[Analysis of the Environmental Risk of Livestock Manure Pollution and Resource Treatment Technology].

Rapid development of the livestock and poultry industry has greatly promoted the rural economic prosperity of China. However, the problems resulting from the livestock manure, such as large emissions, low utilization rate, and environmental pollution are also becoming increasingly serious. Based on the current situation of livestock manure discharge in China, the typical contaminants in livestock manure and their pollution characteristics in soil, water, and air were systematically analyzed in this study. Taking heavy metals and antibiotics as the characteristic pollutants, the common risk assessment methods for livestock manure pollution were described. Moreover, the main harmless disposal and recycling treatment technologies of livestock and poultry manure at home and abroad were compared and analyzed. The application prospect and value of these technologies such as the thermochemical conversion method and the biological method in energization or fertilization were evaluated. Furthermore, the prominent problems in the pollution control of livestock manure are discussed, and the development trends in the resource treatment technology of livestock manure were also prospected.

[Research Progress on the Remediation Technology of Herbicide Contamination in Agricultural Soils].

Asthe most-used pesticides in the agricultural production process, herbicides are mainly applied to protect crops from weeds. However, with the increased global demand for food, the dosage of herbicides is rising annually, and the efficacy of herbicides is getting stronger, which can cause some environmental issues including the accumulation, migration and transformation, and toxic effects of herbicides in agricultural soils. According to the characteristics of herbicide contamination and regional agricultural production, developing green and low-carbon technologies to reduce the ecological risks of herbicides to the soil-crop systems is a current concern in the ecological environment field. In this paper, relevant studies in recent years on herbicide pollution management in agricultural soils were identified and reviewed, the research progress and application cases of remediation technologies for herbicide pollution was analyzed and demonstrated, and future research and development tendency regarding the remediation of herbicides pollution was also prospected. Current remediation technologies for herbicides mainly include bioremediation technologies (e.g., microbial remediation, enzyme remediation, and phytoremediation), adsorption, and immobilization technologies (e.g., biochar-based materials). The bioremediation technologieswere rather mature and had been applied to the herbicide-contaminated soil in fields. Additionally, many successful bioremediation cases have been reported. Moreover, in order to enhance the remediation effect on herbicide pollution in agriculture soils, remediation technologies have been gradually developed from a single model to a coupled model with physical,chemical, and biological technology, which can maximize the synergy of the multi-technology application.

[Occurrence, degradation and potential ecological risks of triclosan in environment.] / ä¸‰æ°¯ç”Ÿçš„çŽ¯å¢ƒæ®‹ç•™ã€é™è§£ä»£è°¢åŠå ¶æ½œåœ¨ç”Ÿæ€é£Žé™©.

Triclosan (TCS) is widely used in many kinds of personal care products due to its good antibacterial properties. However, TCS can enter environment in many ways through the consumption of those personal care products, and result in a series of environmental problem. TCS and its metabolites have their own characteristics such as environmental persistence, bioaccumulation and ecological toxicity, which may bring some potential risks to the ecosystem and human health. We summarized the occurrence and distribution characteristics of TCS in the environment, as well as the possible degradation pathways and products. Furthermore, we systemically introduced the bioavai-lability and the ecotoxicological effects of TCS and its metabolites on the reproduction and genetics of organism, and their potential risks to the ecosystem and human health. Finally, we proposed brief suggestions for further studies of TCS.

[Gene cloning and expression analysis of an inducible heat shock protein 70 gene from the polychaete Perinereis aibuhitensis under Cu2+ stress.] / åŒé½¿å›´æ²™èš•è¯±å¯¼åž‹çƒ­ä¼‘å ‹è›‹ç™½70åŸºå› çš„å ‹éš†åŠCu胁迫下的表达分析.

