Characterizing selected soil attributes of different land-use management to assess reforestation benefits of deforested riparian buffers

Introduction:The information available on the sensitivity of soil biotic and abiotic attributes,which can be used to track the impact of reforestation in riparian buffers,is often insufficient to refine management practices and convince stakeholders of the benefits of reforestation.Methods:In this study,conducted in Victoria,Australia,the changes in soil biotic and abiotic attributes,organic carbon(OC),mineral nitrogen(MN),total dissolved solutes(TDS)and pH were characterised to assess the impact of land-use change from bare riparian(BR)to reforested riparian(RR).Additionally,the benefits of revegetating a deforested creek bank with regard to salinity abatement and C-sequestration potentials were assessed.Results:The TDS depletion in the RR strips varied spatiotemporally from 65 to 169 mg/L,the net OC deposition from 16 to 19 g C/kg soil and MN deposition from 1.2 to 2.1 g N/kg soil,respectively.Additionally,the net changes in pH from alkaline to near neutral condition varied by 0.4 to 1.0 pH units.Approximately 30%to 60%of the net OC depletion after deforestation was redeposited under RR over 3 to 6 years.The TDS depletion after land-use changed from BR to RR ranged from 15 to 32%over 3 to 6 years.Conclusion:The soil attributes OC,MN and TDS characteristics under different land-use practices varied spatiotemporally.This information may be useful to convince stakeholders to undertake reforestation of creek banks for salinity abatement,and that change in land-use has the potential to increase C sequestration at a farm scale.

Germination characteristics and diversity of soil seed banks and above-ground vegetation in disturbed and undisturbed oak forests

The destruction of natural ecosystems is an important issue in many parts of the world. In the west of Iran, a vast area of the Zagros Mountain range is covered by typical vegetation including several rare plant species, of which many are currently considered endangered by anthropogenic activities. Despite the important role of soil seed banks to help conserve these degraded plant communities, the floristic studies in the Zagros forests have only focused on aboveground vegetation. In this study, the characteristics of soil seed banks and above-ground vegetation were examined at two forest sites: an undisturbed control(Un) and a disturbed(D) site. The objectives of this study were 1) to investigate the diversity of above-ground vegetation and soil seed banks in disturbed and undisturbed forests, 2) to examine the soil properties and the germination characteristics of the soil seed bank in disturbed and undisturbed oak forests and 3) to estimate the potential of soil seed banks in the restoration of disturbed sites. The results show that soil properties between Un and D sites were significantly different with higher values of pH, NH 4-N, N tot, CEC, OC, clay and canopy percentage in the Un site than in the D site. The Simpson diversity, Margalef richness and evenness indices differed significantly between sites, either for the soil seed banks or the above-ground vegetation. After a period of 26 weeks, the germination speed and the mean daily number of germinants were significantly different between Un and D sites. Without other conservation measures, soil seed banks alone cannot result in a full recovery after severe disturbances in the oak forests of Zagros.

Determination of soil physicochemical attributes in farming sites through visible,near-infrared diffuse reflectance spectroscopy and PLSR modeling

Introduction:An accurate and reliable detection of soil physicochemical attributes(SPAs)is a difficult and complicated issue in soil science.The SPA may be varied spatially and temporally with the complexity of nature.In the past,SPA detection has been obtained through routine soil chemical and physical laboratory analysis.However,these laboratory methods do not fulfill the rapid requirements.Accordingly,diffuse reflectance spectroscopy(DRS)can be used to nondestructively detect and characterize soil attributes with superior solution.In the present article,we report a study done through spectral curves in the visible(350–700 nm)and near-infrared(700–2500 nm)(VNIR)region of 74 soil specimens which were agglomerated by farming sectors of Phulambri Tehsil of the Aurangabad region of Maharashtra,India.The quantitative analysis of VNIR spectrum was done.Results:The spectra of agglomerated farming soils were acquired by the Analytical Spectral Device(ASD)Field spec 4 spectroradiometer.The soil spectra of the VNIR region were preprocessed to get pure spectra which were the input for regression modeling.The partial least squares regression(PLSR)model was computed to construct the calibration models,which were individually validated for the prediction of SPA from the soil spectrum.The computed model was based on a correlation study between reflected spectra and detected SPA.The detected SPAs were soil organic carbon(SOC),nitrogen(N),soil organic matter(SOM),pH values,electrical conductivity(EC),phosphorus(P),potassium(K),iron(Fe),sand,silt,and clay.The accuracy of the PLSR model-validated determinant(R^(2))values were SOC 0.89,N 0.68,SOM 0.93,pH values 0.82,EC 0.89,P 0.98,K 0.82,Fe 0.94,sand 0.98,silt 0.90,and clay 0.69 with root mean square error of prediction(RMSEP)3.51,4.34,2.66,2.12,4.11,1.41,4.22,1.56,1.89,1.97,and 9.91,respectively.According to the experimental results,the VNIR-DRS was better for detection of SPA and produced more accurate predictions for SPA.Conclusions:In conclusion,the methods examined here offered rapid and novel detection of SPA from reflectance spectroscopy.The outcome of the present research will be apt for precision farming and decision-making.