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101.
我国森林康养产业发展现状及路径探析——基于典型地区研究 总被引:3,自引:1,他引:2
森林康养作为“两山”理论的新实践,已成为我国绿色、健康产业的新业态、新模式,它的发展对建设“美丽中国”与“健康中国”具有重要战略意义。文中在阐述国内外森林康养相关概念及内涵基础上,结合我国典型森林康养地区的现状研究,对我国森林康养产业存在的问题进行探讨,并就其具体发展路径提出以下建议:1)提升理论认知,加强森林康养教育;2)完善政策指引,实现产业合理布局;3)优化资源利用,构建产业等级制度;4)完善后勤服务,强化人才队伍建设;5)强化创新意识,丰富森林康养内涵;6)结合地区特色,打造品牌产业。 相似文献
102.
不同有机物投入对新垦耕地红壤肥力及蔬菜生长的影响 总被引:2,自引:0,他引:2
[目的]比较不同有机物对新垦山地土壤的培肥效果,为开展新垦耕地后续培肥管护提供科学依据。[方法]在新垦山地红壤地,以3种不同有机物投入为因素,以空白为对照,在一年三熟蔬菜种植模式下,经连续3年小区试验,比较其对新垦耕地红壤肥力及蔬菜生长的影响。[结果]在3种有机物中,商品有机肥无论是在土壤培肥方面还是在蔬菜作物生产方面,均能体现出最佳效果。[结论]商品有机肥可作为新垦红壤地区施用的外源有机物之一予以推荐。而食用菌废渣的效果次之,可作为替代物品,水稻秸秆效果较差。 相似文献
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104.
浙江省低丘缓坡区有土地资源3万8235km^2,对浙江省经济建设与社会发展具有重要意义。阐述浙江省低丘缓坡区土地资源开发利用的主要领域及发展趋势,分析低丘缓坡土地资源开发利用中水土保持存在的主要问题,提出水土流失综合治理的对策。 相似文献
105.
Lou Frotté Julien Ringelstein Dominique Monti Marie Robert Christophe Pécheyran Nadia Améziane Hélène Tabouret 《Ecology of Freshwater Fish》2020,29(1):132-144
All native fishes living in the Caribbean island rivers are considered diadromous but few species have been validated as diadromous. In Guadeloupe (Lesser Antilles) as well as in the other tropical islands, the riverine habitats are subject to strong anthropogenic pressure due to resource modifications or dams. The management of fish biodiversity requires knowledge concerning their life history traits and behaviour that are still unknown for most species at a local scale and at the whole distribution area of the species. In a Guadeloupe river, we inferred the migratory patterns of four freshwater fishes common to Caribbean rivers by the analysis of otolith microchemistry. We found two species Eleotris perniger (Eleotridae) and Sicydium plumieri (Gobiidae) to be completely amphidromous with a marine larval phase and a freshwater adult phase. Agonostomus monticola (Mugilidae) was also found to be amphidromous in this system. The fourth species Gobiesox cephalus (Gobiesocidae) showed elemental ratios suggesting an estuarine larval phase and was defined as “limited amphidromous”. The identification of such life history traits, with limited dispersion abilities, argues for specific management measures in tropical island rivers at a basin scale for the conservation of biodiversity. 相似文献
106.
Zewei Sun Daowei Zhou Luis M.M. Ferreira Qingzhen Zhong Yujie Lou 《Livestock Science》2008,116(1-3):146-155
The botanical composition, intake and digestibility of the diet selected by Inner Mongolian Cashmere goats grazing on a native Leymus chinensis plant community were measured in two grazing periods (June and August) using the n-alkane markers. In each grazing period, 48 Inner Mongolian Cashmere goats (24 wethers and 24 does with an average live weight of 22.1 ± 1.2 kg and 19.6 ± 0.8 kg, respectively) were divided in two groups (G1: grazing group; G2: cage-fed group) of 24 animals each. Based on the observation of G1 grazing behaviour, G2 goats were fed on herbage obtained by a simulative method and were housed in metabolism cages to determine the alkane faecal recoveries. Diet composition was estimated by comparing the odd-chain n-alkane pattern (C25–C35) of the selected plant species with the n-alkane faecal concentrations, corrected for their incomplete faecal recovery. The alkane pair C32:C33 and C36 alkane were used to estimate intake and diet digestibility, respectively. The results showed that the increase of herbage availability from June to August, resulted in higher (P < 0.05) DM, CP, ME, ADF and NDF intake of both wethers and does, with no evident changes in ADF and NDF intake in does., The intake of nutrients differed significantly between wethers and does in both experimental periods, except for NDF in EP1 and ME in EP2. Differences between grazing seasons and goats' sex in nutrients digestibility were not observed. Diet composition indicated seasonal differences, being Sonchus brachyotus, Artemisia frigida and Phragmites communis the main components of the diet in June. However, Suaeda corniculata, Chloris virgata, Xanthium sibiricum and Echinochloa crusgalli became the main diet components in August. Moreover, the sex affected significantly the diet choices in both grazing periods. 相似文献
108.
Yu Li Jie Wang Yongsheng Cao Weidong Gao Jiahe Fang Xizhi Lou 《Genetic Resources and Crop Evolution》1998,45(2):181-186
The use of crop genetic resources in improvement programmes should be the ultimate objective of all undertakings in the field of germplasm resources. The present situation and future direction of the use of crop germplasm in China was assessed from responses to a questionnaire distributed to 165 plant breeders and curators nationwide. The general opinions for the limiting factors of germplasm utilization were also evaluated. Responses from the questionnaire indicated that the use of germplasm in breeding programmes is much more important than the direct use of germplasm in crop production as cultivars released. Among different types of crop genetic resources, released varieties and breeding lines contribute more to crop breeding. Wild relatives and genetic stocks, however, are expected to play a greater role in the future. Landraces will remain important in improvement. Limited useful germplasm available to breeders is the basic reason for the insufficient use of germplasm in crop breeding at present. The complex reasons which affect the availability of useful germplasm involve the research level, links between breeder and curator and others. To counter these, we propose some suggestions and measures which can be implemented in the near future. 相似文献
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