Effects of gully erosion and gully filling on soil degradation in the black soil region of Northeast China

Gully erosion has caused soil degradation and even reduced soil productivity.However,only few studies on the effects of gully erosion and artificial controlling measures on soil degradation in the Black Soil Region of Northeast China are available.Thus,this study explores the relationships between gully erosion,gully filling and soil parameters.Two sets of soil samples were collected in the field at:(1) 72 sample points in the gully erosion study area,60 sample points in the ephemeral and classical gully erosion area(3,518 m2),12 sample points in the deposition zone(443 m2),(2)10 reference points along a slope unaffected by gully erosion representing the original situation before the gully was formed.All soil samples were analyzed for gravel content(GC),soil organic matter(SOM),total nitrogen(TN),available nitrogen(AN),available phosphorus(AP),and available potassium(AK).The soil property values on unaffected slope were fitted by the polynomial curves as the reference values in no gully erosion area.The interpolated soil property values in gully eroded study area were compared with these polynomial curves,respectively,and then,changes of soil property values were analyzed.Gully erosion caused an increase in GC and a decrease in SOM,TN,AN,AP and AK.The change of GC,SOM,TN,AN,AP,AK was 8.8%,-9.04 g kg-1,-0.92 g kg-1,-62.28 mg kg-1,-29.61 mg kg-1,-79.68 mg kg-1.The soil property values in the study area were below optimal values.Thus,we concluded that gully erosion and gully filling caused both on-site and off-site soil degradation.Soil degradation area was 0.65 % of the cultivated land.In addition,it was proved that gully filling were an improper soil and water conservation measure,which seems to exacerbate the problem.Thus,it is suggested that soil where soil is deep is moved to fill the gully,and then the area around the filled gullies should be covered by grass for preventing the formation and development of the gully.     

加强非金属矿产在水污染防治中的应用研究

利用部分非金属矿产的特有性能处理污水,往往能取得事半功倍的效果。工业化国家在这方面的研究比较广泛和深入,而我国比较落后。因此,需要广大的环保、地矿科技人员迅速行动起来,加强非金属矿产在污水处理中的应用研究,以保护我们的水环境,造福于人民。     

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Rheological properties and structural changes in different sections of boiled abalone meat

1　Introduction　AbaloneHaliotisdiscusisaverypopularfoodthrough outtheworld .WhenAsianpeoples ,notablyJapaneseandChinese ,eatabalonedishes ,theyenjoythefirmtextureoftherawmeatandthetendernessoftheboiledmeat .InJapan ,thetoughervarietiesoftherawabalonemeatareenjoyedandtheabaloneisoftenthin lyslicedandservedraw (sashimi) ,whileinchina ,thetendernessandsoftervarietiesoflesscollagenofboiledmeatareconsideredsuitableforeating ,sotheabaloneisoftenservedbyheating .Infoodscience ,manyreportshavebeen …     

Antioxidant and isozyme features of two strains of Laminaria japonica （Phaeophyceae）

Healthy sporophytes of two gametophyte mutants of Laminaria japonica with different heat resistances: kelp 901 (901, with comparatively stronger heat-resistance) and Rongcheng No.1 (RC, sensi- tive to heat stress), were respectively collected during October to December 2002 from Yantai and Rong- cheng Sea Farm in the Shandong Peninsula of China. The contents of some biochemical materials and antioxidant capacity were analyzed under controlled laboratory conditions to identify if there is any rela- tion between the overall antioxidant capacity and the heat-resistance in L. japonica and to understand possible mechanism of heat-resistance. Results show that: (1) the overall antioxidant capacity in healthy sporophyte of 901, such as vitamin E, polyphenol, and ascorbic acid contents and the enzymatic activity of SOD, POD, CAT, Gpx, PPO, and PAL, were not always higher than that of RC under controlled labo- ratory conditions, and no significance (P>0.05) was shown in total antioxidant capacity (T-AOC) in 901 and RC. Result suggested that the difference in antioxidant capacity was not a decisive factor for different heat-resistances in L. japonica; (2) the simultaneous assay on isozymes was carried out using vertical polyacrylamide gel electrophoresis (PAGE). Considerable differences in peroxide (PRX), malate dehy- drogenase (MDH), malic enzyme (ME), polyphenol oxidase (PPO) and glutamate dehydrogenase (GDH) were obtained in 901 and RC from either the band number, relative mobility (Rf), or staining intensity, and ME could be used as an indicator to distinguish healthy sporophyte of 901 and RC under controlled labo- ratory conditions.     

