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Modelling Skylarks (Alauda arvensis) to Predict Impacts of Changes in Land Management and Policy: Development and Testing of an Agent-Based Model  [PDF]
Christopher J. Topping, Peter Oddersk?r, Johnny Kahlert
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0065803
Abstract: Agent-based simulation models provide a viable approach for developing applied models of species and systems for predictive management. However, there has been some reluctance to use these models for policy applications due to complexity and the need for improved testing and communication of the models. We present the development and testing of a comprehensive model for Skylark (Alauda arvensis) in Danish agricultural landscapes. The model is part of the ALMaSS system, which considers not only individual skylarks, but also the detailed dynamic environment from which they obtain the information necessary to simulate their behaviour. Population responses emerge from individuals interacting with each other and the environment. Model development and testing was carried out using pattern-oriented modelling. The testing procedure was based on the model's ability to represent detailed real world patterns of distribution and density, reproductive performance and seasonal changes in territory numbers. Data to support this was collected over a 13-year period and comprised detailed field observations of breeding birds and intensive surveys. The model was able to recreate the real world data patterns accurately; it was also able to simultaneously fit a number of other secondary system properties which were not formally a part of the testing procedure. The correspondence of model output to real world data and sensitivity analysis are presented and discussed, and the model's description is provided in ODdox format (a formal description inter-linked to the program code). Detailed and stringent tests for model performance were carried out, and standardised model description and open access to the source code were provided to open development of the skylark model to others. Over and above documenting the utility of the model, this open process is essential to engender the user trust and ensure continued development of these comprehensive systems for applied purposes.
The dynamic changes of ecosystem spatial pattern and structure in the Three-River Headwaters region in Qinghai Province during recent 30 years
30年来青海三江源生态系统格局和空间结构动态变化

XU Xin-liang,LIU Ji-yuan,SHAO Quan-qin,FAN Jiang-wen,
徐新良
,刘纪远,邵全琴,樊江文

地理研究 , 2008,
Abstract: Supported by MSS images in the mid and late 1970s,TM images in the early 1990s and TM/ETM images in 2004,the spatial distribution data set of ecosystem types was acquired through analysis and distinguishment,then the dynamic changes of spatial pattern and structure of ecosystems in the Three-River Headwaters region were analyzed since the 1970s.The results showed that alpine grassland occupied the largest area in the Three-River Headwaters region,and the area of alpine grassland occupied 64.68% of the total land area and 99.58% of the total grassland area.Wetland,glacier and mountain permanent snow-cover were characteristic ecosystems in the Three-River Headwaters region,with marsh area occupying 26.09% of the total area of water and wetland ecosystem,and glacier and mountain permanent snow-cover area 9.02% of the total area of water and wetland ecosystem.As the characteristic ecosystems in the Three-River Headwaters region,wetland,glacier and mountain permanent snow-cover played important roles in providing stable water resource.During recent 30 years,the changes of ecosystem spatial pattern in the Three-River Headwaters region have been stable and rather slow,with an annual changing rate of farmland,forest,grassland,water and wetland,and hungriness ecosystem being less than 0.5% respectively,the least but stable in the Yangtze and Yellow river basins,even the whole country.The changes of grassland,water and wetland ecosystem have occupied a dominant position in the Three-River Headwaters region since the mid and late 1970s.The changes of grassland mainly occurred in the central and eastern parts of the region,dominated by reclamation of grassland and conversion of grassland into unused land such as bare land,sandy and salt land.And the changes of water and wetland ecosystem mainly occurred in the vast western and northern parts of the region,represented by conversion of water body into beach land and conversion of wetland into grassland.
Reasoning Principles for Negotiating Agent  [cached]
Mu-kun Cao,Yu-qiang Feng
Journal of Software , 2008, DOI: 10.4304/jsw.3.9.12-19
Abstract: Automated negotiation is an important applying field of agent theory and technology. For the current agent theoretical models have some troubles in explaining the agent's negotiation behaviors, this paper defines utility as costs and incomes coming from the transformation of the possible negotiation states. This lead to a semantic model fitting the agent's automated negotiation. Then, on the basis of the classical Belief-Desire-Intention model, a logic named BDI-U is completely proposed, which can explain the principles of the negotiating agent’s reasoning process. Therefore, the model can support further design and development of negotiating agent. The work performs five steps: designing formal language, designing semantic model, explaining semantics, proposing and explaining system axioms, and the axioms’ validity proof.
Glacier Changes in the Heihe River Basin over the Past 50 Years in the Context of Climate Change
气候变化背景下近50年来黑河流域冰川资源变化特征分析

