Land use change (LUC) in trans-boundary watersheds is of great importance to environmental assessment. The Aksu River is the largest trans-boundary river crossing Kyrgyzstan and China, but there was little information on the LUC of the watershed. We quantitatively investigated the processes and trends of its LUC by using analytic models based on the land use data derived from the remote sensing images and topographic maps. The LUC was in the quasi-balanced status with a slight difference between the loss and the gain of the area for most land use types during the period of 1960-1990, whereas transferred to the unbalanced status with significant difference between the loss and gain of the area during the period of 1990-2008. At the same time, land conversion direction changed from two-way transition to one-way transition for the most land use types. The integrated rate of net change of land use during the period of 1990-2008 is 2.1 times of that during the period of 1960-1990. Information on the processes and trends of LUC is valuable for better understanding the environmental changes across the whole trans-boundary watershed, and helpful to decision-making management for Kyrgyzstan and China.

Owing to global climatic changes and human activities, the lakes have changed dramatically in the Junggar Basin of Xinjiang in recent 50 years. Based on the remote sensing images from Beijing Satellite No.1 in 2006 together with the measured topographical data in 1999 and other data since the 1950s, this paper analyzes mainly the features of landforms around the Manas Lake and the changes of feeding sources of the lake. The results are as follows: (1) Tectonic movement brought about the fundamental geomorphological basis for lacustrine evolution, and the Manas Lake is one of small lakes broken up from the Old Manas Lake due to tectonic movement and drought climate; the Manas Lake had existed before the Manas River flowed into it in 1915. The geomorphologic evidences for evolution of the Manas Lake include: (a) Diluvial fans and old channels at the north of the lake indicate that the rivers originating from the north mountains of the Junggar Basin had fed the Old Manas Lake and now still feed the lake as seasonal rivers; (b) The Old Manas Lake was fed by many rivers originating from the mountains, except for the Manas River, from the evidence of small lakes around the Manas Lake, old channels, alluvial fans, etc.; (c) The elevations of the alluvial and diluvial fans are near to the 280 m a.s.l. and all of the small lakes and lacustrine plains are within the range of the 280 m a.s.l., which may prove that the elevation of the Old Manas Lake was about 280 m a.s.l.; (d) Core analysis of the Manas Lake area also indicates that the Manas Lake has existed since Late Pleistocene epoch. (2) Analysis on the feeding relations between the lakes and the lacustrine evolution shows that human activities are one of main driving forces of the lacustrine evolution in recent 50 years, and it is the precondition of restoring and maintaining the lacutrine wetlands in the study area to satisfy the feeding of the Baiyang and Manas rivers to the Manas Lake.

In order to investigate the spatio-temporal variability of soil water content to rainfall under Caragana microphylla shrub in Horqin Sandy Land, a plot of 25 m × 25 m, where there were 6 shrub canopies of C. microphylla, was sited for measuring soil water content at two soil layers of 0-20 cm (top layer) and 20-40 cm (lower layer). Soil water content was measured on the 1st, 5th, 10th and 15th day after a 42 mm rainfall in Naiman of Inner Mongolia. The results showed that soil water contents at both layers under C. microphylla shrub were gradually decreased after the rain. Soil water content at the top layer outside the shrub canopy was higher than that inside the shrub canopy within 5 days, and became similar inside and outside the shrub canopy on the 10th day after the 42 mm rainfall, and it was lower outside than that inside the shrub canopy on the 15th day. The soil water content at lower layer in the area without shrubs was higher than that under shrub canopy all along. All the measured values of soil water content can be fitted to a variogram model. There was significant autocorrelation of the values of soil water content between top layer and lower layer, except for the fourth measured values of soil water content at top layer. The range and spatial dependence of soil water content at top layer were lower than that at lower layer.

As one of the most important biological factors that maintain the stability of the largest fixed and semi-fixed desert in China, the Gurbantunggut Desert, the biological soil crusts (BSCs) develop well and play critical ecological roles in the desert ecosystem. In this paper, we briefly summarize our research findings since 2002 including species composition, distribution pattern and ecological functions of BSCs in the desert. Our results indicate abundant species diversity of BSCs in the Gurbantunggut Desert in comparison to other deserts in China. At the scales of sand dune or whole desert, the distribution patterns of BSCs are location-specific. The existence of BSCs in this desert could: (1) accelerate the formation of desert soil and the weathering of minerals; (2) accumulate organic matter in surface soil through related species in soil crusts; (3) enhance the abilities of sand surface to resist wind erosion; (4) influence seed germination of vascular plants; and (5) enhance the production of dew deposition on sandy soil surface.

Na+ ions play an important role in the growth of halophyte. The effect of Na+ ions on nitrate uptake and osmotic adjustment in the euhalophyte Suaeda physophora was investigated under glasshouse conditions. Seedlings were exposed to 1 mmol/L NaCl (control), 300 mmol/L NaCl, 150 mmol/L NaCl plus 150 mmol/L KCl or 300 mmol/L KCl treatments for 24 d. Dry weight was not affected greatly by different salt treatments, but water content and succulence in leaves of S. physophora were significantly increased at 300 mmol/L NaCl and 150 mmol/L NaCl plus 150 mmol/L KCl treatments. The concentrations of Na+ and NO3- in leaves of S. physophora were the highest at 150 mmol/L NaCl plus 150 mmol/L KCl, but lowest at 300 mmol/L KCl treatment. Moreover, the increase of NO3- concentration did not result in the decrease of Cl- concentration at 150 mmol/L NaCl plus 150 mmol/L KCl treatments. The estimated contribution of NO3- to osmotic potential (CNO3) in leaves of S. physophora was 9.8% at 150 mmol/L NaCl plus 150 mmol/L KCl, and CNa and CCl were 31.0% and 23.3%, respectively. However, CNO3, CNa and CCl were respectively 1.6%, 7.9% and 11.9% at 300 mmol/L KCl treatment. It is concluded that Na+ stimulates NO3- absorption and the stimulation is independent on the internal or the external Cl- concentration in the euhalophyte S. physophora. These characteristics may explain the high levels of N in leaves of saline desert plants in arid ecosystem.

