论土地资源管理专业的特色建设与发展

以师范院校工科土地资源管理专业建设为基础，针对大测绘的学科基础，提出具有特色的土地资源管理专业建设思路，并在人才培养目标的确定、课程培养体系的设置、实践教学改革与实践基地的建设、师资队伍建设、教育与教学研究等方面给出特色专业建设的基本途径与方法。     

陡坡地采伐归堆机的研究设计

针对我国北方林区采伐机械的作业特点，研制出一种适合复杂林地条件下的陡坡地小径木采伐归堆机。该机装有带车轮、可液压调整的一对后支腿和带有底板的一对前稳定支腿，其可在陡坡山地和沼泽地环境下作业，尤其适用于陡坡山地的采伐集材作业，是一种比较理想的作业设备。     

论搞活山地流转机制是林业发展之路

搞活山地流转机制，推行林业适度规模经营，是由当前社会大环境和林业自身的特点所决定的。本文在论述搞活山地使用权流转机制时调动林农积极性、发展林业和振兴经济的作用的同时，进一步分析了山地使用权流转的各种形式，并指出评价山地使用权流转形式好坏的标准，是坚持“三个有利于”的标准。     

特旱年旱地玉米限额补灌水肥效应分析

采用田间试验方法研究了旱地玉米限额补灌的水肥效应。结果表明，玉米小喇叭口期灌水675mm／hm2，平均增产玉米2171.5kg／hm2，增产率89．27％，灌水生产效率为3.217kg／mm;3种肥料的增产效果为N＞M＞P。未灌水条件下，3种肥料的增产效果为M＞P＞N。配合施用的增产效果为NPM＞NP。     

Towards flexible management of postharvest variation in fruit firmness of three apple cultivars

Stochastic modeling provides a useful tool in managing biological variation in the postharvest chain. In the current study, the fruit-to-fruit variability in the postharvest firmness of apples was modeled. Apples from three cultivars (‘Jonagold’, ‘Braeburn’, and ‘Kanzi’) were harvested at different levels of maturity, and stored at different temperatures and controlled atmosphere (CA) conditions. By using a kinetic model describing firmness breakdown as a function of time, temperature, controlled atmosphere conditions and endogenous ethylene concentration, the main stochastic variables were identified as the initial firmness and the rate constants for firmness breakdown and ethylene production. Treating these variables as random model parameters, the Monte Carlo method was used to simulate the propagation of the fruit-to-fruit variability in flesh firmness within a batch of apples during storage under different CA conditions and subsequent shelf-life exposure. The model was validated using independent data sets from apples picked in a different season. The model developed in this study can be used to predict the probability of having apples of certain firmness after long term storage for different scenarios of temperatures and CA conditions.     

Sustainable Mountain Watershed Management in China

在分析中国水土资源的状况及水土流失危害的基础上，作者介绍了中国山区流域经营的主要经验与措施体系；应用全国各大流域２０个典型，分析了流域经营的效益．为了判别流域经营的可持续性，提出了包括社会经济与生态环境两个方面的可持续流域经营指标体系．     

The Impacts of Irrational Exploitation and Utilization of Water Resources on Land Desertification and Its Countermeasures in the Arid Area of China

水是干旱区最为宝贵的自然资源之一，水量平衡在很大程度上影响着土地荒漠化过程．本文在荒漠化公约所作的荒漠化气候分区的基础上，对干旱区因水资源的不合理利用对土地荒漠化的影响如土壤盐渍化、植被退化和现有耕地的废弃加以综合分析，并据此提出了缓解这些影响的相应对策．     

21世纪我国农业资源配置战略

水土问题是２１世纪可持续发展诸多矛盾的焦点。进入８０年代水土对我国农业的约束不断硬化，并长期困绕我国农业的可持续发展，摆脱困境的基本思路是实施农业资源高效持续配置战略－－“实现四个结合，建设六大体系”。     

Preharvest and postharvest factors related to off-odours of fresh-cut iceberg lettuce

The influence of different preharvest and postharvest factors affecting off-odour development of fresh-cut iceberg lettuce in low-O₂ modified atmospheres (MA) was investigated. Fresh-cut iceberg lettuce developed undesirable off-odours under low O₂ and elevated CO₂ atmospheres. A strong relationship between CO₂ concentration and off-odour development was observed. Significant differences in off-odour development existed among different cultivars in two harvests in consecutive years. The influence of maturity stage was evaluated, comparing fresh-cut product from immature and over-mature heads with commercial ones. Higher CO₂ concentrations and higher accumulation of ethanol and acetaldehyde were detected in the headspace of MA-packed lettuce from immature heads. Differences in respiration rate of the fresh-cut product from heads cultivated during the winter–spring seasons were around 30%. Respiration rate of fresh-cut iceberg lettuce increased when medium temperature during cultivation increased. Changes in the product weight generated different CO₂ levels which correlated with the production of ethanol and acetaldehyde and other off-odour metabolites related with the lipoxygenase (LOX) pathway such as hexanal, 1-hexanol, and cis-3-hexen-1-ol. Volatile compounds such as cis-3-hexen-1-ol, β-elemene, ethyl acetate and dimethyl sulphide increased their content more than 10 times compared with other volatiles. Moreover, differences in the initial flushed gas-mixture with or without CO₂ showed higher CO₂ concentrations and the development of stronger off-odours when samples were flushed with an enriched CO₂ gas-mixture. In summary, visual quality of fresh-cut iceberg lettuce is important but so are odour and flavour. MAP currently used for fresh-cut lettuce may need some modification to inhibit off-odours and achieve better aroma and flavour qualities for preserving “freshness” of the cut product. Screening for cultivars with low browning potential and fermentation, harvested at optimum maturity stage and with an adequate package design are recommended.     

应用灰色系统理论评价草地质量初探

以草地优良牧草产量、可食牧草产量、载畜量、牧草利用率和覆盖度为主要指标，应用灰色系统理论中关联工分析的方法，对武威地区３２个类型草地质量进行了评价。结果表明，质量最好的草地是山地草甸，质量最关的是干荒漠和荒漠摹。根据分析结果，提出了武威地区草地质量分级的方案。