produce humic acid from corn stalks. In the first step of the process, hydrochar was prepared at different hydrothermal temperatures and pH values. Their chemical properties were then analyzed, and the hydrochar-derived humic acids were produced under alkaline hydrothermal conditions (denoted as HHA_alk). The hydrochar, prepared under high temperature (200 °C) and strong acidic (pH 0) conditions, achieved high HHA_alk yields (i.e., 67.9 wt% and 68.8 wt% calculated based on weight of hydrochar). The sources of HHA_alk formation were as follows: 1) production in the hydrochar preparation stage, and 2) increment under the alkaline hydrothermal treatment of hydrochar. The degree of hydrochar unsaturation was suggested as an indicator for evaluating the hydrochar humification potential under alkaline hydrothermal conditions. This study provides an important reference for the preparation of suitable hydrochar with high hydrothermal humification potential.     

A simulation model to evaluate the impacts of invasive earthworms on soil carbon dynamics

Recent studies have reported that earthworm invasions alter native communities and impact nutrient cycling in terrestrial ecosystems. We developed a simulation model to evaluate the potential impacts of earthworm invasions on carbon dynamics, taking into consideration earthworm feeding strategies and priming effects on the microorganisms through their casting activities. Responses of carbon stocks (forest litter, soil organic matter, microbial biomass and earthworm populations) and carbon fluxes (litter decomposition, earthworm consumption, and microbial respiration) were used to evaluate an earthworm invasion of a forest ecosystem. Data from a northern temperate forest (Arnot Forest, New York) were adapted for model calibration and evaluation. Simulation results suggest that the impact and outcome of earthworm invasions are affected by pre-invasion resource availability (litter and soil organic matter), invasive earthworm assemblages (particularly feeding strategy), and invasion history (associated with earthworm population dynamics). The abovementioned factors may also determine invasion progress of earthworm species. The accuracy of the model could be improved by the addition of environmental modules (e.g., soil water regimes), precise parameters accounting for individual species attributes under different environmental conditions (e.g. utilization ability of different types of food resources), as well as earthworm population dynamics (size and structure) and interactions with predators and other invasive/indigenous species during the invasion progress. Such an earthworm invasion model could provide valuable evaluation of the complicated responses of carbon dynamics to earthworm invasions in a range of forest ecosystems, particularly under global change scenarios.     

接种蚯蚓对红壤氮素矿化特征的影响

在室内恒温培养、间歇破坏性采样的条件下,研究了蚯蚓活动对红壤氮素矿化以及土壤氮素肥力的影响。试验共设置以下四个处理:(1)不接种蚯蚓不施用秸秆的对照处理(S);(2)单接种蚯蚓处理(E);(3)单施秸秆处理(O);(4)蚯蚓 秸秆处理(OE)。分别于培养后的第6,12,18,24,30d进行5次破坏性采样。试验结果显示:在整个培养时期中,无论是否施用秸秆,接种蚯蚓处理(E,OE)的土壤铵态氮含量均较同期相应对照处理(S,O)有显著性提高(p<0.05),到培养结束时,铵态氮含量分别是相应对照处理(S,O)的9.27倍和6.76倍。通过计算不同培养期土壤氮素的矿化速率和累积矿化速率发现,无论有无施用秸秆,接种蚯蚓后(E,OE),土壤氮素矿化速率和累积矿化速率均显著高于(p<0.01)同期相应的无蚯蚓对照处理(S,O),并且在单接种蚯蚓(E)的条件下最高。在整个培养时期中,单接种蚯蚓处理(E)的土壤全氮含量较同期对照处理(S)显著提高了6.7%~32.7%,蚯蚓 秸秆处理(OE)的全氮含量除了在培养第6d外,其它培养时期均较同期单施秸秆处理(O)显著提高(p<0.05)了7.4%~25.4%。     

Recent advances in research on cyclic volatile methylsiloxanes in sediment,soil and biosolid: a review

Three cyclic volatile methylsiloxanes (cVMS) were widely used in various processes of production and industrials and frequently added to consumer products. cVMS are continuously released into the environment, causing increasing environmental and human exposing risks. cVMS were investigated in air, water, biogas, soil, sediment, biosolid and organism. Many scholars focused on the occurrence, behaviours, fate and effects of cVMS in environmental matrices all over the world. However, few studies paid attention to the environmental behaviour of cVMS in the solid phase. We assessed their environmental behaviour and fate in soil, biosolid and sediment. High concentrations of cVMS were detected in biosolids. Volatilisation, adsorption and degradation were the major environmental behaviours for cVMS in the solid phase. Although some aquatic organisms showed an appropriate level of bioaccumulation and bioconcentration, there were no obvious evidence of trophic biomagnification in aquatic food webs for octamethylcyclotetrasiloxane (D4) and decamethylcyclopentasiloxane (D5). In addition, cVMS in the environment have not impacted for natural organisms because the concentrations in soil and sediment have not exceeded the maximum no-observed-effect-concentration threshold. Finally, regarding the major environmental behaviour in soil and sediment, suggestions for further study are proposed.     

Effect of mercury on the survival,respiration, and growth of postlarval white shrimp,Penaeus setiferus

The results of toxicity experiments have shown that a level of 17 ppb ionic mercury is acutely toxic (96-h LC₅₀) to postlarval white shrimp (Penaeus setiferus). In addition, the size of the shrimp, within the range tested (7 to 35 mm) did not significantly alter the toxicity values of mercury to this species. Fifty-seven days pre-exposure to low levels of mercury (0.5 and 1.0 ppb) had no effect on the acute toxicity (96-h LC₅₀) of mercury to the shrimp. The effect of chronic exposure to low levels of mercury on the respiratory rate, growth, and molting rate of postlarval P. setiferus was studied, and the results showed that 60 days exposure to 0.5 and 1.0 ppb mercury did not significantly affect any of these parameters for the postlarvae.     

Effect of water temperature and light intensity on growth rate and toxicity change in Protogonyaulax tamarensis

The effect of water temperature and light intensity on the growth rate and the toxicity of Protogonyaulax tamarensis was examined using a monoclonal culture isolated from Ofunato Bay, Japan in March, 1984. The growth rate decreased with the decrease of either light intensity or temperature. The amount of toxin produced increased concomitantly with the decrease of the growth rate. However, the increase of the toxicity under low growth rate was less remarkable when the growth rate was lowered by the decrease of light intensity. This indicates that photosynthesis plays an important role in the production of toxin in P. tamarensis.