Responses of Chilean forest birds to anthropogenic habitat fragmentation across spatial scales

Although it is recognized that anthropogenic forest fragmentation affects habitat use by organisms across multiple spatial scales, there is uncertainty about these effects. We used a hierarchical sampling design spanning three spatial scales of habitat variability (landscape > patch > within-patch) and generalized mixed-effect models to assess the scale-dependent responses of bird species to fragmentation in temperate forests of southern Chile. The abundances of nine of 20 bird species were affected by interactions across spatial scales. These interactions resulted in a limited effect of within-patch habitat structure on the abundance of birds in landscapes with low forest cover, suggesting that suitable local habitats, such as sites with dense understory cover or large trees, are underutilized or remain unused in highly fragmented landscapes. Habitat specialists and cavity-nesters, such as tree-trunk foragers and tapaculos, were most likely to exhibit interactions across spatial scales. Because providing additional sites with dense understory vegetation or large habitat trees does not compensate the negative effect of the loss of forest area on bird species, conservation strategies should ensure the retention of native forest patches in the mixed-use landscapes.     

Effects of deficit irrigation strategies on cluster microclimate for improving fruit composition of Moscatel field-grown grapevines

The grapevine plays a very important role in the economic, social and cultural sectors of many regions; however vineyards are often grown in regions under stressful conditions and thus they are vulnerable to climate change. The objective of this research was to investigate the effect of partial root-zone drying (PRD) irrigation on vine water relations, vegetative growth, plant microclimate, berry composition and yield components, compared to conventional deficit irrigation (DI, 50% ETc), full irrigation (FI, 100% of ETc) and non-irrigated vines (NI). The study was undertaken in mature ‘Moscatel’ grapevines (Vitis vinifera L.) grown in Pegões, South of Portugal. Compared to the other irrigated treatments, PRD vines showed a better microclimate at the cluster zone with higher incident photosynthetic photon flux density (PPFD). Within the more open canopies of NI and PRD treatments, berry temperatures were higher than those of denser ones (DI and FI). Compared to the conventional irrigation technique the better microclimate observed in PRD vines was a consequence of a reduction in vine growth, where lower values of leaf layer number, leaf area, canopy wideness, water shoots and shoot weight were observed. In PRD vines we observed a tendency to a development of a deeper root system, while DI and FI showed a more homogeneous root distribution throughout the different soil layers. PRD showed an improvement in berry quality with higher values of flavour precursors, and total phenols concentration without any significant yield reduction compared to DI and FI.     

Analysis of flowering,stigmas yield and qualitative traits of saffron (Crocus sativus L.) as affected by environmental conditions

Saffron is well known for its use as a condiment spice, as a dye and traditional medicine. Saffron is experiencing an increasing interest mainly due to its peculiar and manifold properties of the metabolic pool of its stigmas, mainly crocetin esters and picrocrocin. This species is cultivated in environments with very different climatic conditions and with very different corm rates from place to place, passed down over the centuries. The aim of this study was therefore the evaluation of the influence of rainfall, temperature and corm density on flower phenology, stigmas yield and main compositional characteristics of two saffron corms provenience. Flowering beginning in saffron seems to be influenced by the combination of temperature and soil moisture, whilst its flowering calendar proves independent of corm provenance, environment and plant density. On the contrary, the studied factors exert a strong effect on both total stigmas yield and qualitative characteristics: colder environment resulted in a higher flower production, but lower quality of stigmas. Flower number was positively correlated with the stigmas yield, but negatively with its unitary weight. The content of crocetin esters and picrocrocin has been evaluated according to the spectrophotometric ISO normative, which ranked the samples into three qualitative decreasing categories (I–III). The spectrophotometric data showed positive correlation with the unitary stigmas weight and negative with stigmas production.     

