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PubMed2005

Soil water repellency induced by long-term irrigation with treated sewage effluent.

This study describes soil water repellency developed under prolonged irrigation with treated sewage effluent in a semiarid environment. Soil surface layer (0-5 cm) and soil profile (0-50 cm) transects were sampled at a high resolution at the close of the irrigation season and rainy winter season. Samples from 0- to 5-cm transects were subdivided into 1-cm slices to obtain fine scale resolution of repellency and organic matter distribution. Extreme to severe soil water repellency in the 0- to 5-cm soil surface layer persisted throughout the 2-yr study period in the effluent-irrigated Shamouti orange [Citrus sinensis (L.) Osbeck cv. Shamouti] orchard plot. Nearby Shamouti orange plots irrigated with tap water were either nonrepellent or only somewhat repellent. Repellency was very variable spatially and with depth, appearing in vertically oriented "repellency tongues." Temporal and spatial variability in repellency in the uppermost 5-cm soil surface layer was not related to seasonality, soil moisture content, or soil organic matter content. Nonuniform distribution of soil moisture and fingered flow were observed in the soil profile after both seasons, demonstrating that the repellent layer had a persistent effect on water flow in the soil profile. A lack of correlation between bulk density and volumetric water content in the soil profile demonstrates that the observed nonuniform spatial distribution of moisture results from preferential flow and not heterogeneity in soil properties. Soil water repellency can adversely affect agricultural production, cause contamination of underlying ground water resources, and result in excessive runoff and soil erosion.

Citrus sinensis↗
PubMed2006

Sorption-desorption of carbamazepine from irrigated soils.

Th anti-seizure medication carbamazepine is often found in treated sewage effluent and environmental samples. Carbamazepine has been shown to be very persistent in sewage treatment, as well as ground water. Due to environmental persistence, irrigation with sewage effluent could result in carbamazepine contamination of surface and ground water. To determine the potential for leaching of carbamazepine, a series of adsorption and desorption batch equilibrium experiments were conducted on irrigated soils. It was found that carbamazepine adsorption to biosolid-amended (T) soils had a KD of 19.8 vs. 12.6 for unamended soil. Based on adsorption, carbamazepine leaching potential would be categorized as low. During desorption significant hysteresis was observed and KD increased for both soils. Desorption isotherms also indicate a potential for irreversibly bound carbamazepine in the T soil. Results indicate that initial removal of carbamazepine via adsorption from irrigation water is significant and that desorption characteristics would further limit the mobility of carbamazepine through the soil profile indicating that carbamazepine found in sewage effluent used for irrigation has a low leaching potential.

Adsorption↗
PubMed2006

Evaluation of primary and secondary treated and disinfected wastewater irrigation of tomato and cucumber plants under greenhouse conditions, regarding growth and safety considerations.

Tomato and cucumber seedlings were distributed into 10 groups (five for each plant) of 15 plants each. The plants were irrigated for 10 weeks with primary treated wastewater (group A), secondary treated wastewater (group B), chlorinated secondary treated wastewater (group C), a fertilizer dilution (group F), and tap water (group M). All precautions were taken to secure that there was no direct contact between the wastewater and the edible portions of the crops. During this period and on a weekly basis, the height and number of leaves was monitored, while, at the end, the dry weight of leaves, stems, and roots for each plant of each group was measured. Based on these growth parameters, both types of plant in groups A and F recorded the most significant development compared to the other three groups. The plants irrigated with tap water recorded the smallest development, in every case. Plants in groups B and C were similar, with a slight (but not significant) superiority for the plants irrigated with secondary treated wastewater, probably as a result of some phytotoxic effects of residual chloride in the chlorinated wastewater. The presence of nutrients and specifically nitrogen in the various solutions explains the differences satisfactorily. The vegetables grown on the plants of each group were harvested, and their surface tissue analyzed for total coliforms (TC) and enterococci (EC). Tomatoes grown on the plants of groups A and B recorded the highest values for TC, with 505 and 490 cfu/g, respectively, whereas, for cucumbers, those values were 342 and 450 cfu/g, respectively. Enterococci were detected on the surface of harvested vegetables from groups A and B, but the small number of cases and their random character cannot support any strong relations between the used wastewater and their presence. The TC values in group C were very low, far lower than those if group F. No EC were found in either group C or group F. These primary results suggested that irrigation with appropriate disinfected wastewater, even of such high-risk cultivations of vegetables eaten raw, should not be discarded completely as unsafe, but be reconsidered and studied further. However, the use of undisinfected wastewater in such greenhouse cultivations, where all safety precautions have been taken to prevent any contact of the fruits with the soil or the wastewater, does not prove to be 100% safe.

