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Sustainable land resource management depends on the good assessment and planning of current landscapes. This may be possible with application of multidisciplinary researches, as this study presented a multidisciplinary approach in a spatial database frame work using Geographic Information System. 'Agroecological zones' concept is used to integrating and characterizing homogenous spatial units. This approach combine theme layers include of available water resources, climate, terrain and soil conditions, associated with land use and settlement patterns. Climatic indices layers, including of growing degree days, aridity index, length of growing period and freezing period were created using the correlation between climatic parameter and digital elevation model. Using this approach the Borujen watershed was divided in 28 'agroecological zones' which defined 3 landscapes or agricultural regions. The most important constraints for developing agriculture in landscape I has topographic, climatic and soil constrains, landscape II has topographic and soil constrains and landscape III has the some limitations of soil. Landscape I and II are much less attractive from an agricultural perspective. Landscape III is suitable for agriculture but, the potential for rainfed cropping system is limited by a lack of growing period during which neither temperature nor moisture is limiting to plant production. In general, the case study of the Borujen watershed indicated that this approach can be used for different scales and adaptive to the particular planning. [ABSTRACT FROM AUTHOR]

Essential oil of Salvia mirzayanii cultivated in Iran was obtained by microwave assisted extraction (MAE) procedures. The essential oil was analysed by capillary gas chromatography using flame ionisation and mass spectrometric detections. The effects of different parameters, such as microwave power, temperature, time and type of solvent on the MAE of Salvia mirzayanii oil were investigated. Results of the two-level fractional factorial design (24−1) based on an analysis of variance demonstrated that only the power, temperature and type of solvent were statistically significant. Optimal conditions for the extraction of essential oils were obtained by using Box–Behnken design. For optimum recovery of essential oil the variables power, temperature and solvent values were 115 W, 50°C and 14 s, respectively. Under the optimised experimental conditions, the extraction yield of microwave assisted extraction was 11.2% (w/w). [ABSTRACT FROM PUBLISHER]

Mixtures of cereals and legumes are used extensively for forage production. Maize (Zea mays) and cowpea (Vigna sinensis) monocultures as well as their mixture in three planting patterns (M1: alternate-row intercrop, M2: within-row intercrop, M1: mixed intercrop) were used to investigate on forage yield as well as the effect of intercropping on maize forage quality. The experiment was carried out as randomized complete block design with three replications. The results showed that intercropping systems had a significant effect on forage dry weight, where dry matter yield was increased by intercropping as compared with maize and cowpea sole crops. It was related with a higher consumption consumption of environmental resources, such as photosynthetically active radiation and soil moisture, by intercropping. Maize forage quality in terms of crude protein was improved by intercropping. It was because of more nitrogen availability for maize in intercropping compared with its sole crop. [ABSTRACT FROM AUTHOR]

Organic and biological fertilizers are considered as a very important source of plant nutrients. A field experiment was conducted during 2017-2018 in paddy soil to investigate the effect of vermicomposting of cattle manure mixture with Azolla and rice straw on soil microbial activity, nutrient uptake, and grain yield under inoculation of N 2 -fixing bacteria. Experimental factors consisted of organic amendments at six levels (vermicomposts prepared from manure (VM); manure + rice straw (VRM); manure + Azolla mixture (VAM); manure + rice straw + Azolla mixture (VRAM); raw manure without vermicomposting (M), and a control) and N 2 -fixing bacteria at three levels ( Azotobacter chroococcum , Azospirillum brasilence , and non-inoculation). The results showed that, vermicompost treatments compared to control and raw manure significantly increased the number and biomass-C of soil microorganisms, urease activity, number of tillers hill -1 , phosphorus (P) and potassium (K) uptake, and grain and protein yield. Inoculation of plants with N 2 -fixing bacteria, especially Azotobacter increased the efficiency of organic amendments, so that the maximum urease activity, soil microbial activity, P and N uptake, and grain yield (4,667 (2017) and 5,081 (2018) kg/h) were observed in vermicompost treatments containing Azolla (VAM and VRAM) under inoculation with Azotobacter . The results of the study suggested that, using an organic source along with inoculation with appropriate N 2 -fixing bacteria for vermicompost has a great effect on enzyme activity, soil biology, nutrient uptake and grain yield has a synergistic interaction on agronomic traits under flooded conditions. Therefore, this nutrient method can be used as one of the nutrient management strategies in the sustainable rice production., Competing Interests: The authors declare there are no competing interests., (©2021 Ghadimi et al.)