生姜群体及其光合作用与产量形成关系的研究

研究结果表明，姜群体光合速率与群体姜产量密切相关，群体光合速率决定于群体的构成。高产群体姜的单位面积分枝数应超过１５０／ｍ２，叶面积指数不得低于６ｍ２／ｍ２。本试验中种植密度超过７０００株／６６６．６７ｍ２的３个群体均达到了这一要求，这３个群体间的株高、分枝数、叶面积指数、群体光合速率和产量均无显著差异且都获得高产。姜群体光合速率的日变化呈典型的单峰曲线而异于单叶光合的双峰曲线。     

康复花园功能型植物景观设计——以昆明某公司“菊乐园”为例

为探讨康复花园所揭示的自然环境对人的正向作用,表明植物景观在保持和改善人们身心健康方面具有不可估量的功效,笔者结合植物景观在康复花园中的作用,提出康复花园功能型植物景观设计策略:(1)保健性原则;(2)营造感官体验区,强调植物景观具有的康复功效;(3)结合园艺疗法的实施;(4)因地制宜、适地适树。以昆明某公司"菊乐园"为例,着重介绍"菊乐园"功能型植物景观设计,以期为国内康复花园植物景观设计提供一定的理论和实践基础。     

陕北黄土区退耕还林（草）地土壤质量特征及其对降水的响应

为了解陕北黄土区退耕还林（草）地土壤质量差异特征及其对降水的响应,该研究沿370～470 mm的降水梯度,选取了陕西省吴起县境内的王洼子（370～395 mm）、大吉沟（440～445 mm）和白豹（460～470 mm）3个降水梯度区作为研究区,并结合土壤质量指数法,定量评价降水梯度区广泛栽植的刺槐林（Robinia pseudoacacia）、沙棘林（Hippophae rhamnoides）和草地的土壤物理结构、持水性、盐碱度、碳汇指标以及速效养分指标方面的综合得分,明确植被恢复后土壤质量随降水梯度的变化特征。结果表明：1）降水量、植被类型以及二者的交互作用对土壤指标影响显著（P<0.05）。2）在460～470 mm降水量区,刺槐林对土壤质量改良效果最好,其土壤质量综合指数为0.829,其次为沙棘林（0.808）,二者土壤质量均达到肥沃水平,且差异不显著,草地土壤质量综合指数最低为0.679,土壤质量为较肥沃水平;在440～445 mm降水量区,刺槐林、沙棘林和草地的土壤质量综合指数分别为0.672、0.764和0.527,其中刺槐林和沙棘林下土壤质量达到较肥沃水平,草地土壤质量等级为中等水平;在370～395 mm降水量区,3种植被类型土壤质量综合指数由大到小表现为沙棘林（0.792）>刺槐林（0.433）>草地（0.270）,沙棘林土壤质量等级最高为较肥沃水平,其次为刺槐林和草地,二者土壤质量分别为中等水平和贫瘠水平。3）在370～470 mm降水梯度内,3种植被类型土壤质量综合指数均随着降水量的减少而降低,其中沙棘林土壤质量综合指数变异系数较低为2.34%,刺槐林和草地土壤质量综合指数变异系数较高,分别为25.27%和34.34%。该研究结果可为陕北黄土区不同降水梯度下的植被恢复与重建等林业生态工程实施提供数据支撑与理论支持。     

陕北黄土区退耕还林后不同植被类型土壤含水量动态研究

为了掌握陕北黄土区退耕还林后不同植被类型土壤含水量的时空变化特征,采用单因素方差分析和Duncan法多重比较对陕西吴起县不同降雨带分布的植被类型土壤含水量变化进行研究。结果表明：降雨量对草地土壤含水量具有重要的正向影响;坡位对撂荒地土壤含水量影响较小,而对小叶杨林地土壤含水量影响较大,不同坡位差异显著,且下坡位土壤含水量显著高于中坡位;不同林地土壤含水量存在显著差异,且研究区4种林地土壤含水量大小表现为混交林>山桃>沙棘>柠条;不同土地利用类型间,农田土壤含水量最高,其次为灌木林地,撂荒地土壤含水量最低。     