Consumer Product Safety↗
PubMedDate not supplied

Clinical and nasal irrigation fluid findings in perennial allergic rhinitis.

Ten patients with perennial allergic rhinitis and 10 healthy subjects were studied to determine most discriminative nasal irrigation fluid marker(s) and to compare samples that were collected at baseline and over a 1-hour period, every 15 minutes. The latter were pooled and designated 1-hour sample. In the nasal irrigation we investigated the following inflammatory cells and soluble mediators: eosinophils, neutrophils, granulocyte-macrophage colony-stimulating factor, interleukin-4, interleukin-6, interleukin-8, ECP, EPX, MPO, leukotriene C4, leukotriene B4, prostaglandin E2, tryptase and fibrinogen. Patients with PAR were then treated for 2 weeks with the topical nasal steroid. The only marker that discriminated patients with perennial allergic rhinitis and healthy subjects was eosinophil count (EO%): correspondingly 14.01 +/- 5.8 and 0.18 +/- 0.09, (M +/- SD). Difference between the studied groups did not depend on the time of irrigation, baseline or 1-hour. EO% was also the only marker of a clinically successful treatment with the nasal steroid, 14.01 +/- 5.8 and 0.87 +/- 0.4, before and after treatment respectively. We conclude that EO% is the most sensitive inflammatory marker of perennial allergic rhinitis, and that baseline nasal irrigation can be used to study nasal mucosal inflammation.

Administration, Intranasal↗
PubMed2002

Detection of protozoan parasites and microsporidia in irrigation waters used for crop production.

The occurrence of human pathogenic parasites in irrigation waters used for food crops traditionally eaten raw was investigated. The polymerase chain reaction was used to detect human pathogenic microsporidia in irrigation waters from the United States and several Central American countries. In addition, the occurrence of both Cryptosporidium oocysts and Giardia cysts was determined by immunofluorescent techniques. Twenty-eight percent of the irrigation water samples tested positive for microsporidia, 60% tested positive for Giardia cysts, and 36% tested positive for Cryptosporidium oocysts. The average concentrations in samples from Central America containing Giardia cysts and Cryptosporidium oocysts were 559 cysts and 227 oocysts per 100 liters. In samples from the United States, averages of 25 Giardia cysts per 100 liters and <19 (average detection limit) Cryptosporidium oocysts per 100 liters were detected. Two of the samples that were positive for microsporidia were sequenced, and subsequent database homology comparisons allowed the presumptive identification of two human pathogenic species, Encephalitozoon intestinalis (94% homology) and Pleistophora spp. (89% homology). The presence of human pathogenic parasites in irrigation waters used in the production of crops traditionally consumed raw suggests that there may be a risk of infection to consumers who come in contact with or eat these products.

Animals↗
PubMed2005

Concentrations of Escherichia coli and genetic diversity and antibiotic resistance profiling of Salmonella isolated from irrigation water, packing shed equipment, and fresh produce in Texas.