有效积温对中华常春藤生长的影响

通过调查中华常春藤的生境和测量茎的生长情况,总结了中华常春藤的种植特点和分枝方式,同时利用SPSS软件的回归分析建立回归模型,并根据建立的模型用Excel软件绘制坐标图。结果表明:中华常春藤主枝生长完毕所需的有效积温为2 718.34℃/d;茎伸长量随有效积温延续的变化呈"S"形曲线,而茎伸长速度变化趋于钟罩型单峰曲线。再利用此结果估算出:在理想的生长条件下采用三角形定植方式定植中华常春藤为宜,并且植株与植株之间的最佳定植密度为510 mm×510 mm。     

土壤容重对生姜生长及产量和品质的影响

以莱芜大姜为试材,研究了容重分别为1.49(CK)、1.36(T1)、1.20(T2)g·cm-3的3种土壤对生姜生长及产量、品质的影响。结果表明,容重较小的土壤,其孔隙度较大,最大持水量较高,有利于生姜植株的生长和产量的提高。生长末期T2的株高、茎粗、分枝数和叶片数分别比CK增加17.9%、14.0%、35.2%和36.1%,单株根、茎、叶、根茎鲜质量分别比CK提高43.3%、24.4%、28.1%和35.2%,收获时CK、T1、T2的产量分别为2534.1、3017.7和3326.8kg·(667m2)-1,处理间差异极显著。此外,生姜根茎干物质、淀粉及挥发油含量随土壤容重降低而降低,而蛋白质、游离氨基酸则相反,粗纤维、可溶性糖及VC含量则基本不受土壤容重的影响。     

不同落叶提取液对豇豆种子化感效应的研究

以豇豆种子为受体材料,研究5种落叶提取液对豇豆种子的化感作用.结果表明:不同浓度的落叶提取液对豇豆种子发芽和幼苗的生长有不同的影响,落叶提取液对种子萌发表现出高浓度抑制、低浓度促进的现象.对幼苗的生长有一定的促进作用,小叶榕、黄桷兰落叶提取液不同程度地抑制豇豆的干物质重,且随着浓度的增加,抑制作用逐渐增强;桂花落叶提取液对豇干物质重的影响呈现出低浓度促进、高浓度抑制现象.     

十个芍药品种气孔特性研究

选取10个品种的芍药作为研究对象,观察芍药叶片气孔的形态、分布规律,并对其气孔大小、气孔长宽比、表皮细胞密度、气孔密度及气孔指数等进行品种间比较及差异分析.结果表明:10个品种的芍药叶片气孔形态及分布规律一致.各项指标的品种内变异系数均较小.4个品种(1、2、8、9)的4项指标(气孔长度、宽度、长宽比及气孔指数)均没有差异.2个品种(1、9)的5项指标(气孔长度、宽度、长宽比、气孔密度及气孔指数)均没有差异.各项指标相比较,气孔宽度和气孔指数在各品种间变化较小.气孔密度与气孔长度呈反相关.结果不支持将气孔长度、宽度、气孔长宽比、气孔密度、气孔指数及表皮细胞密度作为芍药种或品种分类的依据.     

A Study on Seedlings'''' Density of Aralia elata

lntr0duction,4ruliaehIIa(Miq)see111isaIcaflosingSI11aIltree\\I1icl1beI0ngst0AraIiaceaeCl1inesAraIia.Itisoncki11doflnedicala11dcatablepla11ts.Tl1e.tcl1desl1ootil1earIysprillgisvaIuabIewiIdvegeIabIes-\vI1icl1c0l1lail1sricl1protei11,fat,restoredsugar-orgal1icacida11d111tICI1vi-tamin.Itis0neofInail1\viIdvcgetabIestbrexP()rt.However,thiswitdresoLlrceisco111i11gtobeexI1aIIsctcdbecaLlseofI1eaveygatI1eri11gforyears.Seedil1gal1dgrowillgseedlil1gexperi111cl1tof,,11-'Ili`IehII'Itvascotl11…     

不同栽培措施对温室油桃含糖量的影响试验研究

通过增施钾肥、铺反光膜、限制产量的栽培措施试验，结果表明：不同K肥水平对油桃含糖量影响有显著差异，株施60g钾肥油桃含糖量最高为13．6％；行间铺设反光膜与未铺反光膜对油桃含糖量影响有显著差异，行间铺设反光膜比未铺反光膜油桃含糖量高1．8％；不同产量水平对油桃含糖量影响有显著差异，产量控制在12000kg／hm2时油桃含糖量最高。     

8203号杨木材基本性质的测定

本文对８２０３号和木材基本性质进行了测定，其结果：基本密度０．３４５ｇ／ｃｍ＾２；气干密度０．４０ｇ／ｃｍ＾２；干缩系数０．３６；纤维长度１３３７μｍ，长宽比５１；综纤维素含量８０％。８２０３号杨适宜制作各种板材及建筑用材，同时也是较理想的制浆、造纸材种。