川黔边土家族历史发展概述

湘鄂川黔边土家族历来就是一个整体,无论族源或基本特征均有其显然可见的共性。但由于历史上的某些原因,川黔边土家族又有其不同于一般的个性。研究这一问题,既要看到其共性,又要看到其个性,方能掌握住川黔边土家族历史发展的源与流,以及二者交汇中所展现出的特有风貌。一从唐代起关于湘鄂川黔边土家族先民的记载较前大为清晰了,研究历史以此作为起点其好处不言而喻。要解决川黔边土家族先民的族属问题,必须对两对族称加以注意.

Optimization of Field Arrangement of Doublecropping Glutinous Sorghum and Soybean Intercropping Pattern

In order to reduce successive cropping obstacles, optimize field arrange-ment of double-cropping of sorghum and soybean and improve yields, the research used Guojiaohong No.1 and Nandou No.12 as raw materials to explore the effects of different field arrangements on yield and benefits of double-cropping. The results indicated that with the double-cropping, both of gross yield and output value were higher compared with single-cropping treatments; yield, thousand-grain weight, the weight of grain per ear, and ear length of the 1st-season glutinous sorghum de-creased as compartment width grew, and of regenerated sorghum and soybean changed from increasing to decreasing. Specifical y, with double-cropping system, gross yield of glutinous sorghum reached the highest at 8 352.9 kg/hm2 with com-partment width of 1.7 m and soybean yield the highest at 1 888.95 kg/hm2 with compartment width of 1.8 m. Additional y, gross output value and net incomes achieved the highest at 47 293.92 yuan/hm2 and 29 976.42 kg/hm2 for the two crops, with compartment width of 1.7 m, fol owed by the treatment with compart-ment width of 1.8 m. In general, the treatments with compartment widths of 1.7 and 1.8 m are optimal field arrangement. Additional y, output-to-input ratio was the high-est in the treatment with single-cropping glutinous sorghum and the least in the treatment with single-cropping soybeans.

旱作丰5EC防除大豆田禾本科杂草药效试验

旱作丰(quizalofop P ethyl)5EC每公顷用商品量600～750ml,在大豆田禾本科杂草2～5叶期用药1次,速效性好,防效高达94.5%～95.8%,大豆增产34.6%～38.3%,且对大豆安全。

Effects of Different Factors on Biological Yield of Fodder Soybean(Glycine max(L.) Merr.) in Autumn Idle Land

Objective] The alm was to study the high-yield cuItivation technique of fodder soybean（Glycine max （L.） Merr.） in autumn idIe Iand. [Methods] Such five in-fIuencing factors as Iine spacing, pIanting density, nitrogen （N）, phosphorus （P） and potassium （K） of fodder soybean seeding in autumn idIe Iand were compared using orthogonal experiment method and LSD method of PASW 18 statistics software. [Results] The resuIts showed that density, Iine spacing and K2O had important ef-fects on bioIogical yield of fodder soybean in autumn idIe Iand. Moreover, the opti-mum proposal for high-yield matching cuItivation technique of fodder soybean in au-tumn idIe Iand was determined as foI ows： pIanting density was 75 ＆#215;104 pIants/hm2;300 kg/hm2 N, 112.5 kg/hm2 P2O5 and 375 kg/hm2 K2O were viewed as basic fertiIiz-ers; the seedIing styIe was sowing in driI with the Iine spacing of 50 cm. In the proposal, fresh and hay grass yields were 6 661.67 and 2 723.64 kg/hm2, respec-tiveIy, which increased by 24.17% and 27.63% respectiveIy compared to the second fine combination. [Conclusions] The resuIts provided a theoretical basis and technical support for the production of fodder soybean in autumn idIe Iand.

Zinc Application Affects Tissue Zinc Concentration and Seed Yield of Pea(Pisum sativum L.)

