寿山石的品种简介

福建省福州市产出的寿山石由田坑石、水坑石、掘性石(坡积石)和山坑石组成。经初步统计,有田坑石16种,水坑石12种,掘性石(坡积石)18种,山坑石118种,合计164种。它们分别主要由迪开石或珍珠石或高岭石或绢云母或叶蜡石组成。     

High mortality of Zostera marina under high temperature regimes but minor effects of the invasive macroalgae Gracilaria vermiculophylla

The present study tested for density-dependent effects of the invasive drift macroalgae Gracilaria vermiculophylla (Ohmi) Papenfuss on growth and survival of the native eelgrass, Zostera marina L., under different temperature levels. Three weeks laboratory experiments were conducted in Odense, Denmark, combining three algae densities (control, low 1.9 kg WW m⁻², high 4.5 kg WW m⁻²) with typical Danish summer temperatures (18 °C) and elevated temperatures (21 °C and 27 °C). There was a significant effect of temperature on shoot survival with on average 68% mortality in the high temperature treatment but almost no mortality at the two lower temperatures. The higher mortality was probably caused by high sulphide levels in the sediment pore water (0.6 mmol l⁻¹ at 18 °C compared to 3.7 mmol l⁻¹ at 27 °C). Above-ground growth of the surviving shoots was also significantly affected by temperature, with leaf elongation rates being negatively affected, while the leaf plastochrone interval increased. Relative growth rate was significantly higher at 21 °C than at 18 °C or 27 °C, whereas rhizome elongation was significantly lowest at 27 °C. Elemental sulphur content in the plant tissues increased significantly with temperature and was up to 34 times higher (S⁰ in rhizomes) at 27 °C compared to the lower temperatures. In contrast to the temperature effects, cover by G. vermiculophylla did not cause significant effects on any seagrass responses. However, there was a (non-significant) negative effect of algal cover at the highest temperature, where the seagrass is already stressed. The latter results suggest that more studies should test for interaction effects between temperature and other anthropogenic stressors given that temperature is predicted to increase in the near future.     

玛曲草地垂穗披碱草物候变化及影响因子

通过对1985—2005年玛曲草地垂穗披碱草 (Elymus nutans) 物候变化及其影响因子分析,发现玛曲草地垂穗披碱草返青期略有推迟的趋势,推迟趋势为1.6 d/10 a,而抽穗、开花、种子成熟、黄枯等物候期均呈提前趋势,特别是抽穗、开花、种子成熟期明显提前,提前趋势分别为4.9 d/10 a,8.0 d/10 a,13.9 d/10 a。影响玛曲草地垂穗披碱草返青期推迟的主要因子是秋季降水量减少,夏季气温升高是导致玛曲草地垂穗披碱草抽穗、开花、种子成熟期提前的主要原因,秋季暖干化趋势是导致黄枯期提前的主要原因。     

Scenario Analysis on the Adaptation of Different Maize Varieties to Future Climate Change in Northeast China

Based on gridded meteorological data for the period 1981–2100 from the RegCM3 regional model, the changing trends of climatic resources in Northeast China are analyzed, and the distributions of maize varieties are accordingly adjusted. In order to explore the effects of different adaptation countermeasures on climatic productivity and meteorological suitability in the future, maize cultivars with resistance to high temperatures and/or drought are selected. The results show that, in the future, there is likely to be a significant increase in thermal resources, and potential atmospheric evaporation will increase correspondingly.Meanwhile, radiation is predicted to increase significantly during 2041–2070 in the growing season. However, changes in precipitation are unlikely to be sufficient enough to offset the intensification in atmospheric evaporation caused by the temperature increase. Water resources and high temperatures are found to be the two major factors constraining grain yield. The results also show that the warming climate will be favorable for maize production where thermal resources are already limited, such as in central and northern Heilongjiang Province and eastern Jilin Province; while in areas that are already relatively warm, such as Liaoning Province, climatic productivity will be reduced. The climatic productivity and the meteorological suitability of maize are found to improve when the planting of resistant varieties is modeled. The utilization of agricultural climatic resources through the adaptation countermeasures of maize varieties is to increase obviously with time. Specifically, maize with drought-resistant properties will have a marked influence on meteorological suitability during 2011–2070, with suitable areas expanding. During 2071–2100, those maize varieties with their upper limit of optimum temperature and maximum temperature increased by 2℃, or water requirement reduced to 94%, or upper limit of optimum temperature and maximum temperature increased by 1℃ and water requirement reduced to 98%, all exhibit significant differences in climatic potential productivity, compared to the present-day varieties. The meteorological suitability of maize is predicted to increase in some parts of Heilongjiang Provine, with the eastern boundary of the "unavailable" area shifting westward.     