The objective of this study was to evaluate the molecular characteristics of heat shock protein 70 (HSP70) gene, and document changes in HSP70 gene expression upon exposure of Perinereis aibuhitensis to aqueous Cu2+. Full length cDNA of HSP70 was sequenced and the characteristics of the translated protein were determined and compared both with other ragworms species and other invertebrates. The results showed that the cDNA was 2161 bp and consisted of a 5'-terminal untranslated region (UTR) of 48 bp, a 3'-termianl UTR of 142 bp with a canonical polyadenylation signal sequence AATAAA and a poly A tail, and an open reading frame (ORF) of 1971 bp. The HSP70 protein was 656 amino acids with a calculated molecular weight of 71.43 kD and theore-tical isoelectric point of 5.15. Sequence analysis of the protein showed that HSP70 of P. aibuhitensis contained three signature sequences IDLGTTYS, IFDLGGGTFDVSIL and IVLVGGSTRIPKIQK all belonging to the HSP70 family, a cytoplasm characteristic motif of EEVD, and the C-terminal repeats of GGMP. The molecular characteristics of P. aibuhitensis shared 94% identity with other ragworms and 79% identity with other invertebrates. In ragworms exposed to Cu2+, expression of HSP70 mRNA increased significantly with Cu2+ concentration (0.2-5.0 mg·L-1), and it reached the peak on 1-day exposure. In summary, the molecular characteristics of HSP70 of P. aibuhitensis were described, and its gene expression was inducible by exposure to aqueous Cu2+, suggesting HSP70 has potential to become a useful molecular biomarker of environmental pollution.

[Influences of petroleum hydrocarbons on accumulation of cadmium and induction of metallothionein in the polychaete Perinereis aibuhitensis].

Ragworm (Polychaeta) is an ecologically important species in intertidal mudflats and estuaries and is recognized as a sentinel species for environmental monitoring. In the intertidal belt of China, the ragworm Perinereis aibuhitensis is frequently exposed to various toxicants including cadmium (Cd) and petroleum hydrocarbons (PHCs). The present study investigated the influence of PHCs on accumulation of Cd and the induction of metallothionein (MT) in P. aibuhitensis by means of chronic microcosm experiment in which the ragworms were exposed to Cd or combinations of Cd and PHCs. The accumulation of Cd in P. aibuhitensis increased significantly with the Cd exposure concentration when exposed to Cd alone. Further, the bioconcentration factors (BCFs) for Cd in P. aibuhitensis increased with the duration of exposure. The addition of PHCs in Cd exposure solutions significantly increased the accumulation of Cd in P. aibuhitensis, compared with the control. Exposure to Cd induced the expression of MT, and the expression increased with the concen- tration up to 180 mg · kg(-1) DM Cd at which point the level of induction did not increase. PHCs without Cd did not significantly induce MT in P. aibuhitensis, but the addition of PHCs with Cd did influence the induction of MT compared to Cd without PHCs. Results indicated that PHCs could modulate the expression of MT during co-exposure with Cd. The potential substances other than metals influencing the interpretation of MT expression in wild P. aibuhitensis must be recognized when MT is used as a monitoring index.

[Ecotoxicological effects of chlorotetracycline on earthworm in soil].

Eiseniafoetida was selected to investigate the ecotoxicological effects of chlorotetracycline on the earthworm in soil. The results showed that 1, 10 and 100 mg · kg(-1) chlorotetracycline had no significant effects on earthworm's body mass after a 7-d exposure, but it was significantly inhibited by 10, 100 mg · kg(-1) chlorotetracycline after 21 days. The soluble protein content of earthworm was induced by 1, 10 and 100 mg · kg(-1) chlorotetracycline, and showed a positive response as the con- centration increased. Also, the earthworm treated by 1, 10 and 100 mg · kg(-1) chlorotetracycline induced the increases of SOD, POD and CAT activities to different degrees. The gene expression in earthworm changed significantly after a 28-d exposure. It is suggested that chlorotetracycline had a chronic ecotoxicological effect on earthworm, and the body mass, soluble protein, antioxidant en- zyme and gene expression could be used as the biomarkers to estimate chlorotetracycline toxicity.

[Effects of illumination and seed-soaking reagent on seed germination of Solanum nigrum].

To explore a rapid seed germination method for hyperaccumulator Solanum nigrum, a germination experiment with different illumination and seed-soaking treatments was conducted in constant temperature box and greenhouse, with filter as burgeon base. Under illumination, the germination rate was about 5 times high of that without illumination (P < 0.05), indicating that illumination was one of the prerequisites for the seed germination of S. nigrum. All test seed-soaking reagents could significantly improve the germination rate of S. nigrum (P < 0.05), with the best effect of H2O2. The seeds treated with H2O2 had the shortest germination time. The germination rate of seeds soaked but without cleaning was 2-3 times as high as that of seeds soaked and cleaned with water.

[Heavy metal pollution ecology of macro-fungi: research advances and expectation].

