Satellite estimate of grass biomass in a mountainous range in central Italy

One of the main problems in managing ranges used for extensive pastoralism is the difficulty of obtaining reliable estimates of grass biomass over very large areas. Estimates of grass biomass are useful as an indicator of both available forage and risk of soil erosion. Nevertheless, large scale field measurements are expensive and time-consuming. The use of satellite images may provide a complementary means of estimating grass biomass over very large areas at a reasonable cost. The aim of this study was to test the use of Landsat satellite data for estimating grass biomass in a mountainous range in central Italy used primarily for sheep breeding. During each of four ground campaigns carried out over two years, grass was cut and its biomass measured in 60-90 test plots. Four Landsat images taken simultaneously to the ground campaigns were processed to obtain several vegetation indexes calculated for each ground test plot. The vegetation indexes showed significant correlations with measured grass biomass. The Normalized Difference Vegetation Index (NDVI) provided the most accurate estimate of grass biomass. When data for each of the four ground campaigns were analyzed separately, correlations for early summer campaigns were higher than correlations for late summer campaigns, indicating that when the ratio of dry/green biomass increases, satellite estimate becomes less accurate. Overall, our results show that satellite data can provide a useful source of biomass information for the management of large ranges. This revised version was published online in June 2006 with corrections to the Cover Date.     

蛾类栗实害虫的识别

本文从形态学的角度对在浙江省板栗果实上危害的五种蛾类进行了描述，并编制了简明实用的幼虫林间检索表和蛹林间检索表。     

基于Landsat 8和随机森林的青海门源天然草地地上生物量遥感估算

草地地上生物量（above-ground biomass, AGB）的遥感监测可快速且客观地对草地生长现状进行评估,对生态环境评价和草地资源利用有重要意义。为了提高遥感估算草地AGB的准确性,基于青海省门源县的地面实测数据,利用Landsat-8 OLI遥感数据计算出的植被指数分别构建了单因素回归模型和随机森林模型（random forest, RF）,确定了AGB遥感估测最佳模型,并反演得到了研究区2019-2021年草地AGB空间分布。结果表明：1）在29个植被指数构建的单因素回归模型中,与草地AGB相关性较高的5个植被指数为NDVI、RBNDVI、TVI、GNDVI、MSR,R²均达0.49以上。其中,NDVI模型的精度最高,验证集R²为0.50,均方根误差（root mean square error, RMSE）为702.89 kg·hm^-2。2）在RF模型中,变量筛选前R²=0.61,RMSE=621.14 kg·hm^-2;经过变量筛选后模型精度有小幅度提升,R²达0.62,RMSE基本不变;二者精度均优于单因素模型,相比传统单因素最优回归模型,R²提高0.12,RMSE降低了80.95 kg·hm^-2。3）门源县AGB空间分布特征为西北部较高,东南部相对较低;大体呈中部高,四周低的分布状况。2019-2021年全县天然草地总产草量介于4.2827万~8.9776 万t,平均单产介于1063.49~1484.82 kg·hm^-2;草地类型以高寒草甸为主,2019-2021年产草量为4.0825万~5.6653 万t,平均地上AGB介于1060.38~1471.94 kg·hm^-2;山地草甸平均AGB为1036.81~1637.43 kg·hm^-2;温性草原平均AGB介于1198.72~1786.63 kg·hm^-2。     

Interventional effects of tongxinluo combined with atorvastatin and aspirin on adventitial inflammation in early stage of atherosclerosis

AIM: To investigate the effect of a treatment proposal, which consisted of tongxinluo, atorvastatin and aspirin, on adventitial inflammation of early atherosclerosis in rabbit carotid artery. METHODS: The atherosclerotic model was established in the rabbits with silicone collar, which was positioned around the carotid arterial adventitia+high-cholesterol diet. New Zealand rabbits (n=72) were randomly divided into 6 groups (n=12): control group, model group, tongxinluo group, atorvastatin group, aspirin group, and three-drug combination group. The rabbits in control group were fed with common foodstuffs, and the rabbits in all the other groups were fixed the right carotid arteries with the silicone tube, and were fed with fatty foodstuffs. The rabbits in tongxinluo group, atorvastatin group and aspirin group were given the suspension of tongxinluo supermicropowder (0.3 g·kg^-1·d^-1), atorvastatin (2.5 mg·kg^-1·d^-1) and aspirin (12 mg·kg^-1·d^-1) respectively,and the rabbits in three-drug combination group were given the suspension of tongxinluo supermicropowder (0.3 g·kg^-1·d^-1), atorvastatin (2.5 mg·kg^-1·d^-1) and aspirin (12 mg·kg^-1·d^-1) together. The rabbits in each group were fed with the corresponding medicines for 4 weeks. The tissue slices of carotid artery were observed under light microscope with HE staining. The change of blood lipid was detected by biochemical assay. The protein levels of MCP-1, IL-1β and IL-10 in the carotid arterial adventitia were detected by ELISA. The immunohistochemical staining was used to detect the protein expression of IL-8 around the carotid arterial adventitia.RESULTS: Compared with control group, the contents of TC, TG and LDL-C were significantly increased, and the content of IL-10 was significantly decreased in model group. The levels of TC, TG and LDL-C were significantly decreased in tongxinluo group and atorvastatin group compared with model group, no significant difference between tongxinluo group and atorvastatin group was observed. In the three-drug combination group, the levels of TC, TG and LDL-C were lower than those in atorvastatin group and tongxinluo group. Compared with control group, the contents of MCP-1 and IL-1β were significantly increased, and the content of IL-10 was significantly decreased in model group. Compared with model group, the contents of MCP-1 and IL-1β were decreased in tongxinluo group, atorvastatin group and aspirin group, no significant difference between the 3 groups was observed. The content of IL-10 was decreased in three-drug combination group, and the contents of TC, TG and LDL-C were lower than those in tongxinluo group, atorvastatin group and aspirin group. The content of IL-8 was decreased in tongxinluo group, atorvastatin group, aspirin group and three-drug combination group.CONCLUSION: The strategy of three-drug combination enhances the effect of regulating the lipid metabolism and inhibiting the adventitia inflammation. It plays an important role to intervene in the process of atherosclerosis.     

