Close-to-nature forest management has been proposed as an effective method for improving the quality of plantation forests. Knowledge of spatial distribution patterns, structure, and succession trajectories in natural...Close-to-nature forest management has been proposed as an effective method for improving the quality of plantation forests. Knowledge of spatial distribution patterns, structure, and succession trajectories in natural forests can provide guidelines for the establishment of close-to-nature forest plantations. Such knowledge is lacking in natural spruce(Picea crassifolia) forests in the Qilian Mountains of China, impeding the establishment of production forests. We conducted a case study in the Qilian Mountains to analyze the relationships between the naturally-formed forest patches and terrain factors, spatial heterogeneity of stand characteristics, and stand structure following harvesting disturbance. Our results suggested that spruce plantations will be effective on the N, NE, and NW slopes, at elevations between 2700 and 3300 m, and on slopes ranging from 15° to 45°. Further, planted forest patches should occupy 64% of the slope area on semi-shady slopes(NE, NW). Spatial patterns in the studied forest exhibited a strong scale-effect, and an area of 0.25 ha could be used as the most efficient plot scale for the management of spruce plantations. Partial logging is an effective method for the conversion of spruce planted forests into nearnatural forests, and the intensity of partial logging can be determined from the negative exponential function relationship between stand density and DBH. Our results provided critical information for the development of spruce plantations and conversion of existing plantations.展开更多
This paper presents an empirical analysis of the effect that participation in an agricultural cooperative has on the transaction costs and net income of apple- growing farmers in Shandong province. Compared with indep...This paper presents an empirical analysis of the effect that participation in an agricultural cooperative has on the transaction costs and net income of apple- growing farmers in Shandong province. Compared with independent farming, agricultural cooperatives reduce transaction costs by 48 yuan/mu and increase farmers＇ net income by 321 yuan/mu. Other factors found to influence transaction costs and farmers＇net income were farmer＇s gender, educational attainment, farm size, the availability of market information, distance to market, and level of government support. Independent farmers＂ most common explanations for not participating in agricultural cooperatives were that doing so would not reduce transaction costs significantly and that the cooperatives would impede the autonomy of their decision-making.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.41522102,41701296,and 41601051)the CAS“Light of West China”Program
文摘Close-to-nature forest management has been proposed as an effective method for improving the quality of plantation forests. Knowledge of spatial distribution patterns, structure, and succession trajectories in natural forests can provide guidelines for the establishment of close-to-nature forest plantations. Such knowledge is lacking in natural spruce(Picea crassifolia) forests in the Qilian Mountains of China, impeding the establishment of production forests. We conducted a case study in the Qilian Mountains to analyze the relationships between the naturally-formed forest patches and terrain factors, spatial heterogeneity of stand characteristics, and stand structure following harvesting disturbance. Our results suggested that spruce plantations will be effective on the N, NE, and NW slopes, at elevations between 2700 and 3300 m, and on slopes ranging from 15° to 45°. Further, planted forest patches should occupy 64% of the slope area on semi-shady slopes(NE, NW). Spatial patterns in the studied forest exhibited a strong scale-effect, and an area of 0.25 ha could be used as the most efficient plot scale for the management of spruce plantations. Partial logging is an effective method for the conversion of spruce planted forests into nearnatural forests, and the intensity of partial logging can be determined from the negative exponential function relationship between stand density and DBH. Our results provided critical information for the development of spruce plantations and conversion of existing plantations.
文摘This paper presents an empirical analysis of the effect that participation in an agricultural cooperative has on the transaction costs and net income of apple- growing farmers in Shandong province. Compared with independent farming, agricultural cooperatives reduce transaction costs by 48 yuan/mu and increase farmers＇ net income by 321 yuan/mu. Other factors found to influence transaction costs and farmers＇net income were farmer＇s gender, educational attainment, farm size, the availability of market information, distance to market, and level of government support. Independent farmers＂ most common explanations for not participating in agricultural cooperatives were that doing so would not reduce transaction costs significantly and that the cooperatives would impede the autonomy of their decision-making.