WANG Puyu,LI Zhongqin,GAO Wenyu,YAN Donghai,BAI Jinzhong,LI Kaiming,WANG Lin,
王璞玉
,李忠勤,高闻宇,颜东海,白金中,李开明,王林

资源科学 , 2011,
Abstract: The Heihe River basin, located in the middle part of the Qilian Mountains, is the second largest inland river basin across the arid area of northwestern China, east to the headwaters of Xidahe of the Shiyang River, west bounded by the Heishan and Shulehe, and the upper reaches almost across the Hexi Corridor. Glaciers, acting as a huge alpine reservoir that regulates annual runoff, are considered a reliable water source for oasis, benefiting the sustainable development of the environment, industry, and agriculture in this region. During the past decades, glaciers in the Heihe River basin have been experienced rapid shrinking due primarily to climate change. Impacts of the glaciers shrinkage on water resources have drawn much attention. Using the image interpretation method provided by World Glacier Monitoring Service (WGMS), historical data were retrieved for comparison with remote sensing images in order to reveal changes in glaciers in the Heihe River basin during the past 50 years. To compare recent changes in the glacier areas, 5 scenes of Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) images with spatial resolution of 15 m for visible and near-infrared bands acquired from June to September in 2003 and 24 topographic maps (1:50 000) derived from aerial photographs acquired during 1956-1978 (18 in 1956, 1 in 1957, 3 in 1966, and 2 in 1978) by the Chinese military geodetic service were jointly used and comprehensively analyzed. It is found that from the 1950s/1970s to 2003, the total area of the investigated glaciers (335) was reduced by 29.6%, with a mean reduction of 0.10 km2 for the individual glacier. The glaciers retreated by 258 m at a rate of 31.0%. The glacier changes exhibited obvious spatial differences, indicating that the reduction rate of glaciers to the west of the mainstream of the Heihe was larger than the east. In addition, rapidly rising air temperature is likely the major factor causing the shrinkage of the glaciers in the Heihe River basin. Compared with other glaciers in western China, glaciers in the Heihe River basin appeared to be decreasing more rapidly. Moreover, the glacier changes showed remarkable differences in the eastern, middle and western Qilian Mountains mainly due to climatic conditions and glacier sizes.
Land use and climate change impacts on the hydrology of the upper Mara River Basin, Kenya: results of a modeling study to support better resource management
L. M. Mango, A. M. Melesse, M. E. McClain, D. Gann,S. G. Setegn
Hydrology and Earth System Sciences (HESS) & Discussions (HESSD) , 2011,
Abstract: Some of the most valued natural and cultural landscapes on Earth lie in river basins that are poorly gauged and have incomplete historical climate and runoff records. The Mara River Basin of East Africa is such a basin. It hosts the internationally renowned Mara-Serengeti landscape as well as a rich mixture of indigenous cultures. The Mara River is the sole source of surface water to the landscape during the dry season and periods of drought. During recent years, the flow of the Mara River has become increasingly erratic, especially in the upper reaches, and resource managers are hampered by a lack of understanding of the relative influence of different sources of flow alteration. Uncertainties about the impacts of future climate change compound the challenges. We applied the Soil Water Assessment Tool (SWAT) to investigate the response of the headwater hydrology of the Mara River to scenarios of continued land use change and projected climate change. Under the data-scarce conditions of the basin, model performance was improved using satellite-based estimated rainfall data, which may also improve the usefulness of runoff models in other parts of East Africa. The results of the analysis indicate that any further conversion of forests to agriculture and grassland in the basin headwaters is likely to reduce dry season flows and increase peak flows, leading to greater water scarcity at critical times of the year and exacerbating erosion on hillslopes. Most climate change projections for the region call for modest and seasonally variable increases in precipitation (5–10 %) accompanied by increases in temperature (2.5–3.5 °C). Simulated runoff responses to climate change scenarios were non-linear and suggest the basin is highly vulnerable under low ( 3 %) and high (+25 %) extremes of projected precipitation changes, but under median projections (+7 %) there is little impact on annual water yields or mean discharge. Modest increases in precipitation are partitioned largely to increased evapotranspiration. Overall, model results support the existing efforts of Mara water resource managers to protect headwater forests and indicate that additional emphasis should be placed on improving land management practices that enhance infiltration and aquifer recharge as part of a wider program of climate change adaptation.
