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1.
Cultural ecosystem services related to urban green spaces contribute significantly to liveable cities. While previous studies highlight the intersection of cultural ecosystem services with societal values, spiritual or religious values associated with urban nature have received less attention. In India, as in other parts of the world, sacred sites are known for their biological richness, but analyses from urban sacred sites are largely missing. Based on a stratified random sampling approach, we analysed the cultivated and wild plant species assemblages of 69 sacred sites in the megacity of Bengaluru, India, in relation to biological and cultural features, and parameters related to the urban matrix and type of sacred sites (temple vs. katte). Unlike other urban studies, we found a dominance of native species in the cultivated and spontaneous species pools (121 species in total), with Ficus religiosa and Azadirachta indica as most frequently planted species. Culturally relevant species prevailed in the species pool (89%), with overlaps between religious (36%), medicinal (50%) and ornamental (62%) plants; only 11% of species were weeds. Urban matrix parameters (age of development, housing density) and size and type of sacred sites were related to differences in species assemblages. We identified key species for different classes of age and housing density, and for types of sacred sites. Our study demonstrates that urban sacred sites have an important potential in harbouring both native and culturally significant species that can support urban livelihoods in developing countries by a range of cultural and provisioning ecosystem services, including medicinal uses. As such sites are conserved by communities for spiritual or cultural beliefs, local biodiversity can be enhanced, e.g. by adapting management practices through community participation. This would strengthen the important contribution of sacred sites within the green infrastructure of rapidly growing megacities.  相似文献   
2.
伴随多元化时代的来临,用户的知识需求日益多元化、专业化,对图书馆服务提出了新的挑战。对智慧图书馆微观知识生态系统运行机理的研究,能够为新型知识服务提供理论基础,保障知识资源进行有效的优化整合,实现服务升级。文章在简要分析智慧图书馆微观知识生态系统四大要素的基础上,着重从社会发展、技术进步,知识富集、优化调整和需求驱动、服务升级三方面探讨其形成动因,重点分析智慧图书馆微观知识生态系统的生命周期,最后从合作、循环和保障三方面探讨其运行机理。  相似文献   
3.
Integrated crop–livestock–forest is a promising strategy to improve soil quality. It comprises four different integrated farming systems: crop–livestock, crop–forest, forest–livestock and crop–livestock–forest. This work systematically reviewed studies about integrated crop–livestock–forest systems and soil quality. A total of 92 papers were retrieved from the Web of Science—Clarivate Analytics platform, and the following information was analysed: publication year, institution, region of the studied site, type of integrated system, soil type, tillage system, maximum soil depth and the soil quality indicators assessed. Most studies were published in the second half of the 2010s. Brazil is a prominent focus of research about soil quality and integrated crop–livestock–forest systems, with significant contribution from its central and southern regions. The Embrapa was the main publishing institution, present in over one‐third of the studies. Crop–livestock was the most common integrated system, Ferralsols was the most common soil group, and most of the studied soils were clayey. No tillage was the main tillage system. Most studies focused on the topsoil, assessing physical and/or chemical soil quality indicators. More emphasis on biological indicators of soil quality is required, as well as assessments integrating biological, physical and chemical indicators of soil quality. Future works should compare different integrated systems, including assessments deeper in the soil profile, especially in systems with the forest component, and also in sandy and silty soils. Soil quality indicators that have been rarely used should be further tested. Novel indicators should be added to better understand the promotion of soil quality by integrated crop–livestock–forest systems.  相似文献   
4.
Pike (Esox lucius) occupy coastal streams and rivers of the Baltic Sea, where they attain large sizes (>5 kg). These large sizes are perhaps due to the fact that they can tolerate relatively high salinities and can thus forage in the nearby more productive brackish environments. In an attempt to quantify the extent to which pike utilise brackish environments, and to provide some insight into the underlying causes for brackish water migrations, we tagged 30 pike from a western Baltic river with acoustic transmitters and were able to track 21 individuals for 1 year. Based on experienced from local anglers, this population was assumed to be brackish in nature, where individuals underwent freshwater migrations to spawn. Our findings however suggest that the smallest and most active individuals make short exits into brackish waters and do so on rare occasions. Our results further indicate that neither sex nor size is related to activity level. We suggest that these patterns reflect two distinct behaviours—active and passive—and that large pike can be supported by the food availability in the river, without the need to venture into coastal zones, thus defying the conventional view that Baltic pike are all brackish in nature.  相似文献   
5.
本试验测定了pH、温度和EDTA对纯化的绵羊的瘤胃微生物胞外蛋白酶活性的影响,并用一已知氨基酸排列顺序的肽段(由15个氨基酸组成)作为底物,进一步测定了蛋白酶的酶切位点。结果表明,(1)纯化蛋白酶的最适pH在6.0~6.5之间,最适温度为40℃左右。(2)不同浓度的EDTA(浓度分别为1,10,25,50,75和100mM)对蛋白酶活性没有影响,因而该酶属于丝氨酸蛋白酶类。(3)纯化蛋白酶是一种内肽酶,其酶切位点在组氨酸—酪氨酸(?)、天冬氨酸—丙氨酸(?)、亮氨酸—赖氨酸(?)和(或)缬氨酸—赖氨酸(?)相连的肽键。(4)胰蛋白酶和纯化的蛋白酶虽同属丝氨酸蛋白酶类,但前者对底物具有高度的专一性,后者对底物的专一性不强,这是瘤胃内饲料蛋白质强烈降解的主要原因之  相似文献   
6.
西藏山南地区草地资源及其合理利用   总被引:5,自引:2,他引:3  
由于对西藏山南地区草原状况缺乏全面认识,未能合理利用,出现了草原退化等一系列问题。为了合理开发利用草地资源,通过调查提出:调整畜群结构,推行草场有偿承包责任制,开展季节性畜牧业,建立草地农业生态系统等建议。  相似文献   
7.
降低反刍动物甲烷排放的研究进展   总被引:7,自引:0,他引:7  
本文阐述了反刍动物瘤胃甲烷生成的生物学机制及影响反刍动物瘤胃甲烷生成的因素,并用产明了降低瘤胃甲烷产生的方法,最后对降低甲烷生成的前景作了展望。  相似文献   
8.
阐述了体外产气法的原理、影响体外产气量的因素及其研究前景。  相似文献   
9.
Established by the former Ministry of Forestry in 1986, Dagangshan Forest Ecosystem Research Station is one of the 14 national key sites in the field of ecosystem research. In this paper, the basic situation of Dagangshan Forest Ecosystem Station is described, including geographic location, natural conditions, biological resources, research conditions, instruments, achievement, prospects etc.  相似文献   
10.
上黄村草地生态系统能流和物流的初步研究   总被引:2,自引:0,他引:2  
上黄村草地土壤生态系统能量投入主要是动力投入,无营养物质投入。人工草地能量产出占总能量产出的50%以上,而面积仅占总面积的20%~52%;草地能量投入具有起伏性,产出具有波动性。草地土壤生态系统营养物质移出是草地土壤肥力退化的根本原因,无营养物质投入的人工草地更加剧了营养物质的迁出及土壤肥力的退化。  相似文献   
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