Kanas is a National Nature Reserve and National 5A Scenic Area, and it is also high on China’s National Natural Heritage List. In this paper, with an integrated analysis and comparative geographical approach, the genesis and current features of the Kanas landscape are analyzed systematically according to the criteria for outstanding universal values that must be met for designation by the United Nations as World Natural Heritage. It is concluded that Kanas has outstanding universal values in geosciences, biology and aesthetics. Through comparison with other World Natural Heritage sites of the same geological types, in the same biogeographic zone and in the same latitude, it is concluded that Kanas meets criteria vii, viii, ix and x for designation as World Natural Heritage. Thus, this work establishes a scientific foundation for nomination of Kanas for such a status.

Taking Gansu province as a model case, this study provides an integrated analysis on the eco-economic system of arid and semi-arid region based on emergy synthesis theory. Through calculating the values of renewable emergy flow, non-renewable resources, imported emergy, exported emergy, waste emergy, and total emergy during the period of 1978-2007, the performance of Gansu eco-economic system was analyzed. The results indicated that the renewable emergy flow within the province basically remained steady state which was estimated at 2.99×1022 solar emjoules (sej) from 1978 to 2007. The imported emergy and exported emergy were estimated at 3.75×1017 sej and 2.99×1020 sej in 1978 and increased to 1.07×1022 sej and 1.44×1022 sej respectively in 2007. The nonrenewable emergy flow was estimated at 1.62×1022 sej and increased to 1.85×1023 sej, with annual growth rate of 8.7%, while the estimated total emergy was 4.58×1022 sej in 1978 and increased to 2.11×1023 sej in 2007, with annual growth rate of 5.41%. Our results indicate a deteriorate situation between economic development and environmental protection in the region. The rapid economic growth in the past thirty years was based on a great consumption of nonrenewable resource and caused continuous decrease in the capacity of sustainable development. The environmental loading ratio was 0.53 in 1978, increased to 6.06 in 2007, indicating a rapid degradation of the regional environment quality. We calculated that the actual population was 1.53 times the renewable resource population in 1978, increased to 7.06 times in 2007. During the period of 1978-2007, the emergy rose from 2.45×1015 sej/(capita·a) to 8.07×1015 sej/(capita·a). Our analysis revealed that the emergy density presented a trend of gradual increase, and then the emergy currency ratio in Gansu decreased from 7.08×1013 sej/Chinese Yuan to 7.82×1012 sej/Chinese Yuan.

In this paper, the oasis cities in Kashgar Prefecture and Kizilsu Kirgiz Autonomous Prefecture are taken as an example, through the factor analysis, spatial attraction interaction model and location quotient methods, urban hierarchy system, the intensity of urban economic ties, economic subordination degree, and structure of city functions were analyzed. The results indicated: (1) The urban hierarchy system takes Kashgar city as the main center, Artux city, Yarkant county and Maralbexi county as the sub-centers; (2) The intensity of economic ties among Kashgar city and each county is much higher than others. The interaction of Kashgar city, Shufu county and Shule county are the strongest, and the economic ties of Yarkant, Kagilik, Poskam counties are relatively close; All cities in the study area are economically subordinate to Kashgar city. (3) Three cities of Kashgar city, Shufu county and Shule county should connect strongly, with Kashgar city as the core. The cities and towns along the Southern Xinjiang Railway and along National Road 315 should be regarded as two strips, and the two city strips along the border, and the city strip along Provincial Road 215 should be treated as three axes. The ring structure strategy of “core ring, closer ring and radiated ring” was proposed. (4) It was proposed to build Kashgar city group in the north, and Yarkant city group in the south, Maralbexi city group in the southeast, and Taxkorgan border city group with four inner groups’ development strategy.

Altai (also named Altay in China) Mountain Country (Mountain System) is a unique natural region, located on the border between different floristic regimes of the Boreal and ancient Mediterranean sub-kingdoms, where distribution of plant species is actually limited. It is known to have sufficient endemic floral biodiversity in the Northern Asia. Many plants of Altai Mountain System need effective care and proper conservation measures for their survival and longer-term protection. Important Plant Area identified as the IUCN (the International Union for Conservation of Nature), specified criteria attract global attention for protection of floral biodiversity across the world. The records of 71 plant species from the Chinese Altai Mountains attributed to the criterion A and the dark conifer forests of Chinese Altai Mountains satisfied the criterion C, which may help qualify to fulfill the national obligation of the Convention on Biological Diversity.

By examination of Calligonum pumilum A. Los. and Calligonum ruoqiangense Liou f., collected from natural habitats, and the analysis of their variance, this paper revealed that the morphological characters of these specimens are quite different from each other, especially in the twist direction of ribs on fruits, rows of bristles along each rib, rigidity, interweaving degree of bristles, and their geographical distribution. Therefore, it is suggested that C. pumilum and C. ruoqiangense should be considered as two independent species.