A 2-year field experiment was conducted to assess the effect of applied zinc(Zn) on the seed yield of pea(Pisum sativum L.) and to determine the internal Zn requirement of pea with emphasis on the seed and leaves as index tissues.The experiment was carried out at two different locations(Talagang,Chakwal district and National Agricultural Research Centre(NARC),Islamabad) in the Potohar Plateau,Pakistan by growing three pea cultivars(Green feast,Climax,and Meteor).The soils were fertilized with 0,2,4,8,and 16 kg Zn ha^(-1) along with recommended basal fertilization of nitrogen(N),phosphorus(P),potassium(K),and boron(B).Zinc application increased seed yield significantly for all the three cultivars.Maximum increase in the pea seed yield(2-year mean) was21%and 15%for Green feast,28%and 21%for Climax,and 34%and 26%for Meteor at Talagang and NARC,respectively.In all cultivars,Zn concentrations in leaves and seed increased to varying extents as a result of Zn application.Fertiliser Zn requirement for near-maximum seed yield varied from 3.2 to 5.3 kg ha^(-1) for different cultivars.Zinc concentrations of leaves and seeds appeared to be a good indicator of soil Zn availability.The critical Zn concentration range sufficient for 95%maximum yield(internal Zn requirement)was 42-53 mg kg^(-1) in the pea leaves and 45-60 mg kg^(-1) in the seeds of the three pea cultivars studied.

Emergy assessment of three home courtyard agriculture production systems in Tibet Autonomous Region, China

Home courtyard agriculture is an important model of agricultural production on the Tibetan plateau. Be- cause of the sensitive and fragile plateau environment, it needs to have optimal performance characteristics, including high sustainability, low environmental pressure, and high economic benefit. Emergy analysis is a promising tool for evaluation of the environmental-economic performance of these production systems. In this study, emergy analysis was used to evaluate three courtyard agricultural production models： Raising Geese in Corn Fields （RGICF）, Con- ventional Corn Planting （CCP）, and Pea-Wheat Rotation （PWR）. The results showed that the RGICF model produced greater economic benefits, and had higher sustainability, lower environmental pressure, and higher product safety than the CCP and PWR models. The emergy yield ratio （EYR） and emergy self-support ratio （ESR） of RGICF were 0.66 and 0.11, respectively, lower than those of the CCP production model, and 0.99 and 0.08, respectively, lower than those of the PWR production model. The impact of RGICF （1.45） on the environment was lower than that of CCP （2.26） and PWR （2.46）. The emergy sustainable indices （ESIs） of RGICF were 1.07 and 1.02 times higher than those of CCP and PWR, respectively. With regard to the emergy index of product safety （EIPS）, RGICF had a higher safety index than those of CCP and PWR. Overall, our results suggest that the RGICF model is advantageous and provides higher environmental benefits than the CCP and PWR systems.

Minimum Data Set for Assessing Soil Quality in Farmland of Northeast China

Soil quality assessment provides a tool for agriculture managers and policy makers to gain a better understanding of how various agricultural systems affect soil resources. Soil quality of Hailun County, a typical soybean （Glycine max L. Merill） growing area located in Northeast China, was evaluated using soil quality index （SQI） methods. Each SQI was computed using a minimum data set （MDS） selected using principal components analysis （PCA） as a data reduction technique. Eight MDS indicators were selected from 20 physical and chemical soil measurements. The MDS accounted for 74.9% of the total variance in the total data set （TDS）. The SQI values for 88 soil samples were evaluated with linear scoring techniques and various weight methods. The results showed that SQI values correlated well with soybean yield （r = 0.658＊＊） when indicators in MDS were weighted by the regression coefficient computed for each yield and index. Stepwise regression between yield and principal components （PCs） indicated that available boron （AvB）, available phosphorus （AvP）, available potassium （AvK）, available iron （AvFe） and texture were the main factors limiting soybean yield. The method used to select an MDS could not only appropriately assess soil quality but also be used as a powerful tool for soil nutrient diagnosis at the regional level.