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1.
Tailing ponds pose environmental hazards,such as toxic metals which can contaminate the surroundings through wind and water erosions and leaching.Various chemical and biochemical properties,together with extractable and soluble metals were measured five years after reclamation of a polluted soil affected by former mining activities.This abandoned mine site contains large amounts of Fe-oxyhydroxides,sulphates,and heavy metals.As a consequence,soils remain bare and the soil organic matter content is low(< 3 g kg 1).Marble waste,pig manure and sewage sludge were applied in 2004.Plant cover and richness,and soil chemical,biochemical and biological parameters were analysed five years later.Results showed that all soil biochemical properties as well as vegetation cover and richness were higher in treated soils than in the untreated contaminated plots(control),although organic matter,pH values and extractable metals concentrations were similar among treatments.Soluble cadmium and zinc were lower in the amended plots than in control.As a general pattern,soil amended with pig manure showed higher values of most biochemical properties compared to sewage sludge application,while the doses did not have a great effect,being only significant for β-glucosidase,phosphodiesterase and arylsulfatase.Significant correlations were found between vegetation cover,richness and soil biochemical properties,suggesting a high interdependence between plant colonization and reactivation of biogeochemical cycles during five years.This study confirms the high effectiveness of an initial application of the amendments tested to initialize the recovery of ecosystems in bare mine soils under Mediterranean semiarid conditions.This research also shows the high sensitivity of certain biochemical properties in order to evaluate soil quality and reactivation of nutrients cycles in reclaimed mine soils.  相似文献   

2.
碱稳定污泥污水对土壤可提取有机碳和铜的影响   总被引：4，自引：1，他引：4  
An incubation experiment was conducted to evaluate the potential for water contamination with sludge-derived organic substances and copper following land application of alkaline-stabilised sewage sludge. Two contrasting sludge-amended soils were studied. Both soils were previously treated with urban and ruralalkaline biosolids separately at sludge application rates of 0, 30 and 120 t ha-1 fresh product. The air-driedsoil/sludge mixtures were wetted with distilled water, maintained at 40 % of water-holding capacity and equilibrated for three weeks at 4 ℃ before extraction. Subsamples were extracted with either distilled wateror 0.5 mol L-1 K2SO4 solution. The concentrations of organic C in the aqueous and chemical extracts were determined directly with a total organic carbon (TOC) analyser. The concentrations of Cu in the twoextracts were also determined by atomic absorption spectrophotometry The relationship between the two extractable organic C fractions was examined, together with that between extractable organic C concentration and extractable Cu concentration. Application of alkaline biosolids increased the concentrations of soil mobile organic substances and Cu. The results are discussed in terms of a possible increase in the potential for leaching of sludge-derived organics and Cu in the sludge-amended soils.  相似文献   

3.
The recycling of suitable organic wastes can enhance soil fertility via effects on soil physical, chemical and biological properties. To compare the effects of digested (DS), thermally dried (TDS) and composted dewatered (CDS) sewage sludge on soil microbiological properties, an experiment was conducted at field sites for more than one year (401 d) when applied to two Mediterranean degraded soils (loam and loamy sand soils). All three types of sewage sludge had a significant effect on measured parameters. I...  相似文献   

4.
A glasshouse pot experiment was conducted to study changes in the solubility of copper and zinc in the soil-plant system following heavy application of sewage sludge and partial sterilisation of the sludge/soil mixture. A slightly acid sandy loam was mixed with alkaline stabilised and composted urban sewage sludge solids (Agri-Soil, 180 t hm-2), and the soil/sludge mixture was-irradiated (10 kGy). The contrasts without the application of sewage sludge and-irradiation were also included in the experiment. Perennial ryegrass (Lolium perenne cv. Magella) was grown on irradiated and unirradiated soils for 50 days. Soil solution samples were obtained using soil suction samplers immediately before plant transplantation and every ten days thereafter. The soil solution samples were used directly for determination of Cu and Zn, toget her with pH, electrical conductivity (EC) and absorbance at wavelength 360 nm (A360). Applicat ion of Agri-Soil led to a substantial increase in dissolved Cu and a significant decrease in dissolved Zn in the soil solution and these effects were accompanied by increased soil solution pH, EC and A360. The alkaline sludge product (Agri-Soil) in combination with-irradiation also led to a pronounced elevation of Cu and A360 but a marked decline in EC, indicating an increase in dissolved organic compounds and a decrease in the ionic strength of the soil solution. The dissolved Cu and Zn, EC and A360 usually decreased while the pH increased after plant grow th for 50 days.  相似文献   