Fresh produce has been repeatedly implicated as a vehicle in the transmission of foodborne gastroenteritis. In an effort to assess the risk factors involved in the contamination of fresh produce with pathogenic bacteria, a total of 1,257 samples were collected from cantaloupe, oranges, and parsley (both in the field and after processing) and from the environment (i.e., irrigation water, soil, equipment, etc.). Samples were collected twice per season from two production farms per commodity and analyzed for the presence of Salmonella and Escherichia coli. E. coli was detected on all types of commodities (cantaloupe, oranges, and parsley), in irrigation water, and on equipment surfaces. A total of 25 Salmonella isolates were found: 16 from irrigation water, 6 from packing shed equipment, and 3 from washed cantaloupes. Salmonella was not detected on oranges or parsley. Serotyping, pulsed-field gel electrophoresis (PFGE), and repetitive element sequence-based PCR (rep-PCR) assays were applied to all Salmonella isolates to evaluate the genetic diversity of the isolates and to determine relationships between sources of contamination. Using PFGE, Salmonella isolates obtained from irrigation water and equipment were determined to be different from cantaloupe isolates; however, DNA fingerprinting did not conclusively define relationships between contamination sources. All Salmonella isolates were subjected to antimicrobial susceptibility testing using the disk diffusion method, and 20% (5 of 25) of the isolates had intermediate sensitivity to streptomycin. One Salmonella isolate from cantaloupe was resistant to streptomycin.

Anti-Bacterial Agents↗
PubMed1999

Test-retest reliability of open-loop bithermal caloric irrigation responses from healthy young adults.

OBJECTIVE: To determine normal caloric responses and test-retest correlations of caloric responses in a group of otologically normal persons using an open-loop caloric irrigation system. STUDY DESIGN: An open-loop bithermal caloric irrigator was used to obtain maximum slow component speed caloric responses of healthy young persons with a repeat caloric test occurring- 1 week later. SETTING: The caloric examination took place in a university speech and hearing clinic. SUBJECTS: Twenty healthy young adults (10 men and 10 women, ranging in age from 18 to 33 years) who reported no history of dizziness or hearing loss were recruited at a university. They had thresholds of 25 dB HL or better for frequencies 250 of 8000 Hz and had passed an examination performed by an otologist. RESULTS: The mean unilateral weakness (UW) response was 1.73% with a standard deviation of 12.1%. Test retest correlations were 0.82 for UW and 0.80 to 0.90 for individual ear responses. CONCLUSIONS: The results indicate that a minimum of a 25% UW should be present when identifying a significant UW. Also the test-retest correlations were considerably higher using an open-loop irrigator than those obtained using a closed-loop irrigation system in a previously reported study.

Adolescent↗
PubMedDate not supplied

Gingival degerming by povidone-iodine irrigation: bacteremia reduction in extraction procedures.

The purpose of this study was to find out whether or not a certain mouth wash, i.e. povidone-iodine, will reduce the incidence of bacteremia following tooth extraction. The sample was composed of twenty-six patients who were given gingival sulcus irrigation and rinsing prior to tooth extraction. Thirteen patients used povidone-iodine mouthwash and the other 13 patients with an identically matched placebo. Prior to irrigation and rinse, first blood sample is drawn and first gingival sulcus sample is taken. To complete the whole procedure, the patient rinsed with 10-20 ml of assigned coded mouthwash for 30 seconds and then repeated the rinsing after 2 minutes followed by 60 second irrigation with 10-20 ml of the same coded mouthwash, administered in the gingival sulcus and surrounding mucosa of the tooth to be extracted. A second gingival sulcus sample is taken then extraction is performed. A second blood sample is drawn within 3 minutes of extraction. Growth and reduction in bacteremia were determined before, during and after extraction procedure. Results indicated significant reduction in incidence of post-operative bacteremia with povidone-iodine as compared with placebo (P = .01558) and significant reduction in growth of gingival cultures with povidone iodine as compared with placebo (= .65337). Povidone-iodine mouthwash used as a rinse and gingival sulcus irrigant reduced the growth of gingival cultures and the incidence of post-operative bacteremia in more specimen compared to the placebo.

