[Spatial Heterogeneity of Soil Respiration in the Soil Erosion Area of West Mountains in Fujian Province, China].

The spatial heterogeneity of soil respiration () is of great significance in accurately estimating the carbon budget in erosion areas. This study investigated the soil respiration (), total nitrogen (TN), carbon-nitrogen ratio (C/N), soil organic carbon content (SOC), leaf area index (LAI), soil temperature (), and soil moisture () in 59 soil samples collected from Hetian Town in Fujian Province. Both classical statistics and geostatistics were used to analyze the spatial heterogeneity of soil respirations and other measured factors.

[Spatial and temporal changes of the ecological vulnerability in a serious soil erosion area, Southern China.].

Research on eco-environment vulnerability assessment contributes to the ecological environmental conservation and restoration. With Changting County as the study area, this paper selec-ted 7 indicators including slope, soil type, multi-year average precipitation, elevation deviate degree, normalized difference vegetation index, population density and land use type to build ecological vulnerability assessment system by using multicollinearity diagnostics analysis approach. The quantitative assessment of ecological vulnerability in 1999, 2006 and 2014 was calculated by using entropy weight method and comprehensive index method.

[Construction of age group vegetation index and preliminary application].

In the present paper, one remote sensing index-age group vegetation index (AGVI) was put forward, and its feasibility was verified. Taking 518 groups of pine forest age group data collected in 13 counties (cities) of Sanming, Jiangle, Shaxian, Nanping, Huaan, Yunxiao, Nanping, Anxi, Putian, Changting, Jianyang, Ningde and Fuqing, Fujian Province and HJ-1 CCD multi-spectral image at the same time-phase as the basis, the spectrum differences of blue, green, red, near infrared and NDVI of each age group were analyzed, showing the characteristics of young forest>middle-aged forest>over-mature forest>mature forest>near mature forest at near infrared band and mature forest>near mature forest>over-mature forest>young forest>middle-aged forest at NDVI, thus the age group vegetation index (AGVI) was constructed; the index could increase the absolute and relative spectrum differences among age groups. For the pine forest AGVI, cluster analysis was conducted with K-mean method, showing that the division accuracy of pine forest age group was 80.

[Construction of vegetation shadow index (SVI) and application effects in four remote sensing images].

Taking the images of Landsat TM, ALOS AVNIR-2, CBERS-02B CCD and HJ-1 CCD as the experimental data, for increasing the differences among shaded area, bright area and water further, the present paper construed a novel vegetation index-Shaded Vegetation Index(SVI), which can not only keep the absolute differences among bright area, shaded area and water area in the near-infrared band, but also can enlarge NDVI, eliminate the possible mixes, and change the histogram "skewed" phenomenon of NDVI, so the vegetation index value is closer to normal distribution, and more in line with the filed condition; this new index was applied to the surface features of large difference of the near-infrared radiation characteristics. Verified by accuracy assessment for the bright area, shaded area and water area recognition effects with SVI, it was showed that the overall classification accuracies of these images were up to 98. 89%, 100%, 97.

[Spectral features analysis of Pinus massoniana with pest of Dendrolimus punctatus Walker and levels detection].

Taking 51 field measured hyperspectral data with different pest levels in Yanping, Fujian Province as objects, the spectral reflectance and first derivative features of 4 levels of healthy, mild, moderate and severe insect pest were analyzed. On the basis of 7 detecting parameters construction, the pest level detecting models were built. The results showed that (1) the spectral reflectance of Pinus massoniana with pests were significantly lower than that of healthy state, and the higher the pest level, the lower the reflectance; (2) with the increase in pest level, the spectral reflectance curves' "green peak" and "red valley" of Pinus massoniana gradually disappeared, and the red edge was leveleds (3) the pest led to spectral "green peak" red shift, red edge position blue shift, but the changes in "red valley" and near-infrared position were complicated; (4) CARI, RES, REA and REDVI were highly relevant to pest levels, and the correlations between REP, RERVI, RENDVI and pest level were weak; (5) the multiple linear regression model with the variables of the 7 detection parameters could effectively detect the pest levels of Dendrolimus punctatus Walker, with both the estimation rate and accuracy above 0.