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Analysis of elevation-aspect effect showed that aspect had a great influence on FVC at the elevation no more than 1000 m and more than 1500 m in bare Pisha sandstone and sand-covered Pisha sandstone areas, respectively. The aspect of soil-covered Pisha sandstone had a small influence on FVC, its influence was relatively large at 1200-1300 m. When the slope of Pisha sandstone area was no more than 15°, the slope-aspect effect of FVC was not obvious. When the slope was more than 25°, FVC of shady and semi-shady slope in bare and sand-covered Pisha sandstone areas was larger than that of sunny and semi-sunny slopes. For soil-covered Pisha sandstone, when the slope was more than 15°, FVC of semi-shady and semi-sunny slopes was larger than that of shady and sunny slopes.Biochar is a potential source for improving soil fertility and crop yield by enhancing phosphorus (P) availability. But the information on quantitative effect of biochar addition on soil P availability is still limited. To address this query, we conducted a meta-analysis with 507 data from 95 eligible literature. The results showed that irrespective of biochar characters (raw material, CN ratio, pyrolysis temperature, application rate), soil characteristics (texture, pH, organic carbon content), and fertilizer application, biochar addition significantly improved soil available P content by 57.6%. Meanwhile, biochar addition promoted P utilization of crops. The response ratios of plant P concentration to biochar addition were generally lower than those of soil available P. The average response ratio of plant P concentration was 30.6%. The biochars, derived from livestock manure, low-temperature pyrolysis, with lower CN ratio, alkaline, or higher application rate, were more effective to improve soil available P content and plant P concentration in sandy and loamy soils. For main enzymes involved in P cycle, biochar addition increased activity of alkaline phosphatase (2.8%) but decreased the acid phosphatase activity (17.8%). Overall, biochar addition positively affects soil available and plant P concentration, but has a minute effect on soil phosphatase. The improvement of soil P availability might mainly be ascribed to a great amount of active P fractions in biochar itself.As an area suitable for the plantation of Camellia oleifera, Jiangxi had a low degree of development and utilization. Evaluating its potential productivity and resource utilization efficiency could provide reference for optimizing C. oleifera planting division, increasing yield and rationally utilizing land resources. Natural production potential of C. oleifera in Jiangxi was estimated by stepwise revised potential attenuation method. The comprehensive potential productivity was estimated by combined with social efficiency coefficient, with the resource utilization efficiency being evaluated. There were three main results. 1) Potential productivity of C. oleifera in Jiangxi varied from 10229 to 17724 kg·km-2, which decreased from the south to the northwest, with an average potential of 12550 kg·km-2. After classification, the area with higher and highest potential productivity reached 51656 km2, accounting for 31.1% of the total area. Among the cities, Ganzhou had the highest potential productivity. 2) The changes of potential productivity of C. oleifera ranged from 2223 to 3857 kg·km-2, with small regional difference for various levels. The resource satisfaction rate ranged from 69.3% to 122.7%, with small regional difference. The resource utilization efficiency varied from 49.1% to 85%. Regional utilization rate at all levels differed obviously. 3) The estimated comprehensive potential productivity was in line with the real production of C. oleifera in Jiangxi, and the assessed resource utilization efficiency was consistent with natural and social conditions. These results could be used as a reference for related research and policy making.To investigate soil fertility status and characteristics of typical tea plantations, we selec-ted 372 typical tea plantations of 21 areas across Jiangxi Province and analyzed the soil nutrient, spatial data, and their correlations with topography, soil type, elevation and plantation age. The results showed that soil pH, organic matter, alkaline nitrogen, available phosphorus, available potassium, total nitrogen, total phosphorus and total potassium of tea plantation in Jiangxi reached 53.9%, 60.1%, 56.1%, 22.9%, 38.5%, 43.7%, 11.1% and 95.5% of indices of high fertility, high efficiency and high yield tea plantation, respectively, with the available phosphorus showing a strong variation. Soil available copper, zinc, iron, manganese and boron reached 76.3%, 74.2%, 96.8%, 73.1% and 0.0% of the first-class standards for soil trace elements, respectively. Tea plantations with highest soil fertility located in central Jiangxi, followed by northeastern and northwestern Jiangxi, and lowest in southern Jiangxi. Soil and organic fertilizers to prevent soil acidification.Based on a long-term field experiment located in the central region of Mollisol in Northeast China, we examined the changes of soil fertility and nutrient supply capacity of the newly-formed soils with pot experiment after 14-year different agricultural management practices from parent material (PM) (down to 2.0-3.0 m depth) of a Mollisol, and finally tried to optimize pre-ferential agricultural practices improving soil fertility of seriously eroded PM. After 14-year different agricultural practices, soil organic carbon, total nitrogen, stability of soil aggregate and other rela-ted soil nutrient contents improved compared with PM. Soil fertility level of the newly-developed soils significantly affected nutrient supply capacity for wheat in the pot experiment. Results from principal component analysis showed that soil fertility developed toward to the surface Mollisol after 14 years of different agricultural practices from PM. Protein Tyrosine Kinase inhibitor Surface soils with higher organic carbon inputs in arable soil with chemical fertilizer plus all aboveground biomass incorporated and those in no-tilled alfalfa soil were much approached to surface Mollisol, followed by arable soil with fixed amount of organic inputs and natural fallow soil, while soils without and with only chemical fertilizer were much closed to PM. Our results indicated that 14-year organic carbon inputs improved soil aggregate structure and the decomposition of organic carbon entering into soil, changed soil physical and biochemical properties, and hence caused maturing of soil fertility of PM. Straw returning, organic manure application, and planting alfalfa were recommended for improving soil fertility of eroded soil. These findings would give a better scientific basis for high-efficient fertilization and management practices in eroded Mollisol region.