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禾本科物种(例如银草、芦苇)在日本传统的地膜覆盖农业中普遍使用,西阿瓦地区是全球重要的农业遗产系统(GIAHS)所在地。传统上,这里的农民使用银草覆盖农业土壤。但当地农民从长期的经验中了解到,日本虎杖覆盖更适合该地区茄科作物的种植。目前尚不清楚日本虎杖覆盖物为何对茄科作物的种植有益。在本项研究中,我们假设日本虎杖覆盖物可能会有效避免连续种植马铃薯的危害。因为过去每年都会种植两次本地马铃薯,因此,我们调查了日本虎杖覆盖对连续种植马铃薯以及番茄种植后对马铃薯产量的影响。在2018年进行的田间试验中,我们首先在连续马铃薯栽培的土壤和未耕种的土壤中比较了日本虎杖覆盖、银草覆盖和无草覆盖(对照)对马铃薯产量的影响,结果表明日本虎杖覆盖减少了马铃薯产量的降低程度。其次,我们比较了番茄种植后的土壤和未耕种的土壤中的虎杖覆盖和无草覆盖对马铃薯产量的影响,结果再次表明了日本虎杖覆盖减少了马铃薯生长和产量下降的程度。这些发现表明用日本虎杖覆盖有助于避免连续种植马铃薯的风险。  相似文献   
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The metabasites within the Tokoro belt of eastern Hokkaido,Japan, suffered pervasive high–P/ Tetamorphism. Mineralassemblages and compositions of more than 400 metabasites fromthe Saroma–Tokoro district were investigated. The metabasites are divided into six metamorphic zones basedon mineral assemblages. The laumontite (Lm) zone is definedby the presence of laumontite. The prehnite–pumpellyite(Pr–Pp) zone is characterized by the association of prehnite+ pumpellyite. The lawsonite–sodic. pyroxene (Lw–Napx)zone is defined by the assemblage lawsonite + pumpellyite +sodic pyroxene + chlorite. The epidote–sodic pyroxene(Ep–Napx)(1) and (2) zones are charecterized by the assemblage epidote+ pumpellyite + sodic pyroxene + chlorite. The former is characterizedby the absence of aragonite, sodic amphibole, and winchite,as well as the presence of jadeite–poor sodic pyroxene(maxJd mol% = 13), whereas these minerals occur in the Ep–Napx(2)zone, together with jadeite–rich sodic pyroxene (max.Jd mol % = 34). In the epidote–actinolite (Ep–Act)zone, the most common assemblages contain epidote+ actionolite+ pumpellyite + chlorite. The Lm zone corresponds to the zeolite facies (150–200?Cand 1–2 kb) and the Pr–Pp zone is equivalent tothe prehnite–pumpellyite facies (200–250?C and 2–2–5kb). The Ep–Napx(I) zone appears to be stable at 200–250?C and 2? 5?3?5 kb. The pressure conditions in the Lw–Napx,Ep-Napx(2), and Ep–Act zones appear to range from 5 to6 kb, and the temperatures are estimated to be 200–230,230–270, and 270–300? C, respectively. The sequenceof the metamorphic zones is charaterized by the curved P–Tpath. The stability field of pumpellyite+ sodic+ pyroxene+ chloritein Fe3+ bearing metabasites is located in the lower–temperatureand higher–pressure part of the pumpellyite–actionolitefacies. On the basis of Schreinmaker's method, the stabilityfield of the assemblage is bounded by a high–pressurereaction Pp+ Napx+ Chl+ Ab+ Qz+ H2O= Lw+ Gl, and by a high-temperaturereaction Pp Napx+ Chl+ Ab+ Qz = Ep + Gl + H2O.  相似文献   
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ABSTRACT. Contemporary storytelling among the IÑupiat of Point Hope, Alaska, is a means of coping with the unpredictable future that climate change poses. Arctic climate change impacts IÑupiat lifeways on a cultural level by threatening their homeland, their sense of place, and their respect for the bowhead whale that is the basis of their cultural identity. What I found during my fieldwork was that traditional storytelling processed environmental changes as a way of maintaining a connection to a disappearing place. In this article I describe how environmental change is culturally manifest through tales of the supernatural, particularly spirit beings or ghosts. The types of IÑupiat stories and modes of telling them reveal people's uncertainty about the future. Examining how people perceive the loss of their homeland, I argue that IÑupiat storytelling both reveals and is a response to a changing physical and spiritual landscape.  相似文献   
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Abstract The upper Jurassic Nikoro greenstone complex of eastern Hokkaido suffered high-pressure intermediate type metamorphism. Characteristic minerals include lawsonite, aragonite, sodic pyroxene of the aegirinejadeite series, winchite. sodic amphibole of the glaucophane-riebeckite series, pumpellyite, epidote and actinolite.
High-pressure metamorphism of the Nikoro greenstone complex is related to subduction of the Kula plate toward the Palaeo-Okhotsk Land during Cretaceous time.  相似文献   
5.
The Susunai Complex of southeast Sakhalin represents a subduction-related accretionary complex of pelitic and basic rocks. Two stages of metamorphism are recognized: (1) a local, low- P / T  event characterized by Si-poor calcic amphiboles; (2) a regional, high- P / T  event characterized by pumpellyite, actinolite, epidote, sodic amphibole, sodic pyroxene, stilpnomelane and aragonite. The major mineral assemblages of the high- P / T  Susunai metabasites contain pumpellyite+epidote+actinolite+chlorite, epidote+actinolite+chlorite, epidote+Na-amphibole+Na-pyroxene+chlorite+haematite. The Na- amphibole is commonly magnesioriebeckite. The Na-pyroxene is jadeite-poor aegirine to aegirine-augite. Application of empirically and experimentally based thermobarometers suggests peak conditions of T  =250–300 °C, P= 4.7–6 kbar. Textural relationships in Susunai metabasite samples and a petrogenetic grid calculated for the Fe3+-rich basaltic system suggest that pressure and temperature increased during prograde metamorphism.  相似文献   
6.
The low‐grade metamorphosed Jurassic accretionary complex of the Northern Chichibu Belt, Hijikawa area, western Shikoku, is divided into two units, the Hijikawa and Kanogawa units, that are separated by an out‐of‐sequence thrust (OOST), the Ozu‐Kawabegawa Fault. The Kanogawa unit south of the Ozu‐Kawabegawa fault consists mainly of sandstone, shale, broken formation of alternating sandstone and shale, greenstone, chert, and pelitic melange, while the Hijikawa unit is characterized by a stack of subunits separated by small‐scale thrusts. The subunits are mainly made up of basic, pelitic and psammitic semischists, schistose pelitic melange, and chert. Petrological and mineralogical constraints suggest peak metamorphic conditions of 204–247 °C at 1–3 kbar in the Kanogawa unit, and 228–289 °C at 3–5.6 kbar in the Hijikawa unit. Quartz and quartz‐calcite veins are widely developed in the study area, especially in the Hijikawa unit. Regional variations in stable isotopic data show that the δ18Oquartz and δ18Ocalcite values in veins tend to increase towards the Ozu‐Kawabegawa Fault. The δ18Owhole rock values are remarkably high in some subunits close to OOSTs within the Hijikawa unit. Oxygen isotopic compositions from vein quartz indicate that a higher δ18O fluid migrated upward from depth along the Ozu‐Kawabegawa Fault within the accretionary prism during prehnite‐pumpellyite facies metamorphism. The fluid source is inferred to be pelitic rocks at higher temperatures and greater depths within the accretionary prism.  相似文献   
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