Fluvial sediment inputs to upland gravel bed rivers draining forested catchments: potential ecological impacts  [PDF]
S. D. Marks,G. P. Rutt
Hydrology and Earth System Sciences (HESS) & Discussions (HESSD) , 1997,
Abstract: As identified by the detailed long-term monitoring networks at Plynlimon, increased sediment supply to upland fluvial systems is often associated with forestry land-use and practice. Literature is reviewed, in the light of recent results from Plynlimon sediment studies, to enable identification of the potential ecological impacts of fluvial particulate inputs to upland gravel bed rivers draining forested catchments similar to the headwaters of the River Severn. Both sediment transport and deposition can have significant impacts upon aquatic vertebrates, invertebrates and plants.
Analyses on the Changes of Grazing Capacity in the Three-River Headwaters Region of China under Various Climate Change Scenarios  [PDF]
Rongrong Zhang,Zhaohua Li,Yongwei Yuan,Zhihui Li,Fang Yin
Advances in Meteorology , 2013, DOI: 10.1155/2013/951261
Abstract: On the livestock production in the Three-River Headwaters region (TRHR) in the macrocontext of climatic change, this study analyzed the possible changing trends of the net primary productivity (NPP) of local grasslands under four RCPs scenarios (i.e., RCP2.6, RCP4.5, RCP6.0, and RCP8.5) during 2010–2030 with the model estimation, and the grass yield and theoretical grazing capacity under each scenario were further qualitatively and quantitatively analyzed. The results indicate that the grassland productivity in the TRHR will be unstable under all the four scenarios. The grassland productivity will be greatly influenced by the fluctuations of precipitation and the temperature fluctuations will also play an important role during some periods. The local grassland productivity will decrease to some degree during 2010–2020 and then will fluctuate and increase slowly during 2020–2030.The theoretical grazing capacity was analyzed in this study and calculated on the basis of the grass yield. The result indicates that the theoretical grazing capacity ranges from 4 million sheep to 5 million sheep under the four scenarios and it can provide quantitative information reference for decision making on how to determine the reasonable grazing capacity, promote the sustainable development of grasslands, and so forth. 1. Introduction The net primary productivity (NPP) of vegetation reflects the productivity of the vegetation under the natural conditions [1]. The climatic change is one of the key driving forces of the interannual change of NPP of vegetation [2]. The climate is undergoing the change which is mainly characterized by the global warming. The land surface temperature has increased significantly since the 1980s, especially in the northern region of China [3–6]. The grassland is one of the most important land use types in China, which has essential functions in the development of the animal husbandry [7]. The grassland is greatly influenced by the climatic change, and the spatiotemporal change of NPP of grasslands and the influencing mechanism of the climatic change on it have been one of the research focuses at home and abroad [8–11]. The Three-River Headwaters region (TRHR) is the headstream of the Yellow River, Yangtze River, and Lancang River, which is one of the most ecologically sensitive areas in China. Besides, it is also the largest animal husbandry production base in Qinghai Province, with about 21.3 thousand?km2 of native pasture and native grassland. Many researchers have analyzed the change of NPP in this area from different perspectives [12–16] and
The complex nonlinear systems with fractal as well as chaotic dynamics of annual runoff processes in the three headwaters of the Tarim River

