粤北地区食用菌产业及其循环经济发展概述

从食用菌种类及其分布、产值、食用菌企业、食用菌产业循环经济发展情况等方面介绍了粤北地区食用菌产业发展现状,总结食用菌产业发展中存在的问题,如菌种问题突出,品牌意识缺乏;食用菌产业标准化落后;产品质量参差不齐,食品质量安全无保障;资源浪费严重;精深加工不足等,并提出相应的对策。     

Measuring trail users’ perception of crowding in a peri-urban nature park: A best-worst scaling experiment

This paper evaluates the perception of crowding, its determinants and relationship with trail users’ experience in a peri-urban nature park. Existing crowding surveys rely heavily on a single-item 9-point crowding scale which was originally developed for backcountry areas. Receiver operating characteristic (ROC) analysis was used to test the validity and reliability of this measure in detecting crowding issues and formulating visitor capacity limits. Low validity and reliability raised concerns about the applicability of this scale in similar frontcountry areas. Inability of this simple crowding measure to detect a visitor threshold brings to the fore its another important limitation – ignorance of the complexity of crowding phenomenon. The perception of crowding varies with various social, psychological and situational factors, and a best-worst scaling (BWS) experiment was designed to simultaneously evaluate different aspects of crowding in the Medvednica Nature Park, a peri-urban nature park near Zagreb, Croatia. The findings of BWS experiment revealed that occupancy of mountain huts, number of other hikers on the trail and amount of litter along the trail on average contributed most to the trail users’ sense of crowding. A latent class analysis identified a large heterogeneity in the perception of crowding; while one group of trail users (63%) was more disturbed by the direct social impacts, the others (37%) were more disturbed by the secondary impacts of other visitors, especially by the negative externalities from road traffic in the park. Older visitors had a greater tendency to primarily associate crowding with the environmental conditions. A higher impact of trail use level in the perception of crowding, younger age and more frequent use were associated with a more negative evaluation of crowding. The park management should closely monitor road traffic in the park and visitor activity on highly used trails, especially on those popular among younger trail users.     

Can trail spatial attributes predict trail use level in urban forest park? An examination integrating GPS data and space syntax theory

Understanding users’ spatial distribution in forest park is crucial for providing visitors with quality recreation experiences and for park planning and management. Utilizing users’ spatial distribution data, this study aims at investigating associations between trail use level and trail spatial attributes, through examining two large urban forest parks (Gongqing forest park and Paotaiwan forest park) in Shanghai, China. Users’ spatial distribution was measured utilizing GPS trackers with the interval of 10 seconds. This study conceptualizes trail spatial attributes as trail metric attributes and trail configurational attributes. Trail metric attributes include trail mean distance to gates, length, width and level of enclosure, which are calculated based on park map and on-site observation. We computed trail configurational attributes utilizing space syntax theory, which comprise measures of global integration, control, and connectivity. Trail connection with features/facilities, visual connection with water and shading are included as covariate variables. In total, we obtained 134 valid samples in Gongqing forest park and 210 valid samples in Paotaiwan forest park for analysis. Multivariate regression analyses indicate that when involving covariate variables, consistently in both parks, a greater trail usage is significantly related to trail shorter mean distance to park gate, trail width wider than 3 meters, higher global integration and higher control values. Collectively, these four trail spatial attributes explained 31.7 % (p < 0.001) and 27.3 % (p < 0.001) of the variances in trail use level in Gongqing forest park and Paotaiwan forest park. These findings provide direct implications to park designers and managers for providing visitors with different desirable social conditions, and ultimately improve users’ experiences and satisfactions.     