5.
An incubation experiment was conducted to investigate the microbial biomass associated Cu in four contrasting soils to which an alkaline stabilised sewage sludge cake was applied. The organisms of sludge-amended and control soils were killed using γ-irradiation technique, and the aqueous and acid-extractable Cu concentrations were determined. Addition of the sludge product increased significantly the concentration of both the aqueous and dilute HOAc-extractable Cu in all the irradiated soils compared to the non-sterilised sludge/soil mixtures, but the increase was more pronounced in the dilute acid-extractable Cu, indicating thatthe Cu rendered extractable in water and dilute acetic acid by γ-irradiation existed in the both soil liquidand solid phases. The additional increase in extractable Cu following the biocidal treatment is likely to bedue to release of Cu from the same fraction of soil microbial biomass.  相似文献   

6.
There are many remediation techniques for organic contaminated soils,but relatively few of them are applicable to trace elementcontaminated soils.A field experiment was carried out to investigate assisted natural remediation（ANR） of an acid soil contaminated by As,Cd,Cu,Zn and Pb using one inorganic amendment,sugar beet lime（SL）,and two organic amendments,biosolid compost（BC）and leonardeite（LE）.The experiment was arranged in a completely randomized block design with four treatments in three replicates:1) a non-amended control（NA）;2) SL amended at 30 Mg ha-1 year-1;3) BC amended at 30 Mg ha-1 year-1 and 4) LE amended at 20 Mg ha-1 year-1 plus SL amended at 10 Mg ha-1 year-1（LESL）.The amended plots received two doses of each amendment（DO2）:one in October 2002 and another in October 2003.The plots were then divided in half into two subpolts and one subplot received another two doses of the same amendments（DO4） in October 2005 and October 2006.In 2011,the pH values of the amended soils were greater than that of the NA soil,with the SL-amended soil showing the highest pH.Total organic carbon（TOC） was also greater in the amended soil,and greater with DO4 than with DO2.Amendments reduced the concentrations of 0.01 mol L-1 CaCl2-extractable Cd,Cu and Zn,especially in the SL-amended soil.Plant cover of colonizing vegetation was enhanced by amendments,but was independent of amendment doses.Changes in soil properties from 2003 to 2011 showed that the first amendment application of DO2 caused a high differentiation between all the amendment treatments and the NA treatment.After the second application of DO2,soil pH and TOC continued increasing slowly.Further two applications of amendments（DO4） caused differences only in the organic treatments.Plant cover increased over time in all the treatments including NA.It could be concluded that the slow and steady natural remediation of this soil could be enhanced by amendment application（ANR）.  相似文献   

7.
The quantification of phosphorus(P) in bulk soil and P distribution in different size fractions of water-stable aggregates(WSAs)are important for assessing potential P loss through runoff. We evaluated available and total P distribution within WSAs of a sitty clay to clay soil in a long-term fertility experiment of a rice-wheat cropping system in India. Surface soil samples were collected from seven plots amended with NPK fertilizers in combination with or without organic amendments, farmyard manure(FYM), green manure(GM), and paddy straw(PS). The plot with no NPK fertilizers or organic amendments was set as a control. The soil samples were separated by wet sieving into four soil aggregate size fractions: large macroaggregates( 2.0 mm), small macroaggregates(0.25–2.0 mm), fine microaggregates(0.05–0.25 mm), and a silt + clay-sized fraction( 0.05 mm). Structural indices were higher in the soil receiving organic amendments than in the soil receiving inorganic fertilizer alone. Organically amended soil had a higher proportion of stable macroaggregates than the control and the soil receiving inorganic fertilizer alone, which were rich in microaggregates. Total and available P contents within WSAs were inversely related to the aggregate size, irrespective of treatment. The distribution of available and total P in the soil aggregate size fraction was as follows: silt + clay-size fraction small macroaggregates fine microaggregates large macroaggregates. Within a size class, aggregate-associated available and total P contents in the organically amended soil were in the following order: FYM PS ≥ GM. The available P content of the microaggregates( 0.25 mm) was 8-to 10-times higher than that of the macroaggregates( 0.25 mm), and the total P content of the microaggregates was 4-to 5-times higher than that of the macroaggregates. Cultivation without organic amendments resulted in more microaggregates that could be checked by the application of organic amendments such as FYM and GM, which increased the proportion of water-stable macroaggregates by consolidating microaggregates into macroaggregates.  相似文献   

