Evaluation of land reclamation and implications of ecological restoration for agro-pastoral ecotone: case study of Horqin Left Back Banner in China

The agro-pastoral ecotone has been recognized as the main distribution area of reserved land resource for cultivation. Accordingly, clarifying this assumption, as well as concerting land reclamation and ecological restoration, is important to ensure food security and environmental improvement in the agro-pastoral ecotone. We selected Horqin Left Back Banner(HLBB) as the subject of our case study. The landscape ecological security pattern of this area was determined using the minimum cumulative resistance model. Over-cultivation, quantity of reserved land resource for cultivation, and changes in landscape indexes before and after land use adjustment were then analyzed. Over-cultivation is a serious problem in the agro-pastoral ecotone. Reserved land resource for cultivation is less than that considered previously, and the area of reserved land resource for cultivation in HLBB only accounts for 11.50% of total uncultivated land. With regard to changes in landscape indexes, the adjusted land use pattern is effective for anti-desertification. The compensation standard for abandoned cultivated land should be improved and the comprehensive results of ‘Grain for Green' should be evaluated to further implement ecological restoration in the agro-pastoral ecotone.     

Experimental studies on the role of planktivorous fishes in the elimination ofMicrocystis bloom from Donghu Lake using enclosure method

The hypertrophic subtropic Donghu Lake's dense water bloom (of mainlyMicrocystis, Anabaena andOscillatoria) that occurred annually from the beginning of the 1970s, has disappeared since 1985. The influence of planktivorous fishes (silver and bighead carps) on the water bloom was studied for three years using the enclosure method. The enclosures stocked densely with bighead and/or silver carp were free of water bloom during the experimental period. The water bloom that appeared in the fish-free enclosures was completely eliminated in 10–20 days by introduction of silver and/or bighead carp(grass carp was not effective in controlling water bloom). This study showed clearly that grazing pressure by planktivorous fishes is a key factor in eliminating water bloom from the lake. This work was supported by FEBL (State Key Laboratory for Freshwater Ecology and Biotechnology of China) funds and by the National Natural Science Foundation of China (Grant No., 3937014).     

台湾海峡及其两岸的地球动力学环境

本文根据断层的力学性质、活动习性、褶皱、断陷盆地、平原、海湾的形成机理,火山活动、水系分布格局,震源机制解、地壳形变场、ＧＰＳ观测成果和ＥＤＭ（光电测距）资料等,对比研究了台湾海峡及其两岸现今的地球动力学环境。结果表明：台湾海峡处在北西方向引张的应力环境;台湾地区受到来自太平洋菲律宾海板块向北西方向的挤压和因台湾海峡下降而产生的向南东方向的挤压;福建沿海则受到印度板块向北向东的挤压和太平洋菲律宾海板块向北西方向的挤压以及台湾海峡下降而产生的向北西方向的挤压。     

POTENTIOMETRIC TITRATION OF CALCIUM IN SEAWATER

Atpasent,thestandardmethodfordetendningcalciuminseawateriscomPlexometrictitrationusingEGTA[ethyleneglycol-bis(2-adrinoethylether)-N,N,N',N'-tetraaceticacid]andGHAtelyoxal-bis(2-hydroxyanil)].ThisInethodwasfirStdeveopedbyTSunogaietal.(l968),sumrnarindbyKremling,andeditalinMethodsofSeawaterAnalySisbyGrasshoff(l983).AlthoughtheendpointreadingsinthismethodarenotquitCsharp,andrnaybeaffCCtedbyoveanstweather,withtheuseofcalctumISEasindicatingeledrode,SCEasreferenceeledrodeanddigitalvoltme…     

桂西北喀斯特山区人口分布特征及其与自然因素的关系

选择第六次全国人口普查的最小行政单位——乡（镇）为基本单元,利用Lorenz曲线和空间相关分析方法分析桂西北喀斯特山区乡（镇）级尺度下的人口空间分布特征,运用地理探测器方法探测自然因素单独和叠加作用后对区域人口空间分布的影响强度。结果表明： 乡（镇）级研究尺度下的人口空间分布具有不均衡性特征,呈现一般显著正相关和一定的聚集性; 各自然因素空间分布对人口分布的影响呈现显著差异,研究区西北和中南部没有喀斯特分布的乡镇,人口密度随有利于人类居住因素的增加而增加,但平均人口密度仅79人/km ²。东部和南部有喀斯特分布的乡镇,人口密度与自然因素空间分布并非简单的增减关系,其随喀斯特分布面积的变化呈现起伏波动。 地理探测器的因子探测结果显示对人口空间分布的影响强度最大的为海拔高度,交互探测结果显示,任意两个自然因素叠加交互作用后的影响强度呈现非线性增强和双因子增强。可见,桂西北喀斯特山区与其他地区类似,海拔高度是影响人口空间分布的最主要因素之一,但喀斯特山区的河网密度及特有的地质地貌等因素对其人口的空间分布具有较强的催化作用,与其他因素叠加交互作用可进一步加强对人口分布的影响。     