XU Jianhua,CHEN Yaning,LI Weihong,JI Minhe,DONG Shan,

地理学报 , 2009,
Abstract: This paper attempted to identify fractal and chaotic characteristics of the annual runoff processes in headwaters of the Tarim River. Methods of fractal analyses were used to explore several aspects of the temporal changes from 1957 to 2002. The main findings are as follows: (1) The annual runoff processes of the three headwaters of the Tarim River are complex nonlinear systems with fractal as well as chaotic dynamics. (2) The correlation dimensions of attractor derived from the time series of the annual runoff for the Hotan, Yarkand and Aksu rivers are all greater than 3.0 and non-integral, implying that all three rivers are chaotic dynamical systems that are sensitive to initial conditions, and the dynamic modeling of their annual runoff process requires at least four independent variables. (3) The time series of annual runoff in each river presents a long-term correlation characteristic. The Hurst exponent for the period of 1989 to 2002 suggests that we may expect to see an increasing trend in the annual runoff of the Aksu and Yarkand rivers in the years after 2002, but a decreasing tendency for the Hotan River in the same period.
Large dams and changes in an agrarian society: Gendering the impacts of Damodar Valley Corporation in eastern India
Kuntala Lahiri-Dutt
Water Alternatives , 2012,
Abstract: This paper traces the gendered changes in agrarian livelihoods in the lower Damodar valley of eastern India and connects these changes to the large dam project of the Damodar Valley Corporation (DVC). The DVC, established in 1948, was one of the earliest dam projects in India. Although it was not fully completed, the DVC project has initiated unforeseen changes in the farming economy. The floods for which the Damodar river was notorious were not fully controlled, and the suffering of people living in the lower reaches of the valley never really diminished. This paper gives a brief description of the river and its history of water management practices and the roles of women and men in these practices. It traces the resultant impacts on gender roles, and outlines the new kinds of water management that emerged in response to the DVC’s failure to provide irrigation water when demanded. More specifically, the paper explores the changes in floods, changes in the farming economy, and the impacts of temporary sand dams or boro bandhs on the livelihoods of women and men from farming families in the Lower Damodar Valley. It observes that even over a longer temporal scale, the changes unleashed by large water control projects have significant and gendered impacts on agrarian societies.
Impacts of land use changes on groundwater resources in the Heihe River Basin

WANG Genxu,YANG Lingyuan,CHEN Ling,Jumpei Kubota,

地理学报 , 2005,
Abstract: Land use and land cover changes have a great impact on the regional hydrological process. Based on three periods of remote sensing data from the 1960s and the long-term observed data of groundwater from the 1980s, the impacts of land use changes on the groundwater system in the middle reach of Heihe River Basin in recent three decades are analyzed by the perspective of groundwater recharge and discharge system. The results indicate that with the different intensities of land use changes, the impacts on the groundwater recharge were 2.602×108 m3/a in the former 15 years (1969-1985) and 0.218×108 m3/a in the latter 15 years (1986-2000), and the impacts on the groundwater discharge were 2.035×108 m3/a and 4.91×108 m3/a respectively. When the groundwater exploitation was in a reasonable range less than 3.0×108 m3/a, the land use changes could control the changes of regional groundwater resources. Influenced by the land use changes and the large-scale exploitation in the recent decade, the groundwater resources present apparently regional differences in Zhangye region. Realizing the impact of land use changes on groundwater system and the characteristics of spatial-temporal variations of regional groundwater resources would be very important for reasonably utilizing and managing water and soil resources.
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