Microbiological Attributes of a Cohesive Yellow Latosol Under Different Land Use Systems

The objective of this study was to evaluate the microbiological attributes of a Cohesive Yellow Latosol. Collections were carried out in three land use systems (LUS). The first, with natural rainforest (NR), the second with sugarcane (SC) cultivated since 2009, and the third under Mimosa cesalpiniifolia (MC) introduced in 1999. Microbiological analyzes were carried out by determining the carbon from microbial biomass, readily mineralizable carbon, microbial respiration, metabolic quotient, total organic carbon, microbial C/total organic C ratio, and occurrence of cellulolytic and ammonifiers microorganisms. Analysis of variance was performed to verify the different measures of microbiological attributes. The variation obtained from CMB was from 3.06 to 4 µg.C.g-1 in NR, 3.02 to 3.92 µg.C.g-1 in MC, and 3.14 to 3.24 µg.C.g-1 in SC. For accumulated CO2, no differences were found between environments, with values ranging from 77 to 55.70 µg.Kg-1 for NR, 80.30 to 49.56 for MC, and 80.30 to 49.56 for SC. qCO2 had no significant effect, and in relation to total organic carbon the forest soil (NR). These results demonstrate that the microbiological attributes of the soil are influenced by cover, environmental standards and soil management, and the sampling time. The forest soil showed superior microbial biomass when compared to other soils. The metabolic control detected a difference between the collection times. For the accumulated CO2 resources, no changes were observed.

Chemical and Spectroscopic Parameters Are Equally Sensitive in Describing Soil Organic Matter Changes After Decades of Different Fertilization

The composition and dynamics of soil organic matter (SOM) are decisive factors in soil quality. In this work, total organic C (Ctot), hot water extractable C (Chwl), and aliphatic and aromatic SOM components detected by Fourier transform infrared (FTIR) spectroscopy were determined to evaluate SOM quantity and quality in soil samples taken between 2004 and 2017 from 13 field experiments established in different soil and climatic conditions of the Czech Republic. In addition, the C pool index (CPI), lability index (LI), C management index (CMI), and SOM decomposition index (DI) were assessed. Treatments were selected as follows: Unfertilized control (Nil), mineral fertilized treatment (NPK), farmyard manured treatment (FYM), and organic and mineral fertilized treatment (FYM+NPK). Both organic and combined fertilization significantly increased soil Ctot, Chwl, CPI, LI, CMI, and labile aliphatic SOM components (FTIRaliph) in most of the experiments compared to unfertilized treatments (p ≤ 0.05). In contrast, the highest content of recalcitrant aromatic SOM components (FTIRarom) and increased DI were determined in majority of unfertilized soils. Our results show that: (1) fertilization regimes increased both labile and total C pools; the highest increase was nearly uniformly observed for NPK+FYM treatment; (2) SOM chemical and FTIR spectral detection had equal sensitivity to the changes; and (3) none of the parameters or indices tested can be used as a stand-alone SOM quality descriptor.

KANDUNGAN C-ORGANIK TANAH DAN TOTAL NITROGEN PADA TANAH VERTISOL YANG TELAH DIBAKAR DAN TIDAK DIBAKAR

The use of fire in agriculture land preparation may result in the change of various soil properties. Therefore, a study was conducted in the village of Oeteta, Kupang to determine soil total organic-C and total nitrogen of burned and unburned Vertisols. Randomized complete block design with two factors was applied. The first factor was burning treatment with two levels: burned and unburned. The second factor was soil depth with three levels: 0-10cm, 11-20cm and 21-30cm; all together made up 54 experimental units. Results showed that in all depths there was no significant difference in total soil organic-C between burned and unburned soils. However total soil organic-C contents in both burning treatments were considered high. Similarly, the was also no significant difference in total soil nitrogen between burned and unburned plots. Total soil N was considered in high and medium levels for burned and unburned soil respectively. In summary, burning does not affect soil total organic-C contents but reduces soil total N contents.