8.
A pot experiment was conducted with multi-metal (Pb, Cd, Cu, and Zn) contaminated acidic soil to investigate changes in available metal burden resulting from the application of industrial wastes (fly ash and steel slag). The efficiency of amendments-induced metal stabilization was evaluated by diffusive gradients in thin films (DGT), sequential extraction, and plant uptake. The stability of remediation was assessed by an acidification test and by chemical equilibrium modeling. Addition of fly ash (20 g kg-1 ) and steel slag (3 g kg-1 ) resulted in similar increase in soil pH. Both amendments significantly decreased the concentrations of metals measured with DGT (C DGT) and the metal uptake by Oryza sativa L. Significant correlations were found between C DGT and the concentration of a combination of metal fractions (exchangeable, bound to carbonates, and bound to Fe/Mn oxides), unraveling the labile species that participate in the flux of metal resupply. The capability of metal resupply, as reflected by the R (ratio of C DGT to pore water metal concentration) values, significantly decreased in the amended soils. The C DGT correlated well with the plant uptake, suggesting that DGT is a good indicator for bioavailability. Acidification raised the extractable metal concentration in amended soil but the concentration did not return to the pre-amendment level. Equilibrium modeling indicated that the soil amendments induced the precipitation of several Fe, Al and Ca minerals, which may play a positive role in metal stabilization. Chemical stabilization with alkaline amendments could be an effective and stable soil remediation strategy for attenuating metal bioavailability and reducing plant metal uptake.  相似文献   

9.
Environmental pollution caused by metals, radionuclides and organic pollutants affects quality of the biosphere: soil, water and air.Currently, great efforts have been made to reduce, remove or stabilize contaminants in polluted sites. There has been increasing interest in phytoremediation—the use of plants to reduce concentration of pollutants or to render them harmless. This paper provides a brief review of recent progress in the research and practical application of phytoremediation techniques. Improvements in phytoremediation due to utilization of organic amendments, namely, agro- and industrial wastes(such as sugar beet residue, composted sewage sludge or molasses), biochar, humic substances, plant extracts and exudates are discussed, as well as their influences on soil structure and characteristics, plants growth and bioavailability of pollutants. Both plant-assisted phytoremediation and the use of natural materials in the absence of remediating plant are believed to be cost-effective and environmentally friendly approaches for soil cleanup. However,the characterization and quantification of a range of natural materials used in phytoremediation are essential in order to implement these approaches to practice.  相似文献   

10.
Mine tailing soils created from the copper extraction in Touro Mine (Northwest Spain) are very degraded both physically and chemically. Three plots in this mine tailing were amended with Technosols in different proportions in each one to know if this mixture improved the physico-chemical characteristics of the mine soil and contaminated it with heavy metals. The Technosols were made of organic wastes, including mussel residues, wood fragments, sewage sludges and paper mill ashes. An unamended area was used as a control soil. Pseudototal and diethylenetriaminepentaacetic acid (DTPA)-extractable contents of Al, Cr, Cu, Fe, Mn, Ni, Pb and Zn were determined in soil samples. The untreated soil had significant limitations for vegetation growth. All the Technosols improved the properties of the mine soil by increasing organic carbon and pH value, but they added Ni, Pb or Zn to the soil. It is advisable to check whether the heavy metal concentrations of the wastes are hazardous or not before adding to soils. It is also necessary to study the effect of these wastes over time and in more areas to conclude if they are actually favourable to restore degraded mine soils.  相似文献   

11.
Sluszny  C.  Graber  E. R.  Gerstl  Z. 《Water, air, and soil pollution》1999,115(1-4):395-410
Fresh amendment of soil with sewage sludge and composted sewage sludge resulted in increased sorption of three s-triazine herbicides: atrazine, ametryn and terbuthylazine. The extent of increased sorption (as evaluated by sorption coefficients Kd or Kf) was a function of soil type, such that sorption in amended organic carbon-poor soil (0.4% OC) was more enhanced than in amended organic carbon-rich soil (1.55% OC). Despite significant differences between the organic amendments in terms of humic and fulvic acid content, humin content, soluble organic matter content, total organic matter content, and H/C and O/C atomic ratios, organic matter composition had no discernible effect on either sorption distribution coefficients or on isotherm linearity in amended soils. Soils amended with composted sludge had the same sorption potential as did soils amended with the analogous uncomposted sludge. After incubating soil-sludge mixtures for a year at room temperature, organic matter content decreased to original pre-amendment levels. Sorption coefficients for the three compounds similarly decreased to initial pre-amendment values. Organic carbon normalized sorption coefficients (Koc) were essentially identical in the soils, amended soils, and incubated amended soils, indicating that sludge and compost derived organic matter does not have a significantly different sorption capacity as compared with the original soils, despite compositional differences.  相似文献   

