Land surface temperature (LST) can reflect the land surface water-heat exchange process comprehensively, which is considerably significant to the study of environmental change. However, research about LST in karst mountain areas with complex topography is scarce. Therefore, we retrieved the LST in a karst mountain area from Landsat 8 data and explored its relationships with LUCC and NDVI. The results showed that LST of the study area was noticeably affected by altitude and underlying surface type. In summer, abnormal high-temperature zones were observed in the study area, perhaps due to karst rocky desertification. LSTs among different land use types significantly differed with the highest in construction land and the lowest in woodland. The spatial distributions of NDVI and LST exhibited opposite patterns. Under the spatial combination of different land use types, the LST–NDVI feature space showed an obtuse-angled triangle shape and showed a negative linear correlation after removing water body data. In summary, the LST can be retrieved well by the atmospheric correction model from Landsat 8 data. Moreover, the LST of the karst mountain area is controlled by altitude, underlying surface type and aspect. This study provides a reference for land use planning, ecological environment restoration in karst areas.

Karst rocky desertification (KRD) has become one of the most important eco‐environmental problems in China. In order to put forward valid restoration strategies, the spatial‐temporal KRD evolution processes were analyzed mathematically using 1:100 000 scale digital KRD distribution maps of Guizhou Province obtained from interpreting Landsat images from 1986, 1995, and 2000. The results showed that: (1) no obvious change took place in the total area of KRD land, but the mutual transformation of different types of KRD land was remarkable. (2) The change patterns of KRD land were classified into three types: simple mode, continuous mode, and reverted mode. (3) The total change rate of KRD land was 398·31 km2 per year. (4) The higher the rank of KRD land is, the lower the change rate of KRD land will be. (5) Moderate KRD land had the fastest change frequency and was feasible to change to another type. On the whole, these indicated that the expansion of KRD had been brought under control because of the successful execution many ecological construction programmes. However, new KRD land appeared meanwhile owing to ‘backward’ eco‐social development, and this should be clearly recognized. Copyright © 2011 John Wiley & Sons, Ltd.

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Diagnosing the evolution trends of vegetation and its drivers is necessary for ecological conservation and restoration. However, it remains unclear what the underlying distribution pattern of these trends and its correlation with some drivers at large spatial-temporal scales. Here we use the normalized difference vegetation index (NDVI) to quantify the activity of vegetation by Theil–Sen median trend analysis and the Mann–Kendall test, Pearson correlation analysis and Boosted regression trees (BRT) model. Results show that about 34% of the global continent area has experienced greening in the grid annual NDVI from 1982 to 2015. The major greening areas were observed in the Sahel, European, India and south China. Only 10% of the global continent land areas were browning, and these were observed in Canada, South America, central Africa and Central Asia. BRT model shows that rainfall is the most important factor affecting vegetation evolution (63.1%), followed by temperature (15%), land cover change (8.6%), population (6.5%), elevation (6.4%) and nightlight (0.4%). It’s about 21% of the world’s continent were affected by rainfall, mainly in arid regions such as central Asia and Australia. The main temperature-affected areas accounted for 36%, located near the equator or in high latitudes.

The carbon (δ 13 C org ) and nitrogen (δ 15 N) isotopic compositions of bulk organic matter were analyzed in two high-resolution Permian-Triassic transitional sections containing microbialite in south China. The results from these shallow-marine sections show that an abrupt negative shift in δ 15 N, from ~+3‰ to ~0‰, occurred immediately after the latest Permian mass extinction (LPE) in both sections, concurrent with a distinct negative shift in δ 13 C org . The persistently low values of δ 15 N suggest that, following the LPE, microbial nitrogen fi xation became the main source of biologically available nitrogen in the Nanpanjiang Basin and perhaps over a broader region of the eastern Paleotethys Ocean. Enhanced N fi xation is probably indicative of the prevalence of stratifi ed anoxic water masses characterized by intense denitrifi cation and/or anaerobic ammonium oxidation at the time. Perturbation of the marine nitrogen cycle might have contributed to high temperatures following the main marine mass extinction through the release of the greenhouse gas N 2 O. The sharp declines in δ 15 N and δ 13 C org may be ascribed to an abrupt change in shallow-water microbial communities, which differed in composition from contemporaneous deep-water communities.

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