不同生育期四合木抗氧化系统的变化及生境间差异

对不同生境四合木种群特征、根际土壤理化性质进行了比较分析,对不同生育期四合木抗氧化系统的变化和生境间差异性进行了探讨。结果表明:①不同生境四合木种群密度、盖度、年龄结构存在显著差异,且低山、台地、丘陵种群所处生境有利于幼苗更新,其密度和盖度均显著大于高平原和倾斜平原种群\.②不同生境四合木根际土壤理化性质存在显著差异。对其进行聚类分析分为两类:低山、台地、丘陵为一类（A类）;高平原、倾斜平原为一类（B类）\.方差分析表明,A类样地土壤营养元素（N、P、K）和微量元素（全Fe、Mn、Zn、B、Mo与有效量）、土壤有机质含量及土壤含水量都显著高于B类。③不同生境四合木体内MDA含量、抗氧化酶类SOD、POD、CAT、AsA-POD、GR活性和非酶抗氧化剂GSH、AsA含量均随5月（营养期）、6月（花期）、8月（果期）而不断升高,二者协同作用共同抵抗干旱胁迫诱导的氧化伤害。④不同生境四合木抗氧化系统存在差异性:A类样地受到的膜脂过氧化程度相对较低,其体内的抗氧化酶活性和抗氧化剂含量较低;而B类样地四合木根际土壤干旱程度较高,土壤偏贫瘠,植物体通过提高一定幅度的抗氧化酶活性和抗氧化剂含量以清除干旱导致的氧化伤害。     

无定河流域产沙量变化的淤地坝效应分析

无定河流域1971~1989年的年均流量、悬移质含沙量及输沙率比1954~1970年的明显变小,而月均水沙过程曲线也发生了明显变化。上述水沙过程的变化受到1970年以来人类活动的强烈影响,而淤地坝建设是主因。为探讨淤地坝的减沙效应,提出淤地坝有效减沙面积这一概念,并拟合了动态变化的淤地坝有效减沙面积与年份之间的关系,发现该关系曲线与无定河流域各年代产沙量的变化情况相符。自1990年以来无定河流域淤地坝有效减沙面积呈明显递减趋势,导致了自上世纪90年代以来该流域的产沙量出现增大现象。为了抑制该流域的产沙量,势必需要加大淤地坝建设的力度。如果想使该流域的产沙量逐渐减少,则至少要使流域内年淤地坝有效减沙面积逐年增加。     

Red deer in New Zealand: Game animal,economic resource or environmental pest?

The 150‐year history of red deer in New Zealand reflects changing relations between people and introduced animals and has involved recreational, environmental and commercial hunting. Hunters initially pursued red deer for recreation then for environmental control before the animals were subsumed into society's economic processes. After 1930, they were regarded as environmental pests and hunting was open to all. Commercial hunting started after World War II, when economic value redefined the relationship between red deer and people. Relations between people and red deer continued to evolve as New Zealanders generated progressively more refined understandings of nature and the place of introduced species in this country's diverse environments.     

贵州省黔南地区可利用降水资源的气候变化特征分析

利用1962～2011年贵州省黔南地区12个气象站的月降水和月平均气温资料,采用高桥浩一郎经验公式计算月蒸发量,根据水量平衡关系,得出各月的可利用降水量,分析黔南地区可利用降水量的变化趋势和地域分布特点,结果表明:近50年黔南年可利用降水呈现减少的态势;夏季和冬季呈现增多的趋势,春秋季节呈现减少的趋势;可利用降水在5～7月丰富,其中6月最为丰富,占全年的24%;可利用降水地域分布表现为中部偏西偏东丰富,南北偏少。     

基于地下水多变量空间聚类分析的变异性评价

在现存地下水监测网站中,观测站点分布的任意性、随意性和层次不清以及观测数据的冗余性等问题普遍存在,应用空间聚类原理,对所选研究区域廊坊地下水的监测点位及监测指标分别进行了空间聚类分析,对原始数据和经聚类处理后的数据分别进行了空间变异性评价,结果显示空间聚类分析是有效合理的。试图将空间变异性和空间聚类方法结合起来,为环境监测点的重新布置提供了理论依据,使提高监测效率与监测点的代表性、优化监测网格成为了可能;了解监测指标及监测点位在空间上的相关程度,为环境监测指标的确定提供理论依据,进而为环境管理、污染物控制以及环境资源的综合利用提供基础依据。