Soil protection for a sustainable future: options for a soil monitoring network for Ireland

The increased recognition of the importance of soil is reflected in the UN Post‐2015 Development Agenda with sustainable development goals that directly and indirectly relate to soil quality and protection. Despite a lack of legally binding legislation for soil protection, the European Commission remains committed to the objective of soil protection. However, the achievement of a legally binding framework for soil protection relies on the implementation of a soil monitoring network (SMN) that can detect changes to soil quality over time. As beneficiaries do not pay for the provision of soil information, the options for soil monitoring are limited. The use of existing data sets should be considered first. Using Ireland as an example, this research explored the opportunities for a SMN for Ireland considering three existing national data sets. The options for a SMN are considered in terms of their spatial and stratified distribution, the parameters to be measured and an economic analysis of the options proposed. This research finds that for Ireland, either a 10 or a 16 km² grid interval stratified by land use and drainage class offers the best potential in relation to the spatial distribution of existing data sets to reflect local data at a national level. With existing data, the stratified SIS data using the 16 km² grid offers the best value for money, with baseline costs for analysis, excluding field costs, of between €706 481 and €2.8 million. Acknowledging the impossibility of measuring all parameters with ideal frequency, this study proposes a two‐tier system for optimized monitoring frequency. Parameters must anticipate future policy requirements. Finally, the implementation of a SMN must be accompanied by standardized methods, defined thresholds and action mandates to maintain soil quality within allowable limits.     

社会林业与五指山的自然保护

五指山自然保护区是世界上现存地势最高的原始热带雨林之一，是我省目前面积最大的自然保护区，也是海南三大河流的发源地。但由于保护区横跨琼中、通什、保亭三县、市，紧邻保护区还生存着众多贫困的黎、苗族村民。因此，保护区与周边社区的联系是十分紧密的，社区的发展也直接影响到五指山热带天然林的保护。海南省林业局中德海南热带林保护和恢复项目在社会林业与五指山森林的保护上做出了有益的尝试，就在全省来说，也是首次对社会林业与森林保护上进行的探索。五指山地区社会林业的研究，对保护海南热带雨林也有着积极的意义。特对社会林业与五指山的森林保护进行了阐述、分析和设想。     

森林主产利用计划系统编制工作初探

森林经营方案的编制与实施是提高森林经营水平的重要步骤。在编案中森林主产利用计划系统的编制是关键的工作。本文针对森林主产利用系统在编制过程中存在的问题，提出解决问题的途径、方法及其前景。     

中文图书回溯建库中常见的书目数据质量问题及对策

本文对中文图书回溯建库过程中一些常见质量问题进行了举证说明 ,分析了产生错误的原因 ,并针对存在的问题提出了相应的对策 ,以确保书目数据的质量     

湟源县草地资源基本特点及开发利用

湟源县草地面积有 85 1 85 .1 3hm2 ,占全县土地总面积的 5 6.45 % ,草地资源丰富 ,牧草种类较多 ,农业生产秸秆来源广泛 ,但由于利用不当 ,造成了草地严重破坏和秸秆的浪费 ,如何合理利用草地和秸秆资源 ,扼制草地退化 ,是促进该县畜牧业发展的重要因素     

土地利用景观格局动态分析——以阜康荒漠绿洲为例

阜康荒漠绿洲土地利用景观格局受自然分异和水土资源开发利用程度的制约 ,通过划分景观样带和选取景观空间格局指标 ,本文重点揭示该区域景观格局的变化及其影响因子。结果表明 :( 1 ) 1 987年至 1 998年间阜康土地利用景观格局变化主要表现为耕地面积在洪积扇上增加 ,在冲积平原上下降 ;荒地则刚好相反。林地面积在低山丘陵带和洪积扇带下降 ,在冲积平原上没有变化。牧草地面积在低山丘陵带上升 ,其他各带均下降。城镇面积在各样带上都有所增加 ,水域各带基本不变。 ( 2 )低山丘陵带和洪积扇带景观多样性和均匀度下降 ,优势度上升 ;而冲积平原则多样性和均匀度上升 ,优势度下降。景观破碎度有增加的趋势 ,表明了人为影响的不断增强。