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A.The Soils Since the goological formation of this mountainous area is quite uniform,a vertical distribution of soils is obviously observed. At the top of the mountain with an elevation of 8,500 feet,the podzolic soil is found. The process of podzolization is clearly shown by the translocation of clays,organic matter, and active aluminum from an upper to lower layer.The gray brown podzolic soil is distributed in areas ranging from 7,000 to 8,500 feet in elevation.It is developed under forest and has a... A.The Soils Since the goological formation of this mountainous area is quite uniform,a vertical distribution of soils is obviously observed. At the top of the mountain with an elevation of 8,500 feet,the podzolic soil is found. The process of podzolization is clearly shown by the translocation of clays,organic matter, and active aluminum from an upper to lower layer.The gray brown podzolic soil is distributed in areas ranging from 7,000 to 8,500 feet in elevation.It is developed under forest and has a surface covering of leaf litter and a surface soil with high content of organic matter.In places at an elevatin from 3,900 to 7,000 feet the yellow podzolic soil is dominant.At an elevation below 3,000 foot the red podzolic soil and the sketetal soil are fonnd. The analytical data of the soils of this area may be summarized as follows: 1.pH values of the soils:In the whole area,since the parent rock (gneiss) is poor in basic constituents,soils are all acid in reaction.The pH of the different horizons of the soils ranges from 4.0 to 5.5.The A_0 and A_1 horizons are usually less acid than B horizon,the A and B horizons are much more acid than the parent rock.This shows the leaching process of the soils under such a humid atmosphere. 2.Organic Matter of the soils:The organic matter content of the soils in this area is greatlg influenced by the kind of the vegetation cover.At an elevation of 8,500 feet, the soil developed under forest has 38.92% of organic matter in the A_1,while that under grass has only 11.08% of organic matter in the corresponding horizon.However as the vegetation cover is constant,the dopth of the A_1 and its organic matter content are evidently affected by the elevation.At an elevation of 3,000 feet,the A_1 horizon of the red podzolic soil is only 1 cm.in depth,and it has 3.37% of organic matter.At an elevation of 8,500 feet,howerver,the A_1 horizon of the podzolic soil is 7 cm.in depth, and it has 11.08% of organic matter.In addition,deposition of organic matter in the B horizon is clearly found in the podzolic soil,but it has not been seen in soils found at lower elevation. 3.Active aluminum of the soils:All the soils in this area are high in active aluminum. They contain from 20 to 16 p.p.m.of active aluminum.The content of active aluminum in the different horizons of the same profile has a very close relationship with the pH values of the corresponding horizon.The less acid the reaction the smaller is the amount of acitve aluminum.The active aluminum of the soil is usually higher in amount than that of the parent rock from which the soil is derived. 