Simulating land use for protecting food crop areas in northeast Thailand using GIS and Dyna-CLUE     

Sakayarote  Kanda  Shrestha  Rajendra P. 《地理学报(英文版)》2019,29(5):803-817

Journal of Geographical Sciences - Land use in the northeast region of Thailand has changed dramatically in the past two decades. These changes are mainly due to the government policies, which...  相似文献   

Ecology of Pinnidae (Mollusca: Bivalvia) from the Gulf of Thailand     

PRINTRAKOON Cheewarat  ROOPNARINE Peter D  YEEMIN Thamasak 《海洋学报(英文版)》2019,38(2):52-69

The ecology of the family Pinnidae was studied by sampling three pinnid species from 36 sampling sites across four different microhabitats in the Gulf of Thailand. The species spatial distributions were mostly uniform, with some populations having random distributions. Species abundances differed between sandy and coral habitats according to non-metric multi-dimension scaling analyses. Although the Gulf of Thailand is a relatively small geographic area, habitats are varied enough to provide variable shell densities. Small islands are important distribution areas, and coral reefs provide both direct and indirect shelter which support high abundances, densities and increased shell size. The highest density was recorded in sand beds within coral reefs. Low density and small shell size in sand beaches might be related to high mortality in shallow water or to adaptations for survival in shallow waters. A clear correlation between sediment composition and species abundance was found in Pinna atropurpurea; abundance increased with the sand content of the sediment. For P. deltodes, abundance increased as the rock fraction of the sediment increased. These results suggest that adaptations in Pinnidae, such as shell size, shell morphology, and the exposure of the shell above the sediment-water interface, are responses for survival in different habitats.  相似文献   

南海西南部巽他陆架底层冷水及其季节变化分析     

周文正  于非  南峰  刁新源  李昂 《海洋与湖沼》2015,46(1):1-8

本文利用历史水文观测数据研究了南海西南部巽他陆架水团特征,结果表明:(1)巽他陆架纳土纳群岛周围底层存在着低温高盐的冷水,该冷水沿地形爬升分为两支,一支可延伸至泰国湾,另一支伸向卡里马塔海峡;(2)巽他陆架底层冷水有明显的季节变化,该底层冷水在春季开始形成,夏季达到最强,秋季开始衰退,最后在冬季完全消失;(3)巽他陆架底层冷水来源于南海次表层水的涌升。夏季西南季风使陆架表层水向南海流动,有利于南海次表层低温高盐水沿地形向陆架爬升,此时底层冷水与表层水温差超过8°C。冬季东北季风,使南海表层水向陆架流动,海水在陆架堆积,从而阻止了南海次表层低温高盐水的爬升。  相似文献   

Protected areas in mainland Southeast Asia, 1973–2005: Continuing trends     

Steve Déry  Romain Vanhooren 《Singapore journal of tropical geography》2011,32(2):185-202

Since the 1970s, protected area networks in mainland Southeast Asian countries have developed significantly to occupy 4–25 per cent of their respective national areas, located mostly in the mountainous domains of ethnic minority peoples. Through this process, regions that were only nominally part of national geobodies until the 1950s have become more territorially integrated. The complexity of the characteristics and geographical impacts of this territorialisation have yet to be grasped. As a step in this direction, we briefly outline a multilevel systems approach that usefully contextualizes these issues together with a historical and cartographical assessment of the evolution of protected area networks for Burma, Thailand, Laos, Cambodia and Vietnam. Our main findings are intertwined. On the one hand, protected areas represent a new tool of state intervention in mountainous areas, clearly in keeping with past, notably colonial, actions. On the other hand, this evolution in state territorialisation and attendant power relations have disrupted, far more deeply than previous actions, the pre‐1970s sociogeographical organization in mountainous areas, where most of the region's residual forests remain.  相似文献   

Aquaculture and the poor-Is the culture of high-value fish a viable livelihood option for the poor?     

Natasja Sheriff  David C. Little  Kwanta Tantikamton 《Marine Policy》2008,32(6):1094-1102

This study evaluates the role of high-value fish culture in the livelihoods of coastal households in southern Thailand. The study shows that grouper culture, promoted as an alternative to destructive fishing practices, can make a substantial contribution to household incomes. However, fishing and aquaculture play contrasting roles in the livelihoods of coastal fishers and should be considered as complementary rather than alternative occupations. The study found that poorer households can benefit significantly from raising grouper in cages if certain conditions are met, including access to credit and the substitution of financial for natural capital.  相似文献   

Study on the geochemical characteristics of ocean-ridge and oceanic-island volcanic rocks in the Nan-Uttaradit zone,northern Thailand     

