scholarly journals Reuse of Pruning Waste from Subtropical Fruit Trees and Urban Gardens as a Source of Nutrients: Changes in the Physical, Chemical, and Biological Properties of the Soil

2021 ◽  
Vol 12 (1) ◽  
pp. 193
Author(s):  
Marino Pedro Reyes-Martín ◽  
Irene Ortiz-Bernad ◽  
Antonio M. Lallena ◽  
Layla M. San-Emeterio ◽  
M. Lourdes Martínez-Cartas ◽  
...  

A field experiment was conducted on the Andalusian coast (Granada, Southern Spain) to study the time course of nutrient release into the soil after the addition of bagged pruning waste from subtropical orchard trees (avocado, cherimoya, and mango) and urban garden waste over three two-year periods. N, P, and K concentrations were greater in the garden waste, whilst avocado and cherimoya pruning waste registered the highest values for Mg. In general, micronutrient contents were low in all waste, especially Cu. Macronutrient release followed a three-phase dynamic: fast initial release, intermediate stabilization, and final increase. Garden waste showed a similar time course in all three trees and released greater concentrations of K and P. The annual decomposition rate factor k was negative for N and Ca in the avocado tree, indicating strong biological activity in this plot. Avocado, cherimoya, and garden waste showed a good microbial degradation, improving soil quality by increasing carbon and nitrogen contents as well as soil microbial activity. As for the mango tree, its special microclimatic conditions appeared to favor waste photodegradation, thus eliminating nutrients that were not incorporated into the soil. Soil enzymatic activities increased in the avocado and cherimoya trees with the addition of all waste. In the mango tree, only an increase in urease was detected after the addition of garden waste. Our results suggest that the time course of organic waste in different subtropical trees grown on similar soils is significantly conditioned by the microclimatic characteristics.

2008 ◽  
Vol 57 (5) ◽  
pp. 727-733 ◽  
Author(s):  
E. Jueschke ◽  
B. Marschner ◽  
J. Tarchitzky ◽  
Y. Chen

In many arid and semi-arid regions, the demand for drinking water and other domestic uses is constantly growing due to demographic growth and increasing standard of living. Therefore, less freshwater is available for agricultural irrigation and new water sources are needed. Treated wastewater (TWW) already serves as an important water source in Israel since more than 40 years and its usage will further be extended. Related to its high loads with nutrients, salts and organic materials its use as irrigation water can have major effects on the soil physical, chemical and biological properties, in the worst case leading to soil degradation. Additional organic matter reaches the soil with the effluent water and soil microbial activity is stimulated. Soil organic carbon (SOC) seems to accumulate in the topsoil and tends to decrease after long-term irrigation with secondary TWW in the subsoil. The amount of dissolved organic carbon increased and the aromaticity of the organic compounds in the soil percolates decreased over the irrigation period. Priming effects, occurring after stimulation of microbial activity by the addition of easily degradable substances, could be found in the soils and were stronger for subsoil (1 m depth).


2017 ◽  
Vol 43 (3) ◽  
pp. 91-96
Author(s):  
Çiğdem Küçük ◽  
Y.Tuba Tekgül

AbstractWith the increase of agricultural production, residues of crop are the main source of organic matter in the soil and they are alternatives to inorganic fertilizers. For this purpose, effects of organic residues (cotton stalk, maize stalk, almond bark) commonly grown in Turkey were investigated for some soil microbial activity in clay soil. In this study, incubation experiment was set up. Five doses (0%, 2%, 4%, 6% and 8%) of organic residues (maize stalks, cotton stalks or almond bark) were applied to soil. Soil microbiological properties of soil samples such as CO2respiration, dehydrogenase and urease activity were determined. According to the results obtained, maize stalk, cotton stalks and almond bark applications increased some soil microbiological activities, such as CO2respiration, dehydrogenase and urease activities according to control soil. Maize stalk in comparison to other residues affects better on the biological properties of the soil. It is determined that enhancing effects of the added organic residues (maize stalk, cotton stalk, almond bark) into the soil were changed according to the type of organic residues, dosage and application terms.


