Tropical rubber plantation forest is the most important ecosystem in tropical China, and it plays an important and representative role in the study of solar radiation in tropical forest. It is necessary to study the radiation flux of rubber plantation forest because of the increasing questions about the ecological effects of the large-scale cultivation of rubber trees in tropical China. Solar radiation is the primary energy source for ecosystems, and the net radiation (NR) energy drives the ecosystem's life activities and energy flows. This study analyzed temporal variations and distributions of solar radiation and its components based on radiation fluxes observations on an iron tower of 50 m high in Hainan Island in 2010. The results showed that the diurnal variations in global solar radiation (DR), reflected radiation (UR) and NR all were represented by typical single-peak curves. Atmospheric inverse-radiation (DLR), forest long-wave radiation (ULR) and effective long-wave radiation (Ln) were represented by an undulating curve. Gross radiations, except Ln，in rainy season, were greater than those in dry season. Diurnal variation in the NR/DR ratio showed an inverted U-shaped curve while the Ln/DR and UR/DR ratios showed U-shaped curves. In addition, the relationship between the radiation fluxes was studied, too. And the annual mean reflectivity was 14.18%, the ratio of DLR/ULR 92.4% in 2010. Net radiation (NR) and global solar radiation (DR) was most closely related.
Transport is vital to regional development, which has impact not only on economy but also on society and politics. The level of regional transport consists of the interior connection and inter-regional accessibility, so the transport superiority can be quantified by multi-dimension system analysis. The system includes three dimensions: transport network density, influence degree of transport facilities and diffusion effect of the transport hubs. On the basis of mathematical evaluation model，this paper studies the spatial transport superiority in Guangdong Province, and some conclusions have been drawn. First, the transport superiority of the Pearl Delta is much higher than that of other areas in the province, where the three dimensions are all above the provincial average level. The transport superiority is higher on the east of the Pearl River mouth than on the west. Second, the spatial characteristic shows the transport superiority’s layer-loop structure. The superiority decreases gradually from the core (the Pearl River Delta) to the margin (the north mountain area), from the coast areas to the inland. Moreover, the study also reveals that there is a positive relation between transport superiority and economic development level. The transport superiority is proportionate to the economic development level that can be proved by the regression analysis with transport superiority degree and GDP per capita.
Coordinative urban-rural development has been identified to be the national strategy. Various efforts have been put into practices，and a series of achievements have been made by researchers. But still there are so many problems those need to be explored and solved. Taking Jiangbei District, a typical developed area in Chongqing City, as the study area, the authors make efforts to examine the measures put forward by government in the process of coordinating urban-rural development in Chongqing City. Those measures include the policies in economic development, social policy, and urban-rural plan, etc. Both positive and negative impacts of the measures on rural area are assessed, and a comprehensive model for the coordinative urban-rural development in Jiangbei District is constructed. The authors argue that at present the coordinative Urban-Rural development practice in Chongqing is of a government-dominant model, in which the market forces and public participation are relatively neglected.
In this paper，ESRE（Economy-Society- Resource-Environment）complex system theory is used to study the coordinated development of the Nanliujiang Basin. For that purpose a coordinated development degree evaluation index system is constructed. The traditional measurement model of regional development is optimized．The coordinated development degrees of economy，society，resources and environment for upstream（Yulin）, midstream（Bobai）, and downstream（Beihai）subsystems of the Nanliujiang Basin are calculated. The result shows that in recent years the coordination level of the ESRE complex system of the Nanliujiang Basin basically remains stable，the upstream region and midstream region are in good state of coordination，and the downstream region achieves high quality state of coordination．With the accelerating process of industrialization in the basin，the pressure on ecological environment is also increasing．