4.Available calcium magnesium,and potassium of the soils:All the soils are general- ly low in available calcium,magnesium,and potassium.The comparatively high content of these elements in the A horizon is derived from the leaves of the vegetation which are grown on that soil. 5.Available phosphorus of the soils:All the soils of this area are low in available phosphorus. 6.Available nitrate:All soils in this area are very low in nitrate. B.The Vegetation 1.The plants growing on soils of this area are most calcifuge species which are acid- loving (Vaughan and Wishe,1937).As far as the chemical analysis of the soil is concer- ned,those species may be assumed as not only acid-loving,buy also active aluminum- loving (Hutchinson,1943). 2.The distribution of the calcifuge plants In this area is apparently affected by the local climate in terms of elevation.Some of them (temperate plants) are confined to high elevation,others(tropical plants) being limited to low elevation,Two groups of the plants may be given as follows.Many of them are of the same species as those found in southwestern China (Hou,1944). (a) Plants mainly ocurring in areas at elevations from 7,000 to 8,500 foot (temperate plants): Pteridophyta: Destaedtia Scabra (Wall.) Moore Diranopteris linearis Under. Hicrioptris glauea Under. Hymenophyllum crispatum Wall. Hymenophyllum exsertum Wall. Lidsaya cultrata Sw. Lycopodium clavatum L. Plagiogyria pyphylla (Kunze) Mett. Pteridium aquilinum Wightianum Trym Pteris aspericaulis Wall. Flowering Plants: Castanopsis tribuloides A.DC. Lindera pulcherrima Bth. Osbeckia crinata Bth. Rhododendron arboreum Sm. Rhododendron grande Wight Pieris formosana D.Don Vaccinium refersceda HK. Vaccinium serrasum Wight (b) Plants mainly ocurring in areas at elevation from 1,000 to 3,000 feet (tropical plants): Pteridophyta: Adiantum philippense L. Blechnum orientale L. Aglaoorpha coronaus Copel Lycopodium cernum L. Nephrolepsis cordifolia Presl Tectaria spp. Polypodium ucidum Roxb. Flowering plants: Oxyspora paniculate DC. Themeda arundinacea Ridl. 1945年10月中旬,作者留印三月另一周,曾作三次野外调查,计包括印缅边区、恒河平原及喜马拉雅山东南麓等三区,茲先将大吉岭区调查结果,草成此文。调查区域大吉岭位于喜马拉雅山东南麓,在我国西藏边境,全区是山地,海拔自1000到9000尺不等,主为酸性的片麻岩地层,在拔海6500尺地点,年平均气温为56.3℉.,年雨量为122寸。土壤灰壤——灰棕壤组合:在拔海8500尺左右的山顶,灰壤见于草地上,而灰棕壤则发育在森林之下。灰棕壤——灰化黄壤组合:在拔海7000—8000尺地带,森林下仍是灰棕壤,而草地上则为灰化黄壤。灰化黄壤——粗骨土组合:在拔海1000—3000尺地带,片麻岩生成灰化红壤,酸性砂岩生成砾质土。全区土壤特征可归纳如下: (1)土壤 pH 值:全区因土壤母质为酸性片麻岩,各类土壤剖面亦为酸性反应;pH 值约自4.0至5.5。A_1层之 pH 值恒较 B 层为大,而土壤剖面内之 A 层及 B 层均较母岩之酸度为高。 (2)土壤有机质:从土壤有机质分析结果观之,显示植物种类对于土壤有机质之含量高低,有密切的关系,在拔海8500尺之地带,发育于森林下的灰棕壤,表土含有机质38.92%,而同处草类和蕨类植物... 1945年10月中旬,作者留印三月另一周,曾作三次野外调查,计包括印缅边区、恒河平原及喜马拉雅山东南麓等三区,茲先将大吉岭区调查结果,草成此文。调查区域大吉岭位于喜马拉雅山东南麓,在我国西藏边境,全区是山地,海拔自1000到9000尺不等,主为酸性的片麻岩地层,在拔海6500尺地点,年平均气温为56.3℉.,年雨量为122寸。土壤灰壤——灰棕壤组合:在拔海8500尺左右的山顶,灰壤见于草地上,而灰棕壤则发育在森林之下。灰棕壤——灰化黄壤组合:在拔海7000—8000尺地带,森林下仍是灰棕壤,而草地上则为灰化黄壤。灰化黄壤——粗骨土组合:在拔海1000—3000尺地带,片麻岩生成灰化红壤,酸性砂岩生成砾质土。全区土壤特征可归纳如下: (1)土壤 pH 值:全区因土壤母质为酸性片麻岩,各类土壤剖面亦为酸性反应;pH 值约自4.0至5.5。A_1层之 pH 值恒较 B 层为大,而土壤剖面内之 A 层及 B 层均较母岩之酸度为高。 (2)土壤有机质:从土壤有机质分析结果观之,显示植物种类对于土壤有机质之含量高低,有密切的关系,在拔海8500尺之地带,发育于森林下的灰棕壤,表土含有机质38.92%,而同处草类和蕨类植物发育下的灰壤的表土,仅含有机质11.08%,但在相同的植物环境下,拔海高度或局部气候,也是支配土壤有机质含量的重要因素,例如在拔海3000尺地带,长有草类的灰化红壤,仅有极薄之有机质层,该层有机质含量为3.37%,而在拔海8500尺地带,长有草类的灰壤,则有较厚层有机质,其含量为11.08%。 (3)可溶性铝质:全区土壤含有高量可溶性铝,大约自20至160 p.p.m.,其含量与 pH 值高低相关,土壤 pH 值愈酸,可溶性铝含量就愈高。 (4)可溶性钙镁及钾质:全区土壤之可溶性钙,镁及钾等之含量均较低,但就同一土壤剖面而言,富于有机质的 A。或 A_1层的钙镁和钾质,常较 B 层为高,此点显示此等成份是来自植物遗体,亦即指示土壤中有机质与肥力之关系。 (5)全区土壤有效磷含量均甚低。 (6)全区土壤硝酸态氮之含量均极低,并有下淋现象。植物本文所论植物,仅以作者所采集而经各专家鉴定为限,其中以蕨类植物为主。本区的土壤都是酸性反应,所见的植物是以嫌钙性者为主,这些嫌钙性植物与拔海高度的关系很显著,兹将常见的植物种类,叙述如下: (一)主分布于拔海7000—8500尺地带的植物: 蕨类植物 Dennstaedtia scabra(Wall.)Moore Dicranopteris linearis Under. Hicriopteris glauca Under. Hymenophyllum crispatum Wall. Hymenophyllum exsertum Wall. Lindsaya cultrata Sw. Lycopodium clavatum L. Plagiogyria pycniphylla(Kunze)Mett. Pteridium aquilinum Wightianum Trym. Pteris aspericaulis Wall.种子植物 Castanopsis tribuloides A.DC. Lindera pulcherrima Bth. Osbeckia crinata Bth. Rhododendron arboreum Sm. Rhododendron grande Wight Pieris formosana D.Don Vaccinium referesceda HK. Vaccinium Serrasm Wight(二)主分布于1000—3000尺地带的植物: 蕨类植物Adiantum philippense L.Blechnum orientale L.Aglaomorpha coron(?)us copelLycopodium cernuum L.Nephrolepsis cordifolia PresslTectaria spp.Polypodium lucidum Roxb.种子植物Oxysoira paniculata DC.Themedra arundinacea Ridl. 1. In order to study the distribution of the two species of bedbugs,Cimex lectularius and C. hemiptera, 81 representative localities of 23provinces and Inner Mongolia were selected for the collection ofbedbugs.2. Among the 81 localities, 55 had only C. lectularius, 11 had onlyC. hemiptera, while the remaining 15 localities had both species.3. Atmospheric temperature forms one of the most important factorslimiting the distribution of bedbugs. Consequently C. hemipteralimits itself in the North at Chian-Yang of... 1. In order to study the distribution of the two species of bedbugs,Cimex lectularius and C. hemiptera, 81 representative localities of 23provinces and Inner Mongolia were selected for the collection ofbedbugs.2. Among the 81 localities, 55 had only C. lectularius, 11 had onlyC. hemiptera, while the remaining 15 localities had both species.3. Atmospheric temperature forms one of the most important factorslimiting the distribution of bedbugs. Consequently C. hemipteralimits itself in the North at Chian-Yang of Fukien, Lo-Chang ofKuangtung, Heng-Yang of Hunan, Tsun-I of Kweichow, Ch'eng-Tuof Szechuan and Ya-An of Sik'ang. In these localities the wintertemperature is usually at 4°- 8℃. North of this belt, because thewinter temperature is much lower, the condition is not suitable forthe existence of this species. Cimex lectularius is more resistant tocold. It is, however, less resistant to extreme heat. In localities inSouth China where the summer temperature runs over 30℃, thecondition is not suitable for the survival of this species. Its southernlimit of distribution has been found to be a line connecting Amoy,Chu-Kiang of Kuangtung, Kwei-Lin of Kuangsi, P'ing-T'ang of Kwei-chow and Meng-Tze of Yunnan.4. The relationship of latitude, altitude, atmospheric pressure andhumidity to the biology of bedbugs were briefly discussed. (一)作者在1950—1951年,曾收集中国81个地区的臭虫标本,作一系统的调查研究,这81个地区包括23省和内蒙古自治区。 (二)在81个地区所采集到的标本,有55个地区只有温带臭虫,44个地区只有热带臭虫,其余15个地区两种臭虫均有发生。 (三)气温是影响臭虫分布的重要因素之一。热带臭虫的分布,北至福建的建阳,广东的乐昌,湖南的衡阳,贵州的遵义,四川的成都(李、孟1951),西康的雅安,这些地区的冬季气温大都在4°—8℃。在这些北分布地区以北的地区,冬季气温较低,大多不适于它的生长,温带臭虫的抗寒力较强,在华北、东北、西北均有发生,它的分布南至福建的厦门,广东的曲江、广西的桂林、贵州的平塘(李、孟1951)、云南的蒙自,这些地区夏季气温均在30℃以下,仍可适于它的生长。 (四)地理上的经度与臭虫的分布并无关系,但纬度与臭虫的分布有关,热带臭虫的分布北至北纬30°41″(成都),它的发生地带以热带为主,在亚热带亦可生长,温带臭虫的分布南至北纬23°25′(蒙自),它的发生地带以亚热带及温带为主但传入部分的热带地区,亦可生长。 (五)地势过高可以影响热带臭虫的发生,在昆明、大理、昭通、... (一)作者在1950—1951年,曾收集中国81个地区的臭虫标本,作一系统的调查研究,这81个地区包括23省和内蒙古自治区。 (二)在81个地区所采集到的标本,有55个地区只有温带臭虫,44个地区只有热带臭虫,其余15个地区两种臭虫均有发生。 (三)气温是影响臭虫分布的重要因素之一。热带臭虫的分布,北至福建的建阳,广东的乐昌,湖南的衡阳,贵州的遵义,四川的成都(李、孟1951),西康的雅安,这些地区的冬季气温大都在4°—8℃。在这些北分布地区以北的地区,冬季气温较低,大多不适于它的生长,温带臭虫的抗寒力较强,在华北、东北、西北均有发生,它的分布南至福建的厦门,广东的曲江、广西的桂林、贵州的平塘(李、孟1951)、云南的蒙自,这些地区夏季气温均在30℃以下,仍可适于它的生长。 (四)地理上的经度与臭虫的分布并无关系,但纬度与臭虫的分布有关,热带臭虫的分布北至北纬30°41″(成都),它的发生地带以热带为主,在亚热带亦可生长,温带臭虫的分布南至北纬23°25′(蒙自),它的发生地带以亚热带及温带为主但传入部分的热带地区,亦可生长。 (五)地势过高可以影响热带臭虫的发生,在昆明、大理、昭通、丽江等地,拔海高度均在1922米以上,热带臭虫并无发生,但对温带臭虫并不影响。 (六)气压与地势的高低有关,昆明、大理,昭通、丽 Coilia mystus (L.) is a small fish of economic importance, belonging to the Family Engraulidae. It occurs abundantly along the coast of Amoy and vicinity. The present investigation was undertaken with the chief object of finding out the compostion of food and its seasonal variation. A total of 612 stomachs were examined; of these, only 22 stomachs were found to be empty. The following are the results of the investigation:(1) Coilia mystus feeds chiefly upon planktonic Crustacea, of which Copepoda is, by far,... Coilia mystus (L.) is a small fish of economic importance, belonging to the Family Engraulidae. It occurs abundantly along the coast of Amoy and vicinity. The present investigation was undertaken with the chief object of finding out the compostion of food and its seasonal variation. A total of 612 stomachs were examined; of these, only 22 stomachs were found to be empty. The following are the results of the investigation:(1) Coilia mystus feeds chiefly upon planktonic Crustacea, of which Copepoda is, by far, the most important, constituting no less than 75.9% of total food. Of the 15 species of Copepoda identified, Paracalanus pqrvus, Pseudodiaptomus marinus and Tortanus forcipata are relatively more important than the others. Among other Crustacea, the relative importance of various groups Is of the following order: Decapoda (including Lucifer and Brachyuran larvae) > Mysidae > Euphau-siacea > Amphipoda > Ostracoda > Cumacea > Stomatopoda. Next to Crustacea in the order of importance of food conic Chaetognatha and fish ova, the former being the more important of the two. Judging from the composition of food, Coilia mystus is a plankton-feeder.(2) The composition of food is more or less subject to seasonal variation. The order of numerical importance of various groups* in the four seasons is as follows: SPRING (Mar.-May): Copepoda > fish ova > Decapoda > Amphipoda > Mysidae> Euphausiacea > Cumacea> Stomatopoda, young fish. SUMMER (Junc-Aug.): Copcpoda> fish ova> Decapoda >Mysidae> Amphipoda> Euphausiacea > Cumacea > young fish.AUTUMN (Scpt.