牛未成熟卵母细胞体外受精及染色体分析

收集不同供体牛的卵母细胞并分成两组。体外成熟培养16h为不完全成熟组；体外成熟培养24h为完全成熟组。结果显示，体外受精48h后，成熟组大部分胚胎发育到8细胞期和16细胞期，不完全成熟组的多数胚胎发育到2细胞期和4细胞期。染色体异常发生率显著高于成熟组。染色体异常表现为单倍体、多倍体和混合倍体。引起染色体异常发生的原因可能是由于精子穿入时透明带或卵母细胞膜的功能障碍所引起。     

新农村建设背景下观光农业发展思路

随着社会主义新农村建设的深入开展,我国农村面貌发生了重大改观,为促进观光农业发展提供了一个新契机.观光农业在带动农村经济增长、促进农村社会进步的同时,也存在着经营管理不规范、辐射带动能力不强、破坏资源环境、传导不良文化等与新农村建设相背离的问题.为此,经探讨提出在新农村建设背景下推动观光农业发展的对策建议.     

不同施肥情况下甘蔗叶片的光谱特征分析及叶绿素含量检测

In order to investigate the visible-NIR spectral features of the leaves of a sugarcane variety(ROC 22), the spectral reflectance and the chlorophyll content were measured in the laboratory, and their correlations were analyzed.Prediction models were built eventually.Results showed that the negative correlations with r greater than 0.8 was found in 527-578 nm and 701-731 nm between spectral reflectance and chlorophyll content.And the red edge position(REP) was also found having high correlation with chlorophyll content, with the highest r of 0.8442.In order to explore the most sensitive bands for normalized difference vegetation index(NDVI), 48471 NDVI values were computed with different wavebands for each sample and their correlations with chlorophyll were also analyzed.The distribution maps of NDVI and its correlations in a two-spectral-dimension space both indicated that the red bands had significant influence than the NIR bands.The suggested sensitive red range was 710-735 nm, especially 720-725 nm; and the sensitive NIR range was from 780-850 nm, which had the higher robustness.The chlorophyll predication model with NDVI(725 and 840 nm) in tillering stage had determination coefficients of 0.7386, and was recommended for guiding the subsequent ridging fertilization.     

Dietary docosahexaenoic acid decreased lipid accumulation via inducing adipocytes apoptosis of grass carp, <Emphasis Type="Italic">Ctenopharygodon idella</Emphasis>

The purpose of this study was to explore the mechanism of by which docosahexaenoic acid (DHA) inhibit the accumulation of adipose tissue lipid in grass carp (Ctenopharyngodon idella). We therefore designed two semi-purified diets, namely DHA-free (control) and DHA-supplemented, and fed them to grass carp (22.19 ± 1.76 g) for 3 and 6 weeks. DHA supplementation led to a significantly lower intraperitoneal fat index (IPFI) than that in the control group by reducing the number of adipocytes but significantly higher adipocyte size (P < 0.05). In the intraperitoneal adipose tissue, the DHA-fed group showed significantly higher peroxisome proliferator-activated receptor (PPAR)γ, CCAAT enhancer-binding protein (C/EBP)α, and sterol regulatory element-binding protein (SREBP)1c mRNA expression levels at both 3 and 6 weeks (P < 0.05). However, the ratio of the expression levels of B cell leukemia 2 (Bcl-2) and Bcl-2-associated X protein (Bax) was significantly lower in the DHA-fed group than in the control group (P < 0.05), and the protein expression levels of the apoptosis-related proteins caspase 3, caspase 8, and caspase 9 were also significantly higher (P < 0.05). Overall, although DHA promotes lipid synthesis, it is more likely that DHA could suppress the lipid accumulation in adipocytes of grass carp by inducing adipocyte apoptosis.     

生态足迹法在松嫩平原西部可持续发展研究中的应用

以松嫩平原西部为例,运用生态足迹模型,对1989年和2001年的可持续状况进行了量化研究和对比分析。采用相对指标法,首次对研究区10个县、市的可持续性进行分级。结果表明：12a中,松嫩平原西部整体的可持续性呈下降趋势。在分析生态赤字存在的原因基础上,提出了实现生态供给平衡的途径。