Reproduction ◽  
2000 ◽  
pp. 327-330 ◽  
Author(s):  
RJ Lucas ◽  
JA Stirland ◽  
YN Mohammad ◽  
AS Loudon

The role of the circadian clock in the reproductive development of Syrian hamsters (Mesocricetus auratus was examined in wild type and circadian tau mutant hamsters reared from birth to 26 weeks of age under constant dim red light. Testis diameter and body weights were determined at weekly intervals in male hamsters from 4 weeks of age. In both genotypes, testicular development, subsequent regression and recrudescence exhibited a similar time course. The age at which animals displayed reproductive photosensitivity, as exhibited by testicular regression, was unrelated to circadian genotype (mean +/- SEM: 54 +/- 3 days for wild type and 59 +/- 5 days for tau mutants). In contrast, our studies revealed a significant impact of the mutation on somatic growth, such that tau mutants weighed 18% less than wild types at the end of the experiment. Our study reveals that the juvenile onset of reproductive photoperiodism in Syrian hamsters is not timed by the circadian system.


2016 ◽  
Vol 3 (10) ◽  
pp. 160361 ◽  
Author(s):  
Anne l-M-Arnold ◽  
Maren Grüning ◽  
Judy Simon ◽  
Annett-Barbara Reinhardt ◽  
Norbert Lamersdorf ◽  
...  

Climate change may foster pest epidemics in forests, and thereby the fluxes of elements that are indicators of ecosystem functioning. We examined compounds of carbon (C) and nitrogen (N) in insect faeces, leaf litter, throughfall and analysed the soils of deciduous oak forests ( Quercus petraea  L.) that were heavily infested by the leaf herbivores winter moth ( Operophtera brumata  L.) and mottled umber ( Erannis defoliaria  L.). In infested forests, total net canopy-to-soil fluxes of C and N deriving from insect faeces, leaf litter and throughfall were 30- and 18-fold higher compared with uninfested oak forests, with 4333 kg C ha −1 and 319 kg N ha −1 , respectively, during a pest outbreak over 3 years. In infested forests, C and N levels in soil solutions were enhanced and C/N ratios in humus layers were reduced indicating an extended canopy-to-soil element pathway compared with the non-infested forests. In a microcosm incubation experiment, soil treatments with insect faeces showed 16-fold higher fluxes of carbon dioxide and 10-fold higher fluxes of dissolved organic carbon compared with soil treatments without added insect faeces (control). Thus, the deposition of high rates of nitrogen and rapidly decomposable carbon compounds in the course of forest pest epidemics appears to stimulate soil microbial activity (i.e. heterotrophic respiration), and therefore, may represent an important mechanism by which climate change can initiate a carbon cycle feedback.


1999 ◽  
Vol 19 (6) ◽  
pp. 652-660 ◽  
Author(s):  
Jaroslaw Aronowski ◽  
Ki-Hyun Cho ◽  
Roger Strong ◽  
James C. Grotta

To determine the occurrence and time-course of presumably irreversible subcellular damage after moderate focal ischemia, rats were subjected to 1, 3, 6, 9, or 24 hours of permanent unilateral middle cerebral and common carotid occlusion or 3 hours of reversible occlusion followed by 3, 6, or 21 hours of reperfusion. The topography and the extent of damage were analyzed with tetrazolium staining and immunoblot using an antibody capable of detecting breakdown of neurofilament. Neurofilament proteolysis began after 3 hours in the infarct core but was still incomplete in penumbral regions up to 9 hours. Similarly, tetrazolium-staining abnormalities were observed in the core of 50% of animals after 3 hours of ischemia. At 6 hours of permanent ischemia, infarct volume was maximal, and further prolongation of occlusion to 9 or 24 hours did not increase abnormal tetrazolium staining. In contrast to permanent ischemia and in agreement with the authors' previous demonstration of “reperfusion injury” in this model, prolongation of reperfusion from 3 hours to 6 and 21 hours after 3 hours of reversible occlusion gradually augmented infarct volume by 203% and 324%, respectively. Neurofilament proteolysis initiated approximately 3 hours after ischemia was quantitatively greatest in the core and extended during reperfusion to incorporate penumbra with a similar time course to that of tetrazolium abnormalities. These data demonstrate that, at least as measured by neurofilament breakdown and mitochondrial failure, extensive cellular damage is not present in penumbral regions for up to 9 hours, suggesting the potential for rescuing these regions by appropriate and timely neuroprotective strategies.