-Nov.): Copepoda > Decapoda > Mysidae > Ostracoda > Euphausiacea > Amphipoda > Stomatopoda > young fish.WINTER (Dec.-Feb.): Copepoda > Decapoda > Euphausiacea > Cumacea > fishova > Mysidae > Amphipoda > young fish > Stomatopoda. (3) The composition of food varies with age or length (from the tip of snout to the end of body, exclusive of caudal fin) of fish which appears to he related to the density of gill-rakers. The younger fishes (less than 15 cm. in length) with denser gill-rakers (2.0-2.7 rakers per 1 mm.) feed largely upon smaller crustaceans (Cope-poda); whilst the older fishes (over 15 cm. in length) with sparser gill-rakers (1.4 1.9 rakers per 1 mm.) feed largely upon larger crustaceans (Mysidae, Euphausiacea, Stomatopdda, Decapoda). It shows that increase in the size of fish is associated with increrase in the size of food animals eaten.(4) There exists a fairly close agreement between the composition of food and the composition of plankton in the surrounding waters. During the months of March and November when both fish and plankton were collected at the same time off Hai-Chen near Amoy, Copepoda was found to be the most dominant group in both food and plankton. It shows that the fish fed heavily upon those crustaceans occurring most abundantly in the plankton. In this respect, Coilia mystus exercises no selectivity of food. The writers are of the opinion that abundance and availability rather than selection by the fish determine the species of animal eaten.(5) A comparison of the food of Coilia mystus with that of other Clupeoids in Amoy waters reveals the predominance of Copepoda in the diet of most of these fishes. For the sake of increasing the yield of these economic fishes, it is essential to enhance the production of Copepoda in nature by artificial means such as to fertilize the water with nutrient salts, especially phosphates and nitrates, to increase the production of phytoplankton which will, in turn, lead to the higher production of Copepoda. 1.六丝鲚的食料差不多完全是浮游动物,以甲壳类为主,其中以桡足类为最重要、十足类(包括莹虾)次之,糠虾类,端足类,磷虾类更次之。除甲壳类以外,它还捕食很多毛头类和鱼卵,所以六丝鲚应属蜉食性的鱼类。 2.六丝鲚的食料成份有季节变化,不过不很显著:春夏两季以桡足类为主,鱼卵次之,十足类(包括短尾类幼虫)更次之。秋季以桡足类为主,十足类(包括莹虾和短尾类幼虫)次之,糠虾更次之。冬季以桡足类为主,十足类次之,磷虾类更次之。总的来看,桡足类在四季食料中都占了绝对优势。六丝的次要食料则随季节而异;春夏两季是鱼卵,秋冬两季都是十足类。值得注意的是:糠虾类和介壳类在秋季食料中的比率增加,磷虾类在冬季食料中占相当重要位置。食料的季节变化是和浮游生物的季节变化分不开的。 3.食料种类大小和体长有关:体长在15厘米以上的捕食较大的甲壳类(如磷虾类,口脚类和十足类等),而体长在15厘米以下的则捕食较小的甲壳类(如桡足类)。这和鳃耙密度有关:前者的鳃耙较稀(1毫米长中有1.4—1.9鳃耙)而后者的鳃耙较密(1毫米中有2.0—2.7鳃耙)。 4.食料和浮游生物存在着一定关系;在浮游生物中占... 1.六丝鲚的食料差不多完全是浮游动物,以甲壳类为主,其中以桡足类为最重要、十足类(包括莹虾)次之,糠虾类,端足类,磷虾类更次之。除甲壳类以外,它还捕食很多毛头类和鱼卵,所以六丝鲚应属蜉食性的鱼类。 2.六丝鲚的食料成份有季节变化,不过不很显著:春夏两季以桡足类为主,鱼卵次之,十足类(包括短尾类幼虫)更次之。秋季以桡足类为主,十足类(包括莹虾和短尾类幼虫)次之,糠虾更次之。冬季以桡足类为主,十足类次之,磷虾类更次之。总的来看,桡足类在四季食料中都占了绝对优势。六丝的次要食料则随季节而异;春夏两季是鱼卵,秋冬两季都是十足类。值得注意的是:糠虾类和介壳类在秋季食料中的比率增加,磷虾类在冬季食料中占相当重要位置。食料的季节变化是和浮游生物的季节变化分不开的。 3.食料种类大小和体长有关:体长在15厘米以上的捕食较大的甲壳类(如磷虾类,口脚类和十足类等),而体长在15厘米以下的则捕食较小的甲壳类(如桡足类)。这和鳃耙密度有关:前者的鳃耙较稀(1毫米长中有1.4—1.9鳃耙)而后者的鳃耙较密(1毫米中有2.0—2.7鳃耙)。 4.食料和浮游生物存在着一定关系;在浮游生物中占优势的种类也同样地在食料中占优势。桡足类便是一个很显著例子。其他甲壳类也有相似情况。可是水母则不然,它在浮游生物中很
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