Subsistence yields for maize, soybean, wheat and rice used for analysis in the study "Geography and availability of natural habitat determine whether cropland intensification or expansion is more detrimental to biodiversity"

ISIMIP is an international network of climate-impact modellers who develop and provide datasets for cross-sectorally consistent climate impact modeling. This data is ISIMIP2a data from the EPIC-BOKU model &amp; WFDEI.GPCC climate forcing (PM set, Penman-Monteith evapotranspiration calculation method), for the default setup and four crops (corn, soybean, rice and winter wheat) under subsistence management. The first string ("CRXXXYYY") of the first field is a unique gridcell identifier of a global half-degree grid. There might be more than 1 record per CR (could be averaged). The mapping between the 'CRXXXYYY' field and half-degree grid lat-lon coordinates is the following:lon = (as.numeric(XXX) - 1)*0.5 - 179.75lat = 89.75 + 0.5*(1 - as.numeric(YYY))YLDG: dry‐matter yield (t DM / ha, to be used as harvested crop yield for grain and tubers)<br>YLDF: raw dry‐matter yield (t DM / ha, to be used as harvested crop yield for cotton and sugar cane)BIOM: total biomass (t DM / ha)<br>YLN: N used by crop in biomass (kg/ha)<br>YLP: P used by crop in biomass (kg/ha)<br>FTN: N applied (kg/ha)<br>IRGA: irrigation volume applied (mm)<br>YLC: C in biomass

ISIMIP是一个由气候影响建模人员组成的国际网络，旨在开发并提供支持跨部门一致性气候影响建模的数据集。本数据集为基于EPIC-BOKU模型与WFDEI.GPCC气候强迫数据（PM集，彭曼-蒙特腾（Penman-Monteith）蒸散量计算方法）的ISIMIP2a数据，覆盖生计管理模式下的四种作物（玉米、大豆、水稻、冬小麦）的默认配置场景。
首个字段的首字符串为"CRXXXYYY"，其为全球半度网格的唯一网格单元标识符。每个CR标识可能对应多条记录（可进行平均化处理）。"CRXXXYYY"字段与半度网格经纬度坐标的映射关系如下：
经度（lon） = (as.numeric(XXX) - 1)*0.5 - 179.75
纬度（lat） = 89.75 + 0.5*(1 - as.numeric(YYY))
各变量含义如下：
YLDG：干物质产量（单位：吨干物质/公顷，可作为谷物与块根类作物的收获产量）
YLDF：原始干物质产量（单位：吨干物质/公顷，可作为棉花与甘蔗的收获产量）
BIOM：总生物量（单位：吨干物质/公顷）
YLN：作物生物量所吸收的氮素（单位：千克/公顷）
YLP：作物生物量所吸收的磷素（单位：千克/公顷）
FTN：施氮总量（单位：千克/公顷）
IRGA：灌溉施加量（单位：毫米）
YLC：生物量中的碳含量