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Trade-offs are often required for an optimal and sustainable supply of competing services from forests. A study was conducted in northwest China to explore a practical trade-off approach, for promoting the rehabilitation of service-degraded plantation, focusing on the two main competing services of timber production and understory plant diversity conservation (expressed by understory vegetation species number [UVSN]). To describe the stand structure parameter variation with age and tree density, the logistic growth model and power function were coupled and fit with field data from 82 plots of larch (Larix principis-rupprechetii Mayr) plantation within the estimated age range of 12-33 years. The UVSN variation with canopy density and tree density were also quantified. These models and relations developed can serve as a tool for estimating trade-offs. The results showed that with rising tree density, the single tree timber volume decreased but the stand timber volume increased.The UVSN increased until its maximum, at the canopy density range of 0.6-0.7, and then decreased quickly. A proper tree density corresponding to the optimal canopy density of around 0.7 should be kept for maintaining higher UVSN and adequate timber production. In case of the larch plantation studied, optimal tree densities were found around 2,600, 2,000, 1,600, 1,250, and 1,000 trees/ha for the ages of 15, 20, 25, 30, and 35 years, respectively. Although only two main services were considered, the trade-off approach developed here can be a reference for future studies to guide the rehabilitation and multifunctional management of service-degraded plantation.

Land degradation in the form of soil erosion and fertility depletion is the major environmental problem in Ethiopia. However, to curb this problem, soil and water conservation (SWC) structures are commonly practiced in many rural parts of Ethiopia. This study was conducted to assess the effects of SWC structures on selected soil physicochemical properties in Ejersa Lafo district. For this study, two kebeles (peasant associations) were selected purposively from the district based on the severity of soil erosion and information on SWC practices. The research design employed in this study was systematic, randomized, complete block design. A total of 12 composite soil samples were collected from the depth of 0 to 20 cm at two subwatersheds, namely, Jamjam laga batu and Koriso Odo guba with SWC and without SWC structures at three landscape positions. All the soil samples were analyzed following the standard and recommended procedures. The effect of independent variables (SWC practices and landscape positions) on the dependent variables (soil properties) was statistically tested using the SPSS computer program 21. In this study, most of the selected soil physicochemical properties were affected by watershed management intervention (SWC) structures. Soil moisture content (SMC), clay, pH, electrical conductivity (EC), total N (TN), available (AP), available K (AK), and organic carbon (OC) were higher in the subwatershed treated with SWC structures (conserved), whereas bulk density, silt, and sand were higher in the subwatershed without SWC structures (nonconserved). Most of the selected soil chemical properties were significantly varied ( p < 0.05 ) between conserved and nonconserved farm land except EC. All the selected soil physicochemical properties did not show any significant variation ( p < 0.05 ) at landscape positions except sandy soil. The physicochemical soil properties of selected parameters were in good conditions in the conserved areas with higher N and OM and lower BD, indicating fertility of the soil compared with the nonconserved land. The implementation of SWC structures improved some of the physicochemical properties of soil, such as SMC, clay particle, pH, EC, total N, AP, AK, and OC in the study area. Furthermore, efforts are required to enhance community adoption towards soil and water conservation. Additionally, further research has to be carried out on socioeconomic aspects and impacts of the intervention on crop productivity for better understanding of the sustainable use of the land.

The snow leopard (Panthera uncia) is a cryptic and rare big cat inhabiting Asia’s remote and harsh elevated areas. Its population has decreased across the globe for various reasons, including human–snow leopard conflicts (HSCs). Understanding the snow leopard’s distribution range and habitat interactions with human/livestock is essential for understanding the ecological context in which HSCs occur and thus gives insights into how to mitigate HSCs. In this study, a MaxEnt model predicted the snow leopard’s potential distribution and analyzed the land use/cover to determine the habitat interactions of snow leopards with human/livestock in Karakoram–Pamir, northern Pakistan. The results indicated an excellent model performance for predicting the species’ potential distribution. The variables with higher contributions to the model were the mean diurnal temperature range (51.7%), annual temperature range (18.5%), aspect (14.2%), and land cover (6.9%). The model predicted approximately 10% of the study area as a highly suitable habitat for snow leopards. Appropriate areas included those at an altitude ranging from 2721 to 4825 m, with a mean elevation of 3796.9 ± 432 m, overlapping between suitable snow leopard habitats and human presence. The human encroachment (human settlements and agriculture) in suitable snow leopard habitat increased by 115% between 2008 and 2018. Increasing encroachment and a clear overlap between snow leopard suitable habitat and human activities, signs of growing competition between wildlife and human/livestock for limited rangeland resources, may have contributed to increasing HSCs. A sound land use plan is needed to minimize overlaps between suitable snow leopard habitat and human presence to mitigate HSCs in the long run.

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