Influence of the probiotic Bacillus cereus var. toyoi on the intestinal immunity of piglets

In a feeding trial, sows and piglets were fed with the probiotic bacterium Bacillus cereus var. toyoi as a feed additive, and the effects on immune cell populations were examined. The development of the gut immune system was determined for piglets at the ages of 14, 28, 35 and 56 days post partum. Tissue samples of the Jejunum and the continuous Peyer's patch were used for enumeration of intraepithelial lymphocyte populations by fluorescence activated flow cytometry and fluorescence microscopy. Both independent methods of investigation led to similar results: the population of intraepithelial CD8+ T cells was significantly enhanced in the probiotic group piglets (p ≤ 0.05), and the numbers of γδ T cells tended to be higher in the intestinal epithelium (p < 0.1) at the time of weaning (day 28). Lamina propria lymphocytes were also influenced by the treatment. Application of B. cereus var. toyoi resulted in significantly more CD25+ lymphocytes and γδ T cells in the probiotic group post-weaning. The occurrence of pathogenic Escherichia coli serogroups was also less frequent in the feces of piglets from the probiotic group. The finding that the CD8+ T cell population in the intestinal mucosa showed changes on day 28 indicated that the influence of B. cereus var. toyoi supplementation on the intestinal immune system started before weaning, an observation supported by changes in the intestinal microflora observed during the suckling-period. The results suggest that feeding of B. cereus var. toyoi to sows may result in beneficial effects on piglet health status independent of their feed supplementation.     

HRAP基因诱导型植物表达载体的构建及烟草转化

系统获得性抗性是植物抵御病菌侵染的一种独特的防御机制.HRAP基因是一种从甜胡椒中克隆的蛋白质激发子,可以有效引发植物系统性抗性.SAR8.2b基因是烟草系统获得性抗性信号传导途径中下游响应基因,受病原物和水杨酸诱导.本试验根据Genebank发布SAR8.2b基因的启动子序列,利用PCR技术,克隆了SAR8.2b基因的完整启动子,命名为SAR8.2bP,然后将SAR8.2bP构建到pUC18-HRAP载体中命名为pUC18-SAR8.2bP-HRAP,然后用SAR8.2bP-HRAP替换p2300-121载体中的35S启动子和GUS基因,重组子命名p2300-SAR8.2bP-HRAP.将构建的植物表达载体转化农杆菌GV3101,利用叶盘法转化烟草,通过PCR筛选,获得了转基因植株.为进一步验证转基因烟草的抗病效果奠定了基础.     

黄河中上游部分地区土地覆盖动态变化研究

作为美国国家科学基金项目"中国生态恢复综合影响评价"的部分研究结果,对项目选定的四个评价区之一的黄河中上游地区的研究区域进行土地利用和覆盖变化研究,并以此评价退耕还林效果。利用覆盖研究区域的卫星遥感图像进行解译,以便获取研究区域土地利用和土地覆盖变化(LUCC)的历史数据,特别是大于25度坡度的LUCC以及退耕前后的LUCC数据,通过这些解译数据评价研究区域的退耕还林效果。解译后的数据显示退耕还林效果良好。选定24景跨20年(1978年至2007年)的Landsat遥感卫星图像数据,通过解译追踪研究区域LUCC历史演变,来判断退耕还林的执行效果。     

A new proaporphine alkaloid from Meconopsishorridula

A new proaporphine alkaloid, 8, 9-dihydroprooxocryptochine (1), together with three known alkaloids, was isolated from the aerial parts of Meconopsishorridula Hook. f. & Thomson (Papaveraceae), a traditional Tibetan medicine. The structure of 1 was determined by spectroscopic methods.     

棉花新品种湘农棉8号的选育与栽培

湘农棉8号是由Sb（AB-21）×南引nm-1杂交选育而成．其母本Sb（AB-21）选自泗棉2号变异株×鄂引大桃选系材料,其父本南引nm-1来源于南引品种选系。2003年选配出强优势多抗杂交棉新组合Sbnm-7F1,经省区斌及同生态区多点大面积生产示范,并经农业部棉花品质监督检验测试中心检测分析及湖北省农业科学院经济作物研究所人工枯、黄萎病圃鉴定,表现优质高产,增产潜力大,适应性广,抗倒伏性强,抗枯萎病,耐黄萎病等特点。介绍了湘农棉8号的选育经过、特征特性和栽培技术;     

湘杂棉8号不同密度下性状及产量品质表现

对不同密度下湘杂拂8号农艺性状、产量构成和纤维品质进行研究。结果表明：果枝数、果节数、单株成铃数、成铃率均随着密度的增加而逐渐降低;12000株,hm^2处理的籽棉、皮棉产量,成铃数／hm^2最低。30000株/hm^2产量最高,39000株/hm^2次之,适宜密度为301300—39000株/hm^2;各处理间棉圩维平均长度、比强度、伸长率差异不显著,21000株／hm^2处理的整齐度最高,为85．19％。12000株/hm^2处理整齐度最低,为84．38％。