Anti-Infective Agents, Local↗
PubMed2000

Health risk in agricultural villages practicing wastewater irrigation in central Mexico: perspectives for protection.

9,435 individuals participated in a cross-sectional survey in the irrigation districts of the Mezquital Valley (central Mexico). Exposure groups were: 848 households irrigating with untreated wastewater, 544 households irrigating with the effluent from a series of interconnected reservoirs, and 928 households farming with natural rainfall. The unit of analysis was the individual, and the health outcomes included diarrhoeal diseases and Ascaris lumbricoides infection. Water quality was assessed using faecal coliforms (FC) and nematode eggs, as suggested by (WHO, 1989) for the safe use of wastewater in agriculture. Children from households irrigating with untreated wastewater (10(8) FC/100 mL and 135 nematode eggs/L) had a 33% higher risk of diarrhoeal diseases and a fivefold increase in risk of A. lumbricoides infection (OR = 5.71) compared to children from the control group, farming with rainfall. The risk of A. lumbricoides infection in older individuals was even higher (OR = 13.18). The final analysis showed that drinking unboiled water and cultivating vegetables crops were both associated with a higher risk of diarrheal diseases (OR = 1.45 and 2.00); individuals infected with A. lumbricoides infection came mostly from landless households with poorer dwellings and low standards of sanitation (OR = 2.20, 2.23, 1.72 and 1.43, respectively). These results are discussed in the context of health protection measures and policy recommendations.

Adolescent↗
PubMed2000

Evaluation of groundwater pollution potential of sewage-irrigated vegetable growing areas of the eastern fringe of Calcutta city.

In recent years recycling in agriculture is a common method of disposal or utilisation of waste. However, recycling of wastes may cause contamination of groundwater by toxic elements like heavy metals, cationic and anionic contaminants and pathogens. Groundwater of shallow and deep tubewells was collected during 1991 to 1997 from raw sewage effluent irrigated garbage farming areas on the eastern fringe of Calcutta city. In general raw sewage effluents, sludges and sewage-irrigated soils contain very high amounts of cations, anions, organics and heavy metals. It is found that most of the groundwater contained undesirable pH, total dissolved solids, total hardness, calcium, magnesium, phenolic compounds, iron and manganese and the observed values or concentrations were much above the maximum desirable limits specified by World Health Organisation (WHO) and Bureau of Indian Standards (BIS) for use as drinking water. Groundwater of that area may be used for irrigation. Dispersion by leaching of the metals, cationic and anionic contaminants from irrigated soil and from settled bottom sludge in unlined sewage channels are the principal causes of groundwater contamination. Some management plans have been suggested to control further deterioration of groundwater quality.

Agriculture↗
PubMedDate not supplied

Comparison of assurance gold salmonella EIA, BAX for screening/Salmonella, and GENE-TRAK Salmonella DLP rapid assays for detection of Salmonella in alfalfa sprouts and sprout irrigation water.

The Assurance Gold Salmonella EIA, BAX for Screening/Salmonella, and GENE-TRAK Salmonella DLP rapid assays were compared with official cultural methods described in the Bacteriological Analytical Manual (BAM) for analysis of alfalfa sprouts and sprout irrigation water for the presence of Salmonella. The lower limits of detection of 4 serovars of Salmonella cells (S. tennessee, S. muenchen, S. mbandanka, and S. cubana) in pure culture were determined as approximately log10 2, 5, and 6 for the BAX, GENE-TRAK, and Gold EIA, respectively. Despite its low detection limit, the BAX did not perform as well as the other assays in analyzing contaminated sprouts and sprout irrigation water. For 4 different lots of sprouts and sprout irrigation water samples inoculated with the 4 serovars at low [1-2 colony forming units (CFU/g)] and high (68-180 CFU/g) levels, the BAX detected Salmonella in 58/64 (90.6%) of the samples, compared with 64/64 (100%) by the GENE-TRAK, Gold EIA, and BAM methods. Assay performance was also compared for analysis of naturally contaminated sprouts and sprout irrigation water with 3 lots of alfalfa sprouted seeds associated with different salmonellosis outbreaks. Positive assay results for the naturally contaminated samples were Gold EIA 41, GENE-TRAK 36, BAM 33, and BAX 13.

