Spatial variability of soil nutrients in Juglans regia plantations in depressions between karst hills

Biomass and Carbon Sequestration by Juglans regia Plantations in the Karst Regions of Southwest China

“…Thus, these results may not be consistent with some reports of adult forests that have large amounts of root biomass in non-karst regions [29]. However, the large ratio of belowground (root) biomass to total biomass (0.27-0.50) of adult trees also highlights the importance of accounting for roots in the accurate estimation of the total biomass and carbon of plantation forests [21].…”

“…Although our previous study demonstrated relationships between biomass and soil nutrients in J. regia stands of different ages in depressions between karst hills [21], the uncertainty regarding C and biomass allocation of this species along different stand ages represents a major information gap that hampers efforts to estimate C pool dynamics in karst regions. Thus, the present study examined changes in biomass and carbon storage in four different J. regia plantations of different ages under the GGP in Fengshan County, Guangxi Province.…”

“…This county has a subtropical monsoon climate with an average annual temperature of 17.6 • C. The area receives an annual average of 2200 h of sunshine and 269 frost-free days, whereas the active accumulated temperature (≥10 • C) is 6426 • C. The mean precipitation is 1550 mm year −1 , with 65% falling during May to August. Evapotranspiration is approximately 1130 mm year −1 [21].…”

“…For these large plantations in SW China, it is necessary to understand the importance of J. regia stands in the regional C budget. Although there is abundant research on genome sequence, food chemistry, plant disease, and nutrient cycling in J. regia plantations [18,19,21], the biomass and carbon sequestration by J. regia plantations in the karst regions is still unknown. Therefore, a better understanding of C sequestration in J. regia plantations at a regional scale is fundamentally important for forest managers, policy makers, and researchers wishing to enhance forest C sequestration.…”

Crop biomass and root morphology in maize/soybean strip intercropping system in karst region

“…In detail, the mixture of soil and roots around maize centre were dug according to the distribution characteristics of root system in maize and soybean, and washed by using 60 mesh griddles. Then, the clean root were scanned by root scanning image analysis system (WinRHIZO) and the root length, root volume were calculated [16].The roots were oven-dried at 105°C for 30 min and then at 85°C until constant weights. Finally, the root actively was also measured by the method of TTC triphenyl four nitrogen chloride [17].…”