Dolomite and Compost Amendments Enhance Cu Phytostabilization and Increase Microbiota of the Leachates from a Cu-Contaminated Soil

The chemical properties, ecotoxicity, and microbiome of leachates from phytomanaged Cu-contaminated soils were analyzed. The phytomanagement was carried out using Cu-tolerant poplar Populus trichocarpa × deltoides cv. Beaupré and black bent Agrostis gigantea L., aided by soil amendments, i.e., dolomitic limestone (DL) and compost (OM), alone and in combination (OMDL). Plants plus either DL or OMDL amendments reduced in leachates the electrical conductivity, the Cu concentration, and the concentration of total organic C except for the OMDL treatment, and decreased leachate toxicity towards bacteria. Total N concentration increased in the OM leachates. The aided phytostabilization increased the culturable bacteria numbers and the proportion of Cu-resistant bacteria in the leachates, as compared to the leachate from the untreated soil. Phytomanagement also enriched the microbial communities of the leachates with plant beneficial bacteria. Overall, the Cu stabilization and phytomanagement induced positive changes in the microbial communities of the soil leachates.

An Appraisal of Potential for Sowing of Nasturtium officinale into Streams to Mitigate Nutrient Pollution in Eastern Scotland

This study examines a farmer-led initiative to sow watercress (Nasturtium officinale) in field ditches. The objective was to assess the potential of this practice to mitigate summer nutrient loads in rivers. Two ditches—one seeded, the other unseeded—on a mixed-livestock farm in Eastern Scotland were monitored during the spring-summer of 2014–2016. The un-replicated trial design limited statistical analysis. However, changes in N and P concentrations along the two ditches were measured. In the watercress-seeded ditch, N retention of 0.092 g/m2/d (p < 0.001, SE = 0.020) and P retention of 0.0092 g/m2/d (p = 0.001, SE = 0.0028) occurred, while total organic C in the water increased along the ditch. Retention was close to zero for the unseeded ditch. The seeded ditch was also found to have more dry matter production and lower stream temperature. The impact of plastic covering (to increase spring temperature) on vegetation and nutrient removal was also assessed on replicate 5-m sections of the ditches. No significant impact on N and P removal was found; however, the release of C increased significantly in the plastic-covered sections. The rise in air temperature (up to > 30 °C) promoted a greater growth of opportunist species (nettle (Urtica), rush (Juncus), and grasses. These observations were used to make a simple assessment of the potential catchment scale impact of seeding watercress into first and second order streams in the nearby Lunan Water catchment. It was concluded that this could make a significant contribution to the reduction of nutrient loads.

CARBON BALANCE IN ORGANIC CONILON COFFEE INTERCROPPED WITH TREE SPECIES AND BANANA

ABSTRACT Over the last decade, conilon coffee (Coffea canephora) in consortium with wood trees has been established to improve environmental conditions. Little is known about how individual wood trees and banana affect soil quality when intercropped with conilon coffee. The objective of the present study was to evaluate the impacts of intercropping organic conilon coffee with different wood tree species and banana on C balance. Five cultivation systems including conilon coffee monoculture and intercropped with Inga edulis, Gliricidia sepium, BRS Japira banana (Musa sp.), or Bactris gasipaes were studied in a randomized complete block design, with four replicates at the south of Espírito Santo State, Brazil. A primary forest fragment adjacent to the experiment was also evaluated for comparison with the consortium. Samples of topsoil (0 to 10 cm) were collected in 2016 to evaluate the total organic C and total N. Soil temperature and moisture at 0 to 5 cm depth and the CO2 emission were measured monthly over one year. The species planted with the conilon coffee promoted a 5.52% decrease in the soil temperature and a 17% increase in the soil moisture content. They also promoted an increase in annual C balance, especially intercropped with Gliricidia and Inga (4.70 and 3.56 Mg ha-1, respectively), with a substantial increase in the soil total organic C and total N in both systems.