Author(s):  
Carolin Schilpp ◽  
Robin Lochbaum ◽  
Peter Braubach ◽  
Danny Jonigk ◽  
Manfred Frick ◽  
...  

AbstractTGF-β1 is a major mediator of airway tissue remodelling during atopic asthma and affects tight junctions (TJs) of airway epithelia. However, its impact on TJs of ciliated epithelia is sparsely investigated. Herein we elaborated effects of TGF-β1 on TJs of primary human bronchial epithelial cells. We demonstrate that TGF-β1 activates TGF-β1 receptors TGFBR1 and TGFBR2 resulting in ALK5-mediated phosphorylation of SMAD2. We observed that TGFBR1 and -R2 localize specifically on motile cilia. TGF-β1 activated accumulation of phosphorylated SMAD2 (pSMAD2-C) at centrioles of motile cilia and at cell nuclei. This triggered an increase in paracellular permeability via cellular redistribution of claudin 3 (CLDN3) from TJs into cell nuclei followed by disruption of epithelial integrity and formation of epithelial lesions. Only ciliated cells express TGF-β1 receptors; however, nuclear accumulations of pSMAD2-C and CLDN3 redistribution were observed with similar time course in ciliated and non-ciliated cells. In summary, we demonstrate a role of motile cilia in TGF-β1 sensing and showed that TGF-β1 disturbs TJ permeability of conductive airway epithelia by redistributing CLDN3 from TJs into cell nuclei. We conclude that the observed effects contribute to loss of epithelial integrity during atopic asthma.


Forests ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 665
Author(s):  
Ladislav Holik ◽  
Jiří Volánek ◽  
Valerie Vranová

Soil proteases are involved in organic matter transformation processes and, thus, influence ecosystem nutrient turnovers. Phytohormones, similarly to proteases, are synthesized and secreted into soil by fungi and microorganisms, and regulate plant rhizosphere activity. The aim of this study was to determine the effect of auxins, cytokinins, ethephon, and chlorocholine chloride on spruce forest floor protease activity. It was concluded that the presence of auxins stimulated native proteolytic activity, specifically synthetic auxin 2-naphthoxyacetic acid (16% increase at added quantity of 5 μg) and naturally occurring indole-3-acetic acid (18%, 5 μg). On the contrary, cytokinins, ethephon and chlorocholine chloride inhibited native soil protease activity, where ethephon (36% decrease at 50 μg) and chlorocholine chloride (34%, 100 μg) showed the highest inhibitory effects. It was concluded that negative phytohormonal effects on native proteolytic activity may slow down organic matter decomposition rates and hence complicate plant nutrition. The study enhances the understanding of rhizosphere exudate effects on soil microbial activity and soil nitrogen cycle.


2012 ◽  
Vol 2012 ◽  
pp. 1-13 ◽  
Author(s):  
A. Marais ◽  
M. Hardy ◽  
M. Booyse ◽  
A. Botha

Different plants are known to have different soil microbial communities associated with them. Agricultural management practices such as fertiliser and pesticide addition, crop rotation, and grazing animals can lead to different microbial communities in the associated agricultural soils. Soil dilution plates, most-probable-number (MPN), community level physiological profiling (CLPP), and buried slide technique as well as some measured soil physicochemical parameters were used to determine changes during the growing season in the ecosystem profile in wheat fields subjected to wheat monoculture or wheat in annual rotation with medic/clover pasture. Statistical analyses showed that soil moisture had an over-riding effect on seasonal fluctuations in soil physicochemical and microbial populations. While within season soil microbial activity could be differentiated between wheat fields under rotational and monoculture management, these differences were not significant.


Sign in / Sign up

Export Citation Format

Share Document