景泰地震前后兰州台的中期形变异常

给出了兰州台浮子水管倾斜仪和石英伸缩仪１９８７～１９９３年间Ｍ２波潮汐因子的年度调和分析结果，然后对各分量月均值进行了残差分析，并绘出去除长期项后的倾斜矢量图，据此探讨了景泰地震的中期前兆异常和震后效应特征。     

湖南花岗斑岩型金矿找矿方向浅析——以桃江半边山花岗斑岩型金矿为例

本文以半边山花岗斑岩型金矿为例,通过分析其成矿地质特征、矿化富集规律和矿床成因,预测其矿床规模,并对花岗斑岩型金矿床的找矿方向进行了分析,为湖南寻找同类型金矿提供参考。     

中国第22和24次南极考察中山站越冬队员膳食调查

在南极中山站特殊环境下,膳食营养对人体的保护尤显重要。通过在中山站对第22和24次中国南极越冬队分别开展三次连续动态膳食调查,获取越冬队员的主要膳食模式,有针对性地提出改善膳食模式的建议,以保障越冬队员的健康。分别在2006年、2008年采用连续3—4天/次称重法对第22、24次中山站越冬队员进行三次膳食调查,计算平均每人每日能量及各种营养素摄入量,与《中国居民膳食营养素参考摄入量(Chinese DRIs)》进行对比分析、评价队员膳食营养状况。越冬队员平均能量摄入充足,符合中至重等体力劳动所需摄入量(2 700—3 200 kcal)。获得的17种营养素中,钙、维生素A、维生素C、微量元素硒的摄入量低于中国DRIs标准,钠摄入偏高,其余基本符合标准。烹调用油、食盐的摄入量超过中国营养学会建议的摄入量。脂肪、蛋白质提供的能量比(三大营养物质所提供的能量各占百分比)分别高于中国营养学会推荐的20%—30%、12%—14%,碳水化合物低于推荐的55%—65%。中山站越冬队员呈现高脂肪、高蛋白、低碳水化合物,烹调用油、食盐的摄入量过高,钠摄入偏高,以及维生素A、C和钙、硒摄入量过低的膳食结构。应调整脂肪、蛋白质、碳水化合物的摄入比例,调整烹调用油、钠盐的摄入量,补充维生素A、C和钙、硒。     

Phenological metrics-based crop classification using HJ-1 CCD images and Landsat 8 imagery

Crop type data are an important piece of information for many applications in agriculture. Extracting crop type using remote sensing is not easy because multiple crops are usually planted into small parcels with limited availability of satellite images due to weather conditions. In this research, we aim at producing crop maps for areas with abundant rainfall and small-sized parcels by making full use of Landsat 8 and HJ-1 charge-coupled device (CCD) data. We masked out non-vegetation areas by using Landsat 8 images and then extracted a crop map from a long-term time-series of HJ-1 CCD satellite images acquired at 30-m spatial resolution and two-day temporal resolution. To increase accuracy, four key phenological metrics of crops were extracted from time-series Normalized Difference Vegetation Index curves plotted from the HJ-1 CCD images. These phenological metrics were used to further identify each of the crop types with less, but easier to access, ancillary field survey data. We used crop area data from the Jingzhou statistical yearbook and 5.8-m spatial resolution ZY-3 satellite images to perform an accuracy assessment. The results show that our classification accuracy was 92% when compared with the highly accurate but limited ZY-3 images and matched up to 80% to the statistical crop areas.