Litterfall production and nutrient return in different-aged Chinese fir(Cunninghamia lanceolata) plantations in South China

The amounts of litter produced and nutrients returned play a fundamental role in the productivity and biogeochemical and nutrient cycling of forest ecosystems.We monitored annual litterfall production, nutrient return,and monthly dynamics over a one-year period in Chinese fir plantations aged 10, 22, and 34 years. Our objective was to quantify litterfall and nutrient return over a complete harvest rotation of Chinese fir. Annual litterfall production increased with stand age and was recorded as（3,294.6 ± 360.4）,（3,733.9 ± 211.2）, and（4,876.1 ± 212.8） kg ha-1a-1in stands aged 10, 22 and 34 years, respectively. Total litter production was significantly greater in the stand aged34 years than in the stand aged 10 years（p ／ 0.05）. With the exception of miscellaneous components, needle litterfall constituted the highest proportion（27.5–43.6 %）, followed by branches/twigs（9.5–16.6 %）. In all three plantations,annual total nutrient return to soil was in the order of C（1,119.95–2,709.05 kg ha-1a-1） [ N（39.32–62.04 kg ha-1a-1） [ K（15.95–22.44 kg ha-1a-1） [ P（1.30–1.63 kg ha-1a-1）. C, N, K and P input to soil was significantly lower in the 10-year-old stand in comparison to the 22- and34-year-old stands（p ／ 0.05）. Litterfall production and nutrient return（C, N and K） followed similar patterns, and C and N input to soil was significantly related to litterfall production（needle, branch and total litterfall）. C, N, P and K input to soil and total litterfall production were mainly driven by needle litterfall.

Optimal Pricing and Return-Freight Insurance:Strategic Analysis of E-Sellers in the Presence of Reputation Differentiation

Motivated by the practice that e-sellers cooperate with insurance companies to offer consumers the return-freight insurance(RI),this paper aims to investigate the competing e-sellers’RI strategies.Regarding the information asymmetry in the online context,reputation system is widely applied by e-platforms.In an online market with two competing e-sellers that sell the same product but are differentiated in their reputation,this paper builds an analytical model to explore the e-sellers optimal pricing and RI strategies.Combined with sellers’reputation and their RI strategies,the equilibrium outcomes under four cases are discussed.This paper reveals the conditions that e-sellers are willing to offer RI.Specifically,the findings demonstrate that low reputation e-seller is more likely to offer RI.Moreover,when the sellers are more divergent,they are more likely to co-exist in the market.Insurance premium and RI compensation play critical roles in their decisions.RI introduction tends to increase the price,thus offsets the benefits of RI,but does not affect the total consumer surplus.

Decision and Coordination of an E-commerce Supply Chain Considering Returns and Network Externalities

Considering the large number of returns in online sales and the network externalities of e-platforms,we develop a decentralized model and a centralized model to explore the impacts of returns and network externalities on e-commerce supply chain(ECSC)decisions.We show that in the decentralized model,the service level,price,market demand,and ECSC members’profits increase with the network externality strength.However,the service level and price increase,while the market demand and ECSC members’profits decrease with the product return rate.The centralized model is the optimal operating mode when it is properly coordinated.We design the“commission and return cost-sharing”contract to optimize ECSC,in which the proportion of the e-platform’s sharing of the return handling cost is exactly equal to the proportion of the system profit after coordination.Based on the decentralized model,we develop two extended models in which we endogenize the impacts of the service level and return rate on the network externality strength.Through comparisons between the extended and decentralized models,we show that high-quality service can improve ECSC’s profitability,while a high return rate hurts its economic performance.