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Sacred groves are patches of forests preserved for their spiritual and religious significance.The practice gained relevance with the spread of agriculture that caused large-scale deforestation affecting biodiversity and watersheds.Sacred groves may lose their prominence nowadays,but are still relevant in Indian rural landscapes inhabited by traditional communities.The recent rise of interest in this tradition encouraged scientific study that despite its pan-Indian distribution,focused on India’s northeast,Western Ghats and east coast either for their global/regional importance or unique ecosystems.Most studies focused on flora,mainly angiosperms,and the faunal studies concentrated on vertebrates while lower life forms were grossly neglected.Studies on ecosystem functioning are few although observations are available.Most studies attributed watershed protection values to sacred groves but hardly highlighted hydrological process or water yield in comparison with other land use types.The grove studies require diversification from a stereotyped path and must move towards creating credible scientific foundations for conservation.Documentation should continue in unexplored areas but more work is needed on basic ecological functions and ecosystem dynamics to strengthen planning for scientifically sound sacred grove management. 相似文献
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《African Zoology》2013,48(2):172-179
A qualitative survey of the leaf-litter earthworm fauna of 11 selected indigenous forests in Limpopo Province, South Africa, was conducted to identify the species present, to describe the communities and to assess the relationship between indigenous and exotic species. A total of 8185 individuals from 17 species (five indigenous and 12 exotic species) were recorded. The average earthworm community comprised fewer than five species, but up to seven species were sampled from a single forest. Four of the species recorded are national (one species), regional (one species) or local (two species) endemics. Because these species are not known to live elsewhere, the protection of Limpopo Province forests is critical to their survival. The majority (71%) of the earthworm species sampled was exotic, and differences between exotic and indigenous species richness in forests were mostly significant. At the two spatial scales examined (20 m2 and individual forest) there is no evidence of an association between exotic and indigenous species richness. However, we cannot assume that exotic earthworms do not impact the forest ecosystem. 相似文献
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晋中晚熟冬小麦“窄行稀条播”的群体质量和产量效应 总被引:1,自引:0,他引:1
针对晋中晚熟冬小麦群体质量不高、水肥利用率低等问题,以大穗型品种山农9-1和多穗型品种山农9801为材料,在不改变播量和水肥投入的情况下,探讨了窄行稀条播种植模式(行距10 cm)对冬小麦群体和产量的影响。结果表明,与常规条播种植(行距20 cm)相比,窄行稀条播极显著提高了小麦产量,其中山农9801增产幅度大于山农9-1;山农9-1增产原因是穗粒数、千粒重、成穗数都显著提高,而山农9801是成穗数和穗粒数分别极显著和显著提高。窄行稀条播增加了各个生育阶段的群体数量,提高了分蘖成穗率和叶面积系数,而且延长了叶片功能期。说明窄行稀条播种植模能改善晋中晚熟冬小麦群体数量和质量,进而起到增产作用。 相似文献
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为解决木材细胞纤维图像分割中的某些图像分割不连续的现象,引入了基于形变模型(DeformableModels)的水平集(LevelSet)方法对木材细胞图像进行分割,并用Matlab实现了基于该形变模型的窄带(NarrowBand)快速算法。对针叶材和阔叶材的显微图片进行仿真试验表明,该方法适合于对具有分支、突触以及拓扑结构变化的木材细胞图像进行快速精确分割,不但具有全局优化的能力,而且可以检测出模糊或离散状边界,对噪声也有一定的鲁棒性。 相似文献
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Andrea Coppi 《Biological conservation》2008,141(8):2000-2011
Although several plants endemic to Corsica and Sardinia are included in various redlists, no attempts have been made to analyse their genetic diversity with molecular techniques. Genus Anchusa occurs with seven taxa in either mountain or coastal habitats of the two islands, but the very restricted range and low population size pose these endemisms in a very precarious conservation status. Highly variable markers (AFLP) were therefore used to analyse the patterns and levels of genetic diversity in a sample of 11 populations from the entire range of the group.Results indicate the separation between a mountain genic pool including Anchusa formosa, Anchusa capellii and Anchusa montelinasana, and four groups of coastal accessions. In spite of small size, mountain taxa show low interpopulation differentiation (Fst = 0.02) and relatively high intrapopulation genetic variation (0.365), while coastal accessions showed on average a stronger differentiation (mean Fst = 0.20) and a lower diversity (0.281), possibly due to higher rates of inbreeding. The particularly low levels of variation found in A. sardoa, A. littorea and A. crispa ssp. maritima from the Coghinas bay are likely due to a historical decrease of populations and to bottleneck events caused by loss of habitat and natural stochastic factors on sand dune ecosystems. While habitat maintenance and regulation of grazing by domestic herbivores should be sufficient to ensure the persistence of the mountain endemics, additional actions of in situ and ex situ conservation are needed for the critically endangered coastal species A. sardoa and A. littorea. A. crispa showed a relatively high variation, especially on Corsica. No correlation between population size and genetic variation was found in the latter species, highlighting the importance of the small patches for its conservation. Also, the genetic separation between subspecies crispa and maritima stresses the need of keeping them distinct in redlists and conservation actions on Sardinia. 相似文献
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半矮秆大豆窄行密植超高产栽培产量性状及产量结构研究 总被引:1,自引:0,他引:1
采用3个基因型品种,2种栽培模式,设置3个处理,研究半矮秆大豆窄行密植超高产栽培技术产量性状及产量结构,旨在为超高产大豆研究与应用提供技术依据.结果表明:在窄行、密植、高肥水条件下,B45处理由于采用半矮秆品种植株矮、底荚低、秆强不倒,虽然单株荚数、粒数显著低于对照,但由于密度增加,群体荚数、粒数显著增加.每节位平方米荚数、粒数分别达到145.1个和411.7个,分别较对照增加78.8~84.0个和254.2~258.0个,顶荚部位荚、粒数分别占总数的21.3%和22.5%.产量极显著高于对照处理,2008年在760 m2面积上,大豆产量达到4 895.7 kg·hm-2. 相似文献
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根据大豆窄行密植栽培技术的特点及实现提高大豆单产、增加总产的要求,进行试验并提出了技术措施,供有关人员参考。 相似文献