Cropping Practices and Their Drivers in Various Cropping Systems in Peri-urban Areas of Ouagadougou, Burkina Faso

The advantages of urban and peri-urban agriculture in West African cities, namely its contribution to food production, income generation and resorbing unemployment are well reported. In the peri-urban areas, cropping systems and practices are various and may affect differently soil properties. Those systems and practices may be driven by farms socio-economic conditions. Here we conducted a study in 133 peri-urban farms located at the vicinity of the city of Ouagadougou. Farmers were questioned on their cropping practices and soil samples were taken and analyzed for their total organic C, available P and K contents. Principal component analysis allowed to study the variability of the farms considering cropping systems, the cropping practices and the farms socio-economic conditions. We found that in the studied cropping systems up to 60% of the farms variability was explained. Monoculture led to low soil organic carbon while polyculture led to low soil available K. The studied socio-economic conditions of the farms explained up to 60% of the variability in cropping practices.

Chemical indicators for pollution detection in terrestrial and aquatic ecosystems

Background Pollution is objectionable changes in a given ecosystem trailing to potential health hazards. Assessment of pollution levels is continually recognized by several pollution indicators, biological, chemical, and/or physical. Chemical indicators always validate fair information about the evenness between ecosystem components. Results Chemical indicators include pH, quality criterion index, kinetics, oxidation-reduction potential, reactive carbon, total organic C, total residues, dissolved oxygen (DO), chemical oxygen demand (COD), biological oxygen demand (BOD), phosphate (P), nitrogen (N2), anhydrous ammonia (NH3), nitrate (NO3), and copper (Cu2+).

Chemical of Soils With Histic Horizon of Lakes and Riparian of the Savanna, Northern Amazonia, Brazil

The savanna of the northern Amazon of Brazil is an ecosystem that presents lakes and riparian of buriti (Mauritia flexuosa L.) in its landscape. Although these ecosystems are protected by law, they are subject to changes by anthropization in their surrounding areas. The soils of lakes and on the banks of the buriti riparian of the savanna of Boa Vista, Northern Amazonia, are hydromorphic and, although they are important ecosystems for the environmental sustainability, they are little studied. Thus, the purpose of this work was to characterize the chemical composition of these soils and relate the results to the type of anthropization. Samples were collected at the margins of five riparian and three lakes in the 0.0-0.1, 0.1-0.2, 0.2-0.3, 0.3-0.4, and 0.4-0.5 m depth layers. Soil samples, in each environment, were taken from three points equidistant at 100 m. For soil characterization, pH in water, H + Al, Al3+, P, K+, Mg2+, Ca2+, and total organic C (TOC) were determined. The soils of lakes and buriti riparian are of high acidity, low natural fertility, and high toxicity by Al. Buriti riparian presented the highest levels of TOC but were also the environments most susceptible to the effects of anthropization, in which Bom Intento presented values of available P from medium to high by the interference of agricultural activities.

Soil organic matter pools under management systems in Quilombola Territory in Brazilian Cerrado

ABSTRACT The aim of this study was to evaluate the stable and labile fractions of soil organic matter and carbon (C) management index in cultivated areas with conservation and conventional management used by Quilombola farmers in the Goiás state, Brazil. The management systems were studied in the areas of Cerradão: Native Cerrado; Pasture; Conventional grain cultivation; Conservation cultivation of perennial crop; and in the sensu stricto Cerrado: Native Cerrado; Natural pasture; Conventional grain cultivation; Conventional cultivation of perennial crop. The study was considered as observational, with five replicates. Total organic C, fractions of humic substances, labile C and C management index were determined. The Cerradão phytophysiognomy had the highest total organic C values and stable soil organic matter fractions. The native areas had low levels of labile C. The conservation cultivation of perennial crop showed the largest accumulation of total organic C in the different fractions of soil organic matter and the highest rates of C management index.