Bacteriological Techniques↗
PubMed2002

Surface and subsurface irrigation with effluents of different qualities and presence of Cryptosporidium oocysts in soil and on crops.

A large variety of human pathogens are excreted in wastewater including bacteria, viruses, protozoan cysts and helminth eggs. In raw sewage, human pathogens reach high numbers, thereafter decreasing successively at each treatment step. However, the final effluents still contain a large fraction of these pathogens that may pose a serious public health. Among the various crops irrigated with effluents, vegetables are the most vulnerable to contamination. Vegetables, usually eaten raw (uncooked) or with rich dressings (causing regrowth of some pathogenic bacteria) pose the main threat to humans. The importance of microbiological and parasitological criteria for reused water has been repeatedly emphasized. Some microbiological recommendations based on epidemiological data have been established for untreated wastewater, there is still a need to define the criteria for effluent quality required for unrestricted crop irrigation. This paper presents a field study comparison of two irrigation methods: surface and subsurface of field crops (mainly vineyard) and follow-up of Cryptosporidium oocysts in soil at different depths (0 to 90 cm). Oocysts were isolated at all depths without a clear pattern of distribution (0 to 640 oocysts/g). In addition different vegetables irrigated with different effluent qualities were tested for the presence of Cryptosporidium oocysts and Giardia cysts. The highest prevalence of oocysts was found on zucchini that has a sticky and hairy outer surface (80 to 10,000 oocysts/0.5 kg).

Agriculture↗
PubMed2004

Intraoperative Arthroscopic Cold Irrigation Solution Does Not Affect Postoperative Pain and Swelling.

OBJECTIVE: To determine what effect using a cold irrigating solution during arthroscopic knee surgery would have on postoperative pain intensity, pain-medicine consumption, and knee joint swelling. DESIGN AND SETTING: We employed a randomized, controlled trial design. Subjects were randomly assigned to either the cold (4 degrees C) irrigating saline group or room-temperature (18 degrees C) irrigating saline (control) group. Subjects were blinded to group assignment. All surgeries were performed at the same hospital by the same surgeon. SUBJECTS: The sample was 93 physically active patients (32 women, 61 men, mean age = 47.4 +/- 15.1 years) who had knee injuries requiring surgery. Those with cold sensitivities or contraindications to the use of cold were excluded. MEASUREMENTS: A 10-cm horizontal visual analog scale was used to measure postoperative pain intensity. Postoperative pain-medicine consumption was recorded using a daily log. Knee joint swelling (girth) was measured at midpatella and 2 in (5.08 cm) above midpatella. Pain and swelling measures were collected before and after surgery. RESULTS: No statistical or clinical differences were found between the cold-saline and control groups for pain, pain-medicine consumption, and postoperative swelling across the first 4 postoperative days. CONCLUSIONS: Our results suggest that using intra-articular cold saline to irrigate the knee joint during arthroscopic surgery had no statistically or clinically significant effect on postoperative pain, medication usage, or swelling in the first 4 postoperative days.

Journal Article↗
PubMed2004

[Heterogeneity of Schistosoma haematobium transmission in irrigated fields].