12.
The benefits of adding composted organic materials to soils to enhance carbon storage could be countered by the mobilisation of some harmful pollutants commonly found in frequently degraded urban soils. Therefore non-composted materials could be a safer option. In the present study, carbon and trace element fluxes in soil pore water were studied in response to the surface mulch addition and the incorporation into an urban soil of greenwaste compost versus two non-composted amendments; a woody oversize material and biochar following inoculation with the vertical burrowing earthworm Lumbricus terrestris. The aim was to establish (i) to what extent the non-composted amendments impacted on mobility of soluble trace elements in the soil, compared to the composted amendment, and (ii) if/how this was regulated by earthworm activity.Both composted and non-composted amendments enhanced dissolved organic carbon (DOC) in soil pore water to ∼100-300 mg l−1 in the upper depth of the soil profile above which they were applied as a mulch and similarly within the mesocosms in which they were mixed. Dissolved organic carbon, dissolved nitrogen (DTN) and trace metals, especially Cu and Pb, where enhanced to the greatest extent by greenwaste compost, because of strong co-mobilisation of metals by DOC. Biochar enhanced As and Cu mobility in the field profile and, additionally Pb in the mesocosms, with no effect on Cd. The woody, oversize amendment neither greatly increased DOC nor As, Cu, Pb or Zn mobility although, unlike the other amendments, earthworms increased DOC and Cd mobility when soils were amended with this material.This study concludes that non-composted amendments had a lower impact on DOC and thus trace element co-mobility than the composted greenwaste in this urban soil, whilst the general influence of earthworms was to reduce DOC and hence associated trace element mobility. In wider environmental terms the addition of non-composted materials to some urban soils, versus composted greenwaste could reduce the risk of mobilising potentially harmful elements, whilst usefully improving soil quality.  相似文献   

13.

Purpose

The aim of this study was to evaluate in the medium term (5 years) the effect of two organic amendments, which were spiked to a degraded soil as a strategy for bioremediation, on the amount and characteristics of soil humic acids (HAs) and their ability to associate with certain extracellular enzymes.

Materials and methods

Soil samples were collected in an experimental field where 5 years earlier, a mixture of the organic fraction of household waste and sewage sludge (2:1 ratio), both composted (composted residue, CR) and non-composted (fresh residue, FR), had been added in triplicate at rates equivalent to 1 % (D1) and 3 % of organic carbon (D2) to 30-m2 plots as a strategy for degraded soil restoration. Humic substances (HSs) and HAs were extracted from the collected soil samples and submitted to chemical, biochemical, spectroscopic (FTIR), and chemical-structural (CPMAS 13C NMR) analyses.

Results and discussion

After 5 years, the amended soils showed significantly higher HS and HA content than did the control soil, and the differences with respect to the control were greater with compost addition than with FR addition. The HA from the amended soils had higher H, N, and S contents than the HA from the non-amended soil in addition to a lower oxygen content and lower O/C ratio values. Furthermore, the FTIR spectra of the HA from the amended soils showed a higher absorption intensity in bands corresponding to aliphatic and amide-carboxylic groups and polysaccharide structures and a lower absorption intensity in bands corresponding to carbonyls and carboxylic groups than the HA from the control. These results were confirmed by 13C-NMR spectra, which showed a clear increase of aliphatic compounds in the HA from the amended soils with respect to the HA from the control. HA spectra were not greatly influenced by the maturity of the amendment or by the application dose.

