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Sri Lanka being an agrarian country, the role of water is important for agricultural production. In Sri Lanka, various tank cascade systems, earthen dams and distribution canals have been accepted as few of the most complex ancient traditional water systems of the world. Rainfall, surface water, groundwater and runoff are linked with each other, they have close interactions to land cover classes such as forests and agriculture. The monitoring of vegetation conditions can show subsurface manifestations of groundwater. In this study, an effort to understand the role of traditional water reservoirs and groundwater recharge was made using remote sensing techniques. We have analyzed various vegetation indices such as Normalized Difference Vegetation Index (NDVI), Enhanced Vegetation Index (EVI-2), Soil-Adjusted Vegetation Index (SAVI), tasselled cap transformation analysis (TCA brightness, greenness and wetness) and their relations with the existence of soil, vegetation and water. Result shows that EVI, SAVI, and TCA-based Greenness Index indicates good relationship with the vegetation conditions as compared to other indices. Therefore, these indices could play a crucial role in depicting the interaction between soil, vegetation, and water. However, multi-temporal observations can provide significant results about these interactions more accurately.  相似文献   
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Here we propose a method to quantitatively assess and examine Global No Net Loss (GNNL) of forest biodiversity on a global scale. The method produces a GNNL index of existing forest and enables future predictions of forest loss under different assumptions. The method tests the feasibility of the GNNL index and enables discussion of policy for future global scale sustainable forest management up to 2050. The GNNL index was estimated from an equation including forest areas per country per forest type (primary forest, secondary forest and plantation forest), diversity of forest ecosystem, and species density. Estimates derived from historical data revealed an approximate 7% reduction in GNNL index between 1990 and 2005. Predictions of the GNNL index until 2050 emphasize the importance of regenerating large portions of forests felled for agricultural land (or other uses) with secondary forests.  相似文献   
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Agroforestry in the Western Ghats (WG) of peninsular India and satoyama in rural Japan are traditional land-use systems with similar evolutionary trajectories. Some of their relevance was lost by the middle of the twentieth century, when modern agricultural technologies and urbanisation engineered shifts in emphasis towards maximising crop production. There has been, however, a resurgence of interest in traditional land-use systems recently, in view of their ability to provide ecosystem services. Both agroforestry and satoyama are thought to be harbingers of biological diversity and have the potential to serve as “carbon forests.” Carbon (C) stock estimates of the sampled homegardens in WG ranged from 16 to 36 Mg ha−1. Satoyama woodlands owing to variations in tree stocking and management conditions indicated widely varying C stocks (2–279 Mg ha−1). Agroforestry and satoyama also differ in nature, complexity, and objectives. While agroforestry involves key productive and protective functions, and adopts ‘intensive management’, the satoyama woodlands are extensively managed; understorey production is seldom a consideration. Differences in canopy architecture (multi-tiered structure of agroforestry vs. the more or less unitary canopy of satoayama) and land ownership pattern (privately owned/managed agroforestry holdings vs. community or local government or privately owned and mostly abandoned satoyamas) pose other challenges in the transfer and application of knowledge gained in one system to the other. Nonetheless, lessons learnt from satoyama conservation may be suitable for common pool resource management elsewhere in Asia, and aspects relating to understorey production in agroforestry may be relevant for satoyama under certain scenarios.  相似文献   
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Journal of Material Cycles and Waste Management - In this feasibility study, the anaerobic co-digestion of different organic wastes obtained from a dairy farming area in Hokkaido prefecture, Japan...  相似文献   
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Male butterflies compete over mating territories via aerial interactions. It has often been suggested that flight performance, and thus flight-related traits, would play an important role in butterflies’ contest resolution; however, most studies have not demonstrated a clear relationship between these traits and territory ownership in butterflies. Males of the satyrine butterfly Lethe diana compete over territories via linear chases, a behavior that is uncommon among butterflies: rather, contests of most butterfly species consist of circling flights. In the present study, some morphological and physiological traits of L. diana were compared between territory owners and intruders to search for traits correlated with resource holding power (RHP). Territory owners had higher flight-muscle ratio (FMR) and were heavier than intruders, indicating that flight performance plays a key role in their contest resolution. Contest duration was not affected by the owners’ FMR or body mass, and thus I obtained no evidence supporting the hypothesis that contestants assess their relative RHP before making a decision to retreat. I speculate that the fact that these traits had an effect on territorial status in L. diana was a result of the characteristics of the contest behavior of this butterfly. During their contests, males L. diana fly faster in their linear flights than males of most other butterflies, which engage in slower circling flights. Therefore, males of L. diana probably need higher flight performance capabilities in order to win their contests.  相似文献   
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The Japanese rural coastal areas are inherently vulnerable to typhoons and tsunamis. Their vulnerability has been further increasing recently, in part due to social factors such as the aging of society and depopulation. Following the Kobe earthquake of 1995, the Japanese government has promoted the Voluntary Disaster Preparedness Organization (VDPO) to build communities that are more sustainable and resilient to natural disasters. However, studies indicate that some VDPO activity has stagnated. The present study focuses on a rural coastal area in Japan and examines whether VDPO impacts residents’ awareness of disaster preparedness and also examines ties among the community. The study relies on a questionnaire survey. It reveals that VDPO contributes to improving both awareness of disaster preparedness and ties in the community.  相似文献   
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