Heterogeneity of Schistosoma haematobium transmission in irrigated fields. Although irrigated areas exist since a long time in the Niger Valley the distribution of the urinary schistosomiasis does not appear homogeneous, testifying to the existence of limiting or favourable factors. The identification of these factors could lead to a better definition of the distribution of the schistosomiasis risks and to optimise control programmes. The population of five villages about 1,900 inhabitants living in the same irrigated area (Sébéri) was examined at the end of 1999 before treatment and surveyed two and ten months after treatment by praziquantel in order to investigate re-infections. In parallel, the transmission sites were subject to a semi-monthly malacological follow-up from 1998 to 2001 and the water contacts were quantified in the sites of the main village during 2000. Before treatment, schistosomiasis risks appeared related to the proximity between habitat and lateral canals: the infections concerning youngers were all the more intense that the dwellings were close to the canal. The parasitological indices were the highest in the village lacking of other water sources. The morbidity indices followed a similar distribution with maximum values in the children of the 3 villages located to less than 1 km from the canal; however, morbidity was mainly observed in the adult population, in particular male, of the 2 villages which were the most distant from the canal. After treatment, the incidence of the re-infection between 2 and 10 months was comparable in the 3 villages close to the canal (28%) but was significantly weaker in the 2 villages far from the transmission sites (5%). In the villages bordering the canal, the incidence in the children was all the more high since the habitat was close to the canal. Between 1999 and 2000, the collected number of Bulinus truncatus decreased from 1.4 to 0.6 individuals per survey; moreover, no mollusc harbouring parasites was found, representing the decrease of the parasite burden. The abnormal weakness of re-infection, regarding this type of focus, could be explained by the repeated stop of water supply inducing a complete drying out of the canal for 2 months during the year preceding the study. These repeated drying out also resulted in a reduction of the exposure. Whereas the average frequentation of the sites of the canal remained rather comparable between January (cold dry season) and May (dry hot season), it decreased dramatically in September (rainy season but canals were not irrigated this year) from 99 to 11 daily contacts. The use of the lateral canal when filled represented 80% of the contacts. In the event of drying out, 80% of the contacts were transferred in the ponds but not in the river (5% of the contacts whatever the season). These results confirmed (1) that the presence of canals reduced the use of natural sites and (2) that the drying out of the canals induced a total reduction of the contacts.

Adolescent↗
PubMed2005

Synthetic- and bio-polymer use for runoff water quality management in irrigated agriculture.

Low concentrations of synthetic- or bio-polymers in irrigation water can nearly eliminate sediment, N, ortho- and total-P, DOM, pesticides, micro-organisms, and weed seed from runoff. These environmentally safe polymers are employed in various sensitive uses including food processing, animal feeds, and potable water purification. The most common synthetic polymer is anionic, high purity polyacrylamide (PAM), which typically provides 70-90% contaminant elimination. Excellent results are achieved adding only 10 ppm PAM to irrigation water, applying 1-2 kg ha(-1) per irrigation, costing 4 dollars - 12 dollars kg(-1). Biopolymers are less effective. Using twice or higher concentrations, existing biopolymers are approximately 60% effective as PAM, at 2-3 times the cost. A half million ha of US irrigated land use PAM for erosion control and runoff protection. The practice is spreading rapidly in the US and worldwide. Interest in development of biopolymer surrogates for PAM is high. If the supply of cheap natural gas (raw material for PAM synthesis) diminishes, industries may seek alternative polymers. Also "green" perceptions and preferences favor biopolymers for certain applications.

Acrylic Resins↗
PubMed2004

Impact of anaerobically treated and untreated (raw) distillery effluent irrigation on soil microflora, growth, total chlorophyll and protein contents of Phaseolus aureus L.

