By establishing a long-term positioning experimental area in Yanyuan County and conducting soil sampling and analysis under different rotation patterns, this study investigated the dynamic effects of rotation patterns on soil physical and chemical properties. The results showed that compared with the traditional rotation pattern, the simplified rotation pattern significantly increased the contents of soil organic matter, total nitrogen, and available nitrogen, effectively improved the soil pH, and provided favorable soil fertility conditions for the continuous high yield of local forest-underground economic crops.

To investigate the effects of drought stress on the growth and fruit quality of apple trees, an 8-year-old Changfu No.2 Red Fuji apple tree in Yanhu District of Shanxi Province was selected as the experimental subject. Four water treatments including normal irrigation, mild drought, moderate drought, and severe drought were set up to explore the effects of drought stress on the growth and fruit quality of apple trees. The results showed that as the severity of drought stress increased, the germination rate, fruit setting rate, new shoot growth, and fruit size of apple trees significantly decreased; net photosynthetic rate, stomatal conductance, etc. also showed a significant downward trend; intercellular carbon dioxide concentration increased under moderate and severe drought stress, and water use efficiency increased slightly under mild drought but decreased with the aggravation of stress; drought stress significantly reduced the single fruit quality and unit area yield, while fruit quality indicators such as soluble solids, Vitamin C, and soluble sugar content increased under mild drought stress, but decreased significantly under moderate and severe drought.

To investigate the regulatory effect of Castanopsis hystrix and Pinus massoniana mixed planting on the diversity of understory plants, experiments with different mixed planting ratios and pure forest control were set up at the state-owned Liuwan Forest Farm in Guangxi Zhuang Autonomous Region. The results showed that the mixed planting treatment significantly enhanced the diversity of understory plants. Among them, the Shannon index of the shrub layer in the treatment with ζ (Castanopsis hystrix∶Pinus massoniana) = (3∶7)~(5∶5) was more than 62% higher than that of the pure Pinus massoniana forest, presenting a "single peak" change trend. The analysis of environmental driving mechanisms revealed that the mixed planting ratio indirectly promoted diversity enhancement by reducing canopy density, improving understory light conditions, and promoting soil nutrient accumulation (total effect 0.71). It was recommended to adopt the same-age inter-row mixed planting mode with ζ (Castanopsis hystrix∶Pinus massoniana)=(3∶7)~(5∶5) to achieve the coordinated improvement of forest growth and biodiversity.

This study focused on a 5-year-old artificial Pinus yunnanensis forest in Yanyuan County. Five gradients of humic acid fertilizers were set up. By measuring the growth indicators of the trees, biomass accumulation, and nutrient content, the regulatory effect of humic acid on the growth and development of Pinus yunnanensis was systematically analyzed. The results showed that an appropriate amount of humic acid significantly promoted the growth of Pinus yunnanensis. Among them, the 25 kg/667 m² treatment had the best effect, with a growth rate of 1.82 cm in diameter, an increase of 49.2% compared to the control group; a growth rate of 0.86 m in tree height, an increase of 53.6%; a growth rate of 42.35% in volume, an increase of 50.5%; and the biomass and nutrient content and reserves of roots, stems, and leaves, as well as nitrogen, phosphorus, and potassium nutrients, all significantly increased under this treatment, with the total biomass increasing by 51.6% compared to the control group.

Took the Yanyuan early-bearing walnut trees as the experimental subjects, an in-field experiment on foliar fertilizers was conducted in Yanyuan County. Six treatments were set up to explore the effects of foliar fertilizers on the yield and quality of Yanyuan. The results showed that compared with the control with clean water, spraying foliar fertilizers could significantly increase the yield per tree, the quality of individual fruits, and the kernel extraction rate of walnuts. Among them, the treatment of 0.5% urea+0.3% phosphoric acid potassium+800 times humic acid foliar fertilizer had the best effect, with a 28.38% increase in yield per tree and an 8.38% increase in kernel extraction rate. In terms of quality, the amino acid and humic acid foliar fertilizer compound treatment increased the protein content by 18.46%, the fat content by 14.65%, and the content of mineral elements also significantly increased.

Took the main cultivated Fuji apples in Yanyuan County as the research object, six different planting densities were set up to analyze the effects of planting density on the growth of apple trees, photosynthetic characteristics, and fruit quality. The results showed that as the tree spacing increased, the indicators such as tree height, trunk diameter, canopy size, and new shoot length all significantly improved. Low-density planting was beneficial for alleviating tree competition and promoting overall growth potential. The analysis of photosynthetic characteristics indicated that the 1.8 m tree spacing had the optimal photosynthetic rate, and the higher-density treatments increased by 20.7%, and stomatal conductance and transpiration rate were also significantly improved. In terms of fruit quality, the single fruit weight of T₄ treatment reached 195.42 g, and the soluble solids, sugar-acid ratio, and hardness of the higher-density treatments increased by 9.3%, 22.5%, and 6.3% respectively, with the best overall performance.

From 2023 to 2024, five growth regulators were applied in the field in Muli County for a field experiment to investigate the effects of different plant growth regulators on the growth and fruit quality of Red Fuji apples. The results showed that all the regulators could significantly promote tree growth. The comprehensive results indicated that benazin·glucosinolide had the best effect in increasing fruit size, sugar accumulation, and pectin content, while amino acid water-soluble fertilizer had a significant effect on the accumulation of solids and Vitamin C.

Rare native tree species are an important part of the national forest and have significant ecological, economic and social implications. This paper selected four rare native tree species as the research objects and discussed the techniques for creating artificial multi-layer mixed forests.

To investigate the effects of different pruning intensities on the growth and volume formation of Pinus tabuliformis plantations, five pruning intensity treatments were set up in Anlexi Township of Hezhang County in Guizhou Province. Tree height, stem diameter, canopy width, branch height below the ground, single tree volume, and stand volume were measured and analyzed. It was suggested to adopt a pruning intensity of 25% to 35% to optimize the growth and volume of Pinus tabuliformis, avoiding excessive pruning that leads to a decline in productivity, and providing technical references for the sustainable management of Pinus tabulifor-??mis forests in Karst mountain area.

Dairy buffalo farming plays a significant role in the economic development of animal husbandry in Nanning City. Ensuring the healthy development of the dairy buffalo farming industry is of great importance. This paper took Nanning as an example and focused on the management of dairy buffalo farming. It deeply studied the key points of scientific feeding and management techniques for dairy buffalo, including site selection and construction of dairy farms, selection and breeding of breeds, optimization of the herd structure, composition of feed types, processing and preparation of feed, staged feeding, environmental hygiene management, and biological safety management. The aim was to provide scientific technical guidance for dairy buffalo farming in Nanning and adjacent areas, and to promote the healthy development of dairy buffalo farming and the steady growth of the animal husbandry economy in Nanning.