Conclusions

In general, the addition of organic amendments increased the quantity of enzymes immobilized in the humic colloid. Furthermore, the addition of the composted residues favored to a greater extent the immobilization of the abovementioned enzymes, which represent a biological reservoir in the soil. This is of great importance since these enzymes possess functional capacity even when the soils are under conditions that are stressful or unfavorable for microbial life. An increase in the quantity of immobilized enzymes such as that observed in amended soils supposes an important improvement in soil quality.
  相似文献   

14.
The application of organic amendments on soils poor in organic matter (OM) can improve long-term soil fertility, but may also enhance the mineralization of native soil organic matter. Three organic amendments, compost, sewage sludge and horse manure used by urban market gardeners in Dakar, Senegal were analyzed for their OM maturity. Their fate was evaluated in a 45-d agronomic trial in a sandy Arenosol with lettuce. In each case, water-extractable organic matter (WEOM) and humic-like substances (HLS) were isolated from raw amendments and amended soils, and characterized using ultraviolet-visible (UV/Vis) spectroscopy. Results highlighted the general more aromatic character of HLS and WEOM fractions extracted from compost compared to the other two amendments. When applied to soils, however, these differences were not clearly observed. The aromaticity and humification degree of the labile fraction (WEOM) increased with depth in the first 30 cm for all amendments. This indicated the high lixiviation rates that fresh OM underwent in the studied sandy soil. Finally, a statistical analysis of the results was able to discriminate between surface and deeper horizons and between amended- and non-amended soil samples. Spectroscopic indices showed indeed strong increase/decrease with depth linked with the mineralization/humification processes that the fresh OM from amendments underwent during the 45 d of the agronomic trial. This study highlights the potential of spectroscopic techniques to study agricultural amendment organic matter fractions and their fate in soils.  相似文献   

15.
The use of organic amendments requires an adequate control of the chemical quality of their humic acid (HA)-like fractions and of the effects that these materials may have on the status, quality, chemistry and functions of native soil HAs. In this work, the compositional, functional and structural properties of the HA-like fractions isolated from a liquid swine manure (LSM), a municipal sewage sludge (SS), and two municipal solid waste composts (MSWCs) were evaluated in comparison to those of HAs isolated from three unamended soils and from the corresponding soils amended with LSW, SS, and MSWC at various rates in three field plot experiments conducted in Minnesota, USA. With respect to the unamended soil HAs, the HA-like fractions of the three amendments featured a greater aliphatic character, a marked presence of proteinaceous, S-containing and polysaccharides-like structures, an extended molecular heterogeneity, small organic free radical contents and a small degree of humification. The MSWC-HAs featured a larger degree of humification than LSM-HA and SS-HA. The three amendments affected in different ways and by various extents the compositional, structural and functional properties of soil HAs depending upon the nature, origin and application rate of the amendment. In general, the data obtained suggested that proteinaceous, S-containing and aliphatic structures contained in HA-like fractions of organic amendments were partially incorporated into native soil HAs.  相似文献   

16.

Purpose

We investigate the coevolution of soil organic matter (SOM) and soil properties in a semiarid Mediterranean agroecosystem, as well as the 1-year evolution of the different pools of soil organic and inorganic carbon and their influence on soil respiration after the application of a single high dose of three different organic amendments.

Material and methods

We applied a single high dose (160?Mg?ha?1 in dry weight (DW)) of three types of organic amendments: aerobically digested sewage sludge (AE), anaerobically digested sewage sludge (AN), and municipal solid waste compost (MSWC), in a calcareous Mediterranean soil. The study area is located in the southeast of Madrid (Spain), characterized by a Mediterranean climate with a marked seasonal and daily contrast. We analyzed different forms of soil organic and inorganic carbon and soil respiration rates. The measurements have been performed quarterly for 1?year.

Results and discussion

The results showed that the coevolution of SOM and soil largely depends on the origin and composition of the organic amendments used. The AN sludge affected the soil chemistry more. The organic matter (OM) provided by AE treatments underwent more intense mineralization processes than AN, with the OM from MSWC being more stable. This behavior could be explained by the different pools of carbon involved in each case. The treatments contributed differently to soil respiration rates following the sequence: AE > AN > MSWC. The application of organic amendments in calcareous Mediterranean soils also modified the inorganic carbon pools.

