Search Results (3)

Examining land use transition is a new way of building on the comprehensive research on Land Use/Cover Change (LUCC). Research on transition law and characteristics is important for improving the theory of land use transition and the practice of land resource management, and for being able to provide a basis and reference for promoting socio-economic transformation. Based on the relevant statistical data concerning cultivated land use in the Huaibei area of the Jiangsu Province from 1995 to 2020, and by understanding the county as a unit to be measured, this paper constructed a multi-dimensional (economic–social–ecological) functional index system of recessive morphology, analyzed the spatio-temporal pattern of the transition of cultivated land use, identified transition point mutations, and established the transition mode by adopting multi-dimensional time series point mutation detection and the piecewise linear regression method. The findings suggest that the index of recessive cultivated land use morphology in the Huaibei region of the Jiangsu Province presents a trend of “slow decline to significant growth to stable growth”. Moreover, the index presented evolutionary characteristics such as “high in the middle and east while low in the west”, as well as “the relatively balanced distribution between counties”, thus indicating that the degree of transition deepened, it showed a homogeneous development trend, and the transition process presented obvious “ladder” stage characteristics; therefore, the authors suggest making scientific use of cultivated land resources, in accordance with local conditions, in order to make the land use transition of cultivated land efficient, green, and sustainable. Full article

Coastal areas are vulnerable to floods caused by rainstorms and typhoons. It is necessary to ascertain the risk of floods caused by both of these extreme weather events. A conceptual risk model is proposed to evaluate the rainstorm risk, typhoon surge risk, and the compound risk in the coastal areas of Jiangsu Province during the period of 1960–2012. The results of the model show that the typhoon surge risk in the study region is greater than the rainstorm risk. Three Archimedean copulas were used to fit the joint probability distributions of the compound events. The Frank copula and the Gumbel copula proved to be the best-fitting joint distribution function for the Huaibei plain district and the Lixiahe district, respectively. The probability of the extreme compound events not happening is less than 90% in the study region. This means that the flood risk is mainly subject to the encounter of a low-level rainstorm and a low-level typhoon surge. The study shows that the northern region of Jiangsu Province is more vulnerable to the compound risk, and that we should pay more attention to the floods caused by the compound events of rainstorm and typhoon surge. Full article

Reference evapotranspiration (ET_ref) is a key parameter of hydro-meteorological studies as well as water resource planning. In this study, we adopted the Penman–Monteith FAO 56 model to estimate ET_ref and through the differential equation and detrending method to determine sensitivities and the contributions of four meteorological parameters to ET_ref based on daily weather data from 60 stations of Jiangsu province during 1961–2015. Results reveal that ET_ref and its trends in the three sub-regions of the Jiangsu province had a significant spatial heterogeneity. A significant decreasing tendency of ET_ref (p < 0.001) was observed in the Huaibei region, while a slightly increasing tendency was identified in the Jianghuai and Sunan regions. These changes of ET_ref were caused by a significant increasing trend in air temperature (TA) and significant decreasing trends in wind speed (WS), sunshine duration (SD) as well as a non-significant change trend in actual vapor pressure (VP). However, the VP was the meteorological parameter to which ET_ref was most sensitive, whereas ET_ref was more sensitive to TA and SD in the summer but less so in the winter; the least sensitive factor, WS, had the opposite trend. Across the whole region, WS contributed most to ET_ref, followed by SD, while the positive contribution of TA to ET_ref could not offset the negative contributions of WS and SD. Although the effect of VP on changes in ET_ref is small, it could not be ignored, especially in the winter. The reverse relationship between increasing TA and decreasing ET_ref, namely the “evaporation paradox,” occurred in Jiangsu province. Thus, the outcomes of this study will contribute to thorough insight into the response to changes in ET_ref to the provincial water planning and management in eastern China. Full article