Impact of distillery effluent (untreated and treated) irrigation on soil microflora of the pots used for growing Phaseolus aureus L. was investigated. The growth of the P. aureus plants as affected by distillery effluent irrigation was also evaluated. The irrigation of the pots by 1-10% distillery effluent (anaerobically treated) stimulated the growth of the soil microflora (increased number of bacteria, fungi and actinomycetes) and P. aureus plants (increased shoot and root lengths, biomass, chlorophyll and protein contents). Further, 15-20% distillery effluent (anaerobically treated) had toxic effect on soil micro flora as indicated by reduced number of bacteria, fungi and actinomycetes. Reduction in shoot, root, lengths, biomass, chlorophyll, protein contents of P. aureus was also observed when irrigated by 15-20% treated distillery effluent. All the concentrations of raw distillery effluent reduced the bacterial population. However, the treated distillery effluent concentrations <10% had stimulatory effect on fungal and actinomycetes population. However, raw effluent concentrations >5% reduced the same. Raw distillery effluent was more toxic to P. aureus than treated distillery effluent as concentrations >5%, had reduced the growth (shoot, root length and biomass) of the test plant. Raw distillery effluent had adverse effect to total chlorophyll contents and all the test concentrations reduced the total chlorophyll level. However, untreated (raw) distillery effluent stimulated the protein content initially. It has been concluded from-present study that lower concentrations of the raw distillery effluent (1-5%) and treated distillery effluent (1-10%) had stimulated the growth of P. aureus and soil microflora except soil bacteria (inhibited by all the concentration of the raw effluent). However, higher concentrations (raw effluent: 10-20%; treated effluent 15-20%) had toxicity to test parameters.

Alcoholic Beverages↗
PubMed2005

Constructed wetland attenuation of nitrogen exported in subsurface drainage from irrigated and rain-fed dairy pastures.

Nitrogen removal performance is reported for constructed wetlands treating subsurface drainage from irrigated and rain-fed dairy pastures in North Island, New Zealand. Flow-proportional sampling of inflow and outflow concentrations were combined with continuous flow records to calculate mass balances for the wetlands. Drainage flows from the irrigated catchment were 2.5-4 fold higher and N exports up to 5 fold higher per unit area than for the rain-fed catchment. Hydraulic and associated N loadings to the wetlands were highly pulsed, associated with rainfall, soil water status, and irrigation events. Transient pulses of organic nitrogen were an important form of N loss from the rain-fed landscape in the first year, and were very effectively removed in the wetland (> 90%). Median nitrate concentrations of approximately 10 g m(-3) in the drainage inflows were reduced by 15-67% during passage through the wetlands and annual nitrate-N loads by 16-61% (38-31 7 g N m(-2)y(-1)). Generation in the wetlands of net ammoniacal-N and organic-N (irrigated site) partially negated reduction in nitrate-N loads. The results show that constructed wetlands comprising 1-2% of catchment area can provide moderate reductions in TN export via pastoral drainage, but performance is markedly influenced by variations in seasonal loading and establishment/maturation factors.

Animals↗
PubMed2005

[Responses of antioxidation system of Cynodon dactylon to recirculated landfill leachate irrigation].

With pot experiment, this paper studied the membrane lipid peroxidation and the variations of antioxidation system in Cynodon dactylon under recirculated landfill leachate irrigation. The results showed that when irrigated with low dilution ratio (< 25%) leachate, the chlorophyll a/b ratio increased with increasing dilution ratio, membrane permeability and MDA and H2O2 contents were in adverse, and membrane lipid peroxidation was relatively weak. However, with the increasing leachate dilution ratio (> 25%), there existed an obvious negative fect on Cynodon dactylon, i.e., the chlorophyll a/b ratio decreased, while cell membrane permeability and MDA and H2O2 contents increased, which meant that the membrane lipid peroxidation was accelerated. The contents antioxidants AsA, GSH and Car also showed the similar trend, i.e., they increased with increasing leachate dilution ratio when irrigated with low dilution ratio leachate, but decreased under medium or high dilution ratio leachate irrigation. Among three test anti-oxidative enzymes, SOD and POD activities showed a similar change test antioxidants, and POD activity was more sensitive, while CAT activity was on the contrary. The contents test antioxidants and the activities of SOD and POD were negatively and significantly correlated to MDA content, indicating that they might play an important role in preventing Cynodon dactylon from cell membrane lipid peroxdation.

Antioxidants↗