Macro-fungi are the main component of biosphere and one of the ecological resources, and play very important roles in matter cycling and in maintaining ecological balances. This paper summarized and reviewed the research advances in the eco-toxicological effects of heavy metals on macro-fungi, the bioaccumulation function of macro-fungi on heavy metals, the ecological adaptation mechanisms of macro-fungi to heavy metal pollution, the role of macro-fungi as a bio-indicator of heavy metal pollution, and the potential of macro-fungi in the ecological remediation of contaminated environment. To strengthen the researches on the heavy metal pollution ecology of macro-fungi would be of practical significance in the reasonable utilization of macro-fungi resources and in the ecological remediation of contaminated environment.

[Hyperaccumulative characteristics of 7 widely distributing weed species in composite family especially Bidens pilosa to heavy metals].

Hyperaccumulator is the main point of phytoremediating contaminated soils by heavy metals, and the identification of hyperaccumulator is still the difficult and key step of phytoremediation. The outdoor pot-culture experiment was used to study the hyperaccumulative characteristics of 7 widely distributing weed species in Northeast of China to heavy metals. The results in screening experiment showed that Taraxacum mongolicum and Bidens pilosa indicated strong tolerance to Cd single and Cd-Pb-Cu-Zn combined pollution, their Cd concentration in shoot were higher than that in roots, and the Cd enhancement factors (ratio of heavy metal concentration in shoot to that in soil) in shoots were greater than 1 too, which displayed that the two plants were with Cd hyperaccumulative characteristics. In concentration gradient experiment, Cd concentration in leaves of B. pilosa were all greater than 100 mg x kg(-1) the minimum of Cd-hyperaccumulator should have under the conditions of 25, 50, 100 mg x kg(-1) Cd added. Meanwhile, the shoot biomass of B. pilosa did not reduce significantly (p <0.05), Cd concentration in its shoots were higher than those in roots. But for T. mongolicum, Cd concentration in its shoots were not greater than 100 mg x kg(-1) in any treatment. Thus, only B. pilosa can be regarded as Cd-hyperaccumulator.

Effects of exogenous chelators on phytoavailability and toxicity of Pb in Zinnia elegans Jacq.

Chelate-enhanced phytoremediation is considered as an effective method for the extraction of lead (Pb) by plants. However, more detailed studies are needed to evaluate the effect of exogenous chelators on phytoavailability and toxicity of Pb in plants, then to find out the proper applied concentration of chelators to minimize the combined toxicity to the plants and maximize phytoavailable Pb. To clarify these questions, the seed germination test of Zinnia elegans Jacq. exposed to solutions containing Pb and four types of chelators including sodium ethylenediamine tetra-acetic acid (Na2EDTA), oxalic acid, tartaric acid and citric acid was observed. The results showed that the roots and shoots treated with equimolar chelators and Pb were longer than those treated with half and two folds of the molar concentrations of Pb. The growth of seedlings was inhibited by surplus addition of chelators, and the toxicity of complexes was less than that of Pb and chelators. In particular, 2.4 mM EDTA and 1.2 mM oxalic acid significantly (P<0.05) increased Pb uptake when the seeds were treated with 2.4 mM Pb. In the 4.8 mM Pb solution, Pb accumulation in the seedlings was markedly (P<0.05) increased by 4.8 mM EDTA, 2.4 mM tartaric acid, 4.8 mM tartaric acid and 2.4 mM citric acid, and amounted to 6752.4, 6453.8, 6541.4 and 6598.3 microg g(-1), respectively. With the superfluous addition of chelators, Pb accumulation in the seedlings decreased in a concentration-dependent manner. When Pb was used at 2.4 mM, an equimolar concentration of EDTA not only increased Pb uptake but also stimulated the seedling growth. Thus, chelating agents in their appropriately concentrations could counteract Pb toxicity, but superfluous chelators resulted in less Pb uptake and growth inhibition of the seedlings.

Phytoremediation of cadmium-contaminated soils by Rorippa globosa using two-phase planting.

