The impacts of long-term intensive agriculture on the Vertisol properties in a calcareous region

Abstract

Morphological, physicochemical, and mineralogical properties of Vertisols (Chromic Calcixererts, Typic Haploxererts, and Typic Calcixererts) influenced under farming practices and adjoining uncultivated soils were investigated in order to contribute to the understanding of changes derived by intensive cultivation (over five decades). The study revealed that A-horizon thickness enhanced from 20 cm in the uncultivated soil to 30 cm in the cultivated soil for Typic Haploxererts and Typic Calcixererts. Under cropping, calcium carbonate contents decreased (a drop of 10 to 53%) reflecting accelerated leaching and/or erosion by cultivation. For most of the studied soils, a pronounced depletion was recorded at values of soil organic carbon (23-64%), soluble cations (4-96%), and exchangeable cations (9-42%) after cropping. A considerable positive change in soil quality was observed with cultivation as recorded by a declining trend in soil electrical conductivity (a drop of 12 to 17%) and exchangeable sodium percentage (a drop of 9 to 12%). On average, the concentration of free and crystalline Fe oxides progressively increased for Chromic Calcixererts and Typic Calcixererts following intensive cultivation. Cropping operations considerably promoted the alteration of illite and chlorite minerals into expandable minerals linked with changes in soil physicochemical properties mainly the increase in cation exchange capacity. Land productivity index (LPI), evaluated based on parametric approach, suggested that Chromic Calcixererts and Typic Haploxererts highlighted a decreasing trend in LPI values (a drop of 5 to 7%) while Typic Calcixererts manifested an increasing pattern in the index (a rise of 13%) with long-term intensive cropping.

Residual effects of pipeline construction on agricultural soils of the Canadian prairie

“…Classification systems that function like the LSRS can track soil quality following disturbance and provide objective evidence of recovery. A land productivity index applied in central Iran found that two groups of Vertisols displayed reduced productivity indices while a third group showed an improved index in response to the long-term effects of cropping practices (Rezapour et al, 2015). Three of five reclaimed coal mine sites in the semi-arid western United States had higher land capability compared to references while two of five had reduced land capability (Schafer, 1984).…”

Gejala Produktivitas Rendah dan Pertanian Degeneratif

“…Faktor teknologi dapat menyebabkan degenerasi agroekosistem seperti penggunaan bahan kimia dan pengolahan tanah yang tidak ramah lingkungan, sistem monokultur jangka panjang tanpa rotasi, serta kurangnya pengembangan dan penataan varietas atau klon. Pertanian monokultur intensif (pengolahan tanah dan input) dan terus-menerus dalam jangka panjang akan menunjukkan keadaan agroekosistem degeneratif sebagai akibat dari penurunan kualitas lahan seperti penurunan kandungan bahan organik, kation terlarut, dan kapasitas tukar kation (Rezapour et al 2015). Pertanaman kentang intensif yang terus-menerus dalam jangka panjang menunjukkan penurunan produktivitas seperti dilaporkan oleh Saini dan Grant (1980) antara lain akibat erosi yang tinggi jika guludan searah kelerengan (Henny et al 2011).…”

Effects of irrigation and cultivation on the chemical indices of saline–sodic soils in a calcareous environment

“…Land productivity is the term given to the capability of land to perform productivity potential based on an evaluation of its physical, chemical, and biological characteristics. This index is greatly important in the management decisions on to accept a type and intensity of land use permanently without long-time degradation (Rezapour et al 2015).…”