Chong pom Chong lakmani 《中国地球化学学报》2010,29(2):175-181

Field investigations and laboratory integrated research as indicated that ophiolite mélange in the Nan-Uttaradit zone, northern Thailand, consists of fragments of tectonites such as metamorphic peridotite (extremely silicified serpentinite), cumulates (pyroxenolite, gabbro, and gabbro-diorite), ocean-ridge basalt, oceanic-island ba-salt and radiolarian silicalite, and it was formed during D3-P. The rock series, rock types and petrogeochemical characteristics of metamorphic tholeiites in the Nan area of the Nan-Uttaradit zone are similar to those of ocean-ridge basalts (C1) in China's Ailaoshan zone. As for the Hawaiites in the Nan area of the Nan-Uttaradit zone, their major elements, REEs and trace elements are similar to those of oceanic-island basalts in China's Jinshanjiang zone (P11). In the Uttaradit area of this zone the metamorphic alkaline basalts show transitional petrogeochemical characteristics between ocean-ridge basalts and oceanic-island basalts, which were still formed in oceanic-island environments. The above-described basalts are all oceanic volcanic rocks and they are the most important part of the Paleo-Tethys oceanic crust in the Nan-Uttaradit zone.  相似文献   

东构造节的伸展和折返: 泰国北部裂谷的重力信号     

John MILSOM 《地球学报》2012,33(S1):41-42

Although many of its details have been criticised, the indenter model of India-Asia collision (Fig 1) is still widely accepted as providing a workable first-order explanation for the structural development of the eastern syntaxis and the initiation of the major NW-SE faults that segment the mainland of Southeast Asia. Arguments have largely concerned the extent to which the arrival of the continental crust of greater India has been accommodated by thickening beneath the Tibetan Plateau or by extrusion of blocks into Southeast Asia. Second-order structures relevant to such questions include elevated plateaus, metamorphic core complexes and the networks of rift basins with broadly N-S trends. In northern Thailand, one such rift network has been responsible for the development of a characteristic basin-and-range morphology.  相似文献   

泰国难府-程逸缝合带中灰岩块的 虫筳 类生物地层学     

Thasinee CHAROENTITIRAT  Sarawute CHANTRAPRASERT 《地球学报》2012,33(S1):74-74

The study area, Nan Province, northern Thailand is geotectonically situated within the Nan-Uttaradit Suture, the once back-arc basin between the Sukhothai Zone and Indochina Block. Permian Fusulinacean fauna from limestone blocks within the suture has been investigated and the Nan area has been mapped in detail. These may provide the useful information for understanding the faunal assemblage and overall ge-ometry of stratigraphic successions in the basin. The strata were intensely folded and thrust. Scattered Per-mian limestones found in Nan area are blocks within shale interbedded with tuffaceous rock. The contact between this unit and the adjacent units, the strongly foliated shale and tuffaceous sedimentary strata that are mildly metamorphosed and giving phyllitic tex-tures, has been interpreted as a west-dipping normal fault, namely the Pha Sing Fault. This fault runs par-allel to the Highway no.1080 (Nan-Tha Wang Pha). Middle and early Late Permian fusulinacean fauna found in the Nan area contains Neoschwagerina, Pseudodoliolina, Colania, Lepidolina, and Colaniella. Additionally, late Early Permian fusulinacean and Middle Triassic radiolarian fauna have been reported in this area (e.g., Fontaine, 2002; Saesaengseerung et al. 2008). These paleontological data show the existence of Nan Back-arc Basin during late Early Permian (Artin-skian) to Middle Triassic. Moreover, the similarity of fusulinacean assemblage yielding Permian limestone blocks of the Nan Back-arc Basin and the ones of the Indochina Block has been interpreted that the Permian limestone blocks in the Nan Back-arc Basin were part of the continental shelf within the Indochina Block.  相似文献   

Regionalisation of hydrological responses under land-use change and variable data quality     

S. Visessri  N. McIntyre 《水文科学杂志》2013,58(2):302-320

ABSTRACT

Estimating river flows at ungauged sites is generally recognised as an important area of research. In countries or regions with rapid land development and sparse hydrological gauging networks, three particular challenges may arise—data scarcity, data quality, and hydrological non-stationarity. Using data from 44 gauged sub-catchments of the upper Ping catchment in northern Thailand from the period 1995–2006, three relevant flow response indices (runoff coefficient, base flow index and seasonal elasticity of flow) were regionalised by regression against available catchment properties. The runoff coefficient was the most successfully regionalised, followed by base flow index and lastly the seasonal elasticity. The non-stationarity (represented by the differences between two 6-year sub-periods) was significant both in the flow response indices and in land use indices; however relationships between the two sets of indices were weak. The regression equations derived from regionalisation were not helpful in predicting the non-stationarity in the flow indices except somewhat for the runoff coefficient. A partly subjective data quality scoring system was devised, and showed the clear influence of rainfall and flow data quality on regionalisation uncertainty. Recommendations towards improving data support for hydrological regionalisation in Thailand include more relevant soils databases, improved records of abstractions and investment in the gauge network. Widening of the regionalisation beyond the upper Ping and renewed efforts at using remotely sensed rainfall data are other possible ways forward.