BACKGROUND: Phytoextraction of contaminated soils by heavy metals can provide a great promise of commercial development. Although there are more than 400 species of hyperaccumulators found in the world, phytoremediation technology is rarely applied in field practice for remedying contaminated soils, partially due to low biomass and long growth duration for most of discovered hyperaccumulating plants. In order to enhance the metal-removing efficiency in a year, the two-phase planting countermeasure of phytoextraction by harvesting anthesis biomass was investigated on the basis of the newly found Cd-hyperaccumulator Rorippa globosa (Turcz.) Thell. with 107.0 and 150.1 mg/kg of the Cd accumulation in stems and leaves, respectively, when soil Cd added was concentrated to 25.0 mg/kg. METHODS: The field pot-culture experiment was used to observe the distribution property of R. globosa aboveground biomass and to examine characteristics of accumulating Cd by the plant at different growth stages. The concentration of Cd in plants and soils was determined using atomic absorption spectrophotometry (AAS). RESULTS AND DISCUSSION: The results indicated that the total dry stem and leaf biomass of R. globosa harvested at the flowering phase was up to 92.3% of that at its full maturity and the concentration of Cd in stems and leaves harvested at the flowering phase was up to 73.8% and 87.7% of that at the mature phase, respectively. The Cd-removing ratio by shoots of R. globosa harvested at the flowering phase was up to 71.4% of that at the mature phase. It was also found, by observing the growth duration of R. globosa, that the frostless period at the experiment site was twice as long as the growth time from the seedling-transplanted phase to the flowering phase of the hyperaccumulator. CONCLUSION: R. globosa could be transplanted into contaminated soils twice in one year by harvesting the hyperaccumulator at its flowering phase based on climatic conditions of the site and traits of the plant growth. In this sense, the extraction efficiency of Cd in shoots of R. globosa increased 42.8% compared to that of at its single maturity when the plant was transplanted into contaminated soils after it had been harvested at its flowering phase and the plant accumulated Cd from soil at the same extraction ratio at its second flowering phase. Thus, the method of anthesis biomass regulation by the two-phase planting is very significant to increase the Cd-removing efficiency by phytoremediation used in practice over the course of a year. RECOMMENDATION AND OUTLOOK: As for some hyperaccumulators that the growth duration from the seedling-transplanted phase to the flowering phase are short and the concentrations of heavy metals accumulated in their shoots at the flowering phase are high, the efficiency of phytoremediation can greatly be improved using the method of the two-phase planting.

[Cadmium-hyperaccumulator Solanum nigrum L. and its accumulating characteristics].

It is main groundwork and the first step of phytoextraction of its commercial application on a large scale to screen out a series of ideal hyperaccumulators that can effectively remedy contaminated soil by heavy metals, which is also difficult point and front field of contaminated environment phytoremediation. With the properties of strong endurance to adverse environment, fast growing and high reproduction, especially the characteristic of the biomass could increase sharply under feasible environmental factors, weed can supply a gap of discovered hyperaccumulating plants, so it is a kind of ideal remediative resource. A cadmium-hyperaccumulator Solanum nigrum L. (weed) was first discovered by using the pot-culture method arranged in outdoor and sampling-analyzing experiments carried out in heavy metal contaminated areas. The pot-culture experiments show that the average concentration of Cd in stems and leaves of S. nigrum growing in soil added with 25 mg/kg of Cd were all greater than the accepted critical concentration of 100 mg/kg what Cd hyperaccumulator should accumulate. The Cd concentration in its overground parts was higher than that in its roots, and the Cd accumulation coefficient in its overground parts was higher than 1 too. Compared with the control, the overground biomass of S. nigrum under the condition of 25 mg/kg (Cd) was not decreased significantly. Furthermore, it was also confirmed that S. nigrum had basic characteristics of Cd-hyperaccumulator by sample-analyze experiment in contaminated area with heavy metals. This kind of method of identifying hyper accumulators in a clean area is useful to the discovery of materials applied to the phytoremediation of contaminated soils with Cd.

Potential of weed species applied to remediation of soils contaminated with heavy metals.

To screen out a series of ideal plants that can effectively remedy contaminated soils by heavy metals is the main groundwork of phytoremediation engineering and the first step of its commercial application on a large scale. In this study, accumulation and endurance of 45 weed species in 16 families from an agricultural site were in situ examined by using the pot-culture field experiment, and the remediation potential of some weed species with high accumulation of heavy metals was assayed. The results showed that Solanum nigrum and Conyza canadensis can not only accumulate high concentration of Cd, but also strongly endure to single Cd and Cd-Pb-Cu-Zn combined pollution. Thus 2 weed species can be regarded as good hyperaccumulators for the remediation of Cd-contaminated soils. Although there were high Cd-accumulation in Artemigia selengensis, Znula britannica and Cephalanoplos setosum, their biomass was adversely affected due to action of heavy metals in the soils. If the problem of low endurance to heavy metals can be solved by a reinforcer, 3 weed species can be perhaps applied commercially.