Conclusions

SOM and soil coevolution after organic amendments application depends on the origin and chemical composition of the inputs. The decision-making process of urban organic waste application with regard to agricultural policy must take into account the different behavior in soil of the different types of amendments.  相似文献   

17.
《Geoderma》2007,137(3-4):497-503
Soil amendment with sewage sludge (SS) from municipal wastewater treatment plants is nowadays a common practice for both increasing soil organic matter and nutrient contents and waste disposal. However, the application of organic amendments that are not sufficiently mature and stable may adversely affect soil properties. Composting and thermal drying are treatments designed to minimize these possible deleterious effects and to facilitate the use of SS as a soil organic amendment. In this work, an arid soil either unamended or amended with composted sewage sludge (CSS) or thermally-dried sewage sludge (TSS) was moistened to an equivalent of 60% soil water holding capacity and incubated for 60 days at 28 °C. The C–CO2 emission from the samples was periodically measured in order to study C mineralization kinetics and evaluate the use of these SS as organic amendments. In all cases, C mineralization decreased after the first day. TSS-amended soil showed significantly higher mineralization rates than unamended and CSS-amended soils during the incubation period. The data of cumulative C–CO2 released from unamended and SS-amended soils were fitted to six different kinetic models. A two simultaneous reactions model, which considers two organic pools with different degree of biodegradability, was found to be the most appropriate to describe C mineralization kinetics for all the soils. The parameters derived from this model suggested a larger presence of easily biodegradable compounds in TSS-amended soil than in CSS-amended soil, which in turn presented a C mineralization pattern very similar to that of the unamended soil. Furthermore, net mineralization coefficient and complementary mineralization coefficient were calculated from C mineralization data. The largest losses of C were measured for TSS-amended soil probably due to an extended microbial activity. The results obtained thus indicated that CSS is more efficient for increasing total organic C in arid soils.  相似文献   

18.
《Applied soil ecology》2002,19(2):147-160
Field experiments were conducted to examine the effects of organic and synthetic soil fertility amendments on soil microbial communities and soil physical and chemical properties at three organic and three conventional vegetable farms in Virginia and Maryland in 1996 and 1997. Two treatments, including either an alternative organic soil amendment (composted cotton-gin trash, composted yard waste, or cattle manure) or synthetic soil amendment (fertilizer) were applied to three replicated plots at each grower field location. Production history and time affected propagule densities of Trichoderma species which remained higher in soils from organic farms. Propagule densities of Trichoderma species, thermophilic microorganisms, and enteric bacteria were also detected in greater numbers in soils amended with alternative than synthetic amendments, whereas propagule densities of Phytophthora and Pythium species were lower in soils amended with alternative than synthetic fertility amendments. Concentrations of Ca, K, Mg, and Mn were higher in soils amended with alternative than synthetic fertility amendments. Canonical correlations and principle component analyses indicated significant correlation between these soil chemical factors and the biological communities. First-order canonical correlations were more negative in fields with a conventional history, and use of synthetic fertilizers, whereas canonical correlations were more positive in fields with a history of organic production and alternative soil amendments. In the first year, yields of corn or melon were not different in soil amended with either synthetic or organic amendments at four of six farms. In the second year, when all growers planted tomatoes, yields were higher on farms with a history of organic production, regardless of soil amendment type. Alternative fertility amendments, enhanced beneficial soil microorganisms reduced pathogen populations, increased soil organic matter, total carbon, and cation exchange capacity (CEC), and lowered bulk density thus improving soil quality.  相似文献   

19.
The incorporation of organic amendments from pruning waste into soil may help to mitigate soil degradation and to improve soil fertility in semiarid ecosystems. However, the effects of pruning wastes on the biomass, structure and activity of the soil microbial community are not fully known. In this study, we evaluate the response of the microbial community of a semiarid soil to fresh and composted vegetal wastes that were added as organic amendments at different doses (150 and 300 t ha−1) five years ago. The effects on the soil microbial community were evaluated through a suite of different chemical, microbiological and biochemical indicators, including enzyme activities, community-level physiological profiles (CLPPs) and phospholipid fatty acid analysis (PLFA). Our results evidenced a long-term legacy of the added materials in terms of soil microbial biomass and enzyme activity. For instance, cellulase activity reached 633 μg and 283 μg glucose g−1 h−1 in the soils amended with fresh and composted waste, respectively. Similarly, bacterial biomass reached 116 nmol g−1 in the soil treated with a high dose of fresh waste, while it reached just 66 nmol g−1 in the soil amended with a high dose of composted waste. Organic amendments produced a long-term increase in microbiological activity and a change in the structure of the microbial community, which was largely dependent on the stabilization level of the pruning waste but not on the applied dose. Ultimately, the addition of fresh pruning waste was more effective than the application of composted waste for improving the microbiological soil quality in semiarid soils.  相似文献   

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