一块新发现月球陨石MIL090036的岩相学和矿物学

MIL090036是一块在南极新发现的月球陨石,属于斜长岩质月球角砾岩。本文对这块陨石开展了详细的岩石学、矿物学特征观察与研究。MIL090036月球陨石具有典型的碎屑结构。碎屑包括岩屑、矿屑和玻屑。岩屑类型有斜长岩岩屑、辉长质斜长岩岩屑、辉长岩岩屑、风化角砾岩岩屑、橄长岩岩屑、微斑熔融角砾岩岩屑、复合角砾岩岩屑等;矿屑有辉石、斜长石、橄榄石、钛铁矿等;玻屑主要为长石质。基质由玻璃质、重结晶的细粒矿物和矿屑胶结组成。辉长岩岩屑中的斜长石（An81-83）和斜长岩中的斜长石(An88-93)较其他碎屑中的斜长石(An90-98)贫钙。岩屑、矿屑和长石质玻屑中的辉石相对贫铁（Fs 12-35Wo3-44 En22-79）,而含玻璃质的辉长岩岩屑中的辉石（Fs37-65Wo10-29 En21-49）与基质中的辉石（Fs18-69Wo3-45 En14-50）相对富铁。辉长岩质斜长岩中辉石成分变化范围最小（Fs24-27Wo7-14 En59-69）。矿屑橄榄石和分布于基质中的橄榄石铁镁含量（Fo57-79）相对岩屑中的橄榄石(Fo67-77) 变化范围大。橄榄石Fe/Mn比值为47-83（平均76）、辉石Fe/Mn比值为76-112（平均73）,都与月球橄榄石和月球辉石一致。岩石结构、矿物模式组合和化学成分等特征表明MIL090036是来自Apollo和Luna采样范围外的样品。对MIL090036的矿物学、岩石学和化学成分的进一步研究将能够丰富我们对月表物质组成和演化的认识。     

γ射线噪Blazar天体中尘埃的作用

利用具有多波段谱指数及流量观测资料的５９ 个Ｂｌａｚａｒ 天体作为样本,我们研究了各波段流量之间,谱指数之间的可能的相关性。新的可能的限制已从理论上进行了深入地讨论。结果暗示：（１） 同步自康普顿机制是Ｂｌａｚａｒ 天体γ射线辐射的主要机制。（２） 相对论电子与吸收积盘热光子的逆康普顿散射是Ｂｌａｚａｒ 天体γ射线产生的另一个重要机制。（３）ＢＬＬａｃ 天体不是“纯非热辐射”的天体,它们也具有强的热辐射。     

Width of Radio-Loud and Radio-Quiet CMEs

In the present paper we report on the difference in angular sizes between radio-loud and radio-quiet CMEs. For this purpose we compiled these two samples of events using Wind/WAVES and SOHO/LASCO observations obtained during 1996 – 2005. We show that the radio-loud CMEs are almost twice as wide as the radio-quiet CMEs (considering expanding parts of CMEs). Furthermore, we show that the radio-quiet CMEs have a narrow expanding bright part with a large extended diffusive structure. These results were obtained by measuring the CME widths in three different ways.     

The Population Carrying Capacity of Waters Ecosystem in China

The study of waters ecosystem and their population carrying capacity demonstrates the role of these ecosystems in economic and social development and provides a theoretical basis for the management and allocation of aquatic ecosystems. In this study, the concept of waters ecosystem population carrying capacity was defined and developmental trends in the population carrying capacity of waters ecosystem in China were evaluated. Results show that waters ecosystem population carrying capacity in China increased from 0.176×10⁹ person year^-1 in 2000 to 0.255 ×10⁹ person year^-1 in 2010; the population carrying capacity of the standard sea remained at 0.2-0.3 person ha^-1; and the standard inland waters population carrying capacity increased from 1.8 to 3.2 person ha^-1. This analysis indicates notable regional difference in waters population carrying capacity. In southeastern coastal China and Yangtze River drainage areas where inland waters are widely distributed and aquaculture is developed, the population carrying capacity is higher; however, in northwest China where water resource are deficient and the distribution is relatively small, the waters population carrying capacity is low. The waters ecosystem population carrying capacity of China in 2030 was predicted and results indicate strong potential for increasing waters population carrying capacity.