Data from: An environmental impact assessment of different management regimes in eucalypt plantations in southern China using Landscape Function Analysis
Freudenberger, David (2020), Data from: An environmental impact assessment of different management regimes in eucalypt plantations in southern China using Landscape Function Analysis, Dryad, Dataset, https://doi.org/10.5061/dryad.905qftthd
There are global concerns regarding the detrimental environmental impacts of industrial forest plantations developed over the past 30 years. To address this concern, the Landscape Function Analysis methodology was used to rapidly assess indices of soil stability, water infiltration, and nutrient cycling within eucalypt plantations at different growth stages and under different management regimes in Guangxi Province, China. Results showed that these plantations under both regimes were approaching an ecologically functional state by the time of harvest. However, within the plantation management that included the burning of post-harvest biomass residues, indices of water infiltration, and nutrient cycling were significantly lower than within the plantation that retained post-harvest residues. Indicators of rain splash protection, perennial vegetation cover, and litter accumulation were all lower in the plantation that practiced residue burning and pre-planting cultivation. Retention of post-harvest residues improves landscape functionality at the time of re-planting. Our results indicate that burning and extensive cultivation prior to re-planting should be minimized.
We compared landscape functionality under two different management regimes in Guangxi Province: post-harvest residue burning and extensive pre-planting cultivation near Dongmen (22.41N, 107.92E) compared to residue retention and minimal cultivation near Qinzhou (21.96N, 108.73E). Our research also examined whether there were any changes in landscape function within a full plantation cycle. Therefore plantations at the time of planting, mid-rotation stage and before harvesting were selected for assessment. The number of survey transects per plantation site and the number of sites per growth stage were based on local situations such as the size of the plantation unit and the uniformity of the landscape as shown in Table 1. The functionality of the plantation landscapes were assessed using the methodology of Tongway and Ludwig (2011) and field procedures described in detail in Tongway and Hindley (2004).
Slope-scale patchiness was quantified along a 50 m tape (transect) randomly positioned and orientated downslope. Patches and inter-patches were identified along each hillslope transect reflecting differences in vital resource availability and transport. A patch was defined as the area where resources (e.g. water and soil nutrients) accumulate while inter-patches were those areas where resources tend to be lost (leak) from the hillslope. Typical patches were areas of leaf litter cover or dense understory that developed in some sites by year three of the plantation rotation. Inter-patches were usually areas of bare soil. The cover length of each patch and inter-patch along the transect was recorded. The width of the patches at right angles to the transect was also recorded.
To assess the fine-scale functionality of the plantation landscapes, three indices of functionality were determined along the transect: soil stability, nutrient cycling, and water infiltration. These indices represent the capacity of the soil-landscape to resist erosive forces from rainfall and run-off, to infiltrate rainfall into the soil, and to recycle organic matter and nutrients back into the soil (Tongway & Ludwig, 2011). Direct (i.e. laboratory) measures of these three indices have been shown to correlate well with this method of visual assessment (Eldridge & Freudenberger, 2005; Tongway & Hindley, 2003). These indices were derived from the visual assessment of 11 soil surface indicators
Soil surface assessments followed the field procedure described in Tongway and Hindley (2004). At each site, 3-4 randomly transects were located and the width and length of each patch and inter-patch type were measured along the 50 m transect. Field data entry sheets were obtained from D. Tongway (http